diff --git a/libcxx/docs/FeatureTestMacroTable.rst b/libcxx/docs/FeatureTestMacroTable.rst
index cfb0e5cfb129c..ccaa784ccb088 100644
--- a/libcxx/docs/FeatureTestMacroTable.rst
+++ b/libcxx/docs/FeatureTestMacroTable.rst
@@ -330,6 +330,10 @@ Status
---------------------------------------------------------- -----------------
``__cpp_lib_expected`` ``202211L``
---------------------------------------------------------- -----------------
+ ``__cpp_lib_flat_map`` ``202207L``
+ ---------------------------------------------------------- -----------------
+ ``__cpp_lib_flat_set`` *unimplemented*
+ ---------------------------------------------------------- -----------------
``__cpp_lib_format_ranges`` ``202207L``
---------------------------------------------------------- -----------------
``__cpp_lib_formatters`` *unimplemented*
diff --git a/libcxx/docs/Status/Cxx23Papers.csv b/libcxx/docs/Status/Cxx23Papers.csv
index 24398574064e6..bc9d4f8866a73 100644
--- a/libcxx/docs/Status/Cxx23Papers.csv
+++ b/libcxx/docs/Status/Cxx23Papers.csv
@@ -52,7 +52,7 @@
"`P2443R1 <https://wg21.link/P2443R1>`__","``views::chunk_by``","2022-02 (Virtual)","|Complete|","18",""
"","","","","",""
"`P0009R18 <https://wg21.link/P0009R18>`__","mdspan: A Non-Owning Multidimensional Array Reference","2022-07 (Virtual)","|Complete|","18",""
-"`P0429R9 <https://wg21.link/P0429R9>`__","A Standard ``flat_map``","2022-07 (Virtual)","|In Progress|","",""
+"`P0429R9 <https://wg21.link/P0429R9>`__","A Standard ``flat_map``","2022-07 (Virtual)","|Complete|","",""
"`P1169R4 <https://wg21.link/P1169R4>`__","``static operator()``","2022-07 (Virtual)","|Complete|","16",""
"`P1222R4 <https://wg21.link/P1222R4>`__","A Standard ``flat_set``","2022-07 (Virtual)","","",""
"`P1223R5 <https://wg21.link/P1223R5>`__","``ranges::find_last()``, ``ranges::find_last_if()``, and ``ranges::find_last_if_not()``","2022-07 (Virtual)","|Complete|","19",""
diff --git a/libcxx/include/CMakeLists.txt b/libcxx/include/CMakeLists.txt
index f3313bf53460a..ba2723a5804f8 100644
--- a/libcxx/include/CMakeLists.txt
+++ b/libcxx/include/CMakeLists.txt
@@ -361,8 +361,11 @@ set(files
__filesystem/space_info.h
__filesystem/u8path.h
__flat_map/flat_map.h
+ __flat_map/flat_multimap.h
__flat_map/key_value_iterator.h
+ __flat_map/sorted_equivalent.h
__flat_map/sorted_unique.h
+ __flat_map/utils.h
__format/buffer.h
__format/concepts.h
__format/container_adaptor.h
diff --git a/libcxx/include/__flat_map/flat_map.h b/libcxx/include/__flat_map/flat_map.h
index ab53b7a285ca4..a0594ed9dc411 100644
--- a/libcxx/include/__flat_map/flat_map.h
+++ b/libcxx/include/__flat_map/flat_map.h
@@ -29,9 +29,11 @@
#include <__cstddef/ptrdiff_t.h>
#include <__flat_map/key_value_iterator.h>
#include <__flat_map/sorted_unique.h>
+#include <__flat_map/utils.h>
#include <__functional/invoke.h>
#include <__functional/is_transparent.h>
#include <__functional/operations.h>
+#include <__fwd/vector.h>
#include <__iterator/concepts.h>
#include <__iterator/distance.h>
#include <__iterator/iterator_traits.h>
@@ -131,7 +133,7 @@ class flat_map {
_LIBCPP_HIDE_FROM_ABI static constexpr bool __allocator_ctor_constraint =
_And<uses_allocator<key_container_type, _Allocator>, uses_allocator<mapped_container_type, _Allocator>>::value;
- _LIBCPP_HIDE_FROM_ABI static constexpr bool __is_compare_transparent = __is_transparent_v<_Compare, _Compare>;
+ _LIBCPP_HIDE_FROM_ABI static constexpr bool __is_compare_transparent = __is_transparent_v<_Compare>;
public:
// [flat.map.cons], construct/copy/destroy
@@ -153,7 +155,7 @@ class flat_map {
# if _LIBCPP_HAS_EXCEPTIONS
} catch (...) {
__other.clear();
- // gcc does not like the `throw` keyword in a conditional noexcept function
+ // gcc does not like the `throw` keyword in a conditionally noexcept function
if constexpr (!(is_nothrow_move_constructible_v<_KeyContainer> &&
is_nothrow_move_constructible_v<_MappedContainer> && is_nothrow_move_constructible_v<_Compare>)) {
throw;
@@ -518,16 +520,16 @@ class flat_map {
return emplace_hint(__hint, std::move(__x));
}
- template <class _Pp>
- requires is_constructible_v<pair<key_type, mapped_type>, _Pp>
- _LIBCPP_HIDE_FROM_ABI pair<iterator, bool> insert(_Pp&& __x) {
- return emplace(std::forward<_Pp>(__x));
+ template <class _PairLike>
+ requires is_constructible_v<pair<key_type, mapped_type>, _PairLike>
+ _LIBCPP_HIDE_FROM_ABI pair<iterator, bool> insert(_PairLike&& __x) {
+ return emplace(std::forward<_PairLike>(__x));
}
- template <class _Pp>
- requires is_constructible_v<pair<key_type, mapped_type>, _Pp>
- _LIBCPP_HIDE_FROM_ABI iterator insert(const_iterator __hint, _Pp&& __x) {
- return emplace_hint(__hint, std::forward<_Pp>(__x));
+ template <class _PairLike>
+ requires is_constructible_v<pair<key_type, mapped_type>, _PairLike>
+ _LIBCPP_HIDE_FROM_ABI iterator insert(const_iterator __hint, _PairLike&& __x) {
+ return emplace_hint(__hint, std::forward<_PairLike>(__x));
}
template <class _InputIterator>
@@ -860,22 +862,10 @@ class flat_map {
__containers_.values.erase(__containers_.values.begin() + __dist, __containers_.values.end());
}
- template <class _InputIterator, class _Sentinel>
- _LIBCPP_HIDE_FROM_ABI size_type __append(_InputIterator __first, _Sentinel __last) {
- size_type __num_of_appended = 0;
- for (; __first != __last; ++__first) {
- value_type __kv = *__first;
- __containers_.keys.insert(__containers_.keys.end(), std::move(__kv.first));
- __containers_.values.insert(__containers_.values.end(), std::move(__kv.second));
- ++__num_of_appended;
- }
- return __num_of_appended;
- }
-
template <bool _WasSorted, class _InputIterator, class _Sentinel>
_LIBCPP_HIDE_FROM_ABI void __append_sort_merge_unique(_InputIterator __first, _Sentinel __last) {
auto __on_failure = std::__make_exception_guard([&]() noexcept { clear() /* noexcept */; });
- size_t __num_of_appended = __append(std::move(__first), std::move(__last));
+ size_t __num_of_appended = __flat_map_utils::__append(*this, std::move(__first), std::move(__last));
if (__num_of_appended != 0) {
auto __zv = ranges::views::zip(__containers_.keys, __containers_.values);
auto __append_start_offset = __containers_.keys.size() - __num_of_appended;
@@ -963,7 +953,8 @@ class flat_map {
if (__key_it == __containers_.keys.end() || __compare_(__key, *__key_it)) {
return pair<iterator, bool>(
- __try_emplace_exact_hint(
+ __flat_map_utils::__emplace_exact_pos(
+ *this,
std::move(__key_it),
std::move(__mapped_it),
std::forward<_KeyArg>(__key),
@@ -989,10 +980,13 @@ class flat_map {
_LIBCPP_HIDE_FROM_ABI pair<iterator, bool> __try_emplace_hint(const_iterator __hint, _Kp&& __key, _Args&&... __args) {
if (__is_hint_correct(__hint, __key)) {
if (__hint == cend() || __compare_(__key, __hint->first)) {
- return {
- __try_emplace_exact_hint(
- __hint.__key_iter_, __hint.__mapped_iter_, std::forward<_Kp>(__key), std::forward<_Args>(__args)...),
- true};
+ return {__flat_map_utils::__emplace_exact_pos(
+ *this,
+ __hint.__key_iter_,
+ __hint.__mapped_iter_,
+ std::forward<_Kp>(__key),
+ std::forward<_Args>(__args)...),
+ true};
} else {
// key equals
auto __dist = __hint - cbegin();
@@ -1003,49 +997,6 @@ class flat_map {
}
}
- template <class _IterK, class _IterM, class _KeyArg, class... _MArgs>
- _LIBCPP_HIDE_FROM_ABI iterator
- __try_emplace_exact_hint(_IterK&& __it_key, _IterM&& __it_mapped, _KeyArg&& __key, _MArgs&&... __mapped_args) {
- auto __on_key_failed = std::__make_exception_guard([&]() noexcept {
- if constexpr (__container_traits<_KeyContainer>::__emplacement_has_strong_exception_safety_guarantee) {
- // Nothing to roll back!
- } else {
- // we need to clear both because we don't know the state of our keys anymore
- clear() /* noexcept */;
- }
- });
- auto __key_it = __containers_.keys.emplace(__it_key, std::forward<_KeyArg>(__key));
- __on_key_failed.__complete();
-
- auto __on_value_failed = std::__make_exception_guard([&]() noexcept {
- if constexpr (!__container_traits<_MappedContainer>::__emplacement_has_strong_exception_safety_guarantee) {
- // we need to clear both because we don't know the state of our values anymore
- clear() /* noexcept */;
- } else {
- // In this case, we know the values are just like before we attempted emplacement,
- // and we also know that the keys have been emplaced successfully. Just roll back the keys.
-# if _LIBCPP_HAS_EXCEPTIONS
- try {
-# endif // _LIBCPP_HAS_EXCEPTIONS
- __containers_.keys.erase(__key_it);
-# if _LIBCPP_HAS_EXCEPTIONS
- } catch (...) {
- // Now things are funky for real. We're failing to rollback the keys.
- // Just give up and clear the whole thing.
- //
- // Also, swallow the exception that happened during the rollback and let the
- // original value-emplacement exception propagate normally.
- clear() /* noexcept */;
- }
-# endif // _LIBCPP_HAS_EXCEPTIONS
- }
- });
- auto __mapped_it = __containers_.values.emplace(__it_mapped, std::forward<_MArgs>(__mapped_args)...);
- __on_value_failed.__complete();
-
- return iterator(std::move(__key_it), std::move(__mapped_it));
- }
-
template <class _Kp, class _Mapped>
_LIBCPP_HIDE_FROM_ABI pair<iterator, bool> __insert_or_assign(_Kp&& __key, _Mapped&& __mapped) {
auto __r = try_emplace(std::forward<_Kp>(__key), std::forward<_Mapped>(__mapped));
@@ -1087,8 +1038,10 @@ class flat_map {
friend typename flat_map<_Key2, _Tp2, _Compare2, _KeyContainer2, _MappedContainer2>::size_type
erase_if(flat_map<_Key2, _Tp2, _Compare2, _KeyContainer2, _MappedContainer2>&, _Predicate);
+ friend __flat_map_utils;
+
containers __containers_;
- [[no_unique_address]] key_compare __compare_;
+ _LIBCPP_NO_UNIQUE_ADDRESS key_compare __compare_;
struct __key_equiv {
_LIBCPP_HIDE_FROM_ABI __key_equiv(key_compare __c) : __comp_(__c) {}
@@ -1187,22 +1140,20 @@ template <ranges::input_range _Range,
class _Compare = less<__range_key_type<_Range>>,
class _Allocator = allocator<byte>,
class = __enable_if_t<!__is_allocator<_Compare>::value && __is_allocator<_Allocator>::value>>
-flat_map(from_range_t, _Range&&, _Compare = _Compare(), _Allocator = _Allocator())
- -> flat_map<
- __range_key_type<_Range>,
- __range_mapped_type<_Range>,
- _Compare,
- vector<__range_key_type<_Range>, __allocator_traits_rebind_t<_Allocator, __range_key_type<_Range>>>,
- vector<__range_mapped_type<_Range>, __allocator_traits_rebind_t<_Allocator, __range_mapped_type<_Range>>>>;
+flat_map(from_range_t, _Range&&, _Compare = _Compare(), _Allocator = _Allocator()) -> flat_map<
+ __range_key_type<_Range>,
+ __range_mapped_type<_Range>,
+ _Compare,
+ vector<__range_key_type<_Range>, __allocator_traits_rebind_t<_Allocator, __range_key_type<_Range>>>,
+ vector<__range_mapped_type<_Range>, __allocator_traits_rebind_t<_Allocator, __range_mapped_type<_Range>>>>;
template <ranges::input_range _Range, class _Allocator, class = __enable_if_t<__is_allocator<_Allocator>::value>>
-flat_map(from_range_t, _Range&&, _Allocator)
- -> flat_map<
- __range_key_type<_Range>,
- __range_mapped_type<_Range>,
- less<__range_key_type<_Range>>,
- vector<__range_key_type<_Range>, __allocator_traits_rebind_t<_Allocator, __range_key_type<_Range>>>,
- vector<__range_mapped_type<_Range>, __allocator_traits_rebind_t<_Allocator, __range_mapped_type<_Range>>>>;
+flat_map(from_range_t, _Range&&, _Allocator) -> flat_map<
+ __range_key_type<_Range>,
+ __range_mapped_type<_Range>,
+ less<__range_key_type<_Range>>,
+ vector<__range_key_type<_Range>, __allocator_traits_rebind_t<_Allocator, __range_key_type<_Range>>>,
+ vector<__range_mapped_type<_Range>, __allocator_traits_rebind_t<_Allocator, __range_mapped_type<_Range>>>>;
template <class _Key, class _Tp, class _Compare = less<_Key>>
requires(!__is_allocator<_Compare>::value)
diff --git a/libcxx/include/__flat_map/flat_multimap.h b/libcxx/include/__flat_map/flat_multimap.h
new file mode 100644
index 0000000000000..ea77fb5d79bd2
--- /dev/null
+++ b/libcxx/include/__flat_map/flat_multimap.h
@@ -0,0 +1,1010 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___FLAT_MAP_FLAT_MULTIMAP_H
+#define _LIBCPP___FLAT_MAP_FLAT_MULTIMAP_H
+
+#include <__algorithm/lexicographical_compare_three_way.h>
+#include <__algorithm/min.h>
+#include <__algorithm/ranges_equal.h>
+#include <__algorithm/ranges_equal_range.h>
+#include <__algorithm/ranges_inplace_merge.h>
+#include <__algorithm/ranges_is_sorted.h>
+#include <__algorithm/ranges_lower_bound.h>
+#include <__algorithm/ranges_partition_point.h>
+#include <__algorithm/ranges_sort.h>
+#include <__algorithm/ranges_unique.h>
+#include <__algorithm/ranges_upper_bound.h>
+#include <__algorithm/remove_if.h>
+#include <__assert>
+#include <__compare/synth_three_way.h>
+#include <__concepts/convertible_to.h>
+#include <__concepts/swappable.h>
+#include <__config>
+#include <__cstddef/byte.h>
+#include <__cstddef/ptrdiff_t.h>
+#include <__flat_map/key_value_iterator.h>
+#include <__flat_map/sorted_equivalent.h>
+#include <__flat_map/utils.h>
+#include <__functional/invoke.h>
+#include <__functional/is_transparent.h>
+#include <__functional/operations.h>
+#include <__fwd/vector.h>
+#include <__iterator/concepts.h>
+#include <__iterator/distance.h>
+#include <__iterator/iterator_traits.h>
+#include <__iterator/ranges_iterator_traits.h>
+#include <__iterator/reverse_iterator.h>
+#include <__memory/allocator_traits.h>
+#include <__memory/uses_allocator.h>
+#include <__memory/uses_allocator_construction.h>
+#include <__ranges/access.h>
+#include <__ranges/concepts.h>
+#include <__ranges/container_compatible_range.h>
+#include <__ranges/drop_view.h>
+#include <__ranges/from_range.h>
+#include <__ranges/ref_view.h>
+#include <__ranges/size.h>
+#include <__ranges/subrange.h>
+#include <__ranges/zip_view.h>
+#include <__type_traits/conjunction.h>
+#include <__type_traits/container_traits.h>
+#include <__type_traits/invoke.h>
+#include <__type_traits/is_allocator.h>
+#include <__type_traits/is_nothrow_constructible.h>
+#include <__type_traits/is_same.h>
+#include <__type_traits/maybe_const.h>
+#include <__utility/exception_guard.h>
+#include <__utility/move.h>
+#include <__utility/pair.h>
+#include <__utility/scope_guard.h>
+#include <__vector/vector.h>
+#include <initializer_list>
+#include <stdexcept>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+#if _LIBCPP_STD_VER >= 23
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _Key,
+ class _Tp,
+ class _Compare = less<_Key>,
+ class _KeyContainer = vector<_Key>,
+ class _MappedContainer = vector<_Tp>>
+class flat_multimap {
+ template <class, class, class, class, class>
+ friend class flat_multimap;
+
+ static_assert(is_same_v<_Key, typename _KeyContainer::value_type>);
+ static_assert(is_same_v<_Tp, typename _MappedContainer::value_type>);
+ static_assert(!is_same_v<_KeyContainer, std::vector<bool>>, "vector<bool> is not a sequence container");
+ static_assert(!is_same_v<_MappedContainer, std::vector<bool>>, "vector<bool> is not a sequence container");
+
+ template <bool _Const>
+ using __iterator _LIBCPP_NODEBUG = __key_value_iterator<flat_multimap, _KeyContainer, _MappedContainer, _Const>;
+
+public:
+ // types
+ using key_type = _Key;
+ using mapped_type = _Tp;
+ using value_type = pair<key_type, mapped_type>;
+ using key_compare = __type_identity_t<_Compare>;
+ using reference = pair<const key_type&, mapped_type&>;
+ using const_reference = pair<const key_type&, const mapped_type&>;
+ using size_type = size_t;
+ using difference_type = ptrdiff_t;
+ using iterator = __iterator<false>; // see [container.requirements]
+ using const_iterator = __iterator<true>; // see [container.requirements]
+ using reverse_iterator = std::reverse_iterator<iterator>;
+ using const_reverse_iterator = std::reverse_iterator<const_iterator>;
+ using key_container_type = _KeyContainer;
+ using mapped_container_type = _MappedContainer;
+
+ class value_compare {
+ private:
+ key_compare __comp_;
+ _LIBCPP_HIDE_FROM_ABI value_compare(key_compare __c) : __comp_(__c) {}
+ friend flat_multimap;
+
+ public:
+ _LIBCPP_HIDE_FROM_ABI bool operator()(const_reference __x, const_reference __y) const {
+ return __comp_(__x.first, __y.first);
+ }
+ };
+
+ struct containers {
+ key_container_type keys;
+ mapped_container_type values;
+ };
+
+private:
+ template <class _Allocator>
+ _LIBCPP_HIDE_FROM_ABI static constexpr bool __allocator_ctor_constraint =
+ _And<uses_allocator<key_container_type, _Allocator>, uses_allocator<mapped_container_type, _Allocator>>::value;
+
+ _LIBCPP_HIDE_FROM_ABI static constexpr bool __is_compare_transparent = __is_transparent_v<_Compare>;
+
+public:
+ // [flat.map.cons], construct/copy/destroy
+ _LIBCPP_HIDE_FROM_ABI flat_multimap() noexcept(
+ is_nothrow_default_constructible_v<_KeyContainer> && is_nothrow_default_constructible_v<_MappedContainer> &&
+ is_nothrow_default_constructible_v<_Compare>)
+ : __containers_(), __compare_() {}
+
+ _LIBCPP_HIDE_FROM_ABI flat_multimap(const flat_multimap&) = default;
+
+ // The copy/move constructors are not specified in the spec, which means they should be defaulted.
+ // However, the move constructor can potentially leave a moved-from object in an inconsistent
+ // state if an exception is thrown.
+ _LIBCPP_HIDE_FROM_ABI flat_multimap(flat_multimap&& __other) noexcept(
+ is_nothrow_move_constructible_v<_KeyContainer> && is_nothrow_move_constructible_v<_MappedContainer> &&
+ is_nothrow_move_constructible_v<_Compare>)
+# if _LIBCPP_HAS_EXCEPTIONS
+ try
+# endif // _LIBCPP_HAS_EXCEPTIONS
+ : __containers_(std::move(__other.__containers_)), __compare_(std::move(__other.__compare_)) {
+ __other.clear();
+# if _LIBCPP_HAS_EXCEPTIONS
+ } catch (...) {
+ __other.clear();
+ // gcc does not like the `throw` keyword in a conditionally noexcept function
+ if constexpr (!(is_nothrow_move_constructible_v<_KeyContainer> &&
+ is_nothrow_move_constructible_v<_MappedContainer> && is_nothrow_move_constructible_v<_Compare>)) {
+ throw;
+ }
+# endif // _LIBCPP_HAS_EXCEPTIONS
+ }
+
+ template <class _Allocator>
+ requires __allocator_ctor_constraint<_Allocator>
+ _LIBCPP_HIDE_FROM_ABI flat_multimap(const flat_multimap& __other, const _Allocator& __alloc)
+ : flat_multimap(__ctor_uses_allocator_tag{},
+ __alloc,
+ __other.__containers_.keys,
+ __other.__containers_.values,
+ __other.__compare_) {}
+
+ template <class _Allocator>
+ requires __allocator_ctor_constraint<_Allocator>
+ _LIBCPP_HIDE_FROM_ABI flat_multimap(flat_multimap&& __other, const _Allocator& __alloc)
+# if _LIBCPP_HAS_EXCEPTIONS
+ try
+# endif // _LIBCPP_HAS_EXCEPTIONS
+ : flat_multimap(__ctor_uses_allocator_tag{},
+ __alloc,
+ std::move(__other.__containers_.keys),
+ std::move(__other.__containers_.values),
+ std::move(__other.__compare_)) {
+ __other.clear();
+# if _LIBCPP_HAS_EXCEPTIONS
+ } catch (...) {
+ __other.clear();
+ throw;
+# endif // _LIBCPP_HAS_EXCEPTIONS
+ }
+
+ _LIBCPP_HIDE_FROM_ABI flat_multimap(
+ key_container_type __key_cont, mapped_container_type __mapped_cont, const key_compare& __comp = key_compare())
+ : __containers_{.keys = std::move(__key_cont), .values = std::move(__mapped_cont)}, __compare_(__comp) {
+ _LIBCPP_ASSERT_VALID_INPUT_RANGE(__containers_.keys.size() == __containers_.values.size(),
+ "flat_multimap keys and mapped containers have different size");
+ __sort();
+ }
+
+ template <class _Allocator>
+ requires __allocator_ctor_constraint<_Allocator>
+ _LIBCPP_HIDE_FROM_ABI flat_multimap(
+ const key_container_type& __key_cont, const mapped_container_type& __mapped_cont, const _Allocator& __alloc)
+ : flat_multimap(__ctor_uses_allocator_tag{}, __alloc, __key_cont, __mapped_cont) {
+ _LIBCPP_ASSERT_VALID_INPUT_RANGE(__containers_.keys.size() == __containers_.values.size(),
+ "flat_multimap keys and mapped containers have different size");
+ __sort();
+ }
+
+ template <class _Allocator>
+ requires __allocator_ctor_constraint<_Allocator>
+ _LIBCPP_HIDE_FROM_ABI
+ flat_multimap(const key_container_type& __key_cont,
+ const mapped_container_type& __mapped_cont,
+ const key_compare& __comp,
+ const _Allocator& __alloc)
+ : flat_multimap(__ctor_uses_allocator_tag{}, __alloc, __key_cont, __mapped_cont, __comp) {
+ _LIBCPP_ASSERT_VALID_INPUT_RANGE(__containers_.keys.size() == __containers_.values.size(),
+ "flat_multimap keys and mapped containers have different size");
+ __sort();
+ }
+
+ _LIBCPP_HIDE_FROM_ABI
+ flat_multimap(sorted_equivalent_t,
+ key_container_type __key_cont,
+ mapped_container_type __mapped_cont,
+ const key_compare& __comp = key_compare())
+ : __containers_{.keys = std::move(__key_cont), .values = std::move(__mapped_cont)}, __compare_(__comp) {
+ _LIBCPP_ASSERT_VALID_INPUT_RANGE(__containers_.keys.size() == __containers_.values.size(),
+ "flat_multimap keys and mapped containers have different size");
+ _LIBCPP_ASSERT_SEMANTIC_REQUIREMENT(__is_sorted(__containers_.keys), "Key container is not sorted");
+ }
+
+ template <class _Allocator>
+ requires __allocator_ctor_constraint<_Allocator>
+ _LIBCPP_HIDE_FROM_ABI
+ flat_multimap(sorted_equivalent_t,
+ const key_container_type& __key_cont,
+ const mapped_container_type& __mapped_cont,
+ const _Allocator& __alloc)
+ : flat_multimap(__ctor_uses_allocator_tag{}, __alloc, __key_cont, __mapped_cont) {
+ _LIBCPP_ASSERT_VALID_INPUT_RANGE(__containers_.keys.size() == __containers_.values.size(),
+ "flat_multimap keys and mapped containers have different size");
+ _LIBCPP_ASSERT_SEMANTIC_REQUIREMENT(__is_sorted(__containers_.keys), "Key container is not sorted");
+ }
+
+ template <class _Allocator>
+ requires __allocator_ctor_constraint<_Allocator>
+ _LIBCPP_HIDE_FROM_ABI
+ flat_multimap(sorted_equivalent_t,
+ const key_container_type& __key_cont,
+ const mapped_container_type& __mapped_cont,
+ const key_compare& __comp,
+ const _Allocator& __alloc)
+ : flat_multimap(__ctor_uses_allocator_tag{}, __alloc, __key_cont, __mapped_cont, __comp) {
+ _LIBCPP_ASSERT_VALID_INPUT_RANGE(__containers_.keys.size() == __containers_.values.size(),
+ "flat_multimap keys and mapped containers have different size");
+ _LIBCPP_ASSERT_SEMANTIC_REQUIREMENT(__is_sorted(__containers_.keys), "Key container is not sorted");
+ }
+
+ _LIBCPP_HIDE_FROM_ABI explicit flat_multimap(const key_compare& __comp) : __containers_(), __compare_(__comp) {}
+
+ template <class _Allocator>
+ requires __allocator_ctor_constraint<_Allocator>
+ _LIBCPP_HIDE_FROM_ABI flat_multimap(const key_compare& __comp, const _Allocator& __alloc)
+ : flat_multimap(__ctor_uses_allocator_empty_tag{}, __alloc, __comp) {}
+
+ template <class _Allocator>
+ requires __allocator_ctor_constraint<_Allocator>
+ _LIBCPP_HIDE_FROM_ABI explicit flat_multimap(const _Allocator& __alloc)
+ : flat_multimap(__ctor_uses_allocator_empty_tag{}, __alloc) {}
+
+ template <class _InputIterator>
+ requires __has_input_iterator_category<_InputIterator>::value
+ _LIBCPP_HIDE_FROM_ABI
+ flat_multimap(_InputIterator __first, _InputIterator __last, const key_compare& __comp = key_compare())
+ : __containers_(), __compare_(__comp) {
+ insert(__first, __last);
+ }
+
+ template <class _InputIterator, class _Allocator>
+ requires(__has_input_iterator_category<_InputIterator>::value && __allocator_ctor_constraint<_Allocator>)
+ _LIBCPP_HIDE_FROM_ABI
+ flat_multimap(_InputIterator __first, _InputIterator __last, const key_compare& __comp, const _Allocator& __alloc)
+ : flat_multimap(__ctor_uses_allocator_empty_tag{}, __alloc, __comp) {
+ insert(__first, __last);
+ }
+
+ template <class _InputIterator, class _Allocator>
+ requires(__has_input_iterator_category<_InputIterator>::value && __allocator_ctor_constraint<_Allocator>)
+ _LIBCPP_HIDE_FROM_ABI flat_multimap(_InputIterator __first, _InputIterator __last, const _Allocator& __alloc)
+ : flat_multimap(__ctor_uses_allocator_empty_tag{}, __alloc) {
+ insert(__first, __last);
+ }
+
+ template <_ContainerCompatibleRange<value_type> _Range>
+ _LIBCPP_HIDE_FROM_ABI flat_multimap(from_range_t __fr, _Range&& __rg)
+ : flat_multimap(__fr, std::forward<_Range>(__rg), key_compare()) {}
+
+ template <_ContainerCompatibleRange<value_type> _Range, class _Allocator>
+ requires __allocator_ctor_constraint<_Allocator>
+ _LIBCPP_HIDE_FROM_ABI flat_multimap(from_range_t, _Range&& __rg, const _Allocator& __alloc)
+ : flat_multimap(__ctor_uses_allocator_empty_tag{}, __alloc) {
+ insert_range(std::forward<_Range>(__rg));
+ }
+
+ template <_ContainerCompatibleRange<value_type> _Range>
+ _LIBCPP_HIDE_FROM_ABI flat_multimap(from_range_t, _Range&& __rg, const key_compare& __comp) : flat_multimap(__comp) {
+ insert_range(std::forward<_Range>(__rg));
+ }
+
+ template <_ContainerCompatibleRange<value_type> _Range, class _Allocator>
+ requires __allocator_ctor_constraint<_Allocator>
+ _LIBCPP_HIDE_FROM_ABI flat_multimap(from_range_t, _Range&& __rg, const key_compare& __comp, const _Allocator& __alloc)
+ : flat_multimap(__ctor_uses_allocator_empty_tag{}, __alloc, __comp) {
+ insert_range(std::forward<_Range>(__rg));
+ }
+
+ template <class _InputIterator>
+ requires __has_input_iterator_category<_InputIterator>::value
+ _LIBCPP_HIDE_FROM_ABI flat_multimap(
+ sorted_equivalent_t, _InputIterator __first, _InputIterator __last, const key_compare& __comp = key_compare())
+ : __containers_(), __compare_(__comp) {
+ insert(sorted_equivalent, __first, __last);
+ }
+ template <class _InputIterator, class _Allocator>
+ requires(__has_input_iterator_category<_InputIterator>::value && __allocator_ctor_constraint<_Allocator>)
+ _LIBCPP_HIDE_FROM_ABI
+ flat_multimap(sorted_equivalent_t,
+ _InputIterator __first,
+ _InputIterator __last,
+ const key_compare& __comp,
+ const _Allocator& __alloc)
+ : flat_multimap(__ctor_uses_allocator_empty_tag{}, __alloc, __comp) {
+ insert(sorted_equivalent, __first, __last);
+ }
+
+ template <class _InputIterator, class _Allocator>
+ requires(__has_input_iterator_category<_InputIterator>::value && __allocator_ctor_constraint<_Allocator>)
+ _LIBCPP_HIDE_FROM_ABI
+ flat_multimap(sorted_equivalent_t, _InputIterator __first, _InputIterator __last, const _Allocator& __alloc)
+ : flat_multimap(__ctor_uses_allocator_empty_tag{}, __alloc) {
+ insert(sorted_equivalent, __first, __last);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI flat_multimap(initializer_list<value_type> __il, const key_compare& __comp = key_compare())
+ : flat_multimap(__il.begin(), __il.end(), __comp) {}
+
+ template <class _Allocator>
+ requires __allocator_ctor_constraint<_Allocator>
+ _LIBCPP_HIDE_FROM_ABI
+ flat_multimap(initializer_list<value_type> __il, const key_compare& __comp, const _Allocator& __alloc)
+ : flat_multimap(__il.begin(), __il.end(), __comp, __alloc) {}
+
+ template <class _Allocator>
+ requires __allocator_ctor_constraint<_Allocator>
+ _LIBCPP_HIDE_FROM_ABI flat_multimap(initializer_list<value_type> __il, const _Allocator& __alloc)
+ : flat_multimap(__il.begin(), __il.end(), __alloc) {}
+
+ _LIBCPP_HIDE_FROM_ABI
+ flat_multimap(sorted_equivalent_t, initializer_list<value_type> __il, const key_compare& __comp = key_compare())
+ : flat_multimap(sorted_equivalent, __il.begin(), __il.end(), __comp) {}
+
+ template <class _Allocator>
+ requires __allocator_ctor_constraint<_Allocator>
+ _LIBCPP_HIDE_FROM_ABI flat_multimap(
+ sorted_equivalent_t, initializer_list<value_type> __il, const key_compare& __comp, const _Allocator& __alloc)
+ : flat_multimap(sorted_equivalent, __il.begin(), __il.end(), __comp, __alloc) {}
+
+ template <class _Allocator>
+ requires __allocator_ctor_constraint<_Allocator>
+ _LIBCPP_HIDE_FROM_ABI flat_multimap(sorted_equivalent_t, initializer_list<value_type> __il, const _Allocator& __alloc)
+ : flat_multimap(sorted_equivalent, __il.begin(), __il.end(), __alloc) {}
+
+ _LIBCPP_HIDE_FROM_ABI flat_multimap& operator=(initializer_list<value_type> __il) {
+ clear();
+ insert(__il);
+ return *this;
+ }
+
+ // copy/move assignment are not specified in the spec (defaulted)
+ // but move assignment can potentially leave moved from object in an inconsistent
+ // state if an exception is thrown
+ _LIBCPP_HIDE_FROM_ABI flat_multimap& operator=(const flat_multimap&) = default;
+
+ _LIBCPP_HIDE_FROM_ABI flat_multimap& operator=(flat_multimap&& __other) noexcept(
+ is_nothrow_move_assignable_v<_KeyContainer> && is_nothrow_move_assignable_v<_MappedContainer> &&
+ is_nothrow_move_assignable_v<_Compare>) {
+ auto __clear_other_guard = std::__make_scope_guard([&]() noexcept { __other.clear() /* noexcept */; });
+ auto __clear_self_guard = std::__make_exception_guard([&]() noexcept { clear() /* noexcept */; });
+ __containers_ = std::move(__other.__containers_);
+ __compare_ = std::move(__other.__compare_);
+ __clear_self_guard.__complete();
+ return *this;
+ }
+
+ // iterators
+ _LIBCPP_HIDE_FROM_ABI iterator begin() noexcept {
+ return iterator(__containers_.keys.begin(), __containers_.values.begin());
+ }
+
+ _LIBCPP_HIDE_FROM_ABI const_iterator begin() const noexcept {
+ return const_iterator(__containers_.keys.begin(), __containers_.values.begin());
+ }
+
+ _LIBCPP_HIDE_FROM_ABI iterator end() noexcept {
+ return iterator(__containers_.keys.end(), __containers_.values.end());
+ }
+
+ _LIBCPP_HIDE_FROM_ABI const_iterator end() const noexcept {
+ return const_iterator(__containers_.keys.end(), __containers_.values.end());
+ }
+
+ _LIBCPP_HIDE_FROM_ABI reverse_iterator rbegin() noexcept { return reverse_iterator(end()); }
+ _LIBCPP_HIDE_FROM_ABI const_reverse_iterator rbegin() const noexcept { return const_reverse_iterator(end()); }
+ _LIBCPP_HIDE_FROM_ABI reverse_iterator rend() noexcept { return reverse_iterator(begin()); }
+ _LIBCPP_HIDE_FROM_ABI const_reverse_iterator rend() const noexcept { return const_reverse_iterator(begin()); }
+
+ _LIBCPP_HIDE_FROM_ABI const_iterator cbegin() const noexcept { return begin(); }
+ _LIBCPP_HIDE_FROM_ABI const_iterator cend() const noexcept { return end(); }
+ _LIBCPP_HIDE_FROM_ABI const_reverse_iterator crbegin() const noexcept { return const_reverse_iterator(end()); }
+ _LIBCPP_HIDE_FROM_ABI const_reverse_iterator crend() const noexcept { return const_reverse_iterator(begin()); }
+
+ // [flat.map.capacity], capacity
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI bool empty() const noexcept { return __containers_.keys.empty(); }
+
+ _LIBCPP_HIDE_FROM_ABI size_type size() const noexcept { return __containers_.keys.size(); }
+
+ _LIBCPP_HIDE_FROM_ABI size_type max_size() const noexcept {
+ return std::min<size_type>(__containers_.keys.max_size(), __containers_.values.max_size());
+ }
+
+ // [flat.map.modifiers], modifiers
+ template <class... _Args>
+ requires is_constructible_v<pair<key_type, mapped_type>, _Args...> && is_move_constructible_v<key_type> &&
+ is_move_constructible_v<mapped_type>
+ _LIBCPP_HIDE_FROM_ABI iterator emplace(_Args&&... __args) {
+ std::pair<key_type, mapped_type> __pair(std::forward<_Args>(__args)...);
+ auto __key_it = ranges::upper_bound(__containers_.keys, __pair.first, __compare_);
+ auto __mapped_it = __corresponding_mapped_it(*this, __key_it);
+
+ return __flat_map_utils::__emplace_exact_pos(
+ *this, std::move(__key_it), std::move(__mapped_it), std::move(__pair.first), std::move(__pair.second));
+ }
+
+ template <class... _Args>
+ requires is_constructible_v<pair<key_type, mapped_type>, _Args...>
+ _LIBCPP_HIDE_FROM_ABI iterator emplace_hint(const_iterator __hint, _Args&&... __args) {
+ std::pair<key_type, mapped_type> __pair(std::forward<_Args>(__args)...);
+
+ auto __prev_larger = __hint != cbegin() && __compare_(__pair.first, (__hint - 1)->first);
+ auto __next_smaller = __hint != cend() && __compare_(__hint->first, __pair.first);
+
+ auto __hint_distance = __hint.__key_iter_ - __containers_.keys.cbegin();
+ auto __key_iter = __containers_.keys.begin() + __hint_distance;
+ auto __mapped_iter = __containers_.values.begin() + __hint_distance;
+
+ if (!__prev_larger && !__next_smaller) [[likely]] {
+ // hint correct, just use exact hint iterators
+ } else if (__prev_larger && !__next_smaller) {
+ // the hint position is more to the right than the key should have been.
+ // we want to emplace the element to a position as right as possible
+ // e.g. Insert new element "2" in the following range
+ // 1, 1, 2, 2, 2, 3, 4, 6
+ // ^
+ // |
+ // hint
+ // We want to insert "2" after the last existing "2"
+ __key_iter = ranges::upper_bound(__containers_.keys.begin(), __key_iter, __pair.first, __compare_);
+ __mapped_iter = __corresponding_mapped_it(*this, __key_iter);
+ } else {
+ _LIBCPP_ASSERT_INTERNAL(!__prev_larger && __next_smaller, "this means that the multimap is not sorted");
+
+ // the hint position is more to the left than the key should have been.
+ // we want to emplace the element to a position as left as possible
+ // 1, 1, 2, 2, 2, 3, 4, 6
+ // ^
+ // |
+ // hint
+ // We want to insert "2" before the first existing "2"
+ __key_iter = ranges::lower_bound(__key_iter, __containers_.keys.end(), __pair.first, __compare_);
+ __mapped_iter = __corresponding_mapped_it(*this, __key_iter);
+ }
+ return __flat_map_utils::__emplace_exact_pos(
+ *this, __key_iter, __mapped_iter, std::move(__pair.first), std::move(__pair.second));
+ }
+
+ _LIBCPP_HIDE_FROM_ABI iterator insert(const value_type& __x) { return emplace(__x); }
+
+ _LIBCPP_HIDE_FROM_ABI iterator insert(value_type&& __x) { return emplace(std::move(__x)); }
+
+ _LIBCPP_HIDE_FROM_ABI iterator insert(const_iterator __hint, const value_type& __x) {
+ return emplace_hint(__hint, __x);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI iterator insert(const_iterator __hint, value_type&& __x) {
+ return emplace_hint(__hint, std::move(__x));
+ }
+
+ template <class _PairLike>
+ requires is_constructible_v<pair<key_type, mapped_type>, _PairLike>
+ _LIBCPP_HIDE_FROM_ABI iterator insert(_PairLike&& __x) {
+ return emplace(std::forward<_PairLike>(__x));
+ }
+
+ template <class _PairLike>
+ requires is_constructible_v<pair<key_type, mapped_type>, _PairLike>
+ _LIBCPP_HIDE_FROM_ABI iterator insert(const_iterator __hint, _PairLike&& __x) {
+ return emplace_hint(__hint, std::forward<_PairLike>(__x));
+ }
+
+ template <class _InputIterator>
+ requires __has_input_iterator_category<_InputIterator>::value
+ _LIBCPP_HIDE_FROM_ABI void insert(_InputIterator __first, _InputIterator __last) {
+ if constexpr (sized_sentinel_for<_InputIterator, _InputIterator>) {
+ __reserve(__last - __first);
+ }
+ __append_sort_merge</*WasSorted = */ false>(std::move(__first), std::move(__last));
+ }
+
+ template <class _InputIterator>
+ requires __has_input_iterator_category<_InputIterator>::value
+ _LIBCPP_HIDE_FROM_ABI void insert(sorted_equivalent_t, _InputIterator __first, _InputIterator __last) {
+ if constexpr (sized_sentinel_for<_InputIterator, _InputIterator>) {
+ __reserve(__last - __first);
+ }
+
+ __append_sort_merge</*WasSorted = */ true>(std::move(__first), std::move(__last));
+ }
+
+ template <_ContainerCompatibleRange<value_type> _Range>
+ _LIBCPP_HIDE_FROM_ABI void insert_range(_Range&& __range) {
+ if constexpr (ranges::sized_range<_Range>) {
+ __reserve(ranges::size(__range));
+ }
+
+ __append_sort_merge</*WasSorted = */ false>(ranges::begin(__range), ranges::end(__range));
+ }
+
+ _LIBCPP_HIDE_FROM_ABI void insert(initializer_list<value_type> __il) { insert(__il.begin(), __il.end()); }
+
+ _LIBCPP_HIDE_FROM_ABI void insert(sorted_equivalent_t, initializer_list<value_type> __il) {
+ insert(sorted_equivalent, __il.begin(), __il.end());
+ }
+
+ _LIBCPP_HIDE_FROM_ABI containers extract() && {
+ auto __guard = std::__make_scope_guard([&]() noexcept { clear() /* noexcept */; });
+ auto __ret = std::move(__containers_);
+ return __ret;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI void replace(key_container_type&& __key_cont, mapped_container_type&& __mapped_cont) {
+ _LIBCPP_ASSERT_VALID_INPUT_RANGE(
+ __key_cont.size() == __mapped_cont.size(), "flat_multimap keys and mapped containers have different size");
+
+ _LIBCPP_ASSERT_SEMANTIC_REQUIREMENT(__is_sorted(__key_cont), "Key container is not sorted");
+ auto __guard = std::__make_exception_guard([&]() noexcept { clear() /* noexcept */; });
+ __containers_.keys = std::move(__key_cont);
+ __containers_.values = std::move(__mapped_cont);
+ __guard.__complete();
+ }
+
+ _LIBCPP_HIDE_FROM_ABI iterator erase(iterator __position) {
+ return __erase(__position.__key_iter_, __position.__mapped_iter_);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI iterator erase(const_iterator __position) {
+ return __erase(__position.__key_iter_, __position.__mapped_iter_);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI size_type erase(const key_type& __x) {
+ auto [__first, __last] = equal_range(__x);
+ auto __res = __last - __first;
+ erase(__first, __last);
+ return __res;
+ }
+
+ template <class _Kp>
+ requires(__is_compare_transparent && !is_convertible_v<_Kp &&, iterator> &&
+ !is_convertible_v<_Kp &&, const_iterator>)
+ _LIBCPP_HIDE_FROM_ABI size_type erase(_Kp&& __x) {
+ auto [__first, __last] = equal_range(__x);
+ auto __res = __last - __first;
+ erase(__first, __last);
+ return __res;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI iterator erase(const_iterator __first, const_iterator __last) {
+ auto __on_failure = std::__make_exception_guard([&]() noexcept { clear() /* noexcept */; });
+ auto __key_it = __containers_.keys.erase(__first.__key_iter_, __last.__key_iter_);
+ auto __mapped_it = __containers_.values.erase(__first.__mapped_iter_, __last.__mapped_iter_);
+ __on_failure.__complete();
+ return iterator(std::move(__key_it), std::move(__mapped_it));
+ }
+
+ _LIBCPP_HIDE_FROM_ABI void swap(flat_multimap& __y) noexcept {
+ // warning: The spec has unconditional noexcept, which means that
+ // if any of the following functions throw an exception,
+ // std::terminate will be called
+ ranges::swap(__compare_, __y.__compare_);
+ ranges::swap(__containers_.keys, __y.__containers_.keys);
+ ranges::swap(__containers_.values, __y.__containers_.values);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI void clear() noexcept {
+ __containers_.keys.clear();
+ __containers_.values.clear();
+ }
+
+ // observers
+ _LIBCPP_HIDE_FROM_ABI key_compare key_comp() const { return __compare_; }
+ _LIBCPP_HIDE_FROM_ABI value_compare value_comp() const { return value_compare(__compare_); }
+
+ _LIBCPP_HIDE_FROM_ABI const key_container_type& keys() const noexcept { return __containers_.keys; }
+ _LIBCPP_HIDE_FROM_ABI const mapped_container_type& values() const noexcept { return __containers_.values; }
+
+ // map operations
+ _LIBCPP_HIDE_FROM_ABI iterator find(const key_type& __x) { return __find_impl(*this, __x); }
+
+ _LIBCPP_HIDE_FROM_ABI const_iterator find(const key_type& __x) const { return __find_impl(*this, __x); }
+
+ template <class _Kp>
+ requires __is_compare_transparent
+ _LIBCPP_HIDE_FROM_ABI iterator find(const _Kp& __x) {
+ return __find_impl(*this, __x);
+ }
+
+ template <class _Kp>
+ requires __is_compare_transparent
+ _LIBCPP_HIDE_FROM_ABI const_iterator find(const _Kp& __x) const {
+ return __find_impl(*this, __x);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI size_type count(const key_type& __x) const {
+ auto [__first, __last] = equal_range(__x);
+ return __last - __first;
+ }
+
+ template <class _Kp>
+ requires __is_compare_transparent
+ _LIBCPP_HIDE_FROM_ABI size_type count(const _Kp& __x) const {
+ auto [__first, __last] = equal_range(__x);
+ return __last - __first;
+ }
+
+ _LIBCPP_HIDE_FROM_ABI bool contains(const key_type& __x) const { return find(__x) != end(); }
+
+ template <class _Kp>
+ requires __is_compare_transparent
+ _LIBCPP_HIDE_FROM_ABI bool contains(const _Kp& __x) const {
+ return find(__x) != end();
+ }
+
+ _LIBCPP_HIDE_FROM_ABI iterator lower_bound(const key_type& __x) { return __lower_bound<iterator>(*this, __x); }
+
+ _LIBCPP_HIDE_FROM_ABI const_iterator lower_bound(const key_type& __x) const {
+ return __lower_bound<const_iterator>(*this, __x);
+ }
+
+ template <class _Kp>
+ requires __is_compare_transparent
+ _LIBCPP_HIDE_FROM_ABI iterator lower_bound(const _Kp& __x) {
+ return __lower_bound<iterator>(*this, __x);
+ }
+
+ template <class _Kp>
+ requires __is_compare_transparent
+ _LIBCPP_HIDE_FROM_ABI const_iterator lower_bound(const _Kp& __x) const {
+ return __lower_bound<const_iterator>(*this, __x);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI iterator upper_bound(const key_type& __x) { return __upper_bound<iterator>(*this, __x); }
+
+ _LIBCPP_HIDE_FROM_ABI const_iterator upper_bound(const key_type& __x) const {
+ return __upper_bound<const_iterator>(*this, __x);
+ }
+
+ template <class _Kp>
+ requires __is_compare_transparent
+ _LIBCPP_HIDE_FROM_ABI iterator upper_bound(const _Kp& __x) {
+ return __upper_bound<iterator>(*this, __x);
+ }
+
+ template <class _Kp>
+ requires __is_compare_transparent
+ _LIBCPP_HIDE_FROM_ABI const_iterator upper_bound(const _Kp& __x) const {
+ return __upper_bound<const_iterator>(*this, __x);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI pair<iterator, iterator> equal_range(const key_type& __x) {
+ return __equal_range_impl(*this, __x);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI pair<const_iterator, const_iterator> equal_range(const key_type& __x) const {
+ return __equal_range_impl(*this, __x);
+ }
+
+ template <class _Kp>
+ requires __is_compare_transparent
+ _LIBCPP_HIDE_FROM_ABI pair<iterator, iterator> equal_range(const _Kp& __x) {
+ return __equal_range_impl(*this, __x);
+ }
+ template <class _Kp>
+ requires __is_compare_transparent
+ _LIBCPP_HIDE_FROM_ABI pair<const_iterator, const_iterator> equal_range(const _Kp& __x) const {
+ return __equal_range_impl(*this, __x);
+ }
+
+ friend _LIBCPP_HIDE_FROM_ABI bool operator==(const flat_multimap& __x, const flat_multimap& __y) {
+ return ranges::equal(__x, __y);
+ }
+
+ friend _LIBCPP_HIDE_FROM_ABI auto operator<=>(const flat_multimap& __x, const flat_multimap& __y) {
+ return std::lexicographical_compare_three_way(
+ __x.begin(), __x.end(), __y.begin(), __y.end(), std::__synth_three_way);
+ }
+
+ friend _LIBCPP_HIDE_FROM_ABI void swap(flat_multimap& __x, flat_multimap& __y) noexcept { __x.swap(__y); }
+
+private:
+ struct __ctor_uses_allocator_tag {
+ explicit _LIBCPP_HIDE_FROM_ABI __ctor_uses_allocator_tag() = default;
+ };
+ struct __ctor_uses_allocator_empty_tag {
+ explicit _LIBCPP_HIDE_FROM_ABI __ctor_uses_allocator_empty_tag() = default;
+ };
+
+ template <class _Allocator, class _KeyCont, class _MappedCont, class... _CompArg>
+ requires __allocator_ctor_constraint<_Allocator>
+ _LIBCPP_HIDE_FROM_ABI
+ flat_multimap(__ctor_uses_allocator_tag,
+ const _Allocator& __alloc,
+ _KeyCont&& __key_cont,
+ _MappedCont&& __mapped_cont,
+ _CompArg&&... __comp)
+ : __containers_{.keys = std::make_obj_using_allocator<key_container_type>(
+ __alloc, std::forward<_KeyCont>(__key_cont)),
+ .values = std::make_obj_using_allocator<mapped_container_type>(
+ __alloc, std::forward<_MappedCont>(__mapped_cont))},
+ __compare_(std::forward<_CompArg>(__comp)...) {}
+
+ template <class _Allocator, class... _CompArg>
+ requires __allocator_ctor_constraint<_Allocator>
+ _LIBCPP_HIDE_FROM_ABI flat_multimap(__ctor_uses_allocator_empty_tag, const _Allocator& __alloc, _CompArg&&... __comp)
+ : __containers_{.keys = std::make_obj_using_allocator<key_container_type>(__alloc),
+ .values = std::make_obj_using_allocator<mapped_container_type>(__alloc)},
+ __compare_(std::forward<_CompArg>(__comp)...) {}
+
+ _LIBCPP_HIDE_FROM_ABI bool __is_sorted(auto&& __key_container) const {
+ return ranges::is_sorted(__key_container, __compare_);
+ }
+
+ _LIBCPP_HIDE_FROM_ABI void __sort() {
+ auto __zv = ranges::views::zip(__containers_.keys, __containers_.values);
+ ranges::sort(__zv, __compare_, [](const auto& __p) -> decltype(auto) { return std::get<0>(__p); });
+ }
+
+ template <class _Self, class _KeyIter>
+ _LIBCPP_HIDE_FROM_ABI static auto __corresponding_mapped_it(_Self&& __self, _KeyIter&& __key_iter) {
+ return __self.__containers_.values.begin() +
+ static_cast<ranges::range_difference_t<mapped_container_type>>(
+ ranges::distance(__self.__containers_.keys.begin(), __key_iter));
+ }
+
+ template <bool _WasSorted, class _InputIterator, class _Sentinel>
+ _LIBCPP_HIDE_FROM_ABI void __append_sort_merge(_InputIterator __first, _Sentinel __last) {
+ auto __on_failure = std::__make_exception_guard([&]() noexcept { clear() /* noexcept */; });
+ size_t __num_appended = __flat_map_utils::__append(*this, std::move(__first), std::move(__last));
+ if (__num_appended != 0) {
+ auto __zv = ranges::views::zip(__containers_.keys, __containers_.values);
+ auto __append_start_offset = __containers_.keys.size() - __num_appended;
+ auto __end = __zv.end();
+ auto __compare_key = [this](const auto& __p1, const auto& __p2) {
+ return __compare_(std::get<0>(__p1), std::get<0>(__p2));
+ };
+ if constexpr (!_WasSorted) {
+ ranges::sort(__zv.begin() + __append_start_offset, __end, __compare_key);
+ } else {
+ _LIBCPP_ASSERT_SEMANTIC_REQUIREMENT(
+ __is_sorted(__containers_.keys | ranges::views::drop(__append_start_offset)),
+ "Key container is not sorted");
+ }
+ ranges::inplace_merge(__zv.begin(), __zv.begin() + __append_start_offset, __end, __compare_key);
+ }
+ __on_failure.__complete();
+ }
+
+ template <class _Self, class _Kp>
+ _LIBCPP_HIDE_FROM_ABI static auto __find_impl(_Self&& __self, const _Kp& __key) {
+ auto __it = __self.lower_bound(__key);
+ auto __last = __self.end();
+ if (__it == __last || __self.__compare_(__key, __it->first)) {
+ return __last;
+ }
+ return __it;
+ }
+
+ template <class _Self, class _Kp>
+ _LIBCPP_HIDE_FROM_ABI static auto __equal_range_impl(_Self&& __self, const _Kp& __key) {
+ auto [__key_first, __key_last] = ranges::equal_range(__self.__containers_.keys, __key, __self.__compare_);
+
+ using __iterator_type = ranges::iterator_t<decltype(__self)>;
+ return std::make_pair(__iterator_type(__key_first, __corresponding_mapped_it(__self, __key_first)),
+ __iterator_type(__key_last, __corresponding_mapped_it(__self, __key_last)));
+ }
+
+ template <class _Res, class _Self, class _Kp>
+ _LIBCPP_HIDE_FROM_ABI static _Res __lower_bound(_Self&& __self, _Kp& __x) {
+ auto __key_iter = ranges::lower_bound(__self.__containers_.keys, __x, __self.__compare_);
+ auto __mapped_iter = __corresponding_mapped_it(__self, __key_iter);
+ return _Res(std::move(__key_iter), std::move(__mapped_iter));
+ }
+
+ template <class _Res, class _Self, class _Kp>
+ _LIBCPP_HIDE_FROM_ABI static _Res __upper_bound(_Self&& __self, _Kp& __x) {
+ auto __key_iter = ranges::upper_bound(__self.__containers_.keys, __x, __self.__compare_);
+ auto __mapped_iter = __corresponding_mapped_it(__self, __key_iter);
+ return _Res(std::move(__key_iter), std::move(__mapped_iter));
+ }
+
+ _LIBCPP_HIDE_FROM_ABI void __reserve(size_t __size) {
+ if constexpr (requires { __containers_.keys.reserve(__size); }) {
+ __containers_.keys.reserve(__size);
+ }
+
+ if constexpr (requires { __containers_.values.reserve(__size); }) {
+ __containers_.values.reserve(__size);
+ }
+ }
+
+ template <class _KIter, class _MIter>
+ _LIBCPP_HIDE_FROM_ABI iterator __erase(_KIter __key_iter_to_remove, _MIter __mapped_iter_to_remove) {
+ auto __on_failure = std::__make_exception_guard([&]() noexcept { clear() /* noexcept */; });
+ auto __key_iter = __containers_.keys.erase(__key_iter_to_remove);
+ auto __mapped_iter = __containers_.values.erase(__mapped_iter_to_remove);
+ __on_failure.__complete();
+ return iterator(std::move(__key_iter), std::move(__mapped_iter));
+ }
+
+ template <class _Key2, class _Tp2, class _Compare2, class _KeyContainer2, class _MappedContainer2, class _Predicate>
+ friend typename flat_multimap<_Key2, _Tp2, _Compare2, _KeyContainer2, _MappedContainer2>::size_type
+ erase_if(flat_multimap<_Key2, _Tp2, _Compare2, _KeyContainer2, _MappedContainer2>&, _Predicate);
+
+ friend __flat_map_utils;
+
+ containers __containers_;
+ _LIBCPP_NO_UNIQUE_ADDRESS key_compare __compare_;
+
+ struct __key_equiv {
+ _LIBCPP_HIDE_FROM_ABI __key_equiv(key_compare __c) : __comp_(__c) {}
+ _LIBCPP_HIDE_FROM_ABI bool operator()(const_reference __x, const_reference __y) const {
+ return !__comp_(std::get<0>(__x), std::get<0>(__y)) && !__comp_(std::get<0>(__y), std::get<0>(__x));
+ }
+ key_compare __comp_;
+ };
+};
+
+template <class _KeyContainer, class _MappedContainer, class _Compare = less<typename _KeyContainer::value_type>>
+ requires(!__is_allocator<_Compare>::value && !__is_allocator<_KeyContainer>::value &&
+ !__is_allocator<_MappedContainer>::value &&
+ is_invocable_v<const _Compare&,
+ const typename _KeyContainer::value_type&,
+ const typename _KeyContainer::value_type&>)
+flat_multimap(_KeyContainer, _MappedContainer, _Compare = _Compare())
+ -> flat_multimap<typename _KeyContainer::value_type,
+ typename _MappedContainer::value_type,
+ _Compare,
+ _KeyContainer,
+ _MappedContainer>;
+
+template <class _KeyContainer, class _MappedContainer, class _Allocator>
+ requires(uses_allocator_v<_KeyContainer, _Allocator> && uses_allocator_v<_MappedContainer, _Allocator> &&
+ !__is_allocator<_KeyContainer>::value && !__is_allocator<_MappedContainer>::value)
+flat_multimap(_KeyContainer, _MappedContainer, _Allocator)
+ -> flat_multimap<typename _KeyContainer::value_type,
+ typename _MappedContainer::value_type,
+ less<typename _KeyContainer::value_type>,
+ _KeyContainer,
+ _MappedContainer>;
+
+template <class _KeyContainer, class _MappedContainer, class _Compare, class _Allocator>
+ requires(!__is_allocator<_Compare>::value && !__is_allocator<_KeyContainer>::value &&
+ !__is_allocator<_MappedContainer>::value && uses_allocator_v<_KeyContainer, _Allocator> &&
+ uses_allocator_v<_MappedContainer, _Allocator> &&
+ is_invocable_v<const _Compare&,
+ const typename _KeyContainer::value_type&,
+ const typename _KeyContainer::value_type&>)
+flat_multimap(_KeyContainer, _MappedContainer, _Compare, _Allocator)
+ -> flat_multimap<typename _KeyContainer::value_type,
+ typename _MappedContainer::value_type,
+ _Compare,
+ _KeyContainer,
+ _MappedContainer>;
+
+template <class _KeyContainer, class _MappedContainer, class _Compare = less<typename _KeyContainer::value_type>>
+ requires(!__is_allocator<_Compare>::value && !__is_allocator<_KeyContainer>::value &&
+ !__is_allocator<_MappedContainer>::value &&
+ is_invocable_v<const _Compare&,
+ const typename _KeyContainer::value_type&,
+ const typename _KeyContainer::value_type&>)
+flat_multimap(sorted_equivalent_t, _KeyContainer, _MappedContainer, _Compare = _Compare())
+ -> flat_multimap<typename _KeyContainer::value_type,
+ typename _MappedContainer::value_type,
+ _Compare,
+ _KeyContainer,
+ _MappedContainer>;
+
+template <class _KeyContainer, class _MappedContainer, class _Allocator>
+ requires(uses_allocator_v<_KeyContainer, _Allocator> && uses_allocator_v<_MappedContainer, _Allocator> &&
+ !__is_allocator<_KeyContainer>::value && !__is_allocator<_MappedContainer>::value)
+flat_multimap(sorted_equivalent_t, _KeyContainer, _MappedContainer, _Allocator)
+ -> flat_multimap<typename _KeyContainer::value_type,
+ typename _MappedContainer::value_type,
+ less<typename _KeyContainer::value_type>,
+ _KeyContainer,
+ _MappedContainer>;
+
+template <class _KeyContainer, class _MappedContainer, class _Compare, class _Allocator>
+ requires(!__is_allocator<_Compare>::value && !__is_allocator<_KeyContainer>::value &&
+ !__is_allocator<_MappedContainer>::value && uses_allocator_v<_KeyContainer, _Allocator> &&
+ uses_allocator_v<_MappedContainer, _Allocator> &&
+ is_invocable_v<const _Compare&,
+ const typename _KeyContainer::value_type&,
+ const typename _KeyContainer::value_type&>)
+flat_multimap(sorted_equivalent_t, _KeyContainer, _MappedContainer, _Compare, _Allocator)
+ -> flat_multimap<typename _KeyContainer::value_type,
+ typename _MappedContainer::value_type,
+ _Compare,
+ _KeyContainer,
+ _MappedContainer>;
+
+template <class _InputIterator, class _Compare = less<__iter_key_type<_InputIterator>>>
+ requires(__has_input_iterator_category<_InputIterator>::value && !__is_allocator<_Compare>::value)
+flat_multimap(_InputIterator, _InputIterator, _Compare = _Compare())
+ -> flat_multimap<__iter_key_type<_InputIterator>, __iter_mapped_type<_InputIterator>, _Compare>;
+
+template <class _InputIterator, class _Compare = less<__iter_key_type<_InputIterator>>>
+ requires(__has_input_iterator_category<_InputIterator>::value && !__is_allocator<_Compare>::value)
+flat_multimap(sorted_equivalent_t, _InputIterator, _InputIterator, _Compare = _Compare())
+ -> flat_multimap<__iter_key_type<_InputIterator>, __iter_mapped_type<_InputIterator>, _Compare>;
+
+template <ranges::input_range _Range,
+ class _Compare = less<__range_key_type<_Range>>,
+ class _Allocator = allocator<byte>,
+ class = __enable_if_t<!__is_allocator<_Compare>::value && __is_allocator<_Allocator>::value>>
+flat_multimap(from_range_t, _Range&&, _Compare = _Compare(), _Allocator = _Allocator()) -> flat_multimap<
+ __range_key_type<_Range>,
+ __range_mapped_type<_Range>,
+ _Compare,
+ vector<__range_key_type<_Range>, __allocator_traits_rebind_t<_Allocator, __range_key_type<_Range>>>,
+ vector<__range_mapped_type<_Range>, __allocator_traits_rebind_t<_Allocator, __range_mapped_type<_Range>>>>;
+
+template <ranges::input_range _Range, class _Allocator, class = __enable_if_t<__is_allocator<_Allocator>::value>>
+flat_multimap(from_range_t, _Range&&, _Allocator) -> flat_multimap<
+ __range_key_type<_Range>,
+ __range_mapped_type<_Range>,
+ less<__range_key_type<_Range>>,
+ vector<__range_key_type<_Range>, __allocator_traits_rebind_t<_Allocator, __range_key_type<_Range>>>,
+ vector<__range_mapped_type<_Range>, __allocator_traits_rebind_t<_Allocator, __range_mapped_type<_Range>>>>;
+
+template <class _Key, class _Tp, class _Compare = less<_Key>>
+ requires(!__is_allocator<_Compare>::value)
+flat_multimap(initializer_list<pair<_Key, _Tp>>, _Compare = _Compare()) -> flat_multimap<_Key, _Tp, _Compare>;
+
+template <class _Key, class _Tp, class _Compare = less<_Key>>
+ requires(!__is_allocator<_Compare>::value)
+flat_multimap(sorted_equivalent_t, initializer_list<pair<_Key, _Tp>>, _Compare = _Compare())
+ -> flat_multimap<_Key, _Tp, _Compare>;
+
+template <class _Key, class _Tp, class _Compare, class _KeyContainer, class _MappedContainer, class _Allocator>
+struct uses_allocator<flat_multimap<_Key, _Tp, _Compare, _KeyContainer, _MappedContainer>, _Allocator>
+ : bool_constant<uses_allocator_v<_KeyContainer, _Allocator> && uses_allocator_v<_MappedContainer, _Allocator>> {};
+
+template <class _Key, class _Tp, class _Compare, class _KeyContainer, class _MappedContainer, class _Predicate>
+_LIBCPP_HIDE_FROM_ABI typename flat_multimap<_Key, _Tp, _Compare, _KeyContainer, _MappedContainer>::size_type
+erase_if(flat_multimap<_Key, _Tp, _Compare, _KeyContainer, _MappedContainer>& __flat_multimap, _Predicate __pred) {
+ auto __zv = ranges::views::zip(__flat_multimap.__containers_.keys, __flat_multimap.__containers_.values);
+ auto __first = __zv.begin();
+ auto __last = __zv.end();
+ auto __guard = std::__make_exception_guard([&] { __flat_multimap.clear(); });
+ auto __it = std::remove_if(__first, __last, [&](auto&& __zipped) -> bool {
+ using _Ref = typename flat_multimap<_Key, _Tp, _Compare, _KeyContainer, _MappedContainer>::const_reference;
+ return __pred(_Ref(std::get<0>(__zipped), std::get<1>(__zipped)));
+ });
+ auto __res = __last - __it;
+ auto __offset = __it - __first;
+
+ const auto __erase_container = [&](auto& __cont) { __cont.erase(__cont.begin() + __offset, __cont.end()); };
+
+ __erase_container(__flat_multimap.__containers_.keys);
+ __erase_container(__flat_multimap.__containers_.values);
+
+ __guard.__complete();
+ return __res;
+}
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP_STD_VER >= 23
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___FLAT_MAP_FLAT_MULTIMAP_H
diff --git a/libcxx/include/__flat_map/sorted_equivalent.h b/libcxx/include/__flat_map/sorted_equivalent.h
new file mode 100644
index 0000000000000..1db935cc6ee75
--- /dev/null
+++ b/libcxx/include/__flat_map/sorted_equivalent.h
@@ -0,0 +1,31 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+#ifndef _LIBCPP___FLAT_MAP_SORTED_EQUIVALENT_H
+#define _LIBCPP___FLAT_MAP_SORTED_EQUIVALENT_H
+
+#include <__config>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+#if _LIBCPP_STD_VER >= 23
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+struct sorted_equivalent_t {
+ explicit sorted_equivalent_t() = default;
+};
+inline constexpr sorted_equivalent_t sorted_equivalent{};
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP_STD_VER >= 23
+
+#endif // _LIBCPP___FLAT_MAP_SORTED_EQUIVALENT_H
diff --git a/libcxx/include/__flat_map/utils.h b/libcxx/include/__flat_map/utils.h
new file mode 100644
index 0000000000000..acb7dca7ffe96
--- /dev/null
+++ b/libcxx/include/__flat_map/utils.h
@@ -0,0 +1,103 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___FLAT_MAP_UTILS_H
+#define _LIBCPP___FLAT_MAP_UTILS_H
+
+#include <__config>
+#include <__type_traits/container_traits.h>
+#include <__utility/exception_guard.h>
+#include <__utility/forward.h>
+#include <__utility/move.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+#if _LIBCPP_STD_VER >= 23
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+// These utilities are defined in a class instead of a namespace so that this class can be befriended more easily.
+struct __flat_map_utils {
+ // Emplace a {key: value} into a flat_{multi}map, at the exact position that
+ // __it_key and __it_mapped point to, assuming that the key is not already present in the map.
+ // When an exception is thrown during the emplacement, the function will try its best to
+ // roll back the changes it made to the map. If it cannot roll back the changes, it will
+ // clear the map.
+ template <class _Map, class _IterK, class _IterM, class _KeyArg, class... _MArgs>
+ _LIBCPP_HIDE_FROM_ABI static typename _Map::iterator __emplace_exact_pos(
+ _Map& __map, _IterK&& __it_key, _IterM&& __it_mapped, _KeyArg&& __key, _MArgs&&... __mapped_args) {
+ auto __on_key_failed = std::__make_exception_guard([&]() noexcept {
+ using _KeyContainer = typename _Map::key_container_type;
+ if constexpr (__container_traits<_KeyContainer>::__emplacement_has_strong_exception_safety_guarantee) {
+ // Nothing to roll back!
+ } else {
+ // we need to clear both because we don't know the state of our keys anymore
+ __map.clear() /* noexcept */;
+ }
+ });
+ auto __key_it = __map.__containers_.keys.emplace(__it_key, std::forward<_KeyArg>(__key));
+ __on_key_failed.__complete();
+
+ auto __on_value_failed = std::__make_exception_guard([&]() noexcept {
+ using _MappedContainer = typename _Map::mapped_container_type;
+ if constexpr (!__container_traits<_MappedContainer>::__emplacement_has_strong_exception_safety_guarantee) {
+ // we need to clear both because we don't know the state of our values anymore
+ __map.clear() /* noexcept */;
+ } else {
+ // In this case, we know the values are just like before we attempted emplacement,
+ // and we also know that the keys have been emplaced successfully. Just roll back the keys.
+# if _LIBCPP_HAS_EXCEPTIONS
+ try {
+# endif // _LIBCPP_HAS_EXCEPTIONS
+ __map.__containers_.keys.erase(__key_it);
+# if _LIBCPP_HAS_EXCEPTIONS
+ } catch (...) {
+ // Now things are funky for real. We're failing to rollback the keys.
+ // Just give up and clear the whole thing.
+ //
+ // Also, swallow the exception that happened during the rollback and let the
+ // original value-emplacement exception propagate normally.
+ __map.clear() /* noexcept */;
+ }
+# endif // _LIBCPP_HAS_EXCEPTIONS
+ }
+ });
+ auto __mapped_it = __map.__containers_.values.emplace(__it_mapped, std::forward<_MArgs>(__mapped_args)...);
+ __on_value_failed.__complete();
+
+ return typename _Map::iterator(std::move(__key_it), std::move(__mapped_it));
+ }
+
+ // TODO: We could optimize this, see
+ // https://github.com/llvm/llvm-project/issues/108624
+ template <class _Map, class _InputIterator, class _Sentinel>
+ _LIBCPP_HIDE_FROM_ABI static typename _Map::size_type
+ __append(_Map& __map, _InputIterator __first, _Sentinel __last) {
+ typename _Map::size_type __num_appended = 0;
+ for (; __first != __last; ++__first) {
+ typename _Map::value_type __kv = *__first;
+ __map.__containers_.keys.insert(__map.__containers_.keys.end(), std::move(__kv.first));
+ __map.__containers_.values.insert(__map.__containers_.values.end(), std::move(__kv.second));
+ ++__num_appended;
+ }
+ return __num_appended;
+ }
+};
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP_STD_VER >= 23
+
+_LIBCPP_POP_MACROS
+
+#endif // #define _LIBCPP___FLAT_MAP_UTILS_H
diff --git a/libcxx/include/__functional/is_transparent.h b/libcxx/include/__functional/is_transparent.h
index b2d62f2e3ead8..567df1a662f54 100644
--- a/libcxx/include/__functional/is_transparent.h
+++ b/libcxx/include/__functional/is_transparent.h
@@ -21,11 +21,11 @@ _LIBCPP_BEGIN_NAMESPACE_STD
#if _LIBCPP_STD_VER >= 14
-template <class _Tp, class, class = void>
+template <class _Tp, class _Key = void, class = void>
inline const bool __is_transparent_v = false;
-template <class _Tp, class _Up>
-inline const bool __is_transparent_v<_Tp, _Up, __void_t<typename _Tp::is_transparent> > = true;
+template <class _Tp, class _Key>
+inline const bool __is_transparent_v<_Tp, _Key, __void_t<typename _Tp::is_transparent> > = true;
#endif
diff --git a/libcxx/include/flat_map b/libcxx/include/flat_map
index dbe5d8ee8f8c3..2552450081734 100644
--- a/libcxx/include/flat_map
+++ b/libcxx/include/flat_map
@@ -35,6 +35,25 @@ namespace std {
class Predicate>
typename flat_map<Key, T, Compare, KeyContainer, MappedContainer>::size_type
erase_if(flat_map<Key, T, Compare, KeyContainer, MappedContainer>& c, Predicate pred);
+
+ // [flat.multimap], class template flat_multimap
+ template<class Key, class T, class Compare = less<Key>,
+ class KeyContainer = vector<Key>, class MappedContainer = vector<T>>
+ class flat_multimap;
+
+ struct sorted_equivalent_t { explicit sorted_equivalent_t() = default; };
+ inline constexpr sorted_equivalent_t sorted_equivalent{};
+
+ template<class Key, class T, class Compare, class KeyContainer, class MappedContainer,
+ class Allocator>
+ struct uses_allocator<flat_multimap<Key, T, Compare, KeyContainer, MappedContainer>,
+ Allocator>;
+
+ // [flat.multimap.erasure], erasure for flat_multimap
+ template<class Key, class T, class Compare, class KeyContainer, class MappedContainer,
+ class Predicate>
+ typename flat_multimap<Key, T, Compare, KeyContainer, MappedContainer>::size_type
+ erase_if(flat_multimap<Key, T, Compare, KeyContainer, MappedContainer>& c, Predicate pred);
*/
#if __cplusplus < 201103L && defined(_LIBCPP_USE_FROZEN_CXX03_HEADERS)
@@ -44,6 +63,8 @@ namespace std {
# if _LIBCPP_STD_VER >= 23
# include <__flat_map/flat_map.h>
+# include <__flat_map/flat_multimap.h>
+# include <__flat_map/sorted_equivalent.h>
# include <__flat_map/sorted_unique.h>
# endif
diff --git a/libcxx/include/module.modulemap b/libcxx/include/module.modulemap
index cdac9c883ecab..7f12b8ffcdee6 100644
--- a/libcxx/include/module.modulemap
+++ b/libcxx/include/module.modulemap
@@ -1240,9 +1240,20 @@ module std [system] {
}
module flat_map {
- module flat_map { header "__flat_map/flat_map.h" }
+ module flat_map {
+ header "__flat_map/flat_map.h"
+ export std.vector.vector
+ export std.vector.fwd
+ }
+ module flat_multimap {
+ header "__flat_map/flat_multimap.h"
+ export std.vector.vector
+ export std.vector.fwd
+ }
module key_value_iterator { header "__flat_map/key_value_iterator.h" }
+ module sorted_equivalent { header "__flat_map/sorted_equivalent.h" }
module sorted_unique { header "__flat_map/sorted_unique.h" }
+ module utils { header "__flat_map/utils.h" }
header "flat_map"
export *
diff --git a/libcxx/include/version b/libcxx/include/version
index f5b5e7a906f50..105f56be0f6c8 100644
--- a/libcxx/include/version
+++ b/libcxx/include/version
@@ -101,6 +101,8 @@ __cpp_lib_execution 201902L <execution>
201603L // C++17
__cpp_lib_expected 202211L <expected>
__cpp_lib_filesystem 201703L <filesystem>
+__cpp_lib_flat_map 202207L <flat_map>
+__cpp_lib_flat_set 202207L <flat_set>
__cpp_lib_format 202110L <format>
__cpp_lib_format_path 202403L <filesystem>
__cpp_lib_format_ranges 202207L <format>
@@ -480,6 +482,8 @@ __cpp_lib_void_t 201411L <type_traits>
# define __cpp_lib_constexpr_typeinfo 202106L
# define __cpp_lib_containers_ranges 202202L
# define __cpp_lib_expected 202211L
+# define __cpp_lib_flat_map 202207L
+// # define __cpp_lib_flat_set 202207L
# define __cpp_lib_format_ranges 202207L
// # define __cpp_lib_formatters 202302L
# define __cpp_lib_forward_like 202207L
diff --git a/libcxx/modules/std/flat_map.inc b/libcxx/modules/std/flat_map.inc
index 6a86229bceaba..e9521749dc4a8 100644
--- a/libcxx/modules/std/flat_map.inc
+++ b/libcxx/modules/std/flat_map.inc
@@ -20,8 +20,6 @@ export namespace std {
// [flat.map.erasure], erasure for flat_map
using std::erase_if;
-#endif // _LIBCPP_STD_VER >= 23
-#if 0
// [flat.multimap], class template flat_multimap
using std::flat_multimap;
@@ -29,5 +27,5 @@ export namespace std {
using std::sorted_equivalent_t;
// [flat.multimap.erasure], erasure for flat_multimap
-#endif
+#endif // _LIBCPP_STD_VER >= 23
} // namespace std
diff --git a/libcxx/test/libcxx/containers/containers.adaptors/flat.map/assert.input_range.pass.cpp b/libcxx/test/libcxx/containers/container.adaptors/flat.map/assert.input_range.pass.cpp
similarity index 100%
rename from libcxx/test/libcxx/containers/containers.adaptors/flat.map/assert.input_range.pass.cpp
rename to libcxx/test/libcxx/containers/container.adaptors/flat.map/assert.input_range.pass.cpp
diff --git a/libcxx/test/libcxx/containers/containers.adaptors/flat.map/assert.sorted_unique.pass.cpp b/libcxx/test/libcxx/containers/container.adaptors/flat.map/assert.sorted_unique.pass.cpp
similarity index 100%
rename from libcxx/test/libcxx/containers/containers.adaptors/flat.map/assert.sorted_unique.pass.cpp
rename to libcxx/test/libcxx/containers/container.adaptors/flat.map/assert.sorted_unique.pass.cpp
diff --git a/libcxx/test/libcxx/containers/container.adaptors/flat.multimap/assert.input_range.pass.cpp b/libcxx/test/libcxx/containers/container.adaptors/flat.multimap/assert.input_range.pass.cpp
new file mode 100644
index 0000000000000..504f36fcd00b8
--- /dev/null
+++ b/libcxx/test/libcxx/containers/container.adaptors/flat.multimap/assert.input_range.pass.cpp
@@ -0,0 +1,66 @@
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+// REQUIRES: has-unix-headers
+// UNSUPPORTED: c++03, c++11, c++14, c++17, c++20
+// UNSUPPORTED: libcpp-hardening-mode=none
+// XFAIL: libcpp-hardening-mode=debug && availability-verbose_abort-missing
+
+// <flat_map>
+
+// flat_multimap(key_container_type , mapped_container_type , const key_compare& __comp = key_compare())
+// flat_multimap(const key_container_type& , const mapped_container_type& , const _Allocator& )
+// flat_multimap(const key_container_type& , const mapped_container_type& , const key_compare&, const _Allocator& )
+// void replace(key_container_type&& , mapped_container_type&&)
+//
+
+#include <flat_map>
+#include <functional>
+#include <memory>
+#include <vector>
+
+#include "check_assertion.h"
+
+int main(int, char**) {
+ using M = std::flat_multimap<int, int>;
+
+ TEST_LIBCPP_ASSERT_FAILURE(
+ ([] { M m({1, 2, 3}, {4}); }()), "flat_multimap keys and mapped containers have different size");
+
+ TEST_LIBCPP_ASSERT_FAILURE(([] { M m({1, 2, 3}, {4}, std::less<int>{}); }()),
+ "flat_multimap keys and mapped containers have different size");
+
+ TEST_LIBCPP_ASSERT_FAILURE(
+ ([] {
+ const std::vector keys{1, 2, 3};
+ const std::vector values{4};
+ const std::allocator<int> alloc{};
+ M m(keys, values, alloc);
+ }()),
+ "flat_multimap keys and mapped containers have different size");
+
+ TEST_LIBCPP_ASSERT_FAILURE(
+ ([] {
+ const std::vector keys{1, 2, 3};
+ const std::vector values{4};
+ const std::less<int> key_compare{};
+ const std::allocator<int> alloc{};
+ M m(keys, values, key_compare, alloc);
+ }()),
+ "flat_multimap keys and mapped containers have different size");
+
+ TEST_LIBCPP_ASSERT_FAILURE(
+ ([] {
+ std::vector keys{1, 2, 3};
+ std::vector values{4};
+ M m;
+ m.replace(std::move(keys), std::move(values));
+ }()),
+ "flat_multimap keys and mapped containers have different size");
+
+ return 0;
+}
diff --git a/libcxx/test/libcxx/containers/container.adaptors/flat.multimap/assert.sorted_equivalent.pass.cpp b/libcxx/test/libcxx/containers/container.adaptors/flat.multimap/assert.sorted_equivalent.pass.cpp
new file mode 100644
index 0000000000000..6b8ad3c7ac9aa
--- /dev/null
+++ b/libcxx/test/libcxx/containers/container.adaptors/flat.multimap/assert.sorted_equivalent.pass.cpp
@@ -0,0 +1,225 @@
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+// REQUIRES: has-unix-headers
+// UNSUPPORTED: c++03, c++11, c++14, c++17, c++20
+// UNSUPPORTED: libcpp-hardening-mode=none
+// REQUIRES: libcpp-hardening-mode=debug
+// XFAIL: libcpp-hardening-mode=debug && availability-verbose_abort-missing
+
+// <flat_map>
+
+// flat_multimap(key_container_type , mapped_container_type , const key_compare& __comp = key_compare())
+// flat_multimap(const key_container_type& , const mapped_container_type& , const _Allocator& )
+// flat_multimap(const key_container_type& , const mapped_container_type& , const key_compare&, const _Allocator& )
+// void replace(key_container_type&& , mapped_container_type&&)
+//
+
+#include <flat_map>
+#include <functional>
+#include <initializer_list>
+#include <memory>
+#include <utility>
+#include <vector>
+
+#include "check_assertion.h"
+
+int main(int, char**) {
+ using M = std::flat_multimap<int, int>;
+
+ TEST_LIBCPP_ASSERT_FAILURE(
+ ([] { M m(std::sorted_equivalent, {2, 2, 1}, {4, 5, 6}); }()), "Key container is not sorted");
+
+ TEST_LIBCPP_ASSERT_FAILURE(
+ ([] { M m(std::sorted_equivalent, {4, 2, 3}, {4, 5, 6}); }()), "Key container is not sorted");
+
+ TEST_LIBCPP_ASSERT_FAILURE(
+ ([] { M m(std::sorted_equivalent, {2, 2, 1}, {4, 5, 6}, std::less<int>{}); }()), "Key container is not sorted");
+
+ TEST_LIBCPP_ASSERT_FAILURE(
+ ([] { M m(std::sorted_equivalent, {4, 2, 3}, {4, 5, 6}, std::less<int>{}); }()), "Key container is not sorted");
+
+ TEST_LIBCPP_ASSERT_FAILURE(
+ ([] {
+ const std::vector keys{2, 2, 1};
+ const std::vector values{4, 5, 6};
+ const std::allocator<int> alloc{};
+ M m(std::sorted_equivalent, keys, values, alloc);
+ }()),
+ "Key container is not sorted");
+
+ TEST_LIBCPP_ASSERT_FAILURE(
+ ([] {
+ const std::vector keys{4, 2, 3};
+ const std::vector values{4, 5, 6};
+ const std::allocator<int> alloc{};
+ M m(std::sorted_equivalent, keys, values, alloc);
+ }()),
+ "Key container is not sorted");
+
+ TEST_LIBCPP_ASSERT_FAILURE(
+ ([] {
+ const std::vector keys{2, 2, 1};
+ const std::vector values{4, 5, 6};
+ const std::allocator<int> alloc{};
+ const std::less<int> comp{};
+ M m(std::sorted_equivalent, keys, values, comp, alloc);
+ }()),
+ "Key container is not sorted");
+
+ TEST_LIBCPP_ASSERT_FAILURE(
+ ([] {
+ const std::vector keys{4, 2, 3};
+ const std::vector values{4, 5, 6};
+ const std::allocator<int> alloc{};
+ const std::less<int> comp{};
+ M m(std::sorted_equivalent, keys, values, comp, alloc);
+ }()),
+ "Key container is not sorted");
+
+ TEST_LIBCPP_ASSERT_FAILURE(
+ ([] {
+ const std::vector<std::pair<int, int>> v{{2, 4}, {2, 5}, {1, 6}};
+ const std::less<int> comp{};
+ M m(std::sorted_equivalent, v.begin(), v.end(), comp);
+ }()),
+ "Key container is not sorted");
+
+ TEST_LIBCPP_ASSERT_FAILURE(
+ ([] {
+ const std::vector<std::pair<int, int>> v{{4, 4}, {2, 5}, {3, 6}};
+ const std::less<int> comp{};
+ M m(std::sorted_equivalent, v.begin(), v.end(), comp);
+ }()),
+ "Key container is not sorted");
+
+ TEST_LIBCPP_ASSERT_FAILURE(
+ ([] {
+ const std::vector<std::pair<int, int>> v{{2, 4}, {2, 5}, {1, 6}};
+ const std::less<int> comp{};
+ const std::allocator<int> alloc{};
+ M m(std::sorted_equivalent, v.begin(), v.end(), comp, alloc);
+ }()),
+ "Key container is not sorted");
+
+ TEST_LIBCPP_ASSERT_FAILURE(
+ ([] {
+ const std::vector<std::pair<int, int>> v{{4, 4}, {2, 5}, {3, 6}};
+ const std::less<int> comp{};
+ const std::allocator<int> alloc{};
+ M m(std::sorted_equivalent, v.begin(), v.end(), comp, alloc);
+ }()),
+ "Key container is not sorted");
+
+ TEST_LIBCPP_ASSERT_FAILURE(
+ ([] {
+ const std::vector<std::pair<int, int>> v{{2, 4}, {2, 5}, {1, 6}};
+ const std::allocator<int> alloc{};
+ M m(std::sorted_equivalent, v.begin(), v.end(), alloc);
+ }()),
+ "Key container is not sorted");
+
+ TEST_LIBCPP_ASSERT_FAILURE(
+ ([] {
+ const std::vector<std::pair<int, int>> v{{4, 4}, {2, 5}, {3, 6}};
+ const std::allocator<int> alloc{};
+ M m(std::sorted_equivalent, v.begin(), v.end(), alloc);
+ }()),
+ "Key container is not sorted");
+
+ TEST_LIBCPP_ASSERT_FAILURE(
+ ([] {
+ std::initializer_list<std::pair<int, int>> v{{2, 4}, {2, 5}, {1, 6}};
+ const std::less<int> comp{};
+ M m(std::sorted_equivalent, v, comp);
+ }()),
+ "Key container is not sorted");
+
+ TEST_LIBCPP_ASSERT_FAILURE(
+ ([] {
+ std::initializer_list<std::pair<int, int>> v{{4, 4}, {2, 5}, {3, 6}};
+ const std::less<int> comp{};
+ M m(std::sorted_equivalent, v, comp);
+ }()),
+ "Key container is not sorted");
+
+ TEST_LIBCPP_ASSERT_FAILURE(
+ ([] {
+ std::initializer_list<std::pair<int, int>> v{{2, 4}, {2, 5}, {1, 6}};
+ const std::less<int> comp{};
+ const std::allocator<int> alloc{};
+ M m(std::sorted_equivalent, v, comp, alloc);
+ }()),
+ "Key container is not sorted");
+
+ TEST_LIBCPP_ASSERT_FAILURE(
+ ([] {
+ std::initializer_list<std::pair<int, int>> v{{4, 4}, {2, 5}, {3, 6}};
+ const std::less<int> comp{};
+ const std::allocator<int> alloc{};
+ M m(std::sorted_equivalent, v, comp, alloc);
+ }()),
+ "Key container is not sorted");
+
+ TEST_LIBCPP_ASSERT_FAILURE(
+ ([] {
+ std::initializer_list<std::pair<int, int>> v{{2, 4}, {2, 5}, {1, 6}};
+ const std::allocator<int> alloc{};
+ M m(std::sorted_equivalent, v, alloc);
+ }()),
+ "Key container is not sorted");
+
+ TEST_LIBCPP_ASSERT_FAILURE(
+ ([] {
+ std::initializer_list<std::pair<int, int>> v{{4, 4}, {2, 5}, {3, 6}};
+ const std::allocator<int> alloc{};
+ M m(std::sorted_equivalent, v, alloc);
+ }()),
+ "Key container is not sorted");
+
+ TEST_LIBCPP_ASSERT_FAILURE(
+ ([] {
+ const std::vector<std::pair<int, int>> v{{2, 4}, {2, 5}, {1, 6}};
+ M m;
+ m.insert(std::sorted_equivalent, v.begin(), v.end());
+ }()),
+ "Key container is not sorted");
+
+ TEST_LIBCPP_ASSERT_FAILURE(
+ ([] {
+ const std::vector<std::pair<int, int>> v{{4, 4}, {2, 5}, {3, 6}};
+ M m;
+ m.insert(std::sorted_equivalent, v.begin(), v.end());
+ }()),
+ "Key container is not sorted");
+
+ TEST_LIBCPP_ASSERT_FAILURE(
+ ([] {
+ std::initializer_list<std::pair<int, int>> v{{2, 4}, {2, 5}, {1, 6}};
+ M m;
+ m.insert(std::sorted_equivalent, v);
+ }()),
+ "Key container is not sorted");
+
+ TEST_LIBCPP_ASSERT_FAILURE(
+ ([] {
+ std::initializer_list<std::pair<int, int>> v{{4, 4}, {2, 5}, {3, 6}};
+ M m;
+ m.insert(std::sorted_equivalent, v);
+ }()),
+ "Key container is not sorted");
+
+ TEST_LIBCPP_ASSERT_FAILURE(
+ ([] {
+ std::vector keys{2, 1, 3};
+ std::vector values{4, 5, 6};
+ M m;
+ m.replace(std::move(keys), std::move(values));
+ }()),
+ "Key container is not sorted");
+ return 0;
+}
diff --git a/libcxx/test/std/containers/container.adaptors/flat.map.syn/sorted_equivalent.pass.cpp b/libcxx/test/std/containers/container.adaptors/flat.map.syn/sorted_equivalent.pass.cpp
new file mode 100644
index 0000000000000..d9ee3fbd287b5
--- /dev/null
+++ b/libcxx/test/std/containers/container.adaptors/flat.map.syn/sorted_equivalent.pass.cpp
@@ -0,0 +1,50 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+// UNSUPPORTED: c++03, c++11, c++14, c++17, c++20
+
+// <flat_map>
+
+// struct sorted_equivalent_t { explicit sorted_equivalent_t() = default; };
+// inline constexpr sorted_equivalent_t sorted_equivalent{};
+
+#include <cassert>
+#include <concepts>
+#include <flat_map>
+#include <type_traits>
+
+template <class T>
+void implicit_test(T) {}
+
+template <class T>
+concept HasImplicitDefaultCtor = requires { implicit_test<T>({}); };
+
+static_assert(std::is_default_constructible_v<std::sorted_equivalent_t>);
+static_assert(std::is_trivially_default_constructible_v<std::sorted_equivalent_t>);
+static_assert(!HasImplicitDefaultCtor<std::sorted_equivalent_t>);
+
+constexpr bool test() {
+ {
+ [[maybe_unused]] std::sorted_equivalent_t s;
+ }
+ {
+ [[maybe_unused]] std::same_as<const std::sorted_equivalent_t&> decltype(auto) s = (std::sorted_equivalent);
+ }
+ {
+ [[maybe_unused]] std::same_as<const std::sorted_equivalent_t> decltype(auto) copy = std::sorted_equivalent;
+ }
+
+ return true;
+}
+
+int main(int, char**) {
+ test();
+ static_assert(test());
+
+ return 0;
+}
diff --git a/libcxx/test/std/containers/container.adaptors/flat.map/flat.map.capacity/empty.pass.cpp b/libcxx/test/std/containers/container.adaptors/flat.map/flat.map.capacity/empty.pass.cpp
index 5ecc2cf7c917b..05efe063c1e17 100644
--- a/libcxx/test/std/containers/container.adaptors/flat.map/flat.map.capacity/empty.pass.cpp
+++ b/libcxx/test/std/containers/container.adaptors/flat.map/flat.map.capacity/empty.pass.cpp
@@ -25,7 +25,9 @@
template <class KeyContainer, class ValueContainer>
void test() {
- using M = std::flat_map<int, double, std::less<int>, KeyContainer, ValueContainer>;
+ using Key = typename KeyContainer::value_type;
+ using Value = typename ValueContainer::value_type;
+ using M = std::flat_multimap<Key, Value, std::less<int>, KeyContainer, ValueContainer>;
M m;
ASSERT_SAME_TYPE(decltype(m.empty()), bool);
ASSERT_NOEXCEPT(m.empty());
diff --git a/libcxx/test/std/containers/container.adaptors/flat.map/flat.map.capacity/empty.verify.cpp b/libcxx/test/std/containers/container.adaptors/flat.map/flat.map.capacity/empty.verify.cpp
index cc8016182dcb6..79b943b790d04 100644
--- a/libcxx/test/std/containers/container.adaptors/flat.map/flat.map.capacity/empty.verify.cpp
+++ b/libcxx/test/std/containers/container.adaptors/flat.map/flat.map.capacity/empty.verify.cpp
@@ -14,11 +14,7 @@
#include <flat_map>
-#include "test_macros.h"
-
-int main(int, char**) {
+void f() {
std::flat_map<int, int> c;
c.empty(); // expected-warning {{ignoring return value of function declared with 'nodiscard' attribute}}
-
- return 0;
}
diff --git a/libcxx/test/std/containers/container.adaptors/flat.map/flat.map.cons/deduct.compile.pass.cpp b/libcxx/test/std/containers/container.adaptors/flat.map/flat.map.cons/deduct.compile.pass.cpp
new file mode 100644
index 0000000000000..190d78f927f34
--- /dev/null
+++ b/libcxx/test/std/containers/container.adaptors/flat.map/flat.map.cons/deduct.compile.pass.cpp
@@ -0,0 +1,52 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+// UNSUPPORTED: c++03, c++11, c++14, c++17, c++20
+
+// <flat_map>
+
+// Test CTAD on cases where deduction should fail.
+
+#include <flat_map>
+#include <functional>
+#include <memory>
+#include <utility>
+#include <vector>
+
+struct NotAnAllocator {
+ friend bool operator<(NotAnAllocator, NotAnAllocator) { return false; }
+};
+
+using P = std::pair<int, long>;
+using PC = std::pair<const int, long>;
+
+template <class... Args>
+concept CanDeductFlatMap = requires { std::flat_map{std::declval<Args>()...}; };
+
+static_assert(CanDeductFlatMap<std::vector<int>, std::vector<int>>);
+
+// cannot deduce Key and T from nothing
+static_assert(!CanDeductFlatMap<>);
+
+// cannot deduce Key and T from just (KeyContainer), even if it's a container of pairs
+static_assert(!CanDeductFlatMap<std::vector<std::pair<int, int>>>);
+
+// cannot deduce Key and T from just (KeyContainer, Allocator)
+static_assert(!CanDeductFlatMap<std::vector<int>, std::allocator<std::pair<const int, int>>>);
+
+// cannot deduce Key and T from just (Compare)
+static_assert(!CanDeductFlatMap<std::less<int>>);
+
+// cannot deduce Key and T from just (Compare, Allocator)
+static_assert(!CanDeductFlatMap<std::less<int>, std::allocator<PC>>);
+
+// cannot deduce Key and T from just (Allocator)
+static_assert(!CanDeductFlatMap<std::allocator<PC>>);
+
+// cannot convert from some arbitrary unrelated type
+static_assert(!CanDeductFlatMap<NotAnAllocator>);
diff --git a/libcxx/test/std/containers/container.adaptors/flat.map/flat.map.cons/deduct.pass.cpp b/libcxx/test/std/containers/container.adaptors/flat.map/flat.map.cons/deduct.pass.cpp
index d01bee9aae9c0..009392feb3862 100644
--- a/libcxx/test/std/containers/container.adaptors/flat.map/flat.map.cons/deduct.pass.cpp
+++ b/libcxx/test/std/containers/container.adaptors/flat.map/flat.map.cons/deduct.pass.cpp
@@ -169,6 +169,24 @@ void test_iter_iter() {
std::flat_map m(mo.cbegin(), mo.cend());
ASSERT_SAME_TYPE(decltype(m), decltype(mo));
}
+ {
+ std::pair<int, int> source[3] = {{1, 1}, {2, 2}, {3, 3}};
+ std::flat_map s = {source, source + 3}; // flat_map(InputIterator, InputIterator)
+ ASSERT_SAME_TYPE(decltype(s), std::flat_map<int, int>);
+ assert(s.size() == 3);
+ }
+ {
+ std::pair<int, int> source[3] = {{1, 1}, {2, 2}, {3, 3}};
+ std::flat_map s{source, source + 3}; // flat_map(InputIterator, InputIterator)
+ ASSERT_SAME_TYPE(decltype(s), std::flat_map<int, int>);
+ assert(s.size() == 3);
+ }
+ {
+ std::pair<int, int> source[3] = {{1, 1}, {2, 2}, {3, 3}};
+ std::flat_map s{std::sorted_unique, source, source + 3}; // flat_map(sorted_unique_t, InputIterator, InputIterator)
+ static_assert(std::is_same_v<decltype(s), std::flat_map<int, int>>);
+ assert(s.size() == 3);
+ }
}
void test_iter_iter_compare() {
@@ -227,6 +245,19 @@ void test_initializer_list() {
ASSERT_SAME_TYPE(decltype(m), std::flat_map<int, long>);
assert(std::ranges::equal(m, sorted_arr));
}
+ {
+ std::flat_map s = {std::make_pair(1, 'a')}; // flat_map(initializer_list<pair<int, char>>)
+ ASSERT_SAME_TYPE(decltype(s), std::flat_map<int, char>);
+ assert(s.size() == 1);
+ }
+ {
+ using M = std::flat_map<int, short>;
+ M m;
+ std::flat_map s = {std::make_pair(m, m)}; // flat_map(initializer_list<pair<M, M>>)
+ ASSERT_SAME_TYPE(decltype(s), std::flat_map<M, M>);
+ assert(s.size() == 1);
+ assert(s[m] == m);
+ }
}
void test_initializer_list_compare() {
@@ -305,38 +336,6 @@ int main(int, char**) {
test_from_range_compare();
AssociativeContainerDeductionGuidesSfinaeAway<std::flat_map, std::flat_map<int, short>>();
- {
- std::flat_map s = {std::make_pair(1, 'a')}; // flat_map(initializer_list<pair<int, char>>)
- ASSERT_SAME_TYPE(decltype(s), std::flat_map<int, char>);
- assert(s.size() == 1);
- }
- {
- using M = std::flat_map<int, short>;
- M m;
- std::flat_map s = {std::make_pair(m, m)}; // flat_map(initializer_list<pair<M, M>>)
- ASSERT_SAME_TYPE(decltype(s), std::flat_map<M, M>);
- assert(s.size() == 1);
- assert(s[m] == m);
- }
-
- {
- std::pair<int, int> source[3] = {{1, 1}, {2, 2}, {3, 3}};
- std::flat_map s = {source, source + 3}; // flat_map(InputIterator, InputIterator)
- ASSERT_SAME_TYPE(decltype(s), std::flat_map<int, int>);
- assert(s.size() == 3);
- }
- {
- std::pair<int, int> source[3] = {{1, 1}, {2, 2}, {3, 3}};
- std::flat_map s{source, source + 3}; // flat_map(InputIterator, InputIterator)
- ASSERT_SAME_TYPE(decltype(s), std::flat_map<int, int>);
- assert(s.size() == 3);
- }
- {
- std::pair<int, int> source[3] = {{1, 1}, {2, 2}, {3, 3}};
- std::flat_map s{std::sorted_unique, source, source + 3}; // flat_map(sorted_unique_t, InputIterator, InputIterator)
- static_assert(std::is_same_v<decltype(s), std::flat_map<int, int>>);
- assert(s.size() == 3);
- }
return 0;
}
diff --git a/libcxx/test/std/containers/container.adaptors/flat.map/flat.map.cons/deduct.verify.cpp b/libcxx/test/std/containers/container.adaptors/flat.map/flat.map.cons/deduct.verify.cpp
index 08244f01cb24e..ed20c1ae715b8 100644
--- a/libcxx/test/std/containers/container.adaptors/flat.map/flat.map.cons/deduct.verify.cpp
+++ b/libcxx/test/std/containers/container.adaptors/flat.map/flat.map.cons/deduct.verify.cpp
@@ -14,56 +14,12 @@
#include <flat_map>
#include <functional>
-#include <memory>
#include <utility>
-#include <vector>
-
-struct NotAnAllocator {
- friend bool operator<(NotAnAllocator, NotAnAllocator) { return false; }
-};
using P = std::pair<int, long>;
using PC = std::pair<const int, long>;
void test() {
- {
- // cannot deduce Key and T from just (KeyContainer), even if it's a container of pairs
- std::vector<std::pair<int, int>> v;
- std::flat_map s(v);
- // expected-error-re@-1{{{{no viable constructor or deduction guide for deduction of template arguments of '.*flat_map'}}}}
- }
- {
- // cannot deduce Key and T from just (KeyContainer, Allocator)
- std::vector<int> v;
- std::flat_map s(v, std::allocator<std::pair<const int, int>>());
- // expected-error-re@-1{{{{no viable constructor or deduction guide for deduction of template arguments of '.*flat_map'}}}}
- }
- {
- // cannot deduce Key and T from nothing
- std::flat_map m;
- // expected-error-re@-1{{{{no viable constructor or deduction guide for deduction of template arguments of '.*flat_map'}}}}
- }
- {
- // cannot deduce Key and T from just (Compare)
- std::flat_map m(std::less<int>{});
- // expected-error-re@-1{{{{no viable constructor or deduction guide for deduction of template arguments of '.*flat_map'}}}}
- }
- {
- // cannot deduce Key and T from just (Compare, Allocator)
- std::flat_map m(std::less<int>{}, std::allocator<PC>{});
- // expected-error-re@-1{{{{no viable constructor or deduction guide for deduction of template arguments of '.*flat_map'}}}}
- }
- {
- // cannot deduce Key and T from just (Allocator)
- std::flat_map m(std::allocator<PC>{});
- // expected-error-re@-1{{{{no viable constructor or deduction guide for deduction of template arguments of '.*flat_map'}}}}
- }
- {
- // cannot convert from some arbitrary unrelated type
- NotAnAllocator a;
- std::flat_map m(a);
- // expected-error-re@-1{{{{no viable constructor or deduction guide for deduction of template arguments of '.*flat_map'}}}}
- }
{
// cannot deduce that the inner braced things should be std::pair and not something else
std::flat_map m{{1, 1L}, {2, 2L}, {3, 3L}};
diff --git a/libcxx/test/std/containers/container.adaptors/flat.map/flat.map.cons/default_noexcept.pass.cpp b/libcxx/test/std/containers/container.adaptors/flat.map/flat.map.cons/default_noexcept.pass.cpp
index ac24c8a8ac067..790dfa4a02ed5 100644
--- a/libcxx/test/std/containers/container.adaptors/flat.map/flat.map.cons/default_noexcept.pass.cpp
+++ b/libcxx/test/std/containers/container.adaptors/flat.map/flat.map.cons/default_noexcept.pass.cpp
@@ -37,10 +37,12 @@ int main(int, char**) {
{
using C = std::flat_map<MoveOnly, MoveOnly>;
static_assert(std::is_nothrow_default_constructible_v<C>);
+ C c;
}
{
using C = std::flat_map<MoveOnly, MoveOnly, std::less<MoveOnly>, std::vector<MoveOnly, test_allocator<MoveOnly>>>;
static_assert(std::is_nothrow_default_constructible_v<C>);
+ C c;
}
#endif // _LIBCPP_VERSION
{
diff --git a/libcxx/test/std/containers/container.adaptors/flat.map/flat.map.cons/dtor_noexcept.pass.cpp b/libcxx/test/std/containers/container.adaptors/flat.map/flat.map.cons/dtor_noexcept.pass.cpp
index e3ab33a55d95b..1570b0fa14888 100644
--- a/libcxx/test/std/containers/container.adaptors/flat.map/flat.map.cons/dtor_noexcept.pass.cpp
+++ b/libcxx/test/std/containers/container.adaptors/flat.map/flat.map.cons/dtor_noexcept.pass.cpp
@@ -24,28 +24,32 @@
struct ThrowingDtorComp {
bool operator()(const auto&, const auto&) const;
- ~ThrowingDtorComp() noexcept(false);
+ ~ThrowingDtorComp() noexcept(false) {}
};
int main(int, char**) {
{
using C = std::flat_map<MoveOnly, MoveOnly>;
static_assert(std::is_nothrow_destructible_v<C>);
+ C c;
}
{
using V = std::vector<MoveOnly, test_allocator<MoveOnly>>;
using C = std::flat_map<MoveOnly, MoveOnly, std::less<MoveOnly>, V, V>;
static_assert(std::is_nothrow_destructible_v<C>);
+ C c;
}
{
using V = std::deque<MoveOnly, other_allocator<MoveOnly>>;
using C = std::flat_map<MoveOnly, MoveOnly, std::greater<MoveOnly>, V, V>;
static_assert(std::is_nothrow_destructible_v<C>);
+ C c;
}
#if defined(_LIBCPP_VERSION)
{
using C = std::flat_map<MoveOnly, MoveOnly, ThrowingDtorComp>;
static_assert(!std::is_nothrow_destructible_v<C>);
+ C c;
}
#endif // _LIBCPP_VERSION
diff --git a/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.capacity/empty.pass.cpp b/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.capacity/empty.pass.cpp
new file mode 100644
index 0000000000000..4fa4fd6a69b94
--- /dev/null
+++ b/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.capacity/empty.pass.cpp
@@ -0,0 +1,51 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+// UNSUPPORTED: c++03, c++11, c++14, c++17, c++20
+
+// <flat_map>
+
+// class flat_multimap
+
+// [[nodiscard]] bool empty() const noexcept;
+
+#include <flat_map>
+#include <cassert>
+#include <deque>
+#include <functional>
+#include <utility>
+#include <vector>
+
+#include "MinSequenceContainer.h"
+#include "test_macros.h"
+#include "min_allocator.h"
+
+template <class KeyContainer, class ValueContainer>
+void test() {
+ using Key = typename KeyContainer::value_type;
+ using Value = typename ValueContainer::value_type;
+ using M = std::flat_multimap<Key, Value, std::less<int>, KeyContainer, ValueContainer>;
+ M m;
+ ASSERT_SAME_TYPE(decltype(m.empty()), bool);
+ ASSERT_NOEXCEPT(m.empty());
+ assert(m.empty());
+ assert(std::as_const(m).empty());
+ m = {{1, 1.0}, {1, 2.0}};
+ assert(!m.empty());
+ m.clear();
+ assert(m.empty());
+}
+
+int main(int, char**) {
+ test<std::vector<int>, std::vector<double>>();
+ test<std::deque<int>, std::vector<double>>();
+ test<MinSequenceContainer<int>, MinSequenceContainer<double>>();
+ test<std::vector<int, min_allocator<int>>, std::vector<double, min_allocator<double>>>();
+
+ return 0;
+}
diff --git a/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.capacity/empty.verify.cpp b/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.capacity/empty.verify.cpp
new file mode 100644
index 0000000000000..9b7b827c9bec8
--- /dev/null
+++ b/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.capacity/empty.verify.cpp
@@ -0,0 +1,22 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+// UNSUPPORTED: c++03, c++11, c++14, c++17, c++20
+
+// <flat_map>
+
+// class flat_multimap
+
+// [[nodiscard]] bool empty() const noexcept;
+
+#include <flat_map>
+
+void f() {
+ std::flat_multimap<int, int> c;
+ c.empty(); // expected-warning {{ignoring return value of function declared with 'nodiscard' attribute}}
+}
diff --git a/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.capacity/max_size.pass.cpp b/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.capacity/max_size.pass.cpp
new file mode 100644
index 0000000000000..0960c43c5a90a
--- /dev/null
+++ b/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.capacity/max_size.pass.cpp
@@ -0,0 +1,78 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+// UNSUPPORTED: c++03, c++11, c++14, c++17, c++20
+
+// <flat_map>
+
+// class flat_multimap
+
+// size_type max_size() const noexcept;
+
+#include <cassert>
+#include <deque>
+#include <flat_map>
+#include <functional>
+#include <limits>
+#include <type_traits>
+#include <vector>
+
+#include "MinSequenceContainer.h"
+#include "test_allocator.h"
+#include "test_macros.h"
+
+int main(int, char**) {
+ {
+ using A1 = limited_allocator<int, 10>;
+ using A2 = limited_allocator<int, 20>;
+ using C = std::flat_multimap<int, int, std::less<int>, std::vector<int, A1>, std::vector<int, A2>>;
+ ASSERT_SAME_TYPE(C::difference_type, std::ptrdiff_t);
+ ASSERT_SAME_TYPE(C::size_type, std::size_t);
+ const C c;
+ ASSERT_NOEXCEPT(c.max_size());
+ ASSERT_SAME_TYPE(decltype(c.max_size()), C::size_type);
+ assert(c.max_size() <= 10);
+ LIBCPP_ASSERT(c.max_size() == 10);
+ }
+ {
+ using A1 = limited_allocator<int, 10>;
+ using A2 = limited_allocator<int, 20>;
+ using C = std::flat_multimap<int, int, std::less<int>, std::vector<int, A2>, std::vector<int, A1>>;
+ ASSERT_SAME_TYPE(C::difference_type, std::ptrdiff_t);
+ ASSERT_SAME_TYPE(C::size_type, std::size_t);
+ const C c;
+ ASSERT_NOEXCEPT(c.max_size());
+ ASSERT_SAME_TYPE(decltype(c.max_size()), C::size_type);
+ assert(c.max_size() <= 10);
+ LIBCPP_ASSERT(c.max_size() == 10);
+ }
+ {
+ using A = limited_allocator<int, (size_t)-1>;
+ using C = std::flat_multimap<int, int, std::less<int>, std::vector<int, A>, std::vector<int, A>>;
+ ASSERT_SAME_TYPE(C::difference_type, std::ptrdiff_t);
+ ASSERT_SAME_TYPE(C::size_type, std::size_t);
+ const C::size_type max_dist = static_cast<C::size_type>(std::numeric_limits<C::difference_type>::max());
+ const C c;
+ ASSERT_NOEXCEPT(c.max_size());
+ ASSERT_SAME_TYPE(decltype(c.max_size()), C::size_type);
+ assert(c.max_size() <= max_dist);
+ LIBCPP_ASSERT(c.max_size() == max_dist);
+ }
+ {
+ typedef std::flat_multimap<char, char> C;
+ ASSERT_SAME_TYPE(C::difference_type, std::ptrdiff_t);
+ ASSERT_SAME_TYPE(C::size_type, std::size_t);
+ const C::size_type max_dist = static_cast<C::size_type>(std::numeric_limits<C::difference_type>::max());
+ const C c;
+ ASSERT_NOEXCEPT(c.max_size());
+ ASSERT_SAME_TYPE(decltype(c.max_size()), C::size_type);
+ assert(c.max_size() <= max_dist);
+ assert(c.max_size() <= alloc_max_size(std::allocator<char>()));
+ }
+ return 0;
+}
diff --git a/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.capacity/size.pass.cpp b/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.capacity/size.pass.cpp
new file mode 100644
index 0000000000000..533f8da631fc8
--- /dev/null
+++ b/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.capacity/size.pass.cpp
@@ -0,0 +1,70 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+// UNSUPPORTED: c++03, c++11, c++14, c++17, c++20
+
+// <flat_map>
+
+// class flat_multimap
+
+// size_type size() const noexcept;
+
+#include <cassert>
+#include <deque>
+#include <flat_map>
+#include <functional>
+#include <vector>
+
+#include "MinSequenceContainer.h"
+#include "test_macros.h"
+#include "min_allocator.h"
+
+template <class KeyContainer, class ValueContainer>
+void test() {
+ using M = std::flat_multimap<int, char, std::less<int>, KeyContainer, ValueContainer>;
+ {
+ const M m = {{1, 'a'}, {1, 'b'}, {4, 'd'}, {5, 'e'}, {5, 'h'}};
+ ASSERT_SAME_TYPE(decltype(m.size()), std::size_t);
+ ASSERT_NOEXCEPT(m.size());
+ assert(m.size() == 5);
+ }
+ {
+ const M m = {{1, 'a'}};
+ ASSERT_SAME_TYPE(decltype(m.size()), std::size_t);
+ ASSERT_NOEXCEPT(m.size());
+ assert(m.size() == 1);
+ }
+ {
+ const M m;
+ ASSERT_SAME_TYPE(decltype(m.size()), std::size_t);
+ ASSERT_NOEXCEPT(m.size());
+ assert(m.size() == 0);
+ }
+ {
+ M m;
+ std::size_t s = 1000;
+ for (auto i = 0u; i < s; ++i) {
+ m.emplace(i, 'a');
+ }
+ for (auto i = 0u; i < s; ++i) {
+ m.emplace(i, 'b');
+ }
+ ASSERT_SAME_TYPE(decltype(m.size()), std::size_t);
+ ASSERT_NOEXCEPT(m.size());
+ assert(m.size() == 2 * s);
+ }
+}
+
+int main(int, char**) {
+ test<std::vector<int>, std::vector<char>>();
+ test<std::deque<int>, std::vector<char>>();
+ test<MinSequenceContainer<int>, MinSequenceContainer<char>>();
+ test<std::vector<int, min_allocator<int>>, std::vector<char, min_allocator<char>>>();
+
+ return 0;
+}
diff --git a/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.cons/alloc.pass.cpp b/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.cons/alloc.pass.cpp
new file mode 100644
index 0000000000000..3e155eb2a1075
--- /dev/null
+++ b/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.cons/alloc.pass.cpp
@@ -0,0 +1,72 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+// UNSUPPORTED: c++03, c++11, c++14, c++17, c++20
+
+// <flat_map>
+
+// template<class Allocator>
+// explicit flat_multimap(const Allocator& a);
+
+#include <cassert>
+#include <flat_map>
+#include <functional>
+#include <vector>
+
+#include "test_macros.h"
+#include "test_allocator.h"
+#include "../../../test_compare.h"
+
+int main(int, char**) {
+ {
+ // The constructors in this subclause shall not participate in overload
+ // resolution unless uses_allocator_v<key_container_type, Alloc> is true
+ // and uses_allocator_v<mapped_container_type, Alloc> is true.
+
+ using C = test_less<int>;
+ using A1 = test_allocator<int>;
+ using A2 = other_allocator<int>;
+ using V1 = std::vector<int, A1>;
+ using V2 = std::vector<int, A2>;
+ using M1 = std::flat_multimap<int, int, C, V1, V1>;
+ using M2 = std::flat_multimap<int, int, C, V1, V2>;
+ using M3 = std::flat_multimap<int, int, C, V2, V1>;
+ static_assert(std::is_constructible_v<M1, const A1&>);
+ static_assert(!std::is_constructible_v<M1, const A2&>);
+ static_assert(!std::is_constructible_v<M2, const A2&>);
+ static_assert(!std::is_constructible_v<M3, const A2&>);
+ }
+ {
+ // explicit
+ using M =
+ std::flat_multimap<int,
+ long,
+ std::less<int>,
+ std::vector<int, test_allocator<int>>,
+ std::vector<long, test_allocator<long>>>;
+
+ static_assert(std::is_constructible_v<M, test_allocator<int>>);
+ static_assert(!std::is_convertible_v<test_allocator<int>, M>);
+ }
+ {
+ using A = test_allocator<short>;
+ using M =
+ std::flat_multimap<int,
+ long,
+ std::less<int>,
+ std::vector<int, test_allocator<int>>,
+ std::vector<long, test_allocator<long>>>;
+ M m(A(0, 5));
+ assert(m.empty());
+ assert(m.begin() == m.end());
+ assert(m.keys().get_allocator().get_id() == 5);
+ assert(m.values().get_allocator().get_id() == 5);
+ }
+
+ return 0;
+}
diff --git a/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.cons/assign_initializer_list.pass.cpp b/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.cons/assign_initializer_list.pass.cpp
new file mode 100644
index 0000000000000..32f75daae7e38
--- /dev/null
+++ b/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.cons/assign_initializer_list.pass.cpp
@@ -0,0 +1,58 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+// UNSUPPORTED: c++03, c++11, c++14, c++17, c++20
+
+// <flat_map>
+
+// flat_multimap& operator=(initializer_list<value_type> il);
+
+#include <algorithm>
+#include <cassert>
+#include <deque>
+#include <flat_map>
+#include <functional>
+#include <ranges>
+#include <vector>
+
+#include "MinSequenceContainer.h"
+#include "test_macros.h"
+#include "min_allocator.h"
+#include "test_allocator.h"
+
+template <class KeyContainer, class ValueContainer>
+void test() {
+ using Key = typename KeyContainer::value_type;
+ using Value = typename ValueContainer::value_type;
+ using M = std::flat_multimap<Key, Value, std::less<Key>, KeyContainer, ValueContainer>;
+ {
+ M m = {{8, 8}, {10, 10}};
+ assert(m.size() == 2);
+ m = {{3, 0}, {1, 0}, {2, 0}, {2, 1}, {3, 1}, {4, 0}, {3, 2}, {5, 0}, {6, 0}, {5, 1}};
+ std::pair<int, int> expected[] = {{1, 0}, {2, 0}, {2, 1}, {3, 0}, {3, 1}, {3, 2}, {4, 0}, {5, 0}, {5, 1}, {6, 0}};
+ assert(std::ranges::equal(m, expected));
+ }
+ {
+ M m = {{10, 1}, {8, 1}};
+ assert(m.size() == 2);
+ m = {{3, 2}};
+ std::pair<double, double> expected[] = {{3, 2}};
+ assert(std::ranges::equal(m, expected));
+ }
+}
+
+int main(int, char**) {
+ test<std::vector<int>, std::vector<int>>();
+ test<std::vector<int>, std::vector<double>>();
+ test<std::deque<int>, std::vector<double>>();
+ test<MinSequenceContainer<int>, MinSequenceContainer<double>>();
+ test<std::vector<int, min_allocator<int>>, std::vector<double, min_allocator<double>>>();
+ test<std::vector<int, min_allocator<int>>, std::vector<int, min_allocator<int>>>();
+
+ return 0;
+}
diff --git a/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.cons/compare.pass.cpp b/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.cons/compare.pass.cpp
new file mode 100644
index 0000000000000..1989b8a4ff68a
--- /dev/null
+++ b/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.cons/compare.pass.cpp
@@ -0,0 +1,93 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+// UNSUPPORTED: c++03, c++11, c++14, c++17, c++20
+
+// <flat_map>
+
+// explicit flat_multimap(const key_compare& comp);
+// template <class Alloc>
+// flat_multimap(const key_compare& comp, const Alloc& a);
+
+#include <deque>
+#include <flat_map>
+#include <functional>
+#include <type_traits>
+#include <vector>
+
+#include "test_macros.h"
+#include "../../../test_compare.h"
+#include "test_allocator.h"
+
+int main(int, char**) {
+ {
+ // The constructors in this subclause shall not participate in overload
+ // resolution unless uses_allocator_v<key_container_type, Alloc> is true
+ // and uses_allocator_v<mapped_container_type, Alloc> is true.
+
+ using C = test_less<int>;
+ using A1 = test_allocator<int>;
+ using A2 = other_allocator<int>;
+ using M1 = std::flat_multimap<int, int, C, std::vector<int, A1>, std::vector<int, A1>>;
+ using M2 = std::flat_multimap<int, int, C, std::vector<int, A1>, std::vector<int, A2>>;
+ using M3 = std::flat_multimap<int, int, C, std::vector<int, A2>, std::vector<int, A1>>;
+ static_assert(std::is_constructible_v<M1, const C&, const A1&>);
+ static_assert(!std::is_constructible_v<M1, const C&, const A2&>);
+ static_assert(!std::is_constructible_v<M2, const C&, const A2&>);
+ static_assert(!std::is_constructible_v<M3, const C&, const A2&>);
+ }
+ {
+ using C = test_less<int>;
+ auto m = std::flat_multimap<int, char*, C>(C(3));
+ assert(m.empty());
+ assert(m.begin() == m.end());
+ assert(m.key_comp() == C(3));
+ }
+ {
+ // The one-argument ctor is explicit.
+ using C = test_less<int>;
+ static_assert(std::is_constructible_v<std::flat_multimap<int, char*, C>, C>);
+ static_assert(!std::is_convertible_v<C, std::flat_multimap<int, char*, C>>);
+
+ static_assert(std::is_constructible_v<std::flat_multimap<int, char*>, std::less<int>>);
+ static_assert(!std::is_convertible_v<std::less<int>, std::flat_multimap<int, char*>>);
+ }
+ {
+ using C = test_less<int>;
+ using A1 = test_allocator<int>;
+ using A2 = test_allocator<short>;
+ auto m = std::flat_multimap<int, short, C, std::vector<int, A1>, std::vector<short, A2>>(C(4), A1(5));
+ assert(m.empty());
+ assert(m.begin() == m.end());
+ assert(m.key_comp() == C(4));
+ assert(m.keys().get_allocator() == A1(5));
+ assert(m.values().get_allocator() == A2(5));
+ }
+ {
+ // explicit(false)
+ using C = test_less<int>;
+ using A1 = test_allocator<int>;
+ using A2 = test_allocator<short>;
+ std::flat_multimap<int, short, C, std::deque<int, A1>, std::deque<short, A2>> m = {C(4), A1(5)};
+ assert(m.empty());
+ assert(m.begin() == m.end());
+ assert(m.key_comp() == C(4));
+ assert(m.keys().get_allocator() == A1(5));
+ assert(m.values().get_allocator() == A2(5));
+ }
+ {
+ // If an allocator is given, it must be usable by both containers.
+ using A = test_allocator<int>;
+ using M = std::flat_multimap<int, int, std::less<>, std::vector<int>, std::vector<int, A>>;
+ static_assert(std::is_constructible_v<M, std::less<>>);
+ static_assert(!std::is_constructible_v<M, std::less<>, std::allocator<int>>);
+ static_assert(!std::is_constructible_v<M, std::less<>, A>);
+ }
+
+ return 0;
+}
diff --git a/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.cons/containers.pass.cpp b/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.cons/containers.pass.cpp
new file mode 100644
index 0000000000000..17ee3c3864b1b
--- /dev/null
+++ b/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.cons/containers.pass.cpp
@@ -0,0 +1,187 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+// UNSUPPORTED: c++03, c++11, c++14, c++17, c++20
+
+// <flat_map>
+
+// flat_multimap(key_container_type key_cont, mapped_container_type mapped_cont,
+// const key_compare& comp = key_compare());
+// template<class Allocator>
+// flat_multimap(const key_container_type& key_cont, const mapped_container_type& mapped_cont,
+// const Allocator& a);
+// template<class Alloc>
+// flat_multimap(const key_container_type& key_cont, const mapped_container_type& mapped_cont,
+// const key_compare& comp, const Alloc& a);
+
+#include <algorithm>
+#include <deque>
+#include <flat_map>
+#include <functional>
+#include <vector>
+
+#include "min_allocator.h"
+#include "MoveOnly.h"
+#include "test_allocator.h"
+#include "test_iterators.h"
+#include "test_macros.h"
+#include "../../../test_compare.h"
+
+struct P {
+ int first;
+ int second;
+ template <class T, class U>
+ bool operator==(const std::pair<T, U>& rhs) const {
+ return MoveOnly(first) == rhs.first && MoveOnly(second) == rhs.second;
+ }
+};
+
+int main(int, char**) {
+ {
+ // The constructors in this subclause shall not participate in overload
+ // resolution unless uses_allocator_v<key_container_type, Alloc> is true
+ // and uses_allocator_v<mapped_container_type, Alloc> is true.
+
+ using C = test_less<int>;
+ using A1 = test_allocator<int>;
+ using A2 = other_allocator<int>;
+ using V1 = std::vector<int, A1>;
+ using V2 = std::vector<int, A2>;
+ using M1 = std::flat_multimap<int, int, C, V1, V1>;
+ using M2 = std::flat_multimap<int, int, C, V1, V2>;
+ using M3 = std::flat_multimap<int, int, C, V2, V1>;
+ static_assert(std::is_constructible_v<M1, const V1&, const V1&, const A1&>);
+ static_assert(!std::is_constructible_v<M1, const V1&, const V1&, const A2&>);
+ static_assert(!std::is_constructible_v<M2, const V1&, const V2&, const A2&>);
+ static_assert(!std::is_constructible_v<M3, const V2&, const V1&, const A2&>);
+
+ static_assert(std::is_constructible_v<M1, const V1&, const V1&, const C&, const A1&>);
+ static_assert(!std::is_constructible_v<M1, const V1&, const V1&, const C&, const A2&>);
+ static_assert(!std::is_constructible_v<M2, const V1&, const V2&, const C&, const A2&>);
+ static_assert(!std::is_constructible_v<M3, const V2&, const V1&, const C&, const A2&>);
+ }
+ {
+ // flat_multimap(key_container_type , mapped_container_type)
+ using M = std::flat_multimap<int, char>;
+ std::vector<int> ks = {1, 1, 1, 2, 2, 3, 2, 3, 3};
+ std::vector<char> vs = {1, 2, 3, 4, 5, 6, 7, 8, 9};
+ auto m = M(ks, vs);
+ std::pair<int, char> expected[] = {{1, 1}, {1, 2}, {1, 3}, {2, 4}, {2, 5}, {2, 7}, {3, 6}, {3, 8}, {3, 9}};
+ assert(std::ranges::equal(m, expected));
+
+ // explicit(false)
+ M m2 = {ks, vs};
+ assert(m2 == m);
+
+ m = M(std::move(ks), std::move(vs));
+ assert(ks.empty()); // it was moved-from
+ assert(vs.empty()); // it was moved-from
+ assert(std::ranges::equal(m, expected));
+ }
+ {
+ // flat_multimap(key_container_type , mapped_container_type)
+ // move-only
+ P expected[] = {{3, 3}, {3, 2}, {2, 1}, {1, 4}};
+ using Ks = std::deque<int, min_allocator<int>>;
+ using Vs = std::vector<MoveOnly, min_allocator<MoveOnly>>;
+ using M = std::flat_multimap<int, MoveOnly, std::greater<int>, Ks, Vs>;
+ Ks ks = {1, 3, 3, 2};
+ Vs vs;
+ vs.push_back(4);
+ vs.push_back(3);
+ vs.push_back(2);
+ vs.push_back(1);
+ auto m = M(std::move(ks), std::move(vs));
+ assert(ks.empty()); // it was moved-from
+ assert(vs.empty()); // it was moved-from
+ assert(std::ranges::equal(m, expected, std::equal_to<>()));
+ }
+ {
+ // flat_multimap(key_container_type , mapped_container_type)
+ // container's allocators are used
+ using A = test_allocator<int>;
+ using M = std::flat_multimap<int, int, std::less<int>, std::vector<int, A>, std::deque<int, A>>;
+ auto ks = std::vector<int, A>({1, 1, 1, 2, 2, 3, 2, 3, 3}, A(5));
+ auto vs = std::deque<int, A>({1, 1, 1, 2, 2, 3, 2, 3, 3}, A(6));
+ auto m = M(std::move(ks), std::move(vs));
+ assert(ks.empty()); // it was moved-from
+ assert(vs.empty()); // it was moved-from
+ std::pair<int, int> expected[] = {{1, 1}, {1, 1}, {1, 1}, {2, 2}, {2, 2}, {2, 2}, {3, 3}, {3, 3}, {3, 3}};
+ assert(std::ranges::equal(m, expected));
+ assert(m.keys().get_allocator() == A(5));
+ assert(m.values().get_allocator() == A(6));
+ }
+ {
+ // flat_multimap(key_container_type , mapped_container_type, key_compare)
+ using C = test_less<int>;
+ using M = std::flat_multimap<int, char, C>;
+ std::vector<int> ks = {1, 1, 1, 2, 2, 3, 2, 3, 3};
+ std::vector<char> vs = {1, 2, 3, 4, 5, 6, 7, 8, 9};
+ auto m = M(ks, vs, C(4));
+ std::pair<int, char> expected[] = {{1, 1}, {1, 2}, {1, 3}, {2, 4}, {2, 5}, {2, 7}, {3, 6}, {3, 8}, {3, 9}};
+ assert(std::ranges::equal(m, expected));
+ assert(m.key_comp() == C(4));
+
+ // explicit(false)
+ M m2 = {ks, vs, C(4)};
+ assert(m2 == m);
+ assert(m2.key_comp() == C(4));
+ }
+ {
+ // flat_multimap(key_container_type , mapped_container_type, const Allocator&)
+ using A = test_allocator<int>;
+ using M = std::flat_multimap<int, int, std::less<int>, std::vector<int, A>, std::deque<int, A>>;
+ auto ks = std::vector<int, A>({1, 1, 1, 2, 2, 3, 2, 3, 3}, A(5));
+ auto vs = std::deque<int, A>({1, 1, 1, 2, 2, 3, 2, 3, 3}, A(6));
+ auto m = M(ks, vs, A(4)); // replaces the allocators
+ assert(!ks.empty()); // it was an lvalue above
+ assert(!vs.empty()); // it was an lvalue above
+ std::pair<int, int> expected[] = {{1, 1}, {1, 1}, {1, 1}, {2, 2}, {2, 2}, {2, 2}, {3, 3}, {3, 3}, {3, 3}};
+ assert(std::ranges::equal(m, expected));
+ assert(m.keys().get_allocator() == A(4));
+ assert(m.values().get_allocator() == A(4));
+ }
+ {
+ // flat_multimap(key_container_type , mapped_container_type, const Allocator&)
+ // explicit(false)
+ using A = test_allocator<int>;
+ using M = std::flat_multimap<int, int, std::less<int>, std::vector<int, A>, std::deque<int, A>>;
+ auto ks = std::vector<int, A>({1, 1, 1, 2, 2, 3, 2, 3, 3}, A(5));
+ auto vs = std::deque<int, A>({1, 1, 1, 2, 2, 3, 2, 3, 3}, A(6));
+ M m = {ks, vs, A(4)}; // implicit ctor
+ assert(!ks.empty()); // it was an lvalue above
+ assert(!vs.empty()); // it was an lvalue above
+ std::pair<int, int> expected[] = {{1, 1}, {1, 1}, {1, 1}, {2, 2}, {2, 2}, {2, 2}, {3, 3}, {3, 3}, {3, 3}};
+ assert(std::ranges::equal(m, expected));
+ assert(m.keys().get_allocator() == A(4));
+ assert(m.values().get_allocator() == A(4));
+ }
+ {
+ // flat_multimap(key_container_type , mapped_container_type, key_compare, const Allocator&)
+ using C = test_less<int>;
+ using A = test_allocator<int>;
+ using M = std::flat_multimap<int, int, C, std::vector<int, A>, std::vector<int, A>>;
+ std::vector<int, A> ks = {1, 1, 1, 2, 2, 3, 2, 3, 3};
+ std::vector<int, A> vs = {1, 2, 3, 4, 5, 6, 7, 8, 9};
+ auto m = M(ks, vs, C(4), A(5));
+ std::pair<int, char> expected[] = {{1, 1}, {1, 2}, {1, 3}, {2, 4}, {2, 5}, {2, 7}, {3, 6}, {3, 8}, {3, 9}};
+ assert(std::ranges::equal(m, expected));
+ assert(m.key_comp() == C(4));
+ assert(m.keys().get_allocator() == A(5));
+ assert(m.values().get_allocator() == A(5));
+
+ // explicit(false)
+ M m2 = {ks, vs, C(4), A(5)};
+ assert(m2 == m);
+ assert(m2.key_comp() == C(4));
+ assert(m2.keys().get_allocator() == A(5));
+ assert(m2.values().get_allocator() == A(5));
+ }
+
+ return 0;
+}
diff --git a/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.cons/copy.pass.cpp b/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.cons/copy.pass.cpp
new file mode 100644
index 0000000000000..0e6d12cd3c569
--- /dev/null
+++ b/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.cons/copy.pass.cpp
@@ -0,0 +1,70 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+// UNSUPPORTED: c++03, c++11, c++14, c++17, c++20
+
+// <flat_map>
+
+// flat_multimap(const flat_multimap& m);
+
+#include <cassert>
+#include <flat_map>
+#include <vector>
+
+#include "test_macros.h"
+#include "../../../test_compare.h"
+#include "test_allocator.h"
+
+int main(int, char**) {
+ {
+ using C = test_less<int>;
+ std::vector<int, test_allocator<int>> ks({1, 1, 3, 3, 5}, test_allocator<int>(6));
+ std::vector<char, test_allocator<char>> vs({2, 2, 1, 1, 1}, test_allocator<char>(7));
+ using M = std::flat_multimap<int, char, C, decltype(ks), decltype(vs)>;
+ auto mo = M(ks, vs, C(5));
+ auto m = mo;
+
+ assert(m.key_comp() == C(5));
+ assert(m.keys() == ks);
+ assert(m.values() == vs);
+ assert(m.keys().get_allocator() == test_allocator<int>(6));
+ assert(m.values().get_allocator() == test_allocator<char>(7));
+
+ // mo is unchanged
+ assert(mo.key_comp() == C(5));
+ assert(mo.keys() == ks);
+ assert(mo.values() == vs);
+ assert(mo.keys().get_allocator() == test_allocator<int>(6));
+ assert(mo.values().get_allocator() == test_allocator<char>(7));
+ }
+ {
+ using C = test_less<int>;
+ using Ks = std::vector<int, other_allocator<int>>;
+ using Vs = std::vector<char, other_allocator<char>>;
+ auto ks = Ks({1, 3, 5, 5, 5, 5}, other_allocator<int>(6));
+ auto vs = Vs({2, 2, 5, 5, 5, 1}, other_allocator<char>(7));
+ using M = std::flat_multimap<int, char, C, Ks, Vs>;
+ auto mo = M(Ks(ks, other_allocator<int>(6)), Vs(vs, other_allocator<int>(7)), C(5));
+ auto m = mo;
+
+ assert(m.key_comp() == C(5));
+ assert(m.keys() == ks);
+ assert(m.values() == vs);
+ assert(m.keys().get_allocator() == other_allocator<int>(-2));
+ assert(m.values().get_allocator() == other_allocator<char>(-2));
+
+ // mo is unchanged
+ assert(mo.key_comp() == C(5));
+ assert(mo.keys() == ks);
+ assert(mo.values() == vs);
+ assert(mo.keys().get_allocator() == other_allocator<int>(6));
+ assert(mo.values().get_allocator() == other_allocator<char>(7));
+ }
+
+ return 0;
+}
diff --git a/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.cons/copy_alloc.pass.cpp b/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.cons/copy_alloc.pass.cpp
new file mode 100644
index 0000000000000..3047c004d42e9
--- /dev/null
+++ b/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.cons/copy_alloc.pass.cpp
@@ -0,0 +1,67 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+// UNSUPPORTED: c++03, c++11, c++14, c++17, c++20
+
+// <flat_map>
+
+// flat_multimap(const flat_multimap&, const allocator_type&);
+
+#include <cassert>
+#include <deque>
+#include <flat_map>
+#include <functional>
+#include <vector>
+
+#include "test_macros.h"
+#include "../../../test_compare.h"
+#include "test_allocator.h"
+
+int main(int, char**) {
+ {
+ // The constructors in this subclause shall not participate in overload
+ // resolution unless uses_allocator_v<key_container_type, Alloc> is true
+ // and uses_allocator_v<mapped_container_type, Alloc> is true.
+
+ using C = test_less<int>;
+ using A1 = test_allocator<int>;
+ using A2 = other_allocator<int>;
+ using V1 = std::vector<int, A1>;
+ using V2 = std::vector<int, A2>;
+ using M1 = std::flat_multimap<int, int, C, V1, V1>;
+ using M2 = std::flat_multimap<int, int, C, V1, V2>;
+ using M3 = std::flat_multimap<int, int, C, V2, V1>;
+ static_assert(std::is_constructible_v<M1, const M1&, const A1&>);
+ static_assert(!std::is_constructible_v<M1, const M1&, const A2&>);
+ static_assert(!std::is_constructible_v<M2, const M2&, const A2&>);
+ static_assert(!std::is_constructible_v<M3, const M3&, const A2&>);
+ }
+ {
+ using C = test_less<int>;
+ std::vector<int, test_allocator<int>> ks({1, 3, 3, 5, 5}, test_allocator<int>(6));
+ std::vector<char, test_allocator<char>> vs({2, 2, 1, 1, 1}, test_allocator<char>(7));
+ using M = std::flat_multimap<int, char, C, decltype(ks), decltype(vs)>;
+ auto mo = M(ks, vs, C(5));
+ auto m = M(mo, test_allocator<int>(3));
+
+ assert(m.key_comp() == C(5));
+ assert(m.keys() == ks);
+ assert(m.values() == vs);
+ assert(m.keys().get_allocator() == test_allocator<int>(3));
+ assert(m.values().get_allocator() == test_allocator<char>(3));
+
+ // mo is unchanged
+ assert(mo.key_comp() == C(5));
+ assert(mo.keys() == ks);
+ assert(mo.values() == vs);
+ assert(mo.keys().get_allocator() == test_allocator<int>(6));
+ assert(mo.values().get_allocator() == test_allocator<char>(7));
+ }
+
+ return 0;
+}
diff --git a/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.cons/copy_assign.addressof.compile.pass.cpp b/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.cons/copy_assign.addressof.compile.pass.cpp
new file mode 100644
index 0000000000000..233a9c6859318
--- /dev/null
+++ b/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.cons/copy_assign.addressof.compile.pass.cpp
@@ -0,0 +1,30 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+// UNSUPPORTED: c++03, c++11, c++14, c++17, c++20
+
+// <flat_map>
+
+// flat_multimap& operator=(const flat_multimap& s);
+
+// Validate whether the container can be copy-assigned (move-assigned, swapped)
+// with an ADL-hijacking operator&
+
+#include <flat_map>
+#include <utility>
+
+#include "test_macros.h"
+#include "operator_hijacker.h"
+
+void test() {
+ std::flat_multimap<operator_hijacker, operator_hijacker> so;
+ std::flat_multimap<operator_hijacker, operator_hijacker> s;
+ s = so;
+ s = std::move(so);
+ swap(s, so);
+}
diff --git a/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.cons/copy_assign.pass.cpp b/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.cons/copy_assign.pass.cpp
new file mode 100644
index 0000000000000..3dd7ebdd38871
--- /dev/null
+++ b/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.cons/copy_assign.pass.cpp
@@ -0,0 +1,81 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+// UNSUPPORTED: c++03, c++11, c++14, c++17, c++20
+
+// <flat_map>
+
+// flat_multimap& operator=(const flat_multimap& m);
+
+#include <deque>
+#include <flat_map>
+#include <functional>
+#include <vector>
+
+#include "test_macros.h"
+#include "../../../test_compare.h"
+#include "test_allocator.h"
+
+int main(int, char**) {
+ {
+ // test_allocator is not propagated
+ using C = test_less<int>;
+ std::vector<int, test_allocator<int>> ks({1, 1, 3, 3, 5}, test_allocator<int>(6));
+ std::vector<char, test_allocator<char>> vs({1, 2, 3, 4, 5}, test_allocator<char>(7));
+ using M = std::flat_multimap<int, char, C, decltype(ks), decltype(vs)>;
+ auto mo = M(ks, vs, C(5));
+ auto m = M({{3, 3}, {4, 4}, {5, 5}}, C(3), test_allocator<int>(2));
+ m = mo;
+
+ assert(m.key_comp() == C(5));
+ assert(m.keys() == ks);
+ assert(m.values() == vs);
+ assert(m.keys().get_allocator() == test_allocator<int>(2));
+ assert(m.values().get_allocator() == test_allocator<char>(2));
+
+ // mo is unchanged
+ assert(mo.key_comp() == C(5));
+ assert(mo.keys() == ks);
+ assert(mo.values() == vs);
+ assert(mo.keys().get_allocator() == test_allocator<int>(6));
+ assert(mo.values().get_allocator() == test_allocator<char>(7));
+ }
+ {
+ // other_allocator is propagated
+ using C = test_less<int>;
+ using Ks = std::vector<int, other_allocator<int>>;
+ using Vs = std::vector<char, other_allocator<char>>;
+ auto ks = Ks({1, 1, 3, 3, 5}, other_allocator<int>(6));
+ auto vs = Vs({2, 1, 3, 2, 1}, other_allocator<char>(7));
+ using M = std::flat_multimap<int, char, C, Ks, Vs>;
+ auto mo = M(Ks(ks, other_allocator<int>(6)), Vs(vs, other_allocator<int>(7)), C(5));
+ auto m = M({{3, 3}, {4, 4}, {5, 5}}, C(3), other_allocator<int>(2));
+ m = mo;
+
+ assert(m.key_comp() == C(5));
+ assert(m.keys() == ks);
+ assert(m.values() == vs);
+ assert(m.keys().get_allocator() == other_allocator<int>(6));
+ assert(m.values().get_allocator() == other_allocator<char>(7));
+
+ // mo is unchanged
+ assert(mo.key_comp() == C(5));
+ assert(mo.keys() == ks);
+ assert(mo.values() == vs);
+ assert(mo.keys().get_allocator() == other_allocator<int>(6));
+ assert(mo.values().get_allocator() == other_allocator<char>(7));
+ }
+ {
+ // self-assignment
+ using M = std::flat_multimap<int, int>;
+ M m = {{1, 1}, {3, 4}};
+ m = static_cast<const M&>(m);
+ assert((m == M{{1, 1}, {3, 4}}));
+ }
+ return 0;
+}
diff --git a/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.cons/deduct.compile.pass.cpp b/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.cons/deduct.compile.pass.cpp
new file mode 100644
index 0000000000000..a9d8382bd037c
--- /dev/null
+++ b/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.cons/deduct.compile.pass.cpp
@@ -0,0 +1,52 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+// UNSUPPORTED: c++03, c++11, c++14, c++17, c++20
+
+// <flat_map>
+
+// Test CTAD on cases where deduction should fail.
+
+#include <flat_map>
+#include <functional>
+#include <memory>
+#include <utility>
+#include <vector>
+
+struct NotAnAllocator {
+ friend bool operator<(NotAnAllocator, NotAnAllocator) { return false; }
+};
+
+using P = std::pair<int, long>;
+using PC = std::pair<const int, long>;
+
+template <class... Args>
+concept CanDeductFlatMultimap = requires { std::flat_multimap{std::declval<Args>()...}; };
+
+static_assert(CanDeductFlatMultimap<std::vector<int>, std::vector<int>>);
+
+// cannot deduce Key and T from nothing
+static_assert(!CanDeductFlatMultimap<>);
+
+// cannot deduce Key and T from just (KeyContainer), even if it's a container of pairs
+static_assert(!CanDeductFlatMultimap<std::vector<std::pair<int, int>>>);
+
+// cannot deduce Key and T from just (KeyContainer, Allocator)
+static_assert(!CanDeductFlatMultimap<std::vector<int>, std::allocator<std::pair<const int, int>>>);
+
+// cannot deduce Key and T from just (Compare)
+static_assert(!CanDeductFlatMultimap<std::less<int>>);
+
+// cannot deduce Key and T from just (Compare, Allocator)
+static_assert(!CanDeductFlatMultimap<std::less<int>, std::allocator<PC>>);
+
+// cannot deduce Key and T from just (Allocator)
+static_assert(!CanDeductFlatMultimap<std::allocator<PC>>);
+
+// cannot convert from some arbitrary unrelated type
+static_assert(!CanDeductFlatMultimap<NotAnAllocator>);
diff --git a/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.cons/deduct.pass.cpp b/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.cons/deduct.pass.cpp
new file mode 100644
index 0000000000000..a718d9cfad5b7
--- /dev/null
+++ b/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.cons/deduct.pass.cpp
@@ -0,0 +1,343 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+// UNSUPPORTED: c++03, c++11, c++14, c++17, c++20
+
+// <flat_map>
+
+#include <algorithm>
+#include <cassert>
+#include <climits>
+#include <deque>
+#include <initializer_list>
+#include <list>
+#include <flat_map>
+#include <functional>
+#include <ranges>
+#include <type_traits>
+#include <utility>
+#include <vector>
+
+#include "deduction_guides_sfinae_checks.h"
+#include "test_allocator.h"
+
+using P = std::pair<int, long>;
+using PC = std::pair<const int, long>;
+
+void test_copy() {
+ {
+ std::flat_multimap<long, short> source = {{1, 2}, {1, 3}};
+ std::flat_multimap s(source);
+ ASSERT_SAME_TYPE(decltype(s), decltype(source));
+ assert(s == source);
+ }
+ {
+ std::flat_multimap<long, short, std::greater<long>> source = {{1, 2}, {1, 3}};
+ std::flat_multimap s{source}; // braces instead of parens
+ ASSERT_SAME_TYPE(decltype(s), decltype(source));
+ assert(s == source);
+ }
+ {
+ std::flat_multimap<long, short, std::greater<long>> source = {{1, 2}, {1, 3}};
+ std::flat_multimap s(source, std::allocator<int>());
+ ASSERT_SAME_TYPE(decltype(s), decltype(source));
+ assert(s == source);
+ }
+}
+
+void test_containers() {
+ std::deque<int, test_allocator<int>> ks({1, 2, 1, 2, 2, INT_MAX, 3}, test_allocator<int>(0, 42));
+ std::deque<short, test_allocator<short>> vs({1, 2, 3, 4, 5, 3, 4}, test_allocator<int>(0, 43));
+ std::deque<int, test_allocator<int>> sorted_ks({1, 1, 2, 2, 2, 3, INT_MAX}, test_allocator<int>(0, 42));
+ std::deque<short, test_allocator<short>> sorted_vs({1, 3, 2, 4, 5, 4, 3}, test_allocator<int>(0, 43));
+ const std::pair<int, short> expected[] = {{1, 1}, {1, 3}, {2, 2}, {2, 4}, {2, 5}, {3, 4}, {INT_MAX, 3}};
+ {
+ std::flat_multimap s(ks, vs);
+
+ ASSERT_SAME_TYPE(decltype(s), std::flat_multimap<int, short, std::less<int>, decltype(ks), decltype(vs)>);
+ assert(std::ranges::equal(s, expected));
+ assert(s.keys().get_allocator().get_id() == 42);
+ assert(s.values().get_allocator().get_id() == 43);
+ }
+ {
+ std::flat_multimap s(std::sorted_equivalent, sorted_ks, sorted_vs);
+
+ ASSERT_SAME_TYPE(decltype(s), std::flat_multimap<int, short, std::less<int>, decltype(ks), decltype(vs)>);
+ assert(std::ranges::equal(s, expected));
+ assert(s.keys().get_allocator().get_id() == 42);
+ assert(s.values().get_allocator().get_id() == 43);
+ }
+ {
+ std::flat_multimap s(ks, vs, test_allocator<long>(0, 44));
+
+ ASSERT_SAME_TYPE(decltype(s), std::flat_multimap<int, short, std::less<int>, decltype(ks), decltype(vs)>);
+ assert(std::ranges::equal(s, expected));
+ assert(s.keys().get_allocator().get_id() == 44);
+ assert(s.values().get_allocator().get_id() == 44);
+ }
+ {
+ std::flat_multimap s(std::sorted_equivalent, sorted_ks, sorted_vs, test_allocator<long>(0, 44));
+
+ ASSERT_SAME_TYPE(decltype(s), std::flat_multimap<int, short, std::less<int>, decltype(ks), decltype(vs)>);
+ assert(std::ranges::equal(s, expected));
+ assert(s.keys().get_allocator().get_id() == 44);
+ assert(s.values().get_allocator().get_id() == 44);
+ }
+}
+
+void test_containers_compare() {
+ std::deque<int, test_allocator<int>> ks({1, 2, 1, 2, 2, INT_MAX, 3}, test_allocator<int>(0, 42));
+ std::deque<short, test_allocator<short>> vs({1, 2, 3, 4, 5, 3, 4}, test_allocator<int>(0, 43));
+ std::deque<int, test_allocator<int>> sorted_ks({INT_MAX, 3, 2, 2, 2, 1, 1}, test_allocator<int>(0, 42));
+ std::deque<short, test_allocator<short>> sorted_vs({3, 4, 2, 4, 5, 1, 3}, test_allocator<int>(0, 43));
+ const std::pair<int, short> expected[] = {{INT_MAX, 3}, {3, 4}, {2, 2}, {2, 4}, {2, 5}, {1, 1}, {1, 3}};
+ {
+ std::flat_multimap s(ks, vs, std::greater<int>());
+
+ ASSERT_SAME_TYPE(decltype(s), std::flat_multimap<int, short, std::greater<int>, decltype(ks), decltype(vs)>);
+ assert(std::ranges::equal(s, expected));
+ assert(s.keys().get_allocator().get_id() == 42);
+ assert(s.values().get_allocator().get_id() == 43);
+ }
+ {
+ std::flat_multimap s(std::sorted_equivalent, sorted_ks, sorted_vs, std::greater<int>());
+
+ ASSERT_SAME_TYPE(decltype(s), std::flat_multimap<int, short, std::greater<int>, decltype(ks), decltype(vs)>);
+ assert(std::ranges::equal(s, expected));
+ assert(s.keys().get_allocator().get_id() == 42);
+ assert(s.values().get_allocator().get_id() == 43);
+ }
+ {
+ std::flat_multimap s(ks, vs, std::greater<int>(), test_allocator<long>(0, 44));
+
+ ASSERT_SAME_TYPE(decltype(s), std::flat_multimap<int, short, std::greater<int>, decltype(ks), decltype(vs)>);
+ assert(std::ranges::equal(s, expected));
+ assert(s.keys().get_allocator().get_id() == 44);
+ assert(s.values().get_allocator().get_id() == 44);
+ }
+ {
+ std::flat_multimap s(
+ std::sorted_equivalent, sorted_ks, sorted_vs, std::greater<int>(), test_allocator<long>(0, 44));
+
+ ASSERT_SAME_TYPE(decltype(s), std::flat_multimap<int, short, std::greater<int>, decltype(ks), decltype(vs)>);
+ assert(std::ranges::equal(s, expected));
+ assert(s.keys().get_allocator().get_id() == 44);
+ assert(s.values().get_allocator().get_id() == 44);
+ }
+}
+
+void test_iter_iter() {
+ const P arr[] = {{1, 1L}, {2, 2L}, {1, 1L}, {INT_MAX, 1L}, {3, 1L}};
+ const P sorted_arr[] = {{1, 1L}, {1, 1L}, {2, 2L}, {3, 1L}, {INT_MAX, 1L}};
+ const PC arrc[] = {{1, 1L}, {2, 2L}, {1, 1L}, {INT_MAX, 1L}, {3, 1L}};
+ const PC sorted_arrc[] = {{1, 1L}, {1, 1L}, {2, 2L}, {3, 1L}, {INT_MAX, 1L}};
+ {
+ std::flat_multimap m(std::begin(arr), std::end(arr));
+
+ ASSERT_SAME_TYPE(decltype(m), std::flat_multimap<int, long>);
+ assert(std::ranges::equal(m, sorted_arr));
+ }
+ {
+ std::flat_multimap m(std::begin(arrc), std::end(arrc));
+
+ ASSERT_SAME_TYPE(decltype(m), std::flat_multimap<int, long>);
+ assert(std::ranges::equal(m, sorted_arr));
+ }
+ {
+ std::flat_multimap m(std::sorted_equivalent, std::begin(sorted_arr), std::end(sorted_arr));
+
+ ASSERT_SAME_TYPE(decltype(m), std::flat_multimap<int, long>);
+ assert(std::ranges::equal(m, sorted_arr));
+ }
+ {
+ std::flat_multimap m(std::sorted_equivalent, std::begin(sorted_arrc), std::end(sorted_arrc));
+
+ ASSERT_SAME_TYPE(decltype(m), std::flat_multimap<int, long>);
+ assert(std::ranges::equal(m, sorted_arr));
+ }
+ {
+ std::flat_multimap<int, short> mo;
+ std::flat_multimap m(mo.begin(), mo.end());
+ ASSERT_SAME_TYPE(decltype(m), decltype(mo));
+ }
+ {
+ std::flat_multimap<int, short> mo;
+ std::flat_multimap m(mo.cbegin(), mo.cend());
+ ASSERT_SAME_TYPE(decltype(m), decltype(mo));
+ }
+ {
+ std::pair<int, int> source[3] = {{1, 1}, {1, 1}, {3, 3}};
+ std::flat_multimap s = {source, source + 3}; // flat_multimap(InputIterator, InputIterator)
+ ASSERT_SAME_TYPE(decltype(s), std::flat_multimap<int, int>);
+ assert(s.size() == 3);
+ }
+ {
+ std::pair<int, int> source[3] = {{1, 1}, {1, 1}, {3, 3}};
+ std::flat_multimap s{source, source + 3}; // flat_multimap(InputIterator, InputIterator)
+ ASSERT_SAME_TYPE(decltype(s), std::flat_multimap<int, int>);
+ assert(s.size() == 3);
+ }
+ {
+ std::pair<int, int> source[3] = {{1, 1}, {1, 2}, {3, 3}};
+ std::flat_multimap s{
+ std::sorted_equivalent, source, source + 3}; // flat_multimap(sorted_equivalent_t, InputIterator, InputIterator)
+ static_assert(std::is_same_v<decltype(s), std::flat_multimap<int, int>>);
+ assert(s.size() == 3);
+ }
+}
+
+void test_iter_iter_compare() {
+ const P arr[] = {{1, 1L}, {2, 2L}, {1, 1L}, {INT_MAX, 1L}, {3, 1L}};
+ const P sorted_arr[] = {{INT_MAX, 1L}, {3, 1L}, {2, 2L}, {1, 1L}, {1, 1L}};
+ const PC arrc[] = {{1, 1L}, {2, 2L}, {1, 1L}, {INT_MAX, 1L}, {3, 1L}};
+ const PC sorted_arrc[] = {{INT_MAX, 1L}, {3, 1L}, {2, 2L}, {1, 1L}, {1, 1L}};
+ using C = std::greater<long long>;
+ {
+ std::flat_multimap m(std::begin(arr), std::end(arr), C());
+
+ ASSERT_SAME_TYPE(decltype(m), std::flat_multimap<int, long, C>);
+ assert(std::ranges::equal(m, sorted_arr));
+ }
+ {
+ std::flat_multimap m(std::begin(arrc), std::end(arrc), C());
+
+ ASSERT_SAME_TYPE(decltype(m), std::flat_multimap<int, long, C>);
+ assert(std::ranges::equal(m, sorted_arr));
+ }
+ {
+ std::flat_multimap m(std::sorted_equivalent, std::begin(sorted_arr), std::end(sorted_arr), C());
+
+ ASSERT_SAME_TYPE(decltype(m), std::flat_multimap<int, long, C>);
+ assert(std::ranges::equal(m, sorted_arr));
+ }
+ {
+ std::flat_multimap m(std::sorted_equivalent, std::begin(sorted_arrc), std::end(sorted_arrc), C());
+
+ ASSERT_SAME_TYPE(decltype(m), std::flat_multimap<int, long, C>);
+ assert(std::ranges::equal(m, sorted_arr));
+ }
+ {
+ std::flat_multimap<int, short> mo;
+ std::flat_multimap m(mo.begin(), mo.end(), C());
+ ASSERT_SAME_TYPE(decltype(m), std::flat_multimap<int, short, C>);
+ }
+ {
+ std::flat_multimap<int, short> mo;
+ std::flat_multimap m(mo.cbegin(), mo.cend(), C());
+ ASSERT_SAME_TYPE(decltype(m), std::flat_multimap<int, short, C>);
+ }
+}
+
+void test_initializer_list() {
+ const P sorted_arr[] = {{1, 1L}, {1, 1L}, {2, 2L}, {3, 1L}, {INT_MAX, 1L}};
+ {
+ std::flat_multimap m{std::pair{1, 1L}, {2, 2L}, {1, 1L}, {INT_MAX, 1L}, {3, 1L}};
+
+ ASSERT_SAME_TYPE(decltype(m), std::flat_multimap<int, long>);
+ assert(std::ranges::equal(m, sorted_arr));
+ }
+ {
+ std::flat_multimap m(std::sorted_equivalent, {std::pair{1, 1L}, {1, 1L}, {2, 2L}, {3, 1L}, {INT_MAX, 1L}});
+
+ ASSERT_SAME_TYPE(decltype(m), std::flat_multimap<int, long>);
+ assert(std::ranges::equal(m, sorted_arr));
+ }
+ {
+ std::flat_multimap s = {std::make_pair(1, 'a')}; // flat_multimap(initializer_list<pair<int, char>>)
+ ASSERT_SAME_TYPE(decltype(s), std::flat_multimap<int, char>);
+ assert(s.size() == 1);
+ }
+ {
+ using M = std::flat_multimap<int, short>;
+ M m;
+ std::flat_multimap s = {std::make_pair(m, m)}; // flat_multimap(initializer_list<pair<M, M>>)
+ ASSERT_SAME_TYPE(decltype(s), std::flat_multimap<M, M>);
+ assert(s.size() == 1);
+ assert(s.find(m)->second == m);
+ }
+}
+
+void test_initializer_list_compare() {
+ const P sorted_arr[] = {{INT_MAX, 1L}, {3, 1L}, {2, 2L}, {1, 1L}, {1, 1L}};
+ using C = std::greater<long long>;
+ {
+ std::flat_multimap m({std::pair{1, 1L}, {2, 2L}, {1, 1L}, {INT_MAX, 1L}, {3, 1L}}, C());
+
+ ASSERT_SAME_TYPE(decltype(m), std::flat_multimap<int, long, C>);
+ assert(std::ranges::equal(m, sorted_arr));
+ }
+ {
+ std::flat_multimap m(std::sorted_equivalent, {std::pair{INT_MAX, 1L}, {3, 1L}, {2, 2L}, {1, 1L}, {1, 1L}}, C());
+
+ ASSERT_SAME_TYPE(decltype(m), std::flat_multimap<int, long, C>);
+ assert(std::ranges::equal(m, sorted_arr));
+ }
+}
+
+void test_from_range() {
+ std::list<std::pair<int, short>> r = {{1, 1}, {2, 2}, {1, 1}, {INT_MAX, 4}, {3, 5}};
+ const std::pair<int, short> expected[] = {{1, 1}, {1, 1}, {2, 2}, {3, 5}, {INT_MAX, 4}};
+ {
+ std::flat_multimap s(std::from_range, r);
+ ASSERT_SAME_TYPE(decltype(s), std::flat_multimap<int, short, std::less<int>>);
+ assert(std::ranges::equal(s, expected));
+ }
+ {
+ std::flat_multimap s(std::from_range, r, test_allocator<long>(0, 42));
+ ASSERT_SAME_TYPE(
+ decltype(s),
+ std::flat_multimap<int,
+ short,
+ std::less<int>,
+ std::vector<int, test_allocator<int>>,
+ std::vector<short, test_allocator<short>>>);
+ assert(std::ranges::equal(s, expected));
+ assert(s.keys().get_allocator().get_id() == 42);
+ assert(s.values().get_allocator().get_id() == 42);
+ }
+}
+
+void test_from_range_compare() {
+ std::list<std::pair<int, short>> r = {{1, 1}, {2, 2}, {1, 1}, {INT_MAX, 4}, {3, 5}};
+ const std::pair<int, short> expected[] = {{INT_MAX, 4}, {3, 5}, {2, 2}, {1, 1}, {1, 1}};
+ {
+ std::flat_multimap s(std::from_range, r, std::greater<int>());
+ ASSERT_SAME_TYPE(decltype(s), std::flat_multimap<int, short, std::greater<int>>);
+ assert(std::ranges::equal(s, expected));
+ }
+ {
+ std::flat_multimap s(std::from_range, r, std::greater<int>(), test_allocator<long>(0, 42));
+ ASSERT_SAME_TYPE(
+ decltype(s),
+ std::flat_multimap<int,
+ short,
+ std::greater<int>,
+ std::vector<int, test_allocator<int>>,
+ std::vector<short, test_allocator<short>>>);
+ assert(std::ranges::equal(s, expected));
+ assert(s.keys().get_allocator().get_id() == 42);
+ assert(s.values().get_allocator().get_id() == 42);
+ }
+}
+
+int main(int, char**) {
+ // Each test function also tests the sorted_equivalent-prefixed and allocator-suffixed overloads.
+ test_copy();
+ test_containers();
+ test_containers_compare();
+ test_iter_iter();
+ test_iter_iter_compare();
+ test_initializer_list();
+ test_initializer_list_compare();
+ test_from_range();
+ test_from_range_compare();
+
+ AssociativeContainerDeductionGuidesSfinaeAway<std::flat_multimap, std::flat_multimap<int, short>>();
+
+ return 0;
+}
diff --git a/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.cons/deduct.verify.cpp b/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.cons/deduct.verify.cpp
new file mode 100644
index 0000000000000..c25218e890f21
--- /dev/null
+++ b/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.cons/deduct.verify.cpp
@@ -0,0 +1,57 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+// UNSUPPORTED: c++03, c++11, c++14, c++17, c++20
+
+// <flat_map>
+
+// Test CTAD on cases where deduction should fail.
+
+#include <flat_map>
+#include <functional>
+#include <utility>
+
+struct NotAnAllocator {
+ friend bool operator<(NotAnAllocator, NotAnAllocator) { return false; }
+};
+
+using P = std::pair<int, long>;
+using PC = std::pair<const int, long>;
+
+void test() {
+ {
+ // cannot deduce that the inner braced things should be std::pair and not something else
+ std::flat_multimap m{{1, 1L}, {2, 2L}, {3, 3L}};
+ // expected-error-re@-1{{{{no viable constructor or deduction guide for deduction of template arguments of '.*flat_multimap'}}}}
+ }
+ {
+ // cannot deduce that the inner braced things should be std::pair and not something else
+ std::flat_multimap m({{1, 1L}, {2, 2L}, {3, 3L}}, std::less<int>());
+ // expected-error-re@-1{{{{no viable constructor or deduction guide for deduction of template arguments of '.*flat_multimap'}}}}
+ }
+ {
+ // cannot deduce that the inner braced things should be std::pair and not something else
+ std::flat_multimap m({{1, 1L}, {2, 2L}, {3, 3L}}, std::less<int>(), std::allocator<PC>());
+ // expected-error-re@-1{{{{no viable constructor or deduction guide for deduction of template arguments of '.*flat_multimap'}}}}
+ }
+ {
+ // cannot deduce that the inner braced things should be std::pair and not something else
+ std::flat_multimap m({{1, 1L}, {2, 2L}, {3, 3L}}, std::allocator<PC>());
+ // expected-error-re@-1{{{{no viable constructor or deduction guide for deduction of template arguments of '.*flat_multimap'}}}}
+ }
+ {
+ // since we have parens, not braces, this deliberately does not find the initializer_list constructor
+ std::flat_multimap m(P{1, 1L});
+ // expected-error-re@-1{{{{no viable constructor or deduction guide for deduction of template arguments of '.*flat_multimap'}}}}
+ }
+ {
+ // since we have parens, not braces, this deliberately does not find the initializer_list constructor
+ std::flat_multimap m(PC{1, 1L});
+ // expected-error-re@-1{{{{no viable constructor or deduction guide for deduction of template arguments of '.*flat_multimap'}}}}
+ }
+}
diff --git a/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.cons/deduct_pmr.pass.cpp b/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.cons/deduct_pmr.pass.cpp
new file mode 100644
index 0000000000000..1955a8806631b
--- /dev/null
+++ b/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.cons/deduct_pmr.pass.cpp
@@ -0,0 +1,107 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+// UNSUPPORTED: c++03, c++11, c++14, c++17, c++20
+// UNSUPPORTED: availability-pmr-missing
+
+// <flat_map>
+
+#include <algorithm>
+#include <cassert>
+#include <climits>
+#include <deque>
+#include <initializer_list>
+#include <list>
+#include <flat_map>
+#include <functional>
+#include <memory_resource>
+#include <ranges>
+#include <type_traits>
+#include <utility>
+#include <vector>
+
+#include "test_allocator.h"
+
+using P = std::pair<int, long>;
+using PC = std::pair<const int, long>;
+
+void test_containers() {
+ std::deque<int, test_allocator<int>> ks({1, 2, 1, 2, 2, INT_MAX, 3}, test_allocator<int>(0, 42));
+ std::deque<short, test_allocator<short>> vs({1, 2, 3, 4, 5, 3, 4}, test_allocator<int>(0, 43));
+ std::deque<int, test_allocator<int>> sorted_ks({1, 1, 2, 2, 2, 3, INT_MAX}, test_allocator<int>(0, 42));
+ std::deque<short, test_allocator<short>> sorted_vs({1, 3, 2, 4, 5, 4, 3}, test_allocator<int>(0, 43));
+ const std::pair<int, short> expected[] = {{1, 1}, {1, 3}, {2, 2}, {2, 4}, {2, 5}, {3, 4}, {INT_MAX, 3}};
+ {
+ std::pmr::monotonic_buffer_resource mr;
+ std::pmr::monotonic_buffer_resource mr2;
+ std::pmr::deque<int> pks(ks.begin(), ks.end(), &mr);
+ std::pmr::deque<short> pvs(vs.begin(), vs.end(), &mr);
+ std::flat_multimap s(std::move(pks), std::move(pvs), &mr2);
+
+ ASSERT_SAME_TYPE(
+ decltype(s), std::flat_multimap<int, short, std::less<int>, std::pmr::deque<int>, std::pmr::deque<short>>);
+ assert(std::ranges::equal(s, expected));
+ assert(s.keys().get_allocator().resource() == &mr2);
+ assert(s.values().get_allocator().resource() == &mr2);
+ }
+ {
+ std::pmr::monotonic_buffer_resource mr;
+ std::pmr::monotonic_buffer_resource mr2;
+ std::pmr::deque<int> pks(sorted_ks.begin(), sorted_ks.end(), &mr);
+ std::pmr::deque<short> pvs(sorted_vs.begin(), sorted_vs.end(), &mr);
+ std::flat_multimap s(std::sorted_equivalent, std::move(pks), std::move(pvs), &mr2);
+
+ ASSERT_SAME_TYPE(
+ decltype(s), std::flat_multimap<int, short, std::less<int>, std::pmr::deque<int>, std::pmr::deque<short>>);
+ assert(std::ranges::equal(s, expected));
+ assert(s.keys().get_allocator().resource() == &mr2);
+ assert(s.values().get_allocator().resource() == &mr2);
+ }
+}
+
+void test_containers_compare() {
+ std::deque<int, test_allocator<int>> ks({1, 2, 1, 2, 2, INT_MAX, 3}, test_allocator<int>(0, 42));
+ std::deque<short, test_allocator<short>> vs({1, 2, 3, 4, 5, 3, 4}, test_allocator<int>(0, 43));
+ std::deque<int, test_allocator<int>> sorted_ks({INT_MAX, 3, 2, 2, 2, 1, 1}, test_allocator<int>(0, 42));
+ std::deque<short, test_allocator<short>> sorted_vs({3, 4, 2, 4, 5, 1, 3}, test_allocator<int>(0, 43));
+ const std::pair<int, short> expected[] = {{INT_MAX, 3}, {3, 4}, {2, 2}, {2, 4}, {2, 5}, {1, 1}, {1, 3}};
+
+ {
+ std::pmr::monotonic_buffer_resource mr;
+ std::pmr::monotonic_buffer_resource mr2;
+ std::pmr::deque<int> pks(ks.begin(), ks.end(), &mr);
+ std::pmr::deque<short> pvs(vs.begin(), vs.end(), &mr);
+ std::flat_multimap s(std::move(pks), std::move(pvs), std::greater<int>(), &mr2);
+
+ ASSERT_SAME_TYPE(
+ decltype(s), std::flat_multimap<int, short, std::greater<int>, std::pmr::deque<int>, std::pmr::deque<short>>);
+ assert(std::ranges::equal(s, expected));
+ assert(s.keys().get_allocator().resource() == &mr2);
+ assert(s.values().get_allocator().resource() == &mr2);
+ }
+ {
+ std::pmr::monotonic_buffer_resource mr;
+ std::pmr::monotonic_buffer_resource mr2;
+ std::pmr::deque<int> pks(sorted_ks.begin(), sorted_ks.end(), &mr);
+ std::pmr::deque<short> pvs(sorted_vs.begin(), sorted_vs.end(), &mr);
+ std::flat_multimap s(std::sorted_equivalent, std::move(pks), std::move(pvs), std::greater<int>(), &mr2);
+
+ ASSERT_SAME_TYPE(
+ decltype(s), std::flat_multimap<int, short, std::greater<int>, std::pmr::deque<int>, std::pmr::deque<short>>);
+ assert(std::ranges::equal(s, expected));
+ assert(s.keys().get_allocator().resource() == &mr2);
+ assert(s.values().get_allocator().resource() == &mr2);
+ }
+}
+
+int main(int, char**) {
+ test_containers();
+ test_containers_compare();
+
+ return 0;
+}
diff --git a/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.cons/default.pass.cpp b/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.cons/default.pass.cpp
new file mode 100644
index 0000000000000..c910f748d95fe
--- /dev/null
+++ b/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.cons/default.pass.cpp
@@ -0,0 +1,72 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+// UNSUPPORTED: c++03, c++11, c++14, c++17, c++20
+
+// <flat_map>
+
+// flat_multimap();
+
+#include <cassert>
+#include <deque>
+#include <flat_map>
+#include <functional>
+#include <type_traits>
+#include <vector>
+
+#include "test_macros.h"
+#include "min_allocator.h"
+#include "test_allocator.h"
+
+struct DefaultCtableComp {
+ explicit DefaultCtableComp() { default_constructed_ = true; }
+ bool operator()(int, int) const { return false; }
+ bool default_constructed_ = false;
+};
+
+int main(int, char**) {
+ {
+ std::flat_multimap<int, char*> m;
+ assert(m.empty());
+ }
+ {
+ // explicit(false)
+ std::flat_multimap<int, char*> m = {};
+ assert(m.empty());
+ }
+ {
+ std::flat_multimap<int, char*, DefaultCtableComp, std::deque<int, min_allocator<int>>> m;
+ assert(m.empty());
+ assert(m.begin() == m.end());
+ assert(m.key_comp().default_constructed_);
+ }
+ {
+ using A1 = explicit_allocator<int>;
+ using A2 = explicit_allocator<char*>;
+ {
+ std::flat_multimap<int, char*, DefaultCtableComp, std::vector<int, A1>, std::vector<char*, A2>> m;
+ assert(m.empty());
+ assert(m.key_comp().default_constructed_);
+ }
+ {
+ A1 a1;
+ std::flat_multimap<int, int, DefaultCtableComp, std::vector<int, A1>, std::vector<int, A1>> m(a1);
+ assert(m.empty());
+ assert(m.key_comp().default_constructed_);
+ }
+ }
+ {
+ // If an allocator is given, it must be usable by both containers.
+ using A = test_allocator<int>;
+ using M = std::flat_multimap<int, int, std::less<>, std::vector<int>, std::vector<int, A>>;
+ static_assert(std::is_constructible_v<M>);
+ static_assert(!std::is_constructible_v<M, std::allocator<int>>);
+ static_assert(!std::is_constructible_v<M, A>);
+ }
+ return 0;
+}
diff --git a/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.cons/default_noexcept.pass.cpp b/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.cons/default_noexcept.pass.cpp
new file mode 100644
index 0000000000000..fa490f120875f
--- /dev/null
+++ b/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.cons/default_noexcept.pass.cpp
@@ -0,0 +1,61 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+// UNSUPPORTED: c++03, c++11, c++14, c++17, c++20
+
+// <flat_map>
+
+// flat_multimap()
+// noexcept(
+// is_nothrow_default_constructible_v<key_container_type> &&
+// is_nothrow_default_constructible_v<mapped_container_type> &&
+// is_nothrow_default_constructible_v<key_compare>);
+
+// This tests a conforming extension
+
+#include <cassert>
+#include <flat_map>
+#include <functional>
+#include <vector>
+
+#include "test_macros.h"
+#include "MoveOnly.h"
+#include "test_allocator.h"
+
+struct ThrowingCtorComp {
+ ThrowingCtorComp() noexcept(false) {}
+ bool operator()(const auto&, const auto&) const { return false; }
+};
+
+int main(int, char**) {
+#if defined(_LIBCPP_VERSION)
+ {
+ using C = std::flat_multimap<MoveOnly, MoveOnly>;
+ static_assert(std::is_nothrow_default_constructible_v<C>);
+ C c;
+ }
+ {
+ using C =
+ std::flat_multimap<MoveOnly, MoveOnly, std::less<MoveOnly>, std::vector<MoveOnly, test_allocator<MoveOnly>>>;
+ static_assert(std::is_nothrow_default_constructible_v<C>);
+ C c;
+ }
+#endif // _LIBCPP_VERSION
+ {
+ using C =
+ std::flat_multimap<MoveOnly, MoveOnly, std::less<MoveOnly>, std::vector<MoveOnly, other_allocator<MoveOnly>>>;
+ static_assert(!std::is_nothrow_default_constructible_v<C>);
+ C c;
+ }
+ {
+ using C = std::flat_multimap<MoveOnly, MoveOnly, ThrowingCtorComp>;
+ static_assert(!std::is_nothrow_default_constructible_v<C>);
+ C c;
+ }
+ return 0;
+}
diff --git a/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.cons/dtor_noexcept.pass.cpp b/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.cons/dtor_noexcept.pass.cpp
new file mode 100644
index 0000000000000..fd31e440a6614
--- /dev/null
+++ b/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.cons/dtor_noexcept.pass.cpp
@@ -0,0 +1,57 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+// UNSUPPORTED: c++03, c++11, c++14, c++17, c++20
+
+// <flat_map>
+
+// ~flat_multimap();
+
+#include <cassert>
+#include <deque>
+#include <flat_map>
+#include <functional>
+#include <vector>
+
+#include "test_macros.h"
+#include "MoveOnly.h"
+#include "test_allocator.h"
+
+struct ThrowingDtorComp {
+ bool operator()(const auto&, const auto&) const;
+ ~ThrowingDtorComp() noexcept(false) {}
+};
+
+int main(int, char**) {
+ {
+ using C = std::flat_multimap<MoveOnly, MoveOnly>;
+ static_assert(std::is_nothrow_destructible_v<C>);
+ C c;
+ }
+ {
+ using V = std::vector<MoveOnly, test_allocator<MoveOnly>>;
+ using C = std::flat_multimap<MoveOnly, MoveOnly, std::less<MoveOnly>, V, V>;
+ static_assert(std::is_nothrow_destructible_v<C>);
+ C c;
+ }
+ {
+ using V = std::deque<MoveOnly, other_allocator<MoveOnly>>;
+ using C = std::flat_multimap<MoveOnly, MoveOnly, std::greater<MoveOnly>, V, V>;
+ static_assert(std::is_nothrow_destructible_v<C>);
+ C c;
+ }
+#if defined(_LIBCPP_VERSION)
+ {
+ using C = std::flat_multimap<MoveOnly, MoveOnly, ThrowingDtorComp>;
+ static_assert(!std::is_nothrow_destructible_v<C>);
+ C c;
+ }
+#endif // _LIBCPP_VERSION
+
+ return 0;
+}
diff --git a/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.cons/initializer_list.pass.cpp b/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.cons/initializer_list.pass.cpp
new file mode 100644
index 0000000000000..8e89192ec0ea1
--- /dev/null
+++ b/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.cons/initializer_list.pass.cpp
@@ -0,0 +1,159 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+// UNSUPPORTED: c++03, c++11, c++14, c++17, c++20
+
+// <flat_map>
+
+// flat_multimap(initializer_list<value_type> il, const key_compare& comp = key_compare());
+// template<class Alloc>
+// flat_multimap(initializer_list<value_type> il, const Alloc& a);
+// template<class Alloc>
+// flat_multimap(initializer_list<value_type> il, const key_compare& comp, const Alloc& a);
+
+#include <algorithm>
+#include <cassert>
+#include <deque>
+#include <flat_map>
+#include <functional>
+#include <type_traits>
+#include <vector>
+
+#include "test_macros.h"
+#include "min_allocator.h"
+#include "test_allocator.h"
+
+#include "../../../test_compare.h"
+
+struct DefaultCtableComp {
+ explicit DefaultCtableComp() { default_constructed_ = true; }
+ bool operator()(int, int) const { return false; }
+ bool default_constructed_ = false;
+};
+
+int main(int, char**) {
+ {
+ // The constructors in this subclause shall not participate in overload
+ // resolution unless uses_allocator_v<key_container_type, Alloc> is true
+ // and uses_allocator_v<mapped_container_type, Alloc> is true.
+
+ using C = test_less<int>;
+ using A1 = test_allocator<int>;
+ using A2 = other_allocator<int>;
+ using V1 = std::vector<int, A1>;
+ using V2 = std::vector<int, A2>;
+ using M1 = std::flat_multimap<int, int, C, V1, V1>;
+ using M2 = std::flat_multimap<int, int, C, V1, V2>;
+ using M3 = std::flat_multimap<int, int, C, V2, V1>;
+ using IL = std::initializer_list<std::pair<int, int>>;
+ static_assert(std::is_constructible_v<M1, IL, const A1&>);
+ static_assert(!std::is_constructible_v<M1, IL, const A2&>);
+ static_assert(!std::is_constructible_v<M2, IL, const A2&>);
+ static_assert(!std::is_constructible_v<M3, IL, const A2&>);
+
+ static_assert(std::is_constructible_v<M1, IL, const C&, const A1&>);
+ static_assert(!std::is_constructible_v<M1, IL, const C&, const A2&>);
+ static_assert(!std::is_constructible_v<M2, IL, const C&, const A2&>);
+ static_assert(!std::is_constructible_v<M3, IL, const C&, const A2&>);
+ }
+
+ {
+ // initializer_list<value_type> needs to match exactly
+ using M = std::flat_multimap<int, short>;
+ using C = typename M::key_compare;
+ static_assert(std::is_constructible_v<M, std::initializer_list<std::pair<int, short>>>);
+ static_assert(std::is_constructible_v<M, std::initializer_list<std::pair<int, short>>, C>);
+ static_assert(std::is_constructible_v<M, std::initializer_list<std::pair<int, short>>, C, std::allocator<int>>);
+ static_assert(std::is_constructible_v<M, std::initializer_list<std::pair<int, short>>, std::allocator<int>>);
+ static_assert(!std::is_constructible_v<M, std::initializer_list<std::pair<const int, short>>>);
+ static_assert(!std::is_constructible_v<M, std::initializer_list<std::pair<const int, short>>, C>);
+ static_assert(
+ !std::is_constructible_v<M, std::initializer_list<std::pair<const int, short>>, C, std::allocator<int>>);
+ static_assert(!std::is_constructible_v<M, std::initializer_list<std::pair<const int, short>>, std::allocator<int>>);
+ static_assert(!std::is_constructible_v<M, std::initializer_list<std::pair<const int, const short>>>);
+ static_assert(!std::is_constructible_v<M, std::initializer_list<std::pair<const int, const short>>, C>);
+ static_assert(
+ !std::is_constructible_v<M, std::initializer_list<std::pair<const int, const short>>, C, std::allocator<int>>);
+ static_assert(
+ !std::is_constructible_v<M, std::initializer_list<std::pair<const int, const short>>, std::allocator<int>>);
+ }
+
+ std::pair<int, short> expected[] = {{1, 1}, {2, 2}, {2, 2}, {3, 3}, {3, 3}, {5, 2}};
+ {
+ // flat_multimap(initializer_list<value_type>);
+ using M = std::flat_multimap<int, short>;
+ std::initializer_list<std::pair<int, short>> il = {{5, 2}, {2, 2}, {2, 2}, {3, 3}, {1, 1}, {3, 3}};
+ M m(il);
+ assert(std::ranges::equal(m, expected));
+ }
+ {
+ // flat_multimap(initializer_list<value_type>);
+ // explicit(false)
+ using M = std::flat_multimap<int, short>;
+ M m = {{5, 2}, {2, 2}, {2, 2}, {3, 3}, {1, 1}, {3, 3}};
+ assert(std::ranges::equal(m, expected));
+ }
+ {
+ // flat_multimap(initializer_list<value_type>);
+ using M = std::flat_multimap<int, short, std::greater<int>, std::deque<int, min_allocator<int>>>;
+ M m = {{5, 2}, {2, 2}, {2, 2}, {3, 3}, {1, 1}, {3, 3}};
+ assert(std::equal(m.rbegin(), m.rend(), expected, expected + 6));
+ }
+ {
+ using A = explicit_allocator<int>;
+ {
+ // flat_multimap(initializer_list<value_type>);
+ // different comparator
+ using M = std::flat_multimap<int, int, DefaultCtableComp, std::vector<int, A>, std::deque<int, A>>;
+ M m = {{1, 1}, {2, 2}, {3, 3}};
+ assert(m.size() == 3);
+
+ std::pair<int, int> expected1[] = {{1, 1}, {2, 2}, {3, 3}};
+ assert(std::ranges::equal(m, expected1));
+ assert(m.key_comp().default_constructed_);
+ }
+ {
+ // flat_multimap(initializer_list<value_type>, const Allocator&);
+ using M = std::flat_multimap<int, int, std::greater<int>, std::deque<int, A>, std::vector<int, A>>;
+ A a;
+ M m({{5, 2}, {2, 2}, {2, 2}, {3, 3}, {1, 1}, {3, 3}}, a);
+ assert(std::equal(m.rbegin(), m.rend(), expected, expected + 6));
+ }
+ }
+ {
+ // flat_multimap(initializer_list<value_type>, const key_compare&);
+ using C = test_less<int>;
+ using M = std::flat_multimap<int, short, C>;
+ auto m = M({{5, 2}, {2, 2}, {2, 2}, {3, 3}, {1, 1}, {3, 3}}, C(10));
+ assert(std::ranges::equal(m, expected));
+ assert(m.key_comp() == C(10));
+
+ // explicit(false)
+ M m2 = {{{5, 2}, {2, 2}, {2, 2}, {3, 3}, {1, 1}, {3, 3}}, C(10)};
+ assert(m2 == m);
+ assert(m2.key_comp() == C(10));
+ }
+ {
+ // flat_multimap(initializer_list<value_type>, const key_compare&);
+ // Sorting uses the comparator that was passed in
+ using M = std::flat_multimap<int, short, std::function<bool(int, int)>, std::deque<int, min_allocator<int>>>;
+ auto m = M({{5, 2}, {2, 2}, {2, 2}, {3, 3}, {1, 1}, {3, 3}}, std::greater<int>());
+ assert(std::equal(m.rbegin(), m.rend(), expected, expected + 6));
+ assert(m.key_comp()(2, 1) == true);
+ }
+ {
+ // flat_multimap(initializer_list<value_type> il, const key_compare& comp, const Alloc& a);
+ using A = explicit_allocator<int>;
+ using M = std::flat_multimap<int, int, std::greater<int>, std::deque<int, A>, std::vector<int, A>>;
+ A a;
+ M m({{5, 2}, {2, 2}, {2, 2}, {3, 3}, {1, 1}, {3, 3}}, {}, a);
+ assert(std::equal(m.rbegin(), m.rend(), expected, expected + 6));
+ }
+
+ return 0;
+}
diff --git a/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.cons/iter_iter.pass.cpp b/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.cons/iter_iter.pass.cpp
new file mode 100644
index 0000000000000..c9c5e6c99d1c8
--- /dev/null
+++ b/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.cons/iter_iter.pass.cpp
@@ -0,0 +1,154 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+// UNSUPPORTED: c++03, c++11, c++14, c++17, c++20
+
+// <flat_map>
+
+// template <class InputIterator>
+// flat_multimap(InputIterator first, InputIterator last, const key_compare& comp = key_compare());
+// template<class InputIterator, class Allocator>
+// flat_multimap(InputIterator first, InputIterator last, const Allocator& a);
+// template<class InputIterator, class Allocator>
+// flat_multimap(InputIterator first, InputIterator last, const key_compare& comp, const Allocator& a);
+
+#include <algorithm>
+#include <deque>
+#include <flat_map>
+#include <functional>
+#include <vector>
+
+#include "min_allocator.h"
+#include "test_allocator.h"
+#include "test_iterators.h"
+#include "test_macros.h"
+#include "../../../test_compare.h"
+
+int main(int, char**) {
+ {
+ // The constructors in this subclause shall not participate in overload
+ // resolution unless uses_allocator_v<key_container_type, Alloc> is true
+ // and uses_allocator_v<mapped_container_type, Alloc> is true.
+
+ using C = test_less<int>;
+ using A1 = test_allocator<int>;
+ using A2 = other_allocator<int>;
+ using V1 = std::vector<int, A1>;
+ using V2 = std::vector<int, A2>;
+ using M1 = std::flat_multimap<int, int, C, V1, V1>;
+ using M2 = std::flat_multimap<int, int, C, V1, V2>;
+ using M3 = std::flat_multimap<int, int, C, V2, V1>;
+ using Iter1 = typename M1::iterator;
+ using Iter2 = typename M2::iterator;
+ using Iter3 = typename M3::iterator;
+ static_assert(std::is_constructible_v<M1, Iter1, Iter1, const A1&>);
+ static_assert(!std::is_constructible_v<M1, Iter1, Iter1, const A2&>);
+ static_assert(!std::is_constructible_v<M2, Iter2, Iter2, const A2&>);
+ static_assert(!std::is_constructible_v<M3, Iter3, Iter3, const A2&>);
+
+ static_assert(std::is_constructible_v<M1, Iter1, Iter1, const C&, const A1&>);
+ static_assert(!std::is_constructible_v<M1, Iter1, Iter1, const C&, const A2&>);
+ static_assert(!std::is_constructible_v<M2, Iter2, Iter2, const C&, const A2&>);
+ static_assert(!std::is_constructible_v<M3, Iter3, Iter3, const C&, const A2&>);
+ }
+
+ using P = std::pair<int, short>;
+ P ar[] = {{1, 1}, {1, 2}, {1, 3}, {2, 4}, {2, 5}, {3, 6}, {2, 7}, {3, 8}, {3, 9}};
+ P expected[] = {{1, 1}, {1, 2}, {1, 3}, {2, 4}, {2, 5}, {2, 7}, {3, 6}, {3, 8}, {3, 9}};
+ {
+ // flat_multimap(InputIterator , InputIterator)
+ // cpp17_input_iterator
+ using M = std::flat_multimap<int, short>;
+ auto m = M(cpp17_input_iterator<const P*>(ar), cpp17_input_iterator<const P*>(ar + 9));
+ assert(std::ranges::equal(m.keys(), expected | std::views::elements<0>));
+ LIBCPP_ASSERT(std::ranges::equal(m, expected));
+
+ // explicit(false)
+ M m2 = {cpp17_input_iterator<const P*>(ar), cpp17_input_iterator<const P*>(ar + 9)};
+ assert(m2 == m);
+ }
+ {
+ // flat_multimap(InputIterator , InputIterator)
+ // greater
+ using M = std::flat_multimap<int, short, std::greater<int>, std::deque<int, min_allocator<int>>, std::deque<short>>;
+ auto m = M(cpp17_input_iterator<const P*>(ar), cpp17_input_iterator<const P*>(ar + 9));
+ assert((m.keys() == std::deque<int, min_allocator<int>>{3, 3, 3, 2, 2, 2, 1, 1, 1}));
+ LIBCPP_ASSERT((m.values() == std::deque<short>{6, 8, 9, 4, 5, 7, 1, 2, 3}));
+ }
+ {
+ // flat_multimap(InputIterator , InputIterator)
+ // Test when the operands are of array type (also contiguous iterator type)
+ using M = std::flat_multimap<int, short, std::greater<int>, std::vector<int, min_allocator<int>>>;
+ auto m = M(ar, ar);
+ assert(m.empty());
+ }
+ {
+ // flat_multimap(InputIterator , InputIterator, const key_compare&)
+ using C = test_less<int>;
+ using M = std::flat_multimap<int, short, C, std::vector<int>, std::deque<short>>;
+ auto m = M(ar, ar + 9, C(3));
+ assert(std::ranges::equal(m.keys(), expected | std::views::elements<0>));
+ LIBCPP_ASSERT(std::ranges::equal(m, expected));
+ assert(m.key_comp() == C(3));
+
+ // explicit(false)
+ M m2 = {ar, ar + 9, C(3)};
+ assert(m2 == m);
+ assert(m2.key_comp() == C(3));
+ }
+ {
+ // flat_multimap(InputIterator , InputIterator, const Allocator&)
+ using A1 = test_allocator<int>;
+ using A2 = test_allocator<short>;
+ using M = std::flat_multimap<int, short, std::less<int>, std::vector<int, A1>, std::deque<short, A2>>;
+ auto m = M(ar, ar + 9, A1(5));
+ assert(std::ranges::equal(m.keys(), expected | std::views::elements<0>));
+ LIBCPP_ASSERT(std::ranges::equal(m, expected));
+ assert(m.keys().get_allocator() == A1(5));
+ assert(m.values().get_allocator() == A2(5));
+ }
+ {
+ // flat_multimap(InputIterator , InputIterator, const Allocator&)
+ // explicit(false)
+ using A1 = test_allocator<int>;
+ using A2 = test_allocator<short>;
+ using M = std::flat_multimap<int, short, std::less<int>, std::vector<int, A1>, std::deque<short, A2>>;
+ M m = {ar, ar + 9, A1(5)}; // implicit ctor
+ assert(std::ranges::equal(m.keys(), expected | std::views::elements<0>));
+ LIBCPP_ASSERT(std::ranges::equal(m, expected));
+ assert(m.keys().get_allocator() == A1(5));
+ assert(m.values().get_allocator() == A2(5));
+ }
+ {
+ // flat_multimap(InputIterator , InputIterator, const key_compare&, const Allocator&)
+ using C = test_less<int>;
+ using A1 = test_allocator<int>;
+ using A2 = test_allocator<short>;
+ using M = std::flat_multimap<int, short, C, std::vector<int, A1>, std::deque<short, A2>>;
+ auto m = M(ar, ar + 9, C(3), A1(5));
+ assert(std::ranges::equal(m.keys(), expected | std::views::elements<0>));
+ LIBCPP_ASSERT(std::ranges::equal(m, expected));
+ assert(m.key_comp() == C(3));
+ assert(m.keys().get_allocator() == A1(5));
+ assert(m.values().get_allocator() == A2(5));
+ }
+ {
+ // flat_multimap(InputIterator , InputIterator, const key_compare&, const Allocator&)
+ // explicit(false)
+ using A1 = test_allocator<int>;
+ using A2 = test_allocator<short>;
+ using M = std::flat_multimap<int, short, std::less<int>, std::deque<int, A1>, std::vector<short, A2>>;
+ M m = {ar, ar + 9, {}, A2(5)}; // implicit ctor
+ assert(std::ranges::equal(m.keys(), expected | std::views::elements<0>));
+ LIBCPP_ASSERT(std::ranges::equal(m, expected));
+ assert(m.keys().get_allocator() == A1(5));
+ assert(m.values().get_allocator() == A2(5));
+ }
+
+ return 0;
+}
diff --git a/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.cons/move.pass.cpp b/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.cons/move.pass.cpp
new file mode 100644
index 0000000000000..893c9247959d6
--- /dev/null
+++ b/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.cons/move.pass.cpp
@@ -0,0 +1,89 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+// UNSUPPORTED: c++03, c++11, c++14, c++17, c++20
+
+// <flat_map>
+
+// flat_multimap(flat_multimap&&);
+
+#include <algorithm>
+#include <deque>
+#include <flat_map>
+#include <functional>
+#include <utility>
+#include <vector>
+
+#include "../helpers.h"
+#include "test_macros.h"
+#include "../../../test_compare.h"
+#include "test_allocator.h"
+#include "min_allocator.h"
+
+int main(int, char**) {
+ {
+ using C = test_less<int>;
+ using A = test_allocator<int>;
+ using M = std::flat_multimap<int, int, C, std::vector<int, A>, std::deque<int, A>>;
+ M mo = M({{1, 1}, {1, 2}, {3, 1}}, C(5), A(7));
+ M m = std::move(mo);
+ assert((m == M{{1, 1}, {1, 2}, {3, 1}}));
+ assert(m.key_comp() == C(5));
+ assert(m.keys().get_allocator() == A(7));
+ assert(m.values().get_allocator() == A(7));
+
+ assert(mo.empty());
+ assert(mo.key_comp() == C(5));
+ assert(mo.keys().get_allocator().get_id() == test_alloc_base::moved_value);
+ assert(mo.values().get_allocator().get_id() == test_alloc_base::moved_value);
+ }
+ {
+ using C = test_less<int>;
+ using A = min_allocator<int>;
+ using M = std::flat_multimap<int, int, C, std::vector<int, A>, std::deque<int, A>>;
+ M mo = M({{1, 1}, {1, 2}, {3, 1}}, C(5), A());
+ M m = std::move(mo);
+ assert((m == M{{1, 1}, {1, 2}, {3, 1}}));
+ assert(m.key_comp() == C(5));
+ assert(m.keys().get_allocator() == A());
+ assert(m.values().get_allocator() == A());
+
+ assert(mo.empty());
+ assert(mo.key_comp() == C(5));
+ assert(m.keys().get_allocator() == A());
+ assert(m.values().get_allocator() == A());
+ }
+ {
+ // A moved-from flat_multimap maintains its class invariant in the presence of moved-from comparators.
+ using M = std::flat_multimap<int, int, std::function<bool(int, int)>>;
+ M mo = M({{1, 1}, {1, 2}, {3, 1}}, std::less<int>());
+ M m = std::move(mo);
+ assert(m.size() == 3);
+ assert(std::is_sorted(m.begin(), m.end(), m.value_comp()));
+ assert(m.key_comp()(1, 2) == true);
+
+ assert(std::is_sorted(mo.begin(), mo.end(), mo.value_comp()));
+ LIBCPP_ASSERT(m.key_comp()(1, 2) == true);
+ LIBCPP_ASSERT(mo.empty());
+ mo.insert({{1, 1}, {1, 2}, {3, 1}}); // insert has no preconditions
+ assert(m == mo);
+ }
+ {
+ // moved-from object maintains invariant if one of underlying container does not clear after move
+ using M = std::flat_multimap<int, int, std::less<>, std::vector<int>, CopyOnlyVector<int>>;
+ M m1 = M({1, 1, 3}, {1, 2, 3});
+ M m2 = std::move(m1);
+ assert(m2.size() == 3);
+ check_invariant(m1);
+ LIBCPP_ASSERT(m1.empty());
+ LIBCPP_ASSERT(m1.keys().size() == 0);
+ LIBCPP_ASSERT(m1.values().size() == 0);
+ }
+
+ return 0;
+}
diff --git a/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.cons/move_alloc.pass.cpp b/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.cons/move_alloc.pass.cpp
new file mode 100644
index 0000000000000..a0259e805ac5a
--- /dev/null
+++ b/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.cons/move_alloc.pass.cpp
@@ -0,0 +1,82 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+// UNSUPPORTED: c++03, c++11, c++14, c++17, c++20
+
+// <flat_map>
+
+// flat_multimap(flat_multimap&&, const allocator_type&);
+
+#include <algorithm>
+#include <deque>
+#include <flat_map>
+#include <functional>
+#include <ranges>
+#include <vector>
+
+#include "../helpers.h"
+#include "test_macros.h"
+#include "../../../test_compare.h"
+#include "test_allocator.h"
+
+int main(int, char**) {
+ {
+ // The constructors in this subclause shall not participate in overload
+ // resolution unless uses_allocator_v<key_container_type, Alloc> is true
+ // and uses_allocator_v<mapped_container_type, Alloc> is true.
+
+ using C = test_less<int>;
+ using A1 = test_allocator<int>;
+ using A2 = other_allocator<int>;
+ using V1 = std::vector<int, A1>;
+ using V2 = std::vector<int, A2>;
+ using M1 = std::flat_multimap<int, int, C, V1, V1>;
+ using M2 = std::flat_multimap<int, int, C, V1, V2>;
+ using M3 = std::flat_multimap<int, int, C, V2, V1>;
+ static_assert(std::is_constructible_v<M1, M1&&, const A1&>);
+ static_assert(!std::is_constructible_v<M1, M1&&, const A2&>);
+ static_assert(!std::is_constructible_v<M2, M2&&, const A2&>);
+ static_assert(!std::is_constructible_v<M3, M3&&, const A2&>);
+ }
+ {
+ std::pair<int, int> expected[] = {{1, 1}, {1, 2}, {2, 3}, {2, 2}, {3, 1}};
+ using C = test_less<int>;
+ using A = test_allocator<int>;
+ using M = std::flat_multimap<int, int, C, std::vector<int, A>, std::deque<int, A>>;
+ auto mo = M(expected, expected + 5, C(5), A(7));
+ auto m = M(std::move(mo), A(3));
+
+ assert(m.key_comp() == C(5));
+ assert(m.size() == 5);
+ auto [keys, values] = std::move(m).extract();
+ assert(keys.get_allocator() == A(3));
+ assert(values.get_allocator() == A(3));
+ assert(std::ranges::equal(keys, expected | std::views::elements<0>));
+ assert(std::ranges::equal(values, expected | std::views::elements<1>));
+
+ // The original flat_multimap is moved-from.
+ assert(std::is_sorted(mo.begin(), mo.end(), mo.value_comp()));
+ assert(mo.empty());
+ assert(mo.key_comp() == C(5));
+ assert(mo.keys().get_allocator() == A(7));
+ assert(mo.values().get_allocator() == A(7));
+ }
+ {
+ // moved-from object maintains invariant if one of underlying container does not clear after move
+ using M = std::flat_multimap<int, int, std::less<>, std::vector<int>, CopyOnlyVector<int>>;
+ M m1 = M({1, 1, 3}, {1, 2, 3});
+ M m2(std::move(m1), std::allocator<int>{});
+ assert(m2.size() == 3);
+ check_invariant(m1);
+ LIBCPP_ASSERT(m1.empty());
+ LIBCPP_ASSERT(m1.keys().size() == 0);
+ LIBCPP_ASSERT(m1.values().size() == 0);
+ }
+
+ return 0;
+}
diff --git a/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.cons/move_assign.pass.cpp b/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.cons/move_assign.pass.cpp
new file mode 100644
index 0000000000000..38200d008c78a
--- /dev/null
+++ b/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.cons/move_assign.pass.cpp
@@ -0,0 +1,74 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+// UNSUPPORTED: c++03, c++11, c++14, c++17, c++20
+
+// <flat_map>
+
+// flat_multimap& operator=(flat_multimap&&);
+
+#include <algorithm>
+#include <deque>
+#include <flat_map>
+#include <functional>
+#include <string>
+#include <utility>
+#include <vector>
+
+#include "test_macros.h"
+#include "MoveOnly.h"
+#include "../../../test_compare.h"
+#include "test_allocator.h"
+#include "min_allocator.h"
+
+int main(int, char**) {
+ {
+ using C = test_less<int>;
+ using A1 = test_allocator<int>;
+ using A2 = test_allocator<char>;
+ using M = std::flat_multimap<int, char, C, std::vector<int, A1>, std::vector<char, A2>>;
+ M mo = M({{1, 1}, {1, 3}, {3, 2}}, C(5), A1(7));
+ M m = M({}, C(3), A1(7));
+ m = std::move(mo);
+ assert((m == M{{1, 1}, {1, 3}, {3, 2}}));
+ assert(m.key_comp() == C(5));
+ auto [ks, vs] = std::move(m).extract();
+ assert(ks.get_allocator() == A1(7));
+ assert(vs.get_allocator() == A2(7));
+ assert(mo.empty());
+ }
+ {
+ using C = test_less<int>;
+ using A1 = other_allocator<int>;
+ using A2 = other_allocator<char>;
+ using M = std::flat_multimap<int, char, C, std::deque<int, A1>, std::deque<char, A2>>;
+ M mo = M({{4, 5}, {4, 4}}, C(5), A1(7));
+ M m = M({{1, 1}, {1, 2}, {1, 3}, {4, 4}}, C(3), A1(7));
+ m = std::move(mo);
+ assert((m == M{{4, 5}, {4, 4}}));
+ assert(m.key_comp() == C(5));
+ auto [ks, vs] = std::move(m).extract();
+ assert(ks.get_allocator() == A1(7));
+ assert(vs.get_allocator() == A2(7));
+ assert(mo.empty());
+ }
+ {
+ using A = min_allocator<int>;
+ using M = std::flat_multimap<int, int, std::greater<int>, std::vector<int, A>, std::vector<int, A>>;
+ M mo = M({{5, 1}, {5, 2}, {3, 3}}, A());
+ M m = M({{4, 4}, {4, 3}, {4, 2}, {1, 1}}, A());
+ m = std::move(mo);
+ assert((m == M{{5, 1}, {5, 2}, {3, 3}}));
+ auto [ks, vs] = std::move(m).extract();
+ assert(ks.get_allocator() == A());
+ assert(vs.get_allocator() == A());
+ assert(mo.empty());
+ }
+
+ return 0;
+}
diff --git a/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.cons/move_assign_clears.pass.cpp b/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.cons/move_assign_clears.pass.cpp
new file mode 100644
index 0000000000000..bc65dca32899c
--- /dev/null
+++ b/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.cons/move_assign_clears.pass.cpp
@@ -0,0 +1,101 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+// UNSUPPORTED: c++03, c++11, c++14, c++17, c++20
+
+// <flat_map>
+
+// flat_multimap& operator=(flat_multimap&&);
+// Preserves the class invariant for the moved-from flat_multimap.
+
+#include <algorithm>
+#include <cassert>
+#include <compare>
+#include <flat_map>
+#include <functional>
+#include <utility>
+#include <vector>
+
+#include "../helpers.h"
+#include "test_macros.h"
+
+struct MoveNegates {
+ int value_ = 0;
+ MoveNegates() = default;
+ MoveNegates(int v) : value_(v) {}
+ MoveNegates(MoveNegates&& rhs) : value_(rhs.value_) { rhs.value_ = -rhs.value_; }
+ MoveNegates& operator=(MoveNegates&& rhs) {
+ value_ = rhs.value_;
+ rhs.value_ = -rhs.value_;
+ return *this;
+ }
+ ~MoveNegates() = default;
+ auto operator<=>(const MoveNegates&) const = default;
+};
+
+struct MoveClears {
+ int value_ = 0;
+ MoveClears() = default;
+ MoveClears(int v) : value_(v) {}
+ MoveClears(MoveClears&& rhs) : value_(rhs.value_) { rhs.value_ = 0; }
+ MoveClears& operator=(MoveClears&& rhs) {
+ value_ = rhs.value_;
+ rhs.value_ = 0;
+ return *this;
+ }
+ ~MoveClears() = default;
+ auto operator<=>(const MoveClears&) const = default;
+};
+
+int main(int, char**) {
+ {
+ const std::pair<int, int> expected[] = {{1, 1}, {1, 2}, {3, 3}, {3, 4}, {5, 5}, {6, 6}, {7, 7}, {8, 8}};
+ using M = std::flat_multimap<MoveNegates, int, std::less<MoveNegates>, std::vector<MoveNegates>>;
+ M m = M(expected, expected + 8);
+ M m2 = M(expected, expected + 3);
+
+ m2 = std::move(m);
+
+ assert(std::equal(m2.begin(), m2.end(), expected, expected + 8));
+ LIBCPP_ASSERT(m.empty());
+ check_invariant(m);
+ m.insert({1, 1});
+ m.insert({2, 2});
+ assert(m.contains(1));
+ assert(m.find(2) != m.end());
+ }
+ {
+ const std::pair<int, int> expected[] = {{1, 1}, {1, 2}, {3, 3}, {4, 4}, {5, 5}, {5, 6}, {7, 7}, {8, 8}};
+ using M = std::flat_multimap<MoveClears, int, std::less<MoveClears>, std::vector<MoveClears>>;
+ M m = M(expected, expected + 8);
+ M m2 = M(expected, expected + 3);
+
+ m2 = std::move(m);
+
+ assert(std::equal(m2.begin(), m2.end(), expected, expected + 8));
+ LIBCPP_ASSERT(m.empty());
+ check_invariant(m);
+ m.insert({1, 1});
+ m.insert({2, 2});
+ assert(m.contains(1));
+ assert(m.find(2) != m.end());
+ }
+ {
+ // moved-from object maintains invariant if one of underlying container does not clear after move
+ using M = std::flat_multimap<int, int, std::less<>, std::vector<int>, CopyOnlyVector<int>>;
+ M m1 = M({1, 1, 3}, {1, 2, 3});
+ M m2 = M({1, 1}, {1, 2});
+ m2 = std::move(m1);
+ assert(m2.size() == 3);
+ check_invariant(m1);
+ LIBCPP_ASSERT(m1.empty());
+ LIBCPP_ASSERT(m1.keys().size() == 0);
+ LIBCPP_ASSERT(m1.values().size() == 0);
+ }
+ return 0;
+}
diff --git a/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.cons/move_assign_noexcept.pass.cpp b/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.cons/move_assign_noexcept.pass.cpp
new file mode 100644
index 0000000000000..4eb58313f6f72
--- /dev/null
+++ b/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.cons/move_assign_noexcept.pass.cpp
@@ -0,0 +1,110 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+// UNSUPPORTED: c++03, c++11, c++14, c++17, c++20
+
+// <flat_map>
+
+// flat_multimap& operator=(flat_multimap&& c)
+// noexcept(
+// is_nothrow_move_assignable<key_container_type>::value &&
+// is_nothrow_move_assignable<mapped_container_type>::value &&
+// is_nothrow_copy_assignable<key_compare>::value);
+
+// This tests a conforming extension
+
+#include <flat_map>
+#include <functional>
+#include <memory_resource>
+#include <type_traits>
+#include <vector>
+
+#include "MoveOnly.h"
+#include "test_allocator.h"
+#include "test_macros.h"
+
+struct MoveSensitiveComp {
+ MoveSensitiveComp() noexcept(false) = default;
+ MoveSensitiveComp(const MoveSensitiveComp&) noexcept(false) = default;
+ MoveSensitiveComp(MoveSensitiveComp&& rhs) { rhs.is_moved_from_ = true; }
+ MoveSensitiveComp& operator=(const MoveSensitiveComp&) noexcept = default;
+ MoveSensitiveComp& operator=(MoveSensitiveComp&& rhs) {
+ rhs.is_moved_from_ = true;
+ return *this;
+ }
+ bool operator()(const auto&, const auto&) const { return false; }
+ bool is_moved_from_ = false;
+};
+
+struct MoveThrowsComp {
+ MoveThrowsComp(MoveThrowsComp&&) noexcept(false);
+ MoveThrowsComp(const MoveThrowsComp&) noexcept(true);
+ MoveThrowsComp& operator=(MoveThrowsComp&&) noexcept(false);
+ MoveThrowsComp& operator=(const MoveThrowsComp&) noexcept(true);
+ bool operator()(const auto&, const auto&) const;
+};
+
+int main(int, char**) {
+ {
+ using C = std::flat_multimap<int, int>;
+ LIBCPP_STATIC_ASSERT(std::is_nothrow_move_assignable_v<C>);
+ }
+ {
+ using C =
+ std::flat_multimap<MoveOnly,
+ int,
+ std::less<MoveOnly>,
+ std::vector<MoveOnly, test_allocator<MoveOnly>>,
+ std::vector<int, test_allocator<int>>>;
+ static_assert(!std::is_nothrow_move_assignable_v<C>);
+ }
+ {
+ using C =
+ std::flat_multimap<int,
+ MoveOnly,
+ std::less<int>,
+ std::vector<int, test_allocator<int>>,
+ std::vector<MoveOnly, test_allocator<MoveOnly>>>;
+ static_assert(!std::is_nothrow_move_assignable_v<C>);
+ }
+ {
+ using C =
+ std::flat_multimap<MoveOnly,
+ int,
+ std::less<MoveOnly>,
+ std::vector<MoveOnly, other_allocator<MoveOnly>>,
+ std::vector<int, other_allocator<int>>>;
+ LIBCPP_STATIC_ASSERT(std::is_nothrow_move_assignable_v<C>);
+ }
+ {
+ using C =
+ std::flat_multimap<int,
+ MoveOnly,
+ std::less<int>,
+ std::vector<int, other_allocator<int>>,
+ std::vector<MoveOnly, other_allocator<MoveOnly>>>;
+ LIBCPP_STATIC_ASSERT(std::is_nothrow_move_assignable_v<C>);
+ }
+ {
+ // Test with a comparator that throws on move-assignment.
+ using C = std::flat_multimap<int, int, MoveThrowsComp>;
+ LIBCPP_STATIC_ASSERT(!std::is_nothrow_move_assignable_v<C>);
+ }
+ {
+ // Test with a container that throws on move-assignment.
+ using C = std::flat_multimap<int, int, std::less<int>, std::pmr::vector<int>, std::vector<int>>;
+ static_assert(!std::is_nothrow_move_assignable_v<C>);
+ }
+ {
+ // Test with a container that throws on move-assignment.
+ using C = std::flat_multimap<int, int, std::less<int>, std::vector<int>, std::pmr::vector<int>>;
+ static_assert(!std::is_nothrow_move_assignable_v<C>);
+ }
+
+ return 0;
+}
diff --git a/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.cons/move_exceptions.pass.cpp b/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.cons/move_exceptions.pass.cpp
new file mode 100644
index 0000000000000..c2085e32be532
--- /dev/null
+++ b/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.cons/move_exceptions.pass.cpp
@@ -0,0 +1,71 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+// UNSUPPORTED: c++03, c++11, c++14, c++17, c++20
+// UNSUPPORTED: no-exceptions
+
+// <flat_map>
+
+// flat_multimap(flat_multimap&& s);
+// If any member function in [flat.multimap.defn] exits via an exception, the invariant is restored.
+
+#include <algorithm>
+#include <cassert>
+#include <flat_map>
+#include <functional>
+#include <utility>
+#include <vector>
+
+#include "../helpers.h"
+#include "test_macros.h"
+
+static int countdown = 0;
+
+struct EvilContainer : std::vector<int> {
+ EvilContainer() = default;
+ EvilContainer(EvilContainer&& rhs) {
+ // Throw on move-construction.
+ if (--countdown == 0) {
+ rhs.insert(rhs.end(), 0);
+ rhs.insert(rhs.end(), 0);
+ throw 42;
+ }
+ }
+};
+
+int main(int, char**) {
+ {
+ using M = std::flat_multimap<int, int, std::less<int>, EvilContainer, std::vector<int>>;
+ M mo = {{1, 1}, {1, 2}, {3, 3}};
+ countdown = 1;
+ try {
+ M m = std::move(mo);
+ assert(false); // not reached
+ } catch (int x) {
+ assert(x == 42);
+ }
+ // The source flat_multimap maintains its class invariant.
+ check_invariant(mo);
+ LIBCPP_ASSERT(mo.empty());
+ }
+ {
+ using M = std::flat_multimap<int, int, std::less<int>, std::vector<int>, EvilContainer>;
+ M mo = {{1, 1}, {1, 2}, {3, 3}};
+ countdown = 1;
+ try {
+ M m = std::move(mo);
+ assert(false); // not reached
+ } catch (int x) {
+ assert(x == 42);
+ }
+ // The source flat_multimap maintains its class invariant.
+ check_invariant(mo);
+ LIBCPP_ASSERT(mo.empty());
+ }
+ return 0;
+}
diff --git a/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.cons/move_noexcept.pass.cpp b/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.cons/move_noexcept.pass.cpp
new file mode 100644
index 0000000000000..e038902e26d52
--- /dev/null
+++ b/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.cons/move_noexcept.pass.cpp
@@ -0,0 +1,104 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+// UNSUPPORTED: c++03, c++11, c++14, c++17, c++20
+
+// <flat_map>
+
+// flat_multimap(flat_multimap&&)
+// noexcept(is_nothrow_move_constructible<key_container_type>::value &&
+// is_nothrow_move_constructible<mapped_container_type>::value &&
+// is_nothrow_copy_constructible<key_compare>::value);
+
+// This tests a conforming extension
+
+#include <cassert>
+#include <deque>
+#include <flat_map>
+#include <functional>
+#include <memory>
+#include <type_traits>
+#include <vector>
+
+#include "test_macros.h"
+#include "MoveOnly.h"
+#include "test_allocator.h"
+
+template <class T>
+struct ThrowingMoveAllocator {
+ using value_type = T;
+ explicit ThrowingMoveAllocator() = default;
+ ThrowingMoveAllocator(const ThrowingMoveAllocator&) = default;
+ ThrowingMoveAllocator(ThrowingMoveAllocator&&) noexcept(false) {}
+ T* allocate(std::ptrdiff_t n) { return std::allocator<T>().allocate(n); }
+ void deallocate(T* p, std::ptrdiff_t n) { return std::allocator<T>().deallocate(p, n); }
+ friend bool operator==(ThrowingMoveAllocator, ThrowingMoveAllocator) = default;
+};
+
+struct ThrowingMoveComp {
+ ThrowingMoveComp() = default;
+ ThrowingMoveComp(const ThrowingMoveComp&) noexcept(true) {}
+ ThrowingMoveComp(ThrowingMoveComp&&) noexcept(false) {}
+ bool operator()(const auto&, const auto&) const { return false; }
+};
+
+struct MoveSensitiveComp {
+ MoveSensitiveComp() noexcept(false) = default;
+ MoveSensitiveComp(const MoveSensitiveComp&) noexcept = default;
+ MoveSensitiveComp(MoveSensitiveComp&& rhs) { rhs.is_moved_from_ = true; }
+ MoveSensitiveComp& operator=(const MoveSensitiveComp&) noexcept(false) = default;
+ MoveSensitiveComp& operator=(MoveSensitiveComp&& rhs) {
+ rhs.is_moved_from_ = true;
+ return *this;
+ }
+ bool operator()(const auto&, const auto&) const { return false; }
+ bool is_moved_from_ = false;
+};
+
+int main(int, char**) {
+ {
+ using C = std::flat_multimap<int, int>;
+ LIBCPP_STATIC_ASSERT(std::is_nothrow_move_constructible_v<C>);
+ C c;
+ C d = std::move(c);
+ }
+ {
+ using C = std::flat_multimap<int, int, std::less<int>, std::deque<int, test_allocator<int>>>;
+ LIBCPP_STATIC_ASSERT(std::is_nothrow_move_constructible_v<C>);
+ C c;
+ C d = std::move(c);
+ }
+#if _LIBCPP_VERSION
+ {
+ // Container fails to be nothrow-move-constructible; this relies on libc++'s support for non-nothrow-copyable allocators
+ using C =
+ std::flat_multimap<int, int, std::less<int>, std::deque<int, ThrowingMoveAllocator<int>>, std::vector<int>>;
+ static_assert(!std::is_nothrow_move_constructible_v<std::deque<int, ThrowingMoveAllocator<int>>>);
+ static_assert(!std::is_nothrow_move_constructible_v<C>);
+ C c;
+ C d = std::move(c);
+ }
+ {
+ // Container fails to be nothrow-move-constructible; this relies on libc++'s support for non-nothrow-copyable allocators
+ using C =
+ std::flat_multimap<int, int, std::less<int>, std::vector<int>, std::deque<int, ThrowingMoveAllocator<int>>>;
+ static_assert(!std::is_nothrow_move_constructible_v<std::deque<int, ThrowingMoveAllocator<int>>>);
+ static_assert(!std::is_nothrow_move_constructible_v<C>);
+ C c;
+ C d = std::move(c);
+ }
+#endif // _LIBCPP_VERSION
+ {
+ // Comparator fails to be nothrow-move-constructible
+ using C = std::flat_multimap<int, int, ThrowingMoveComp>;
+ static_assert(!std::is_nothrow_move_constructible_v<C>);
+ C c;
+ C d = std::move(c);
+ }
+ return 0;
+}
diff --git a/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.cons/pmr.pass.cpp b/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.cons/pmr.pass.cpp
new file mode 100644
index 0000000000000..8b518f6afbda9
--- /dev/null
+++ b/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.cons/pmr.pass.cpp
@@ -0,0 +1,361 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+// UNSUPPORTED: c++03, c++11, c++14, c++17, c++20
+// UNSUPPORTED: availability-pmr-missing
+
+// <flat_map>
+
+// Test various constructors with pmr
+
+#include <algorithm>
+#include <cassert>
+#include <deque>
+#include <flat_map>
+#include <functional>
+#include <memory_resource>
+#include <ranges>
+#include <vector>
+#include <string>
+
+#include "test_iterators.h"
+#include "test_macros.h"
+#include "test_allocator.h"
+#include "../../../test_compare.h"
+
+int main(int, char**) {
+ {
+ // flat_multimap(const Allocator& a);
+ using M = std::flat_multimap<int, short, std::less<int>, std::pmr::vector<int>, std::pmr::vector<short>>;
+ std::pmr::monotonic_buffer_resource mr;
+ std::pmr::polymorphic_allocator<int> pa = &mr;
+ auto m1 = M(pa);
+ assert(m1.empty());
+ assert(m1.keys().get_allocator() == pa);
+ assert(m1.values().get_allocator() == pa);
+ auto m2 = M(&mr);
+ assert(m2.empty());
+ assert(m2.keys().get_allocator() == pa);
+ assert(m2.values().get_allocator() == pa);
+ }
+ {
+ // flat_multimap(const key_compare& comp, const Alloc& a);
+ using M = std::flat_multimap<int, int, std::function<bool(int, int)>, std::pmr::vector<int>, std::pmr::vector<int>>;
+ std::pmr::monotonic_buffer_resource mr;
+ std::pmr::vector<M> vm(&mr);
+ vm.emplace_back(std::greater<int>());
+ assert(vm[0] == M{});
+ assert(vm[0].key_comp()(2, 1) == true);
+ assert(vm[0].value_comp()({2, 0}, {1, 0}) == true);
+ assert(vm[0].keys().get_allocator().resource() == &mr);
+ assert(vm[0].values().get_allocator().resource() == &mr);
+ }
+ {
+ // flat_multimap(const key_container_type& key_cont, const mapped_container_type& mapped_cont,
+ // const Allocator& a);
+ using M = std::flat_multimap<int, int, std::less<int>, std::pmr::vector<int>, std::pmr::vector<int>>;
+ std::pmr::monotonic_buffer_resource mr;
+ std::pmr::vector<M> vm(&mr);
+ std::pmr::vector<int> ks = {1, 1, 1, 2, 2, 3, 2, 3, 3};
+ std::pmr::vector<int> vs = {1, 1, 1, 2, 2, 3, 2, 3, 3};
+ assert(ks.get_allocator().resource() != &mr);
+ assert(vs.get_allocator().resource() != &mr);
+ vm.emplace_back(ks, vs);
+ assert(ks.size() == 9); // ks' value is unchanged, since it was an lvalue above
+ assert(vs.size() == 9); // vs' value is unchanged, since it was an lvalue above
+ assert((vm[0] == M{{1, 1}, {1, 1}, {1, 1}, {2, 2}, {2, 2}, {2, 2}, {3, 3}, {3, 3}, {3, 3}}));
+ assert(vm[0].keys().get_allocator().resource() == &mr);
+ assert(vm[0].values().get_allocator().resource() == &mr);
+ }
+ {
+ // flat_multimap(const flat_multimap&, const allocator_type&);
+ using C = test_less<int>;
+ using M = std::flat_multimap<int, int, C, std::pmr::vector<int>, std::pmr::vector<int>>;
+ std::pmr::monotonic_buffer_resource mr1;
+ std::pmr::monotonic_buffer_resource mr2;
+ M mo = M({1, 2, 1}, {2, 2, 1}, C(5), &mr1);
+ M m = {mo, &mr2}; // also test the implicitness of this constructor
+
+ assert(m.key_comp() == C(5));
+ assert((m.keys() == std::pmr::vector<int>{1, 1, 2}));
+ assert((m.values() == std::pmr::vector<int>{2, 1, 2}));
+ assert(m.keys().get_allocator().resource() == &mr2);
+ assert(m.values().get_allocator().resource() == &mr2);
+
+ // mo is unchanged
+ assert(mo.key_comp() == C(5));
+ assert((mo.keys() == std::pmr::vector<int>{1, 1, 2}));
+ assert((mo.values() == std::pmr::vector<int>{2, 1, 2}));
+ assert(mo.keys().get_allocator().resource() == &mr1);
+ assert(mo.values().get_allocator().resource() == &mr1);
+ }
+ {
+ // flat_multimap(const flat_multimap&, const allocator_type&);
+ using M = std::flat_multimap<int, int, std::less<>, std::pmr::vector<int>, std::pmr::deque<int>>;
+ std::pmr::vector<M> vs;
+ M m = {{1, 2}, {1, 2}, {3, 1}};
+ vs.push_back(m);
+ assert(vs[0] == m);
+ }
+ {
+ // flat_multimap& operator=(const flat_multimap& m);
+ // pmr allocator is not propagated
+ using M = std::flat_multimap<int, int, std::less<>, std::pmr::deque<int>, std::pmr::vector<int>>;
+ std::pmr::monotonic_buffer_resource mr1;
+ std::pmr::monotonic_buffer_resource mr2;
+ M mo = M({{1, 1}, {1, 2}, {3, 3}}, &mr1);
+ M m = M({{4, 4}, {4, 5}}, &mr2);
+ m = mo;
+ assert((m == M{{1, 1}, {1, 2}, {3, 3}}));
+ assert(m.keys().get_allocator().resource() == &mr2);
+ assert(m.values().get_allocator().resource() == &mr2);
+
+ // mo is unchanged
+ assert((mo == M{{1, 1}, {1, 2}, {3, 3}}));
+ assert(mo.keys().get_allocator().resource() == &mr1);
+ }
+ {
+ // flat_multimap(const flat_multimap& m);
+ using C = test_less<int>;
+ std::pmr::monotonic_buffer_resource mr;
+ using M = std::flat_multimap<int, int, C, std::pmr::vector<int>, std::pmr::vector<int>>;
+ auto mo = M({{1, 1}, {1, 2}, {3, 3}}, C(5), &mr);
+ auto m = mo;
+
+ assert(m.key_comp() == C(5));
+ assert((m == M{{1, 1}, {1, 2}, {3, 3}}));
+ auto [ks, vs] = std::move(m).extract();
+ assert(ks.get_allocator().resource() == std::pmr::get_default_resource());
+ assert(vs.get_allocator().resource() == std::pmr::get_default_resource());
+
+ // mo is unchanged
+ assert(mo.key_comp() == C(5));
+ assert((mo == M{{1, 1}, {1, 2}, {3, 3}}));
+ auto [kso, vso] = std::move(mo).extract();
+ assert(kso.get_allocator().resource() == &mr);
+ assert(vso.get_allocator().resource() == &mr);
+ }
+ {
+ // flat_multimap(initializer_list<value_type> il, const Alloc& a);
+ using M = std::flat_multimap<int, int, std::less<int>, std::pmr::vector<int>, std::pmr::vector<int>>;
+ std::pmr::monotonic_buffer_resource mr;
+ std::pmr::vector<M> vm(&mr);
+ std::initializer_list<M::value_type> il = {{3, 3}, {1, 1}, {4, 4}, {1, 1}, {5, 5}};
+ vm.emplace_back(il);
+ assert((vm[0] == M{{1, 1}, {1, 1}, {3, 3}, {4, 4}, {5, 5}}));
+ assert(vm[0].keys().get_allocator().resource() == &mr);
+ assert(vm[0].values().get_allocator().resource() == &mr);
+ }
+ {
+ // flat_multimap(initializer_list<value_type> il, const key_compare& comp, const Alloc& a);
+ using C = test_less<int>;
+ using M = std::flat_multimap<int, int, C, std::pmr::vector<int>, std::pmr::deque<int>>;
+ std::pmr::monotonic_buffer_resource mr;
+ std::pmr::vector<M> vm(&mr);
+ std::initializer_list<M::value_type> il = {{3, 3}, {1, 1}, {4, 4}, {1, 1}, {5, 5}};
+ vm.emplace_back(il, C(5));
+ assert((vm[0] == M{{1, 1}, {1, 1}, {3, 3}, {4, 4}, {5, 5}}));
+ assert(vm[0].keys().get_allocator().resource() == &mr);
+ assert(vm[0].values().get_allocator().resource() == &mr);
+ assert(vm[0].key_comp() == C(5));
+ }
+ {
+ // flat_multimap(InputIterator first, InputIterator last, const Allocator& a);
+ using P = std::pair<int, short>;
+ P ar[] = {{1, 1}, {1, 2}, {1, 3}, {2, 4}, {2, 5}, {3, 6}, {2, 7}, {3, 8}, {3, 9}};
+ P expected[] = {{1, 1}, {1, 2}, {1, 3}, {2, 4}, {2, 5}, {2, 7}, {3, 6}, {3, 8}, {3, 9}};
+ {
+ // cpp17 iterator
+ using M = std::flat_multimap<int, short, std::less<int>, std::pmr::vector<int>, std::pmr::vector<short>>;
+ std::pmr::monotonic_buffer_resource mr;
+ std::pmr::vector<M> vm(&mr);
+ vm.emplace_back(cpp17_input_iterator<const P*>(ar), cpp17_input_iterator<const P*>(ar + 9));
+ assert(std::ranges::equal(vm[0].keys(), expected | std::views::elements<0>));
+ LIBCPP_ASSERT(std::ranges::equal(vm[0], expected));
+ assert(vm[0].keys().get_allocator().resource() == &mr);
+ assert(vm[0].values().get_allocator().resource() == &mr);
+ }
+ {
+ using M = std::flat_multimap<int, short, std::less<int>, std::pmr::vector<int>, std::pmr::vector<short>>;
+ std::pmr::monotonic_buffer_resource mr;
+ std::pmr::vector<M> vm(&mr);
+ vm.emplace_back(ar, ar);
+ assert(vm[0].empty());
+ assert(vm[0].keys().get_allocator().resource() == &mr);
+ assert(vm[0].values().get_allocator().resource() == &mr);
+ }
+ }
+ {
+ // flat_multimap(flat_multimap&&, const allocator_type&);
+ std::pair<int, int> expected[] = {{1, 1}, {1, 1}, {2, 2}, {3, 1}};
+ using C = test_less<int>;
+ using M = std::flat_multimap<int, int, C, std::pmr::vector<int>, std::pmr::deque<int>>;
+ std::pmr::monotonic_buffer_resource mr1;
+ std::pmr::monotonic_buffer_resource mr2;
+ M mo = M({{1, 1}, {3, 1}, {1, 1}, {2, 2}}, C(5), &mr1);
+ M m = {std::move(mo), &mr2}; // also test the implicitness of this constructor
+
+ assert(m.key_comp() == C(5));
+ assert(m.size() == 4);
+ assert(m.keys().get_allocator().resource() == &mr2);
+ assert(m.values().get_allocator().resource() == &mr2);
+ assert(std::ranges::equal(m, expected));
+
+ // The original flat_multimap is moved-from.
+ assert(std::is_sorted(mo.begin(), mo.end(), mo.value_comp()));
+ assert(mo.key_comp() == C(5));
+ assert(mo.keys().get_allocator().resource() == &mr1);
+ assert(mo.values().get_allocator().resource() == &mr1);
+ }
+ {
+ // flat_multimap(flat_multimap&&, const allocator_type&);
+ using M = std::flat_multimap<int, int, std::less<>, std::pmr::deque<int>, std::pmr::vector<int>>;
+ std::pmr::vector<M> vs;
+ M m = {{1, 1}, {3, 1}, {1, 1}, {2, 2}};
+ vs.push_back(std::move(m));
+ assert((vs[0].keys() == std::pmr::deque<int>{1, 1, 2, 3}));
+ assert((vs[0].values() == std::pmr::vector<int>{1, 1, 2, 1}));
+ }
+ {
+ // flat_multimap& operator=(flat_multimap&&);
+ using M = std::
+ flat_multimap<std::pmr::string, int, std::less<>, std::pmr::vector<std::pmr::string>, std::pmr::vector<int>>;
+ std::pmr::monotonic_buffer_resource mr1;
+ std::pmr::monotonic_buffer_resource mr2;
+ M mo = M({{"short", 1},
+ {"very long string that definitely won't fit in the SSO buffer and therefore becomes empty on move", 2}},
+ &mr1);
+ M m = M({{"don't care", 3}}, &mr2);
+ m = std::move(mo);
+ assert(m.size() == 2);
+ assert(std::is_sorted(m.begin(), m.end(), m.value_comp()));
+ assert(m.begin()->first.get_allocator().resource() == &mr2);
+
+ assert(std::is_sorted(mo.begin(), mo.end(), mo.value_comp()));
+ mo.insert({"foo", 1});
+ assert(mo.begin()->first.get_allocator().resource() == &mr1);
+ }
+ {
+ // flat_multimap(from_range_t, R&&, const Alloc&);
+ using P = std::pair<int, short>;
+ P ar[] = {{1, 1}, {1, 2}, {1, 3}, {2, 4}, {2, 5}, {3, 6}, {2, 7}, {3, 8}, {3, 9}};
+ P expected[] = {{1, 1}, {1, 2}, {1, 3}, {2, 4}, {2, 5}, {2, 7}, {3, 6}, {3, 8}, {3, 9}};
+ {
+ // input_range
+ using M = std::flat_multimap<int, short, std::less<int>, std::pmr::vector<int>, std::pmr::vector<short>>;
+ using Iter = cpp20_input_iterator<const P*>;
+ using Sent = sentinel_wrapper<Iter>;
+ using R = std::ranges::subrange<Iter, Sent>;
+ std::pmr::monotonic_buffer_resource mr;
+ std::pmr::vector<M> vm(&mr);
+ vm.emplace_back(std::from_range, R(Iter(ar), Sent(Iter(ar + 9))));
+ assert(std::ranges::equal(vm[0].keys(), expected | std::views::elements<0>));
+ LIBCPP_ASSERT(std::ranges::equal(vm[0], expected));
+ assert(vm[0].keys().get_allocator().resource() == &mr);
+ assert(vm[0].values().get_allocator().resource() == &mr);
+ }
+ {
+ using M = std::flat_multimap<int, short, std::less<int>, std::pmr::vector<int>, std::pmr::vector<short>>;
+ using R = std::ranges::subrange<const P*>;
+ std::pmr::monotonic_buffer_resource mr;
+ std::pmr::vector<M> vm(&mr);
+ vm.emplace_back(std::from_range, R(ar, ar));
+ assert(vm[0].empty());
+ assert(vm[0].keys().get_allocator().resource() == &mr);
+ assert(vm[0].values().get_allocator().resource() == &mr);
+ }
+ }
+ {
+ // flat_multimap(sorted_equivalent_t, const key_container_type& key_cont,
+ // const mapped_container_type& mapped_cont, const Alloc& a);
+ using M = std::flat_multimap<int, int, std::less<int>, std::pmr::vector<int>, std::pmr::vector<int>>;
+ std::pmr::monotonic_buffer_resource mr;
+ std::pmr::vector<M> vm(&mr);
+ std::pmr::vector<int> ks = {1, 1, 4, 10};
+ std::pmr::vector<int> vs = {4, 3, 2, 1};
+ vm.emplace_back(std::sorted_equivalent, ks, vs);
+ assert(!ks.empty()); // it was an lvalue above
+ assert(!vs.empty()); // it was an lvalue above
+ assert((vm[0] == M{{1, 4}, {1, 3}, {4, 2}, {10, 1}}));
+ assert(vm[0].keys().get_allocator().resource() == &mr);
+ assert(vm[0].values().get_allocator().resource() == &mr);
+ }
+ {
+ // flat_multimap(sorted_equivalent_t, const key_container_type& key_cont,
+ // const mapped_container_type& mapped_cont, const Alloc& a);
+ using M = std::flat_multimap<int, int, std::less<int>, std::pmr::vector<int>, std::pmr::vector<int>>;
+ std::pmr::monotonic_buffer_resource mr;
+ std::pmr::vector<M> vm(&mr);
+ std::pmr::vector<int> ks({1, 1, 4, 10}, &mr);
+ std::pmr::vector<int> vs({4, 3, 2, 1}, &mr);
+ vm.emplace_back(std::sorted_equivalent, ks, vs);
+ assert((vm[0] == M{{1, 4}, {1, 3}, {4, 2}, {10, 1}}));
+ assert(vm[0].keys().get_allocator().resource() == &mr);
+ assert(vm[0].values().get_allocator().resource() == &mr);
+ }
+ {
+ // flat_multimap(sorted_equivalent_t, initializer_list<value_type> il, const Alloc& a);
+ // cpp_17
+ using C = test_less<int>;
+ using M = std::flat_multimap<int, int, C, std::pmr::vector<int>, std::pmr::vector<int>>;
+ std::pmr::monotonic_buffer_resource mr;
+ std::pmr::vector<M> vm(&mr);
+ using P = std::pair<int, int>;
+ P ar[] = {{1, 1}, {1, 2}, {1, 4}, {5, 5}};
+ vm.emplace_back(
+ std::sorted_equivalent, cpp17_input_iterator<const P*>(ar), cpp17_input_iterator<const P*>(ar + 4), C(3));
+ assert((vm[0] == M{{1, 1}, {1, 2}, {1, 4}, {5, 5}}));
+ assert(vm[0].key_comp() == C(3));
+ assert(vm[0].keys().get_allocator().resource() == &mr);
+ assert(vm[0].values().get_allocator().resource() == &mr);
+ }
+ {
+ // flat_multimap(sorted_equivalent_t, initializer_list<value_type> il, const Alloc& a);
+ using C = test_less<int>;
+ using M = std::flat_multimap<int, int, C, std::pmr::vector<int>, std::pmr::vector<int>>;
+ std::pmr::monotonic_buffer_resource mr;
+ std::pmr::vector<M> vm(&mr);
+ std::pair<int, int> ar[1] = {{42, 42}};
+ vm.emplace_back(std::sorted_equivalent, ar, ar, C(4));
+ assert(vm[0] == M{});
+ assert(vm[0].key_comp() == C(4));
+ assert(vm[0].keys().get_allocator().resource() == &mr);
+ assert(vm[0].values().get_allocator().resource() == &mr);
+ }
+ {
+ // flat_multimap(InputIterator first, InputIterator last, const Alloc& a);
+ // cpp_17
+ using C = test_less<int>;
+ using M = std::flat_multimap<int, int, C, std::pmr::vector<int>, std::pmr::vector<int>>;
+ std::pmr::monotonic_buffer_resource mr;
+ std::pmr::vector<M> vm(&mr);
+ using P = std::pair<int, int>;
+ P ar[] = {{1, 1}, {1, 2}, {1, 4}, {5, 5}};
+ vm.emplace_back(
+ std::sorted_equivalent, cpp17_input_iterator<const P*>(ar), cpp17_input_iterator<const P*>(ar + 4), C(3));
+ assert((vm[0] == M{{1, 1}, {1, 2}, {1, 4}, {5, 5}}));
+ assert(vm[0].key_comp() == C(3));
+ assert(vm[0].keys().get_allocator().resource() == &mr);
+ assert(vm[0].values().get_allocator().resource() == &mr);
+ }
+ {
+ // flat_multimap(InputIterator first, InputIterator last, const Alloc& a);
+ using C = test_less<int>;
+ using M = std::flat_multimap<int, int, C, std::pmr::vector<int>, std::pmr::vector<int>>;
+ std::pmr::monotonic_buffer_resource mr;
+ std::pmr::vector<M> vm(&mr);
+ std::pair<int, int> ar[1] = {{42, 42}};
+ vm.emplace_back(std::sorted_equivalent, ar, ar, C(4));
+ assert(vm[0] == M{});
+ assert(vm[0].key_comp() == C(4));
+ assert(vm[0].keys().get_allocator().resource() == &mr);
+ assert(vm[0].values().get_allocator().resource() == &mr);
+ }
+
+ return 0;
+}
diff --git a/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.cons/range.pass.cpp b/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.cons/range.pass.cpp
new file mode 100644
index 0000000000000..de750e2506341
--- /dev/null
+++ b/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.cons/range.pass.cpp
@@ -0,0 +1,227 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+// UNSUPPORTED: c++03, c++11, c++14, c++17, c++20
+
+// <flat_map>
+
+// template<container-compatible-range<value_type> R>
+// flat_multimap(from_range_t, R&&)
+// template<container-compatible-range<value_type> R>
+// flat_multimap(from_range_t, R&&, const key_compare&)
+// template<container-compatible-range<value_type> R, class Alloc>
+// flat_multimap(from_range_t, R&&, const Alloc&);
+// template<container-compatible-range<value_type> R, class Alloc>
+// flat_multimap(from_range_t, R&&, const key_compare&, const Alloc&);
+
+#include <algorithm>
+#include <deque>
+#include <flat_map>
+#include <functional>
+#include <string>
+#include <vector>
+
+#include "min_allocator.h"
+#include "test_allocator.h"
+#include "test_iterators.h"
+#include "test_macros.h"
+#include "../../../test_compare.h"
+
+// test constraint container-compatible-range
+
+template <class V>
+using RangeOf = std::ranges::subrange<V*>;
+using Map = std::flat_multimap<int, double>;
+
+static_assert(std::is_constructible_v<Map, std::from_range_t, RangeOf<std::pair<int, double>>>);
+static_assert(std::is_constructible_v<Map, std::from_range_t, RangeOf<std::pair<short, double>>>);
+static_assert(!std::is_constructible_v<Map, std::from_range_t, RangeOf<int>>);
+static_assert(!std::is_constructible_v<Map, std::from_range_t, RangeOf<double>>);
+
+static_assert(std::is_constructible_v<Map, std::from_range_t, RangeOf<std::pair<int, double>>, std::less<int>>);
+static_assert(std::is_constructible_v<Map, std::from_range_t, RangeOf<std::pair<short, double>>, std::less<int>>);
+static_assert(!std::is_constructible_v<Map, std::from_range_t, RangeOf<int>, std::less<int>>);
+static_assert(!std::is_constructible_v<Map, std::from_range_t, RangeOf<double>, std::less<int>>);
+
+static_assert(std::is_constructible_v<Map, std::from_range_t, RangeOf<std::pair<int, double>>, std::allocator<int>>);
+static_assert(std::is_constructible_v<Map, std::from_range_t, RangeOf<std::pair<short, double>>, std::allocator<int>>);
+static_assert(!std::is_constructible_v<Map, std::from_range_t, RangeOf<int>, std::allocator<int>>);
+static_assert(!std::is_constructible_v<Map, std::from_range_t, RangeOf<double>, std::allocator<int>>);
+
+static_assert(std::is_constructible_v<Map,
+ std::from_range_t,
+ RangeOf<std::pair<int, double>>,
+ std::less<int>,
+ std::allocator<int>>);
+static_assert(std::is_constructible_v<Map,
+ std::from_range_t,
+ RangeOf<std::pair<short, double>>,
+ std::less<int>,
+ std::allocator<int>>);
+static_assert(!std::is_constructible_v<Map, std::from_range_t, RangeOf<int>, std::less<int>, std::allocator<int>>);
+static_assert(!std::is_constructible_v<Map, std::from_range_t, RangeOf<double>, std::less<int>, std::allocator<int>>);
+
+int main(int, char**) {
+ {
+ // The constructors in this subclause shall not participate in overload
+ // resolution unless uses_allocator_v<key_container_type, Alloc> is true
+ // and uses_allocator_v<mapped_container_type, Alloc> is true.
+
+ using C = test_less<int>;
+ using A1 = test_allocator<int>;
+ using A2 = other_allocator<int>;
+ using V1 = std::vector<int, A1>;
+ using V2 = std::vector<int, A2>;
+ using M1 = std::flat_multimap<int, int, C, V1, V1>;
+ using M2 = std::flat_multimap<int, int, C, V1, V2>;
+ using M3 = std::flat_multimap<int, int, C, V2, V1>;
+ static_assert(std::is_constructible_v<M1, std::from_range_t, M1, const A1&>);
+ static_assert(!std::is_constructible_v<M1, std::from_range_t, M1, const A2&>);
+ static_assert(!std::is_constructible_v<M2, std::from_range_t, M2, const A2&>);
+ static_assert(!std::is_constructible_v<M3, std::from_range_t, M3, const A2&>);
+
+ static_assert(std::is_constructible_v<M1, std::from_range_t, M1, const C&, const A1&>);
+ static_assert(!std::is_constructible_v<M1, std::from_range_t, M1, const C&, const A2&>);
+ static_assert(!std::is_constructible_v<M2, std::from_range_t, M2, const C&, const A2&>);
+ static_assert(!std::is_constructible_v<M3, std::from_range_t, M3, const C&, const A2&>);
+ }
+ {
+ // container-compatible-range
+ using C = test_less<int>;
+ using A1 = test_allocator<int>;
+ using A2 = test_allocator<std::string>;
+ using M = std::flat_multimap<int, std::string, C, std::vector<int, A1>, std::vector<std::string, A2>>;
+ using Pair = std::pair<int, std::string>;
+ using PairLike = std::tuple<int, std::string>;
+ using NonPairLike = int;
+
+ static_assert(std::is_constructible_v<M, std::from_range_t, std::vector<Pair>&>);
+ static_assert(std::is_constructible_v<M, std::from_range_t, std::vector<PairLike>&>);
+ static_assert(!std::is_constructible_v<M, std::from_range_t, std::vector<NonPairLike>&>);
+
+ static_assert(std::is_constructible_v<M, std::from_range_t, std::vector<Pair>&, const C&>);
+ static_assert(std::is_constructible_v<M, std::from_range_t, std::vector<PairLike>&, const C&>);
+ static_assert(!std::is_constructible_v<M, std::from_range_t, std::vector<NonPairLike>&, const C&>);
+
+ static_assert(std::is_constructible_v<M, std::from_range_t, std::vector<Pair>&, const A1&>);
+ static_assert(std::is_constructible_v<M, std::from_range_t, std::vector<PairLike>&, const A1&>);
+ static_assert(!std::is_constructible_v<M, std::from_range_t, std::vector<NonPairLike>&, const A1&>);
+
+ static_assert(std::is_constructible_v<M, std::from_range_t, std::vector<Pair>&, const C&, const A1&>);
+ static_assert(std::is_constructible_v<M, std::from_range_t, std::vector<PairLike>&, const C&, const A1&>);
+ static_assert(!std::is_constructible_v<M, std::from_range_t, std::vector<NonPairLike>&, const C&, const A1&>);
+ }
+
+ using P = std::pair<int, short>;
+ P ar[] = {{1, 1}, {1, 2}, {1, 3}, {2, 4}, {2, 5}, {3, 6}, {2, 7}, {3, 8}, {3, 9}};
+ P expected[] = {{1, 1}, {1, 2}, {1, 3}, {2, 4}, {2, 5}, {2, 7}, {3, 6}, {3, 8}, {3, 9}};
+ {
+ // flat_multimap(from_range_t, R&&)
+ // input_range && !common
+ using M = std::flat_multimap<int, short>;
+ using Iter = cpp20_input_iterator<const P*>;
+ using Sent = sentinel_wrapper<Iter>;
+ using R = std::ranges::subrange<Iter, Sent>;
+ auto m = M(std::from_range, R(Iter(ar), Sent(Iter(ar + 9))));
+ assert(std::ranges::equal(m.keys(), expected | std::views::elements<0>));
+ LIBCPP_ASSERT(std::ranges::equal(m, expected));
+
+ // explicit(false)
+ M m2 = {std::from_range, R(Iter(ar), Sent(Iter(ar + 9)))};
+ assert(m2 == m);
+ }
+ {
+ // flat_multimap(from_range_t, R&&)
+ // greater
+ using M = std::flat_multimap<int, short, std::greater<int>, std::deque<int, min_allocator<int>>, std::deque<short>>;
+ using Iter = cpp20_input_iterator<const P*>;
+ using Sent = sentinel_wrapper<Iter>;
+ using R = std::ranges::subrange<Iter, Sent>;
+ auto m = M(std::from_range, R(Iter(ar), Sent(Iter(ar + 9))));
+ assert((m.keys() == std::deque<int, min_allocator<int>>{3, 3, 3, 2, 2, 2, 1, 1, 1}));
+ LIBCPP_ASSERT((m.values() == std::deque<short>{6, 8, 9, 4, 5, 7, 1, 2, 3}));
+ }
+ {
+ // flat_multimap(from_range_t, R&&)
+ // contiguous range
+ using M = std::flat_multimap<int, short>;
+ using R = std::ranges::subrange<const P*>;
+ auto m = M(std::from_range, R(ar, ar + 9));
+ assert(std::ranges::equal(m.keys(), expected | std::views::elements<0>));
+ LIBCPP_ASSERT(std::ranges::equal(m, expected));
+ }
+ {
+ // flat_multimap(from_range_t, R&&, const key_compare&)
+ using C = test_less<int>;
+ using M = std::flat_multimap<int, short, C, std::vector<int>, std::deque<short>>;
+ using R = std::ranges::subrange<const P*>;
+ auto m = M(std::from_range, R(ar, ar + 9), C(3));
+ assert(std::ranges::equal(m.keys(), expected | std::views::elements<0>));
+ LIBCPP_ASSERT(std::ranges::equal(m, expected));
+ assert(m.key_comp() == C(3));
+
+ // explicit(false)
+ M m2 = {std::from_range, R(ar, ar + 9), C(3)};
+ assert(m2 == m);
+ assert(m2.key_comp() == C(3));
+ }
+ {
+ // flat_multimap(from_range_t, R&&, const Allocator&)
+ using A1 = test_allocator<int>;
+ using A2 = test_allocator<short>;
+ using M = std::flat_multimap<int, short, std::less<int>, std::vector<int, A1>, std::deque<short, A2>>;
+ using R = std::ranges::subrange<const P*>;
+ auto m = M(std::from_range, R(ar, ar + 9), A1(5));
+ assert(std::ranges::equal(m.keys(), expected | std::views::elements<0>));
+ LIBCPP_ASSERT(std::ranges::equal(m, expected));
+ assert(m.keys().get_allocator() == A1(5));
+ assert(m.values().get_allocator() == A2(5));
+ }
+ {
+ // flat_multimap(from_range_t, R&&, const Allocator&)
+ // explicit(false)
+ using A1 = test_allocator<int>;
+ using A2 = test_allocator<short>;
+ using M = std::flat_multimap<int, short, std::less<int>, std::vector<int, A1>, std::deque<short, A2>>;
+ using R = std::ranges::subrange<const P*>;
+ M m = {std::from_range, R(ar, ar + 9), A1(5)}; // implicit ctor
+ assert(std::ranges::equal(m.keys(), expected | std::views::elements<0>));
+ LIBCPP_ASSERT(std::ranges::equal(m, expected));
+ assert(m.keys().get_allocator() == A1(5));
+ assert(m.values().get_allocator() == A2(5));
+ }
+ {
+ // flat_multimap(from_range_t, R&&, const key_compare&, const Allocator&)
+ using C = test_less<int>;
+ using A1 = test_allocator<int>;
+ using A2 = test_allocator<short>;
+ using M = std::flat_multimap<int, short, C, std::vector<int, A1>, std::deque<short, A2>>;
+ using R = std::ranges::subrange<const P*>;
+ auto m = M(std::from_range, R(ar, ar + 9), C(3), A1(5));
+ assert(std::ranges::equal(m.keys(), expected | std::views::elements<0>));
+ LIBCPP_ASSERT(std::ranges::equal(m, expected));
+ assert(m.key_comp() == C(3));
+ assert(m.keys().get_allocator() == A1(5));
+ assert(m.values().get_allocator() == A2(5));
+ }
+ {
+ // flat_multimap(from_range_t, R&&, const key_compare&, const Allocator&)
+ // explicit(false)
+ using A1 = test_allocator<int>;
+ using A2 = test_allocator<short>;
+ using M = std::flat_multimap<int, short, std::less<int>, std::deque<int, A1>, std::vector<short, A2>>;
+ using R = std::ranges::subrange<const P*>;
+ M m = {std::from_range, R(ar, ar + 9), {}, A2(5)}; // implicit ctor
+ assert(std::ranges::equal(m.keys(), expected | std::views::elements<0>));
+ LIBCPP_ASSERT(std::ranges::equal(m, expected));
+ assert(m.keys().get_allocator() == A1(5));
+ assert(m.values().get_allocator() == A2(5));
+ }
+
+ return 0;
+}
diff --git a/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.cons/sorted_container.pass.cpp b/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.cons/sorted_container.pass.cpp
new file mode 100644
index 0000000000000..16579f0deed5d
--- /dev/null
+++ b/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.cons/sorted_container.pass.cpp
@@ -0,0 +1,165 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+// UNSUPPORTED: c++03, c++11, c++14, c++17, c++20
+
+// <flat_map>
+
+// flat_multimap(sorted_equivalent_t, key_container_type key_cont, mapped_container_type mapped_cont,
+// const key_compare& comp = key_compare());
+//
+// template<class Alloc>
+// flat_multimap(sorted_equivalent_t, const key_container_type& key_cont,
+// const mapped_container_type& mapped_cont, const Alloc& a);
+// template<class Alloc>
+// flat_multimap(sorted_equivalent_t, const key_container_type& key_cont,
+// const mapped_container_type& mapped_cont,
+// const key_compare& comp, const Alloc& a);
+
+#include <deque>
+#include <flat_map>
+#include <functional>
+#include <vector>
+
+#include "min_allocator.h"
+#include "MoveOnly.h"
+#include "test_allocator.h"
+#include "test_iterators.h"
+#include "test_macros.h"
+#include "../../../test_compare.h"
+
+int main(int, char**) {
+ {
+ // The constructors in this subclause shall not participate in overload
+ // resolution unless uses_allocator_v<key_container_type, Alloc> is true
+ // and uses_allocator_v<mapped_container_type, Alloc> is true.
+
+ using C = test_less<int>;
+ using A1 = test_allocator<int>;
+ using A2 = other_allocator<int>;
+ using V1 = std::vector<int, A1>;
+ using V2 = std::vector<int, A2>;
+ using M1 = std::flat_multimap<int, int, C, V1, V1>;
+ using M2 = std::flat_multimap<int, int, C, V1, V2>;
+ using M3 = std::flat_multimap<int, int, C, V2, V1>;
+ static_assert(std::is_constructible_v<M1, std::sorted_equivalent_t, const V1&, const V1&, const A1&>);
+ static_assert(!std::is_constructible_v<M1, std::sorted_equivalent_t, const V1&, const V1&, const A2&>);
+ static_assert(!std::is_constructible_v<M2, std::sorted_equivalent_t, const V1&, const V2&, const A2&>);
+ static_assert(!std::is_constructible_v<M3, std::sorted_equivalent_t, const V2&, const V1&, const A2&>);
+
+ static_assert(std::is_constructible_v<M1, std::sorted_equivalent_t, const V1&, const V1&, const C&, const A1&>);
+ static_assert(!std::is_constructible_v<M1, std::sorted_equivalent_t, const V1&, const V1&, const C&, const A2&>);
+ static_assert(!std::is_constructible_v<M2, std::sorted_equivalent_t, const V1&, const V2&, const C&, const A2&>);
+ static_assert(!std::is_constructible_v<M3, std::sorted_equivalent_t, const V2&, const V1&, const C&, const A2&>);
+ }
+ {
+ // flat_multimap(sorted_equivalent_t, key_container_type , mapped_container_type)
+ using M = std::flat_multimap<int, char>;
+ std::vector<int> ks = {1, 4, 4, 10};
+ std::vector<char> vs = {4, 3, 2, 1};
+ auto ks2 = ks;
+ auto vs2 = vs;
+
+ auto m = M(std::sorted_equivalent, ks, vs);
+ assert((m == M{{1, 4}, {4, 3}, {4, 2}, {10, 1}}));
+ m = M(std::sorted_equivalent, std::move(ks), std::move(vs));
+ assert(ks.empty()); // it was moved-from
+ assert(vs.empty()); // it was moved-from
+ assert((m == M{{1, 4}, {4, 3}, {4, 2}, {10, 1}}));
+
+ // explicit(false)
+ M m2 = {std::sorted_equivalent, std::move(ks2), std::move(vs2)};
+ assert(m == m2);
+ }
+ {
+ // flat_multimap(sorted_equivalent_t, key_container_type , mapped_container_type)
+ // non-default container, comparator and allocator type
+ using Ks = std::deque<int, min_allocator<int>>;
+ using Vs = std::deque<char, min_allocator<char>>;
+ using M = std::flat_multimap<int, char, std::greater<int>, Ks, Vs>;
+ Ks ks = {10, 1, 1, 1};
+ Vs vs = {1, 2, 3, 4};
+ auto m = M(std::sorted_equivalent, ks, vs);
+ assert((m == M{{1, 2}, {1, 3}, {1, 4}, {10, 1}}));
+ m = M(std::sorted_equivalent, std::move(ks), std::move(vs));
+ assert(ks.empty()); // it was moved-from
+ assert(vs.empty()); // it was moved-from
+ assert((m == M{{1, 2}, {1, 3}, {1, 4}, {10, 1}}));
+ }
+ {
+ // flat_multimap(sorted_equivalent_t, key_container_type , mapped_container_type)
+ // allocator copied into the containers
+ using A = test_allocator<int>;
+ using M = std::flat_multimap<int, int, std::less<int>, std::vector<int, A>, std::deque<int, A>>;
+ auto ks = std::vector<int, A>({2, 2, 4, 10}, A(4));
+ auto vs = std::deque<int, A>({4, 3, 2, 1}, A(5));
+ auto m = M(std::sorted_equivalent, std::move(ks), std::move(vs));
+ assert(ks.empty()); // it was moved-from
+ assert(vs.empty()); // it was moved-from
+ assert((m == M{{2, 4}, {2, 3}, {4, 2}, {10, 1}}));
+ assert(m.keys().get_allocator() == A(4));
+ assert(m.values().get_allocator() == A(5));
+ }
+ {
+ // flat_multimap(sorted_equivalent_t, key_container_type , mapped_container_type, key_compare)
+ using C = test_less<int>;
+ using M = std::flat_multimap<int, char, C>;
+ std::vector<int> ks = {1, 2, 10, 10};
+ std::vector<char> vs = {4, 3, 2, 1};
+
+ auto m = M(std::sorted_equivalent, ks, vs, C(4));
+ assert((m == M{{1, 4}, {2, 3}, {10, 2}, {10, 1}}));
+ assert(m.key_comp() == C(4));
+
+ // explicit(false)
+ M m2 = {std::sorted_equivalent, ks, vs, C(4)};
+ assert(m2 == m);
+ assert(m2.key_comp() == C(4));
+ }
+ {
+ // flat_multimap(sorted_equivalent_t, key_container_type , mapped_container_type, key_compare, const Allocator&)
+ using C = test_less<int>;
+ using A = test_allocator<int>;
+ using M = std::flat_multimap<int, int, C, std::vector<int, A>, std::vector<int, A>>;
+ std::vector<int, A> ks = {1, 2, 4, 10};
+ std::vector<int, A> vs = {4, 3, 2, 1};
+ auto m = M(std::sorted_equivalent, ks, vs, C(4), A(5));
+ assert((m == M{{1, 4}, {2, 3}, {4, 2}, {10, 1}}));
+ assert(m.key_comp() == C(4));
+ assert(m.keys().get_allocator() == A(5));
+ assert(m.values().get_allocator() == A(5));
+
+ // explicit(false)
+ M m2 = {ks, vs, C(4), A(5)};
+ assert(m2 == m);
+ assert(m2.key_comp() == C(4));
+ assert(m2.keys().get_allocator() == A(5));
+ assert(m2.values().get_allocator() == A(5));
+ }
+ {
+ // flat_multimap(sorted_equivalent_t, key_container_type , mapped_container_type, const Allocator&)
+ using A = test_allocator<int>;
+ using M = std::flat_multimap<int, int, std::less<int>, std::vector<int, A>, std::deque<int, A>>;
+ auto ks = std::vector<int, A>({1, 2, 4, 4}, A(4));
+ auto vs = std::deque<int, A>({4, 3, 2, 1}, A(5));
+ auto m = M(std::sorted_equivalent, ks, vs, A(6)); // replaces the allocators
+ assert(!ks.empty()); // it was an lvalue above
+ assert(!vs.empty()); // it was an lvalue above
+ assert((m == M{{1, 4}, {2, 3}, {4, 2}, {4, 1}}));
+ assert(m.keys().get_allocator() == A(6));
+ assert(m.values().get_allocator() == A(6));
+
+ // explicit(false)
+ M m2 = {std::sorted_equivalent, ks, vs, A(6)};
+ assert(m2 == m);
+ assert(m2.keys().get_allocator() == A(6));
+ assert(m2.values().get_allocator() == A(6));
+ }
+
+ return 0;
+}
diff --git a/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.cons/sorted_initializer_list.pass.cpp b/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.cons/sorted_initializer_list.pass.cpp
new file mode 100644
index 0000000000000..b34313bb3d404
--- /dev/null
+++ b/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.cons/sorted_initializer_list.pass.cpp
@@ -0,0 +1,183 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+// UNSUPPORTED: c++03, c++11, c++14, c++17, c++20
+
+// <flat_map>
+
+// template <class InputIterator>
+// flat_multimap(sorted_equivalent_t s, initializer_list<value_type> il,
+// const key_compare& comp = key_compare())
+// template<class Alloc>
+// flat_multimap(sorted_equivalent_t, initializer_list<value_type> il, const Alloc& a);
+// template<class Alloc>
+// flat_multimap(sorted_equivalent_t, initializer_list<value_type> il,
+// const key_compare& comp, const Alloc& a);
+
+#include <deque>
+#include <flat_map>
+#include <functional>
+#include <vector>
+
+#include "min_allocator.h"
+#include "test_allocator.h"
+#include "test_iterators.h"
+#include "test_macros.h"
+#include "../../../test_compare.h"
+
+template <class T, class U>
+std::initializer_list<std::pair<T, U>> il = {{1, 1}, {4, 2}, {4, 4}, {5, 5}};
+
+const auto il1 = il<int, int>;
+const auto il2 = il<int, short>;
+const auto il3 = il<short, int>;
+
+int main(int, char**) {
+ {
+ // The constructors in this subclause shall not participate in overload
+ // resolution unless uses_allocator_v<key_container_type, Alloc> is true
+ // and uses_allocator_v<mapped_container_type, Alloc> is true.
+ using C = test_less<int>;
+ using A1 = test_allocator<int>;
+ using A2 = other_allocator<int>;
+ using V1 = std::vector<int, A1>;
+ using V2 = std::vector<int, A2>;
+ using M1 = std::flat_multimap<int, int, C, V1, V1>;
+ using M2 = std::flat_multimap<int, int, C, V1, V2>;
+ using M3 = std::flat_multimap<int, int, C, V2, V1>;
+ using IL = std::initializer_list<std::pair<int, int>>;
+ static_assert(std::is_constructible_v<M1, std::sorted_equivalent_t, IL, const A1&>);
+ static_assert(!std::is_constructible_v<M1, std::sorted_equivalent_t, IL, const A2&>);
+ static_assert(!std::is_constructible_v<M2, std::sorted_equivalent_t, IL, const A2&>);
+ static_assert(!std::is_constructible_v<M3, std::sorted_equivalent_t, IL, const A2&>);
+
+ static_assert(std::is_constructible_v<M1, std::sorted_equivalent_t, IL, const C&, const A1&>);
+ static_assert(!std::is_constructible_v<M1, std::sorted_equivalent_t, IL, const C&, const A2&>);
+ static_assert(!std::is_constructible_v<M2, std::sorted_equivalent_t, IL, const C&, const A2&>);
+ static_assert(!std::is_constructible_v<M3, std::sorted_equivalent_t, IL, const C&, const A2&>);
+ }
+ {
+ // initializer_list<value_type> needs to match exactly
+ using M = std::flat_multimap<int, short>;
+ using C = typename M::key_compare;
+ static_assert(std::is_constructible_v<M, std::sorted_equivalent_t, std::initializer_list<std::pair<int, short>>>);
+ static_assert(
+ std::is_constructible_v<M, std::sorted_equivalent_t, std::initializer_list<std::pair<int, short>>, C>);
+ static_assert(std::is_constructible_v<M,
+ std::sorted_equivalent_t,
+ std::initializer_list<std::pair<int, short>>,
+ C,
+ std::allocator<int>>);
+ static_assert(std::is_constructible_v<M,
+ std::sorted_equivalent_t,
+ std::initializer_list<std::pair<int, short>>,
+ std::allocator<int>>);
+ static_assert(
+ !std::is_constructible_v<M, std::sorted_equivalent_t, std::initializer_list<std::pair<const int, short>>>);
+ static_assert(
+ !std::is_constructible_v<M, std::sorted_equivalent_t, std::initializer_list<std::pair<const int, short>>, C>);
+ static_assert(!std::is_constructible_v<M,
+ std::sorted_equivalent_t,
+ std::initializer_list<std::pair<const int, short>>,
+ C,
+ std::allocator<int>>);
+ static_assert(!std::is_constructible_v<M,
+ std::sorted_equivalent_t,
+ std::initializer_list<std::pair<const int, short>>,
+ std::allocator<int>>);
+ static_assert(
+ !std::
+ is_constructible_v<M, std::sorted_equivalent_t, std::initializer_list<std::pair<const int, const short>>>);
+ static_assert(!std::is_constructible_v<M,
+ std::sorted_equivalent_t,
+ std::initializer_list<std::pair<const int, const short>>,
+ C>);
+ static_assert(!std::is_constructible_v<M,
+ std::sorted_equivalent_t,
+ std::initializer_list<std::pair<const int, const short>>,
+ C,
+ std::allocator<int>>);
+ static_assert(!std::is_constructible_v<M,
+ std::sorted_equivalent_t,
+ std::initializer_list<std::pair<const int, const short>>,
+ std::allocator<int>>);
+ }
+
+ {
+ // flat_multimap(sorted_equivalent_t, initializer_list<value_type>);
+ using M = std::flat_multimap<int, int>;
+ auto m = M(std::sorted_equivalent, il1);
+ auto expected = M{{1, 1}, {4, 2}, {4, 4}, {5, 5}};
+ assert(m == expected);
+
+ // explicit(false)
+ M m2 = {std::sorted_equivalent, il1};
+ assert(m2 == m);
+ }
+ {
+ // flat_multimap(sorted_equivalent_t, initializer_list<value_type>, const key_compare&);
+ using M = std::flat_multimap<int, int, std::function<bool(int, int)>>;
+ auto m = M(std::sorted_equivalent, il1, std::less<int>());
+ assert(m == M({{1, 1}, {4, 2}, {4, 4}, {5, 5}}, std::less<>()));
+ assert(m.key_comp()(1, 2) == true);
+
+ // explicit(false)
+ M m2 = {std::sorted_equivalent, il1, std::less<int>()};
+ assert(m2 == m);
+ }
+ {
+ // flat_multimap(sorted_equivalent_t, initializer_list<value_type>, const key_compare&);
+ // greater
+ using M = std::flat_multimap<int, int, std::greater<int>, std::deque<int, min_allocator<int>>, std::vector<int>>;
+ std::initializer_list<std::pair<int, int>> il4{{5, 5}, {4, 4}, {1, 2}, {1, 1}};
+ auto m = M(std::sorted_equivalent, il4, std::greater<int>());
+ assert((m == M{{5, 5}, {4, 4}, {1, 2}, {1, 1}}));
+ }
+ {
+ // flat_multimap(sorted_equivalent_t, initializer_list<value_type>, const Allocator&)
+ using A1 = test_allocator<int>;
+ using A2 = test_allocator<short>;
+ using M = std::flat_multimap<int, short, std::less<int>, std::vector<int, A1>, std::deque<short, A2>>;
+ auto m = M(std::sorted_equivalent, il2, A1(5));
+ auto expected = M{{1, 1}, {4, 2}, {4, 4}, {5, 5}};
+ assert(m == expected);
+ assert(m.keys().get_allocator() == A1(5));
+ assert(m.values().get_allocator() == A2(5));
+
+ // explicit(false)
+ M m2 = {std::sorted_equivalent, il2, A1(5)};
+ assert(m2 == m);
+ assert(m2.keys().get_allocator() == A1(5));
+ assert(m2.values().get_allocator() == A2(5));
+ }
+ {
+ // flat_multimap(sorted_equivalent_t, initializer_list<value_type>, const key_compare&, const Allocator&);
+ using C = test_less<int>;
+ using A1 = test_allocator<int>;
+ using A2 = test_allocator<short>;
+ using M = std::flat_multimap<int, short, C, std::vector<int, A1>, std::deque<short, A2>>;
+ auto m = M(std::sorted_equivalent, il2, C(3), A1(5));
+ assert((m == M{{1, 1}, {4, 2}, {4, 4}, {5, 5}}));
+ assert(m.key_comp() == C(3));
+ assert(m.keys().get_allocator() == A1(5));
+ assert(m.values().get_allocator() == A2(5));
+ }
+ {
+ // flat_multimap(sorted_equivalent_t, initializer_list<value_type>, const key_compare&, const Allocator&);
+ // explicit(false)
+ using A1 = test_allocator<short>;
+ using A2 = test_allocator<int>;
+ using M = std::flat_multimap<short, int, std::less<int>, std::deque<short, A1>, std::vector<int, A2>>;
+ M m = {std::sorted_equivalent, il3, {}, A1(5)}; // implicit ctor
+ assert((m == M{{1, 1}, {4, 2}, {4, 4}, {5, 5}}));
+ assert(m.keys().get_allocator() == A1(5));
+ assert(m.values().get_allocator() == A2(5));
+ }
+
+ return 0;
+}
diff --git a/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.cons/sorted_iter_iter.pass.cpp b/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.cons/sorted_iter_iter.pass.cpp
new file mode 100644
index 0000000000000..45c4b3dc675a5
--- /dev/null
+++ b/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.cons/sorted_iter_iter.pass.cpp
@@ -0,0 +1,173 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+// UNSUPPORTED: c++03, c++11, c++14, c++17, c++20
+
+// <flat_map>
+
+// template <class InputIterator>
+// flat_multimap(sorted_equivalent_t, InputIterator first, InputIterator last, const key_compare& comp = key_compare());
+// template<class InputIterator, class Alloc>
+// flat_multimap(InputIterator first, InputIterator last, const Alloc& a);
+// template<class InputIterator, class Allocator>
+// flat_multimap(sorted_equivalent_t, InputIterator first, InputIterator last, const key_compare& comp, const Allocator& a);
+
+#include <deque>
+#include <flat_map>
+#include <functional>
+#include <vector>
+
+#include "min_allocator.h"
+#include "test_allocator.h"
+#include "test_iterators.h"
+#include "test_macros.h"
+#include "../../../test_compare.h"
+
+int main(int, char**) {
+ {
+ // The constructors in this subclause shall not participate in overload
+ // resolution unless uses_allocator_v<key_container_type, Alloc> is true
+ // and uses_allocator_v<mapped_container_type, Alloc> is true.
+ using C = test_less<int>;
+ using A1 = test_allocator<int>;
+ using A2 = other_allocator<int>;
+ using V1 = std::vector<int, A1>;
+ using V2 = std::vector<int, A2>;
+ using M1 = std::flat_multimap<int, int, C, V1, V1>;
+ using M2 = std::flat_multimap<int, int, C, V1, V2>;
+ using M3 = std::flat_multimap<int, int, C, V2, V1>;
+ using Iter1 = typename M1::iterator;
+ using Iter2 = typename M2::iterator;
+ using Iter3 = typename M3::iterator;
+ static_assert(std::is_constructible_v<M1, std::sorted_equivalent_t, Iter1, Iter1, const A1&>);
+ static_assert(!std::is_constructible_v<M1, std::sorted_equivalent_t, Iter1, Iter1, const A2&>);
+ static_assert(!std::is_constructible_v<M2, std::sorted_equivalent_t, Iter2, Iter2, const A2&>);
+ static_assert(!std::is_constructible_v<M3, std::sorted_equivalent_t, Iter3, Iter3, const A2&>);
+
+ static_assert(std::is_constructible_v<M1, std::sorted_equivalent_t, Iter1, Iter1, const C&, const A1&>);
+ static_assert(!std::is_constructible_v<M1, std::sorted_equivalent_t, Iter1, Iter1, const C&, const A2&>);
+ static_assert(!std::is_constructible_v<M2, std::sorted_equivalent_t, Iter2, Iter2, const C&, const A2&>);
+ static_assert(!std::is_constructible_v<M3, std::sorted_equivalent_t, Iter3, Iter3, const C&, const A2&>);
+ }
+ {
+ // flat_multimap(sorted_equivalent_t, InputIterator, InputIterator);
+ // cpp17_input_iterator
+ using M = std::flat_multimap<int, int>;
+ using P = std::pair<int, int>;
+ P ar[] = {{1, 1}, {4, 4}, {5, 5}, {5, 2}};
+ auto m = M(std::sorted_equivalent, cpp17_input_iterator<const P*>(ar), cpp17_input_iterator<const P*>(ar + 4));
+ auto expected = M{{1, 1}, {4, 4}, {5, 5}, {5, 2}};
+ assert(m == expected);
+
+ // explicit(false)
+ M m2 = {std::sorted_equivalent, cpp17_input_iterator<const P*>(ar), cpp17_input_iterator<const P*>(ar + 4)};
+ assert(m2 == m);
+ }
+ {
+ // flat_multimap(sorted_equivalent_t, InputIterator, InputIterator);
+ // contiguous iterator
+ using C = test_less<int>;
+ using M =
+ std::flat_multimap<int, int, C, std::vector<int, min_allocator<int>>, std::vector<int, min_allocator<int>>>;
+ std::pair<int, int> ar[] = {{1, 1}, {1, 4}, {2, 2}, {5, 5}};
+ auto m = M(std::sorted_equivalent, ar, ar + 4);
+ auto expected = M{{1, 1}, {1, 4}, {2, 2}, {5, 5}};
+ assert(m == expected);
+ }
+ {
+ // flat_multimap(sorted_equivalent_t, InputIterator, InputIterator, const key_compare&);
+ // cpp_17_input_iterator
+ using M = std::flat_multimap<int, int, std::function<bool(int, int)>>;
+ using P = std::pair<int, int>;
+ P ar[] = {{1, 1}, {2, 2}, {2, 4}, {5, 5}};
+ auto m = M(std::sorted_equivalent,
+ cpp17_input_iterator<const P*>(ar),
+ cpp17_input_iterator<const P*>(ar + 4),
+ std::less<int>());
+ assert(m == M({{1, 1}, {2, 2}, {2, 4}, {5, 5}}, std::less<>()));
+ assert(m.key_comp()(1, 2) == true);
+
+ // explicit(false)
+ M m2 = {std::sorted_equivalent,
+ cpp17_input_iterator<const P*>(ar),
+ cpp17_input_iterator<const P*>(ar + 4),
+ std::less<int>()};
+ assert(m2 == m);
+ }
+ {
+ // flat_multimap(sorted_equivalent_t, InputIterator, InputIterator, const key_compare&);
+ // greater
+ using M = std::flat_multimap<int, int, std::greater<int>, std::deque<int, min_allocator<int>>, std::vector<int>>;
+ using P = std::pair<int, int>;
+ P ar[] = {{5, 5}, {2, 4}, {2, 2}, {1, 1}};
+ auto m = M(std::sorted_equivalent,
+ cpp17_input_iterator<const P*>(ar),
+ cpp17_input_iterator<const P*>(ar + 4),
+ std::greater<int>());
+ assert((m == M{{5, 5}, {2, 4}, {2, 2}, {1, 1}}));
+ }
+ {
+ // flat_multimap(sorted_equivalent_t, InputIterator, InputIterator, const key_compare&);
+ // contiguous iterator
+ using C = test_less<int>;
+ using M =
+ std::flat_multimap<int, int, C, std::vector<int, min_allocator<int>>, std::vector<int, min_allocator<int>>>;
+ std::pair<int, int> ar[1] = {{42, 42}};
+ auto m = M(std::sorted_equivalent, ar, ar, C(5));
+ assert(m.empty());
+ assert(m.key_comp() == C(5));
+ }
+ {
+ // flat_multimap(sorted_equivalent_t, InputIterator , InputIterator, const Allocator&)
+ using A1 = test_allocator<int>;
+ using A2 = test_allocator<short>;
+ using M = std::flat_multimap<int, short, std::less<int>, std::vector<int, A1>, std::deque<short, A2>>;
+ using P = std::pair<int, int>;
+ P ar[] = {{2, 1}, {2, 2}, {4, 4}, {5, 5}};
+ auto m = M(std::sorted_equivalent, ar, ar + 4, A1(5));
+ auto expected = M{{2, 1}, {2, 2}, {4, 4}, {5, 5}};
+ assert(m == expected);
+ assert(m.keys().get_allocator() == A1(5));
+ assert(m.values().get_allocator() == A2(5));
+
+ // explicit(false)
+ M m2 = {std::sorted_equivalent, ar, ar + 4, A1(5)};
+ assert(m2 == m);
+ assert(m2.keys().get_allocator() == A1(5));
+ assert(m2.values().get_allocator() == A2(5));
+ }
+ {
+ // flat_multimap(sorted_equivalent_t, InputIterator, InputIterator, const key_compare&, const Allocator&);
+ using C = test_less<int>;
+ using A1 = test_allocator<int>;
+ using A2 = test_allocator<short>;
+ using M = std::flat_multimap<int, short, C, std::vector<int, A1>, std::deque<short, A2>>;
+ using P = std::pair<int, int>;
+ P ar[] = {{1, 1}, {1, 2}, {1, 4}, {1, 5}};
+ auto m = M(std::sorted_equivalent, ar, ar + 4, C(3), A1(5));
+ assert((m == M{{1, 1}, {1, 2}, {1, 4}, {1, 5}}));
+ assert(m.key_comp() == C(3));
+ assert(m.keys().get_allocator() == A1(5));
+ assert(m.values().get_allocator() == A2(5));
+ }
+ {
+ // flat_multimap(sorted_equivalent_t, InputIterator, InputIterator, const key_compare&, const Allocator&);
+ // explicit(false)
+ using A1 = test_allocator<short>;
+ using A2 = test_allocator<int>;
+ using M = std::flat_multimap<short, int, std::less<int>, std::deque<short, A1>, std::vector<int, A2>>;
+ using P = std::pair<int, int>;
+ P ar[] = {{1, 1}, {1, 2}, {1, 4}, {1, 5}};
+ M m = {std::sorted_equivalent, ar, ar + 4, {}, A1(5)}; // implicit ctor
+ assert((m == M{{1, 1}, {1, 2}, {1, 4}, {1, 5}}));
+ assert(m.keys().get_allocator() == A1(5));
+ assert(m.values().get_allocator() == A2(5));
+ }
+
+ return 0;
+}
diff --git a/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.erasure/erase_if.pass.cpp b/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.erasure/erase_if.pass.cpp
new file mode 100644
index 0000000000000..76d5cbd909050
--- /dev/null
+++ b/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.erasure/erase_if.pass.cpp
@@ -0,0 +1,98 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+// UNSUPPORTED: c++03, c++11, c++14, c++17, c++20
+
+// <flat_map>
+
+// class flat_multimap
+
+// template<class Key, class T, class Compare, class KeyContainer, class MappedContainer, class Predicate>
+// typename flat_multimap<Key, T, Compare, KeyContainer, MappedContainer>::size_type
+// erase_if(flat_multimap<Key, T, Compare, KeyContainer, MappedContainer>& c, Predicate pred);
+
+#include <deque>
+#include <flat_map>
+#include <functional>
+#include <initializer_list>
+#include <vector>
+
+#include "test_macros.h"
+#include "test_allocator.h"
+#include "min_allocator.h"
+
+// Verify that `flat_multimap` (like `multimap`) does NOT support std::erase.
+//
+template <class S>
+concept HasStdErase = requires(S& s, typename S::value_type x) { std::erase(s, x); };
+static_assert(HasStdErase<std::vector<int>>);
+static_assert(!HasStdErase<std::flat_multimap<int, int>>);
+
+template <class M>
+M make(std::initializer_list<int> vals) {
+ M ret;
+ for (int v : vals) {
+ ret.emplace(static_cast<typename M::key_type>(v), static_cast<typename M::mapped_type>(v + 10));
+ }
+ return ret;
+}
+
+template <class M, class Pred>
+void test0(
+ std::initializer_list<int> vals, Pred p, std::initializer_list<int> expected, std::size_t expected_erased_count) {
+ M s = make<M>(vals);
+ ASSERT_SAME_TYPE(typename M::size_type, decltype(std::erase_if(s, p)));
+ assert(expected_erased_count == std::erase_if(s, p));
+ assert(s == make<M>(expected));
+}
+
+template <class S>
+void test() {
+ // Test all the plausible signatures for this predicate.
+ auto is1 = [](typename S::const_reference v) { return v.first == 1; };
+ auto is2 = [](typename S::value_type v) { return v.first == 2; };
+ auto is3 = [](const typename S::value_type& v) { return v.first == 3; };
+ auto is4 = [](auto v) { return v.first == 4; };
+ auto True = [](const auto&) { return true; };
+ auto False = [](auto&&) { return false; };
+
+ test0<S>({}, is1, {}, 0);
+
+ test0<S>({1}, is1, {}, 1);
+ test0<S>({1, 1}, is1, {}, 2);
+ test0<S>({1, 1}, is2, {1, 1}, 0);
+
+ test0<S>({1, 2}, is1, {2}, 1);
+ test0<S>({1, 2}, is2, {1}, 1);
+ test0<S>({1, 2, 2, 2}, is2, {1}, 3);
+ test0<S>({1, 2, 2, 2}, is3, {1, 2, 2, 2}, 0);
+
+ test0<S>({1, 1, 2, 2, 3, 3}, is1, {2, 2, 3, 3}, 2);
+ test0<S>({1, 1, 2, 2, 3, 3}, is2, {1, 1, 3, 3}, 2);
+ test0<S>({1, 1, 2, 2, 3, 3}, is3, {1, 1, 2, 2}, 2);
+ test0<S>({1, 1, 2, 2, 3, 3}, is4, {1, 1, 2, 2, 3, 3}, 0);
+
+ test0<S>({1, 2, 2, 3, 3, 3}, True, {}, 6);
+ test0<S>({1, 2, 2, 3, 3, 3}, False, {1, 2, 2, 3, 3, 3}, 0);
+}
+
+int main(int, char**) {
+ test<std::flat_multimap<int, char>>();
+ test<std::flat_multimap<int,
+ char,
+ std::less<int>,
+ std::vector<int, min_allocator<int>>,
+ std::vector<char, min_allocator<char>>>>();
+ test<std::flat_multimap<int, char, std::greater<int>, std::vector<int, test_allocator<int>>>>();
+ test<std::flat_multimap<int, char, std::less<int>, std::deque<int, min_allocator<int>>>>();
+ test<std::flat_multimap<int, char, std::greater<int>, std::deque<int, test_allocator<int>>>>();
+ test<std::flat_multimap<long, int>>();
+ test<std::flat_multimap<double, int>>();
+
+ return 0;
+}
diff --git a/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.erasure/erase_if_exceptions.pass.cpp b/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.erasure/erase_if_exceptions.pass.cpp
new file mode 100644
index 0000000000000..13b57202f7862
--- /dev/null
+++ b/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.erasure/erase_if_exceptions.pass.cpp
@@ -0,0 +1,157 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+// UNSUPPORTED: c++03, c++11, c++14, c++17, c++20
+// UNSUPPORTED: no-exceptions
+
+// <flat_map>
+
+// class flat_multimap
+
+// template<class Key, class T, class Compare, class KeyContainer, class MappedContainer, class Predicate>
+// typename flat_multimap<Key, T, Compare, KeyContainer, MappedContainer>::size_type
+// erase_if(flat_multimap<Key, T, Compare, KeyContainer, MappedContainer>& c, Predicate pred);
+// If any member function in [flat.set.defn] exits via an exception, the invariant is restored.
+// (This is not a member function, but let's respect the invariant anyway.)
+
+#include <algorithm>
+#include <cassert>
+#include <deque>
+#include <flat_map>
+#include <functional>
+#include <utility>
+#include <vector>
+
+#include "../helpers.h"
+#include "test_macros.h"
+
+struct Counter {
+ int c1, c2, throws;
+ void tick() {
+ c1 -= 1;
+ if (c1 == 0) {
+ c1 = c2;
+ throws += 1;
+ throw 42;
+ }
+ }
+};
+Counter g_counter = {0, 0, 0};
+
+struct ThrowingAssignment {
+ ThrowingAssignment(int i) : i_(i) {}
+ ThrowingAssignment(const ThrowingAssignment&) = default;
+ ThrowingAssignment& operator=(const ThrowingAssignment& rhs) {
+ g_counter.tick();
+ i_ = rhs.i_;
+ g_counter.tick();
+ return *this;
+ }
+ operator int() const { return i_; }
+ int i_;
+};
+
+struct ThrowingComparator {
+ bool operator()(const ThrowingAssignment& a, const ThrowingAssignment& b) const {
+ g_counter.tick();
+ return a.i_ < b.i_;
+ }
+};
+
+struct ErasurePredicate {
+ bool operator()(const auto& x) const { return (3 <= x.first && x.first <= 5); }
+};
+
+int main(int, char**) {
+ const std::pair<int, int> expected[] = {{1, 1}, {2, 2}, {3, 3}, {3, 3}, {5, 5}, {6, 6}, {7, 7}, {8, 8}};
+ {
+ using M = std::flat_multimap<ThrowingAssignment, int, ThrowingComparator>;
+ for (int first_throw = 1; first_throw < 99; ++first_throw) {
+ for (int second_throw = 1; second_throw < 99; ++second_throw) {
+ g_counter = {0, 0, 0};
+ M m = M({1, 2, 3, 3, 5, 6, 7, 8}, {1, 2, 3, 3, 5, 6, 7, 8});
+ try {
+ g_counter = {first_throw, second_throw, 0};
+ auto n = std::erase_if(m, ErasurePredicate());
+ assert(n == 3);
+ // If it didn't throw at all, we're done.
+ g_counter = {0, 0, 0};
+ assert((m == M{{1, 1}, {2, 2}, {6, 6}, {7, 7}, {8, 8}}));
+ first_throw = 99; // "done"
+ break;
+ } catch (int ex) {
+ assert(ex == 42);
+ check_invariant(m);
+ LIBCPP_ASSERT(m.empty() || std::equal(m.begin(), m.end(), expected, expected + 8));
+ if (g_counter.throws == 1) {
+ // We reached the first throw but not the second throw.
+ break;
+ }
+ }
+ }
+ }
+ }
+ {
+ using M = std::flat_multimap<int, ThrowingAssignment, ThrowingComparator>;
+ for (int first_throw = 1; first_throw < 99; ++first_throw) {
+ for (int second_throw = 1; second_throw < 99; ++second_throw) {
+ g_counter = {0, 0, 0};
+ M m = M({1, 2, 3, 3, 5, 6, 7, 8}, {1, 2, 3, 3, 5, 6, 7, 8});
+ try {
+ g_counter = {first_throw, second_throw, 0};
+ auto n = std::erase_if(m, ErasurePredicate());
+ assert(n == 3);
+ // If it didn't throw at all, we're done.
+ g_counter = {0, 0, 0};
+ assert((m == M{{1, 1}, {2, 2}, {6, 6}, {7, 7}, {8, 8}}));
+ first_throw = 99; // "done"
+ break;
+ } catch (int ex) {
+ assert(ex == 42);
+ check_invariant(m);
+ LIBCPP_ASSERT(m.empty() || std::equal(m.begin(), m.end(), expected, expected + 8));
+ if (g_counter.throws == 1) {
+ // We reached the first throw but not the second throw.
+ break;
+ }
+ }
+ }
+ }
+ }
+ {
+ using M = std::
+ flat_multimap<ThrowingAssignment, int, ThrowingComparator, std::deque<ThrowingAssignment>, std::deque<int>>;
+ for (int first_throw = 1; first_throw < 99; ++first_throw) {
+ for (int second_throw = 1; second_throw < 99; ++second_throw) {
+ g_counter = {0, 0, 0};
+ std::deque<ThrowingAssignment> container = {5, 6, 7, 8};
+ container.insert(container.begin(), {1, 2, 3, 3});
+ M m = M(std::move(container), {1, 2, 3, 3, 5, 6, 7, 8});
+ try {
+ g_counter = {first_throw, second_throw, 0};
+ auto n = std::erase_if(m, ErasurePredicate());
+ assert(n == 3);
+ // If it didn't throw at all, we're done.
+ g_counter = {0, 0, 0};
+ assert((m == M{{1, 1}, {2, 2}, {6, 6}, {7, 7}, {8, 8}}));
+ first_throw = 99; // "done"
+ break;
+ } catch (int ex) {
+ assert(ex == 42);
+ check_invariant(m);
+ LIBCPP_ASSERT(m.empty() || std::equal(m.begin(), m.end(), expected, expected + 8));
+ if (g_counter.throws == 1) {
+ // We reached the first throw but not the second throw.
+ break;
+ }
+ }
+ }
+ }
+ }
+ return 0;
+}
diff --git a/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.iterators/iterator.pass.cpp b/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.iterators/iterator.pass.cpp
new file mode 100644
index 0000000000000..c1285955e5db6
--- /dev/null
+++ b/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.iterators/iterator.pass.cpp
@@ -0,0 +1,105 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+// UNSUPPORTED: c++03, c++11, c++14, c++17, c++20
+
+// <flat_map>
+
+// class flat_multimap
+
+// iterator begin() noexcept;
+// const_iterator begin() const noexcept
+// iterator end() noexcept;
+// const_iterator end() const noexcept;
+//
+// const_iterator cbegin() const noexcept;
+// const_iterator cend() const noexcept;
+
+#include <cassert>
+#include <cstddef>
+#include <deque>
+#include <flat_map>
+#include <functional>
+#include <string>
+
+#include "MinSequenceContainer.h"
+#include "test_macros.h"
+#include "min_allocator.h"
+
+template <class KeyContainer, class ValueContainer>
+void test() {
+ using Key = typename KeyContainer::value_type;
+ using Value = typename ValueContainer::value_type;
+ using M = std::flat_multimap<Key, Value, std::less<Key>, KeyContainer, ValueContainer>;
+
+ M m = {{1, 'a'}, {1, 'z'}, {2, 'b'}, {3, 'a'}, {3, 'b'}, {3, 'c'}, {4, 'd'}};
+ const M& cm = m;
+ ASSERT_SAME_TYPE(decltype(m.begin()), typename M::iterator);
+ ASSERT_SAME_TYPE(decltype(m.cbegin()), typename M::const_iterator);
+ ASSERT_SAME_TYPE(decltype(cm.begin()), typename M::const_iterator);
+ ASSERT_SAME_TYPE(decltype(m.end()), typename M::iterator);
+ ASSERT_SAME_TYPE(decltype(m.cend()), typename M::const_iterator);
+ ASSERT_SAME_TYPE(decltype(cm.end()), typename M::const_iterator);
+ static_assert(noexcept(m.begin()));
+ static_assert(noexcept(cm.begin()));
+ static_assert(noexcept(m.cbegin()));
+ static_assert(noexcept(m.end()));
+ static_assert(noexcept(cm.end()));
+ static_assert(noexcept(m.cend()));
+ assert(m.size() == 7);
+ assert(std::distance(m.begin(), m.end()) == 7);
+ assert(std::distance(cm.begin(), cm.end()) == 7);
+ assert(std::distance(m.cbegin(), m.cend()) == 7);
+ typename M::iterator i; // default-construct
+ i = m.begin(); // move-assignment
+ typename M::const_iterator k = i; // converting constructor
+ assert(i == k); // comparison
+ assert(i->first == 1); // operator->
+ assert(i->second == 'a'); // operator->
+ ++i; // pre-increment
+ assert(i->first == 1); // operator->
+ assert(i->second == 'z'); // operator->
+ i = i + 3; // operator+
+ assert((*i).first == 3); // operator*
+ assert((*i).second == 'b'); // operator*
+ i += 3; // operator+=
+ assert(i == m.end()); // operator==
+ --i; // pre-decrement
+ assert(i->first == 4); // operator->
+ assert(i->second == 'd'); // operator->
+ i = i - 2; // operator-
+ assert(i->first == 3); // operator->
+ assert(i->second == 'b'); // operator->
+ i -= 2; // operator-=
+ assert(i > m.begin()); // operator>
+}
+
+int main(int, char**) {
+ test<std::vector<int>, std::vector<char>>();
+ test<std::deque<int>, std::vector<char>>();
+ test<MinSequenceContainer<int>, MinSequenceContainer<char>>();
+ test<std::vector<int, min_allocator<int>>, std::vector<char, min_allocator<char>>>();
+
+ {
+ // N3644 testing
+ using C = std::flat_multimap<int, char>;
+ C::iterator ii1{}, ii2{};
+ C::iterator ii4 = ii1;
+ C::const_iterator cii{};
+ assert(ii1 == ii2);
+ assert(ii1 == ii4);
+ assert(!(ii1 != ii2));
+
+ assert((ii1 == cii));
+ assert((cii == ii1));
+ assert(!(ii1 != cii));
+ assert(!(cii != ii1));
+ }
+
+ return 0;
+}
diff --git a/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.iterators/iterator_comparison.pass.cpp b/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.iterators/iterator_comparison.pass.cpp
new file mode 100644
index 0000000000000..f1b2cad743e23
--- /dev/null
+++ b/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.iterators/iterator_comparison.pass.cpp
@@ -0,0 +1,155 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+// UNSUPPORTED: c++03, c++11, c++14, c++17, c++20
+
+// <flat_map>
+
+// flat_multimap iterators should be C++20 random access iterators
+
+#include <compare>
+#include <concepts>
+#include <deque>
+#include <flat_map>
+#include <functional>
+#include <vector>
+
+#include "MinSequenceContainer.h"
+#include "test_macros.h"
+#include "min_allocator.h"
+
+template <class KeyContainer, class ValueContainer>
+void test() {
+ using Key = typename KeyContainer::value_type;
+ using Value = typename ValueContainer::value_type;
+ using M = std::flat_multimap<Key, Value, std::less<Key>, KeyContainer, ValueContainer>;
+ using KI = typename KeyContainer::iterator;
+ using I = M::iterator;
+ using CI = M::const_iterator;
+ using RI = M::reverse_iterator;
+ using CRI = M::const_reverse_iterator;
+
+ static_assert(std::equality_comparable<I>);
+ static_assert(std::equality_comparable<CI>);
+ static_assert(std::equality_comparable<RI>);
+ static_assert(std::equality_comparable<CRI>);
+
+ static_assert(std::totally_ordered<I>);
+ static_assert(std::totally_ordered<CI>);
+ static_assert(std::totally_ordered<RI>);
+ static_assert(std::totally_ordered<CRI>);
+
+ M m = {{1, 'a'}, {2, 'b'}, {2, 'e'}, {3, 'z'}, {3, 'y'}, {3, 'c'}, {4, 'd'}};
+
+ I i1 = m.begin();
+ I i2 = m.begin() + 1;
+
+ assert(i1 == i1);
+ assert(!(i1 != i1));
+ assert(i1 != i2);
+ assert(!(i1 == i2));
+ assert(i1 < i2);
+ assert(!(i1 < i1));
+ assert(i1 <= i1);
+ assert(i1 <= i2);
+ assert(!(i2 <= i1));
+ assert(i2 > i1);
+ assert(!(i2 > i2));
+ assert(i2 >= i1);
+ assert(i2 >= i2);
+ assert(!(i1 >= i2));
+
+ CI ci1 = m.cbegin();
+ CI ci2 = m.cbegin() + 1;
+ assert(ci1 == ci1);
+ assert(!(ci1 != ci1));
+ assert(ci1 != ci2);
+ assert(!(ci1 == ci2));
+ assert(ci1 < ci2);
+ assert(!(ci1 < ci1));
+ assert(ci1 <= ci1);
+ assert(ci1 <= ci2);
+ assert(!(ci2 <= ci1));
+ assert(ci2 > ci1);
+ assert(!(ci2 > ci2));
+ assert(ci2 >= ci1);
+ assert(ci2 >= ci2);
+ assert(!(ci1 >= ci2));
+
+ RI ri1 = m.rbegin();
+ RI ri2 = m.rbegin() + 1;
+ assert(ri1 == ri1);
+ assert(!(ri1 != ri1));
+ assert(ri1 != ri2);
+ assert(!(ri1 == ri2));
+ assert(ri1 < ri2);
+ assert(!(ri1 < ri1));
+ assert(ri1 <= ri1);
+ assert(ri1 <= ri2);
+ assert(!(ri2 <= ri1));
+ assert(ri2 > ri1);
+ assert(!(ri2 > ri2));
+ assert(ri2 >= ri1);
+ assert(ri2 >= ri2);
+ assert(!(ri1 >= ri2));
+
+ CRI cri1 = m.crbegin();
+ CRI cri2 = m.crbegin() + 1;
+ assert(cri1 == cri1);
+ assert(!(cri1 != cri1));
+ assert(cri1 != cri2);
+ assert(!(cri1 == cri2));
+ assert(cri1 < cri2);
+ assert(!(cri1 < cri1));
+ assert(cri1 <= cri1);
+ assert(cri1 <= cri2);
+ assert(!(cri2 <= cri1));
+ assert(cri2 > cri1);
+ assert(!(cri2 > cri2));
+ assert(cri2 >= cri1);
+ assert(cri2 >= cri2);
+ assert(!(cri1 >= cri2));
+
+ if constexpr (std::three_way_comparable<KI>) {
+ static_assert(std::three_way_comparable<I>); // ...of course the wrapped iterators still support <=>.
+ static_assert(std::three_way_comparable<CI>);
+ static_assert(std::three_way_comparable<RI>);
+ static_assert(std::three_way_comparable<CRI>);
+ static_assert(std::same_as<decltype(I() <=> I()), std::strong_ordering>);
+ static_assert(std::same_as<decltype(I() <=> CI()), std::strong_ordering>);
+ static_assert(std::same_as<decltype(CI() <=> CI()), std::strong_ordering>);
+ static_assert(std::same_as<decltype(RI() <=> RI()), std::strong_ordering>);
+ static_assert(std::same_as<decltype(RI() <=> CRI()), std::strong_ordering>);
+ static_assert(std::same_as<decltype(CRI() <=> CRI()), std::strong_ordering>);
+
+ assert(i1 <=> i1 == std::strong_ordering::equivalent);
+ assert(i1 <=> i2 == std::strong_ordering::less);
+ assert(i2 <=> i1 == std::strong_ordering::greater);
+
+ assert(ci1 <=> ci1 == std::strong_ordering::equivalent);
+ assert(ci1 <=> ci2 == std::strong_ordering::less);
+ assert(ci2 <=> ci1 == std::strong_ordering::greater);
+
+ assert(ri1 <=> ri1 == std::strong_ordering::equivalent);
+ assert(ri1 <=> ri2 == std::strong_ordering::less);
+ assert(ri2 <=> ri1 == std::strong_ordering::greater);
+
+ assert(cri1 <=> cri1 == std::strong_ordering::equivalent);
+ assert(cri1 <=> cri2 == std::strong_ordering::less);
+ assert(cri2 <=> cri1 == std::strong_ordering::greater);
+ }
+}
+
+int main(int, char**) {
+ test<std::vector<int>, std::vector<char>>();
+ test<std::deque<int>, std::vector<char>>();
+ test<MinSequenceContainer<int>, MinSequenceContainer<char>>();
+ test<std::vector<int, min_allocator<int>>, std::vector<char, min_allocator<char>>>();
+
+ return 0;
+}
diff --git a/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.iterators/iterator_concept_conformance.compile.pass.cpp b/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.iterators/iterator_concept_conformance.compile.pass.cpp
new file mode 100644
index 0000000000000..ce578e4def92b
--- /dev/null
+++ b/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.iterators/iterator_concept_conformance.compile.pass.cpp
@@ -0,0 +1,84 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+// UNSUPPORTED: c++03, c++11, c++14, c++17, c++20
+
+// <flat_map>
+
+// class flat_multimap
+
+// iterator, const_iterator, reverse_iterator, const_reverse_iterator
+
+#include <flat_map>
+#include <deque>
+#include <functional>
+#include <iterator>
+#include <string>
+#include <vector>
+#include <type_traits>
+
+#include "MinSequenceContainer.h"
+#include "test_macros.h"
+#include "min_allocator.h"
+
+template <class KeyContainer, class ValueContainer>
+void test() {
+ using Key = typename KeyContainer::value_type;
+ using Value = typename ValueContainer::value_type;
+ using C = std::flat_multimap<Key, Value, std::less<Key>, KeyContainer, ValueContainer>;
+ using I = C::iterator;
+ using CI = C::const_iterator;
+ using RI = C::reverse_iterator;
+ using CRI = C::const_reverse_iterator;
+ static_assert(std::random_access_iterator<I>);
+ static_assert(std::random_access_iterator<CI>);
+ static_assert(std::random_access_iterator<RI>);
+ static_assert(std::random_access_iterator<CRI>);
+ static_assert(!std::contiguous_iterator<I>);
+ static_assert(!std::contiguous_iterator<CI>);
+ static_assert(!std::contiguous_iterator<RI>);
+ static_assert(!std::contiguous_iterator<CRI>);
+ static_assert(!std::indirectly_writable<I, std::pair<int, char>>);
+ static_assert(!std::indirectly_writable<CI, std::pair<int, char>>);
+ static_assert(!std::indirectly_writable<RI, std::pair<int, char>>);
+ static_assert(!std::indirectly_writable<CRI, std::pair<int, char>>);
+ static_assert(std::sentinel_for<I, I>);
+ static_assert(std::sentinel_for<I, CI>);
+ static_assert(!std::sentinel_for<I, RI>);
+ static_assert(!std::sentinel_for<I, CRI>);
+ static_assert(std::sentinel_for<CI, I>);
+ static_assert(std::sentinel_for<CI, CI>);
+ static_assert(!std::sentinel_for<CI, RI>);
+ static_assert(!std::sentinel_for<CI, CRI>);
+ static_assert(!std::sentinel_for<RI, I>);
+ static_assert(!std::sentinel_for<RI, CI>);
+ static_assert(std::sentinel_for<RI, RI>);
+ static_assert(std::sentinel_for<RI, CRI>);
+ static_assert(!std::sentinel_for<CRI, I>);
+ static_assert(!std::sentinel_for<CRI, CI>);
+ static_assert(std::sentinel_for<CRI, RI>);
+ static_assert(std::sentinel_for<CRI, CRI>);
+ static_assert(std::indirectly_movable_storable<I, std::pair<int, char>*>);
+ static_assert(std::indirectly_movable_storable<CI, std::pair<int, char>*>);
+ static_assert(std::indirectly_movable_storable<RI, std::pair<int, char>*>);
+ static_assert(std::indirectly_movable_storable<CRI, std::pair<int, char>*>);
+
+#ifdef _LIBCPP_VERSION
+ static_assert(std::is_same_v<typename std::iterator_traits<I>::iterator_category, std::random_access_iterator_tag>);
+ static_assert(std::is_same_v<typename std::iterator_traits<CI>::iterator_category, std::random_access_iterator_tag>);
+ static_assert(std::is_same_v<typename std::iterator_traits<RI>::iterator_category, std::random_access_iterator_tag>);
+ static_assert(std::is_same_v<typename std::iterator_traits<CRI>::iterator_category, std::random_access_iterator_tag>);
+#endif
+}
+
+void test() {
+ test<std::vector<int>, std::vector<char>>();
+ test<std::deque<int>, std::vector<char>>();
+ test<MinSequenceContainer<int>, MinSequenceContainer<char>>();
+ test<std::vector<int, min_allocator<int>>, std::vector<char, min_allocator<char>>>();
+}
diff --git a/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.iterators/range_concept_conformance.compile.pass.cpp b/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.iterators/range_concept_conformance.compile.pass.cpp
new file mode 100644
index 0000000000000..979c0b090fd66
--- /dev/null
+++ b/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.iterators/range_concept_conformance.compile.pass.cpp
@@ -0,0 +1,55 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+// UNSUPPORTED: c++03, c++11, c++14, c++17, c++20
+
+#include <concepts>
+#include <deque>
+#include <flat_map>
+#include <functional>
+#include <ranges>
+#include <string>
+#include <vector>
+#include "MinSequenceContainer.h"
+#include "min_allocator.h"
+
+template <class KeyContainer, class ValueContainer>
+void test() {
+ {
+ using Key = typename KeyContainer::value_type;
+ using Value = typename ValueContainer::value_type;
+ using C = std::flat_multimap<Key, Value, std::less<Key>, KeyContainer, ValueContainer>;
+
+ static_assert(std::same_as<std::ranges::iterator_t<C>, typename C::iterator>);
+ static_assert(std::ranges::random_access_range<C>);
+ static_assert(!std::ranges::contiguous_range<C>);
+ static_assert(std::ranges::common_range<C>);
+ static_assert(std::ranges::input_range<C>);
+ static_assert(!std::ranges::view<C>);
+ static_assert(std::ranges::sized_range<C>);
+ static_assert(!std::ranges::borrowed_range<C>);
+ static_assert(std::ranges::viewable_range<C>);
+
+ static_assert(std::same_as<std::ranges::iterator_t<const C>, typename C::const_iterator>);
+ static_assert(std::ranges::random_access_range<const C>);
+ static_assert(!std::ranges::contiguous_range<const C>);
+ static_assert(std::ranges::common_range<const C>);
+ static_assert(std::ranges::input_range<const C>);
+ static_assert(!std::ranges::view<const C>);
+ static_assert(std::ranges::sized_range<const C>);
+ static_assert(!std::ranges::borrowed_range<const C>);
+ static_assert(!std::ranges::viewable_range<const C>);
+ }
+}
+
+void test() {
+ test<std::vector<int>, std::vector<char>>();
+ test<std::deque<int>, std::vector<char>>();
+ test<MinSequenceContainer<int>, MinSequenceContainer<char>>();
+ test<std::vector<int, min_allocator<int>>, std::vector<char, min_allocator<char>>>();
+}
diff --git a/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.iterators/reverse_iterator.pass.cpp b/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.iterators/reverse_iterator.pass.cpp
new file mode 100644
index 0000000000000..8c1e5451f703f
--- /dev/null
+++ b/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.iterators/reverse_iterator.pass.cpp
@@ -0,0 +1,92 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+// UNSUPPORTED: c++03, c++11, c++14, c++17, c++20
+
+// <flat_map>
+
+// class flat_multimap
+
+// reverse_iterator rbegin() noexcept;
+// const_reverse_iterator rbegin() const noexcept;
+// reverse_iterator rend() noexcept;
+// const_reverse_iterator rend() const noexcept;
+//
+// const_reverse_iterator crbegin() const noexcept;
+// const_reverse_iterator crend() const noexcept;
+
+#include <cassert>
+#include <cstddef>
+#include <deque>
+#include <flat_map>
+#include <functional>
+#include <vector>
+
+#include <iterator>
+
+#include "test_macros.h"
+#include <iostream>
+
+int main(int, char**) {
+ {
+ using M = std::flat_multimap<int, char, std::less<int>, std::deque<int>, std::deque<char>>;
+ M m = {{1, 'a'}, {1, 'b'}, {2, 'c'}, {2, 'd'}, {3, 'e'}, {3, 'f'}, {4, 'g'}, {4, 'h'}};
+ const M& cm = m;
+ ASSERT_SAME_TYPE(decltype(m.rbegin()), M::reverse_iterator);
+ ASSERT_SAME_TYPE(decltype(m.crbegin()), M::const_reverse_iterator);
+ ASSERT_SAME_TYPE(decltype(cm.rbegin()), M::const_reverse_iterator);
+ ASSERT_SAME_TYPE(decltype(m.rend()), M::reverse_iterator);
+ ASSERT_SAME_TYPE(decltype(m.crend()), M::const_reverse_iterator);
+ ASSERT_SAME_TYPE(decltype(cm.rend()), M::const_reverse_iterator);
+ static_assert(noexcept(m.rbegin()));
+ static_assert(noexcept(cm.rbegin()));
+ static_assert(noexcept(m.crbegin()));
+ static_assert(noexcept(m.rend()));
+ static_assert(noexcept(cm.rend()));
+ static_assert(noexcept(m.crend()));
+ assert(m.size() == 8);
+ assert(std::distance(m.rbegin(), m.rend()) == 8);
+ assert(std::distance(cm.rbegin(), cm.rend()) == 8);
+ assert(std::distance(m.crbegin(), m.crend()) == 8);
+ assert(std::distance(cm.crbegin(), cm.crend()) == 8);
+ M::reverse_iterator i; // default-construct
+ ASSERT_SAME_TYPE(decltype(i->first), const int&);
+ ASSERT_SAME_TYPE(decltype(i->second), char&);
+ i = m.rbegin(); // move-assignment
+ M::const_reverse_iterator k = i; // converting constructor
+ assert(i == k); // comparison
+ for (int j = 8; j >= 1; --j, ++i) { // pre-increment
+ assert(i->first == (j + 1) / 2); // operator->
+ assert(i->second == 'a' + j - 1);
+ }
+ assert(i == m.rend());
+ for (int j = 1; j <= 8; ++j) {
+ --i; // pre-decrement
+ assert((*i).first == (j + 1) / 2);
+ assert((*i).second == 'a' + j - 1);
+ }
+ assert(i == m.rbegin());
+ }
+ {
+ // N3644 testing
+ using C = std::flat_multimap<int, char>;
+ C::reverse_iterator ii1{}, ii2{};
+ C::reverse_iterator ii4 = ii1;
+ C::const_reverse_iterator cii{};
+ assert(ii1 == ii2);
+ assert(ii1 == ii4);
+ assert(!(ii1 != ii2));
+
+ assert((ii1 == cii));
+ assert((cii == ii1));
+ assert(!(ii1 != cii));
+ assert(!(cii != ii1));
+ }
+
+ return 0;
+}
diff --git a/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.modifiers/clear.pass.cpp b/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.modifiers/clear.pass.cpp
new file mode 100644
index 0000000000000..5b0788b6826fd
--- /dev/null
+++ b/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.modifiers/clear.pass.cpp
@@ -0,0 +1,64 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+// UNSUPPORTED: c++03, c++11, c++14, c++17, c++20
+
+// <flat_map>
+
+// class flat_multimap
+
+// void clear() noexcept;
+
+#include <cassert>
+#include <deque>
+#include <flat_map>
+#include <functional>
+#include <vector>
+
+#include "MinSequenceContainer.h"
+#include "../helpers.h"
+#include "test_macros.h"
+#include "min_allocator.h"
+
+// test noexcept
+
+template <class T>
+concept NoExceptClear = requires(T t) {
+ { t.clear() } noexcept;
+};
+
+static_assert(NoExceptClear<std::flat_multimap<int, int>>);
+#ifndef TEST_HAS_NO_EXCEPTIONS
+static_assert(
+ NoExceptClear<std::flat_multimap<int, int, std::less<int>, ThrowOnMoveContainer<int>, ThrowOnMoveContainer<int>>>);
+#endif
+
+template <class KeyContainer, class ValueContainer>
+void test() {
+ using Key = typename KeyContainer::value_type;
+ using Value = typename ValueContainer::value_type;
+ using M = std::flat_multimap<Key, Value, std::less<Key>, KeyContainer, ValueContainer>;
+
+ M m = {{5, 2}, {2, 1}, {2, 3}, {2, 1}, {5, 0}};
+ assert(m.size() == 5);
+ ASSERT_NOEXCEPT(m.clear());
+ ASSERT_SAME_TYPE(decltype(m.clear()), void);
+ m.clear();
+ assert(m.size() == 0);
+}
+
+int main(int, char**) {
+ test<std::vector<int>, std::vector<int>>();
+ test<std::vector<int>, std::vector<double>>();
+ test<std::deque<int>, std::vector<double>>();
+ test<MinSequenceContainer<int>, MinSequenceContainer<double>>();
+ test<std::vector<int, min_allocator<int>>, std::vector<double, min_allocator<double>>>();
+ test<std::vector<int, min_allocator<int>>, std::vector<int, min_allocator<int>>>();
+
+ return 0;
+}
diff --git a/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.modifiers/emplace.pass.cpp b/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.modifiers/emplace.pass.cpp
new file mode 100644
index 0000000000000..9ef0c26e54ba3
--- /dev/null
+++ b/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.modifiers/emplace.pass.cpp
@@ -0,0 +1,158 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+// UNSUPPORTED: c++03, c++11, c++14, c++17, c++20
+
+// <flat_map>
+
+// class flat_multimap
+
+// template <class... Args>
+// iterator emplace(Args&&... args);
+
+#include <flat_map>
+#include <cassert>
+#include <deque>
+#include <tuple>
+#include <functional>
+#include <vector>
+
+#include "MinSequenceContainer.h"
+#include "../helpers.h"
+#include "test_macros.h"
+#include "../../../Emplaceable.h"
+#include "DefaultOnly.h"
+#include "min_allocator.h"
+
+// Constraints: is_constructible_v<pair<key_type, mapped_type>, Args...> is true.
+template <class M, class... Args>
+concept CanEmplace = requires(M m, Args&&... args) { m.emplace(std::forward<Args>(args)...); };
+
+using Map = std::flat_multimap<Emplaceable, Emplaceable>;
+static_assert(CanEmplace<Map>);
+static_assert(CanEmplace<Map, Emplaceable, Emplaceable>);
+static_assert(CanEmplace<Map, std::piecewise_construct_t, std::tuple<int, double>, std::tuple<int, double>>);
+static_assert(!CanEmplace<Map, Emplaceable>);
+static_assert(!CanEmplace<Map, int, double>);
+
+template <class KeyContainer, class ValueContainer>
+void test() {
+ using Key = typename KeyContainer::value_type;
+ using Value = typename ValueContainer::value_type;
+ using M = std::flat_multimap<Key, Value, std::less<Key>, KeyContainer, ValueContainer>;
+ using R = typename M::iterator;
+
+ {
+ // was empty
+ M m;
+ std::same_as<R> decltype(auto) r = m.emplace(typename M::value_type(2, 3.5));
+ assert(r == m.begin());
+ assert(m.size() == 1);
+ assert(r->first == 2);
+ assert(r->second == 3.5);
+ }
+ {
+ // key does not exist and inserted at the begin
+ M m = {{3, 4.0}, {3, 3.0}, {3, 1.0}, {7, 0.0}};
+ std::same_as<R> decltype(auto) r = m.emplace(typename M::value_type(2, 2.0));
+ assert(r == m.begin());
+ assert(m.size() == 5);
+ assert(r->first == 2);
+ assert(r->second == 2.0);
+ }
+ {
+ // key does not exist and inserted in the middle
+ M m = {{1, 4.0}, {1, 3.0}, {3, 1.0}, {4, 0.0}};
+ std::same_as<R> decltype(auto) r = m.emplace(typename M::value_type(2, 2.0));
+ assert(r == m.begin() + 2);
+ assert(m.size() == 5);
+ assert(r->first == 2);
+ assert(r->second == 2.0);
+ }
+ {
+ // key does not exist and inserted at the end
+ M m = {{1, 4.0}, {1, 3.0}};
+ std::same_as<R> decltype(auto) r = m.emplace(typename M::value_type(2, 2.0));
+ assert(r == m.begin() + 2);
+ assert(m.size() == 3);
+ assert(r->first == 2);
+ assert(r->second == 2.0);
+ }
+ {
+ // key already exists and original at the begin
+ M m = {{2, 4.0}, {2, 3.0}, {5, 1.0}, {6, 0.0}};
+ std::same_as<R> decltype(auto) r = m.emplace(typename M::value_type(2, 2.0));
+ assert(r == m.begin() + 2);
+ assert(m.size() == 5);
+ assert(r->first == 2);
+ assert(r->second == 2.0);
+ }
+ {
+ // key already exists and original in the middle
+ M m = {{0, 4.0}, {2, 3.0}, {2, 1.0}, {4, 0.0}};
+ std::same_as<R> decltype(auto) r = m.emplace(typename M::value_type(2, 2.0));
+ assert(r == m.begin() + 3);
+ assert(m.size() == 5);
+ assert(r->first == 2);
+ assert(r->second == 2.0);
+ }
+ {
+ // key already exists and original at the end
+ M m = {{0, 4.0}, {1, 3.0}, {2, 1.0}};
+ std::same_as<R> decltype(auto) r = m.emplace(typename M::value_type(2, 2.0));
+ assert(r == m.begin() + 3);
+ assert(m.size() == 4);
+ assert(r->first == 2);
+ assert(r->second == 2.0);
+ }
+}
+
+template <class KeyContainer, class ValueContainer>
+void test_emplaceable() {
+ using M = std::flat_multimap<int, Emplaceable, std::less<int>, KeyContainer, ValueContainer>;
+ using R = typename M::iterator;
+
+ M m;
+ std::same_as<R> decltype(auto) r =
+ m.emplace(std::piecewise_construct, std::forward_as_tuple(2), std::forward_as_tuple());
+ assert(r == m.begin());
+ assert(m.size() == 1);
+ assert(m.begin()->first == 2);
+ assert(m.begin()->second == Emplaceable());
+ r = m.emplace(std::piecewise_construct, std::forward_as_tuple(1), std::forward_as_tuple(2, 3.5));
+ assert(r == m.begin());
+ assert(m.size() == 2);
+ assert(m.begin()->first == 1);
+ assert(m.begin()->second == Emplaceable(2, 3.5));
+ r = m.emplace(std::piecewise_construct, std::forward_as_tuple(1), std::forward_as_tuple(2, 3.5));
+ assert(r == m.begin() + 1);
+ assert(m.size() == 3);
+ assert(m.begin()->first == 1);
+ assert(m.begin()->second == Emplaceable(2, 3.5));
+}
+
+int main(int, char**) {
+ test<std::vector<int>, std::vector<double>>();
+ test<std::deque<int>, std::vector<double>>();
+ test<MinSequenceContainer<int>, MinSequenceContainer<double>>();
+ test<std::vector<int, min_allocator<int>>, std::vector<double, min_allocator<double>>>();
+
+ test_emplaceable<std::vector<int>, std::vector<Emplaceable>>();
+ test_emplaceable<std::deque<int>, std::vector<Emplaceable>>();
+ test_emplaceable<MinSequenceContainer<int>, MinSequenceContainer<Emplaceable>>();
+ test_emplaceable<std::vector<int, min_allocator<int>>, std::vector<Emplaceable, min_allocator<Emplaceable>>>();
+
+ {
+ auto emplace_func = [](auto& m, auto key_arg, auto value_arg) {
+ m.emplace(std::piecewise_construct, std::tuple(key_arg), std::tuple(value_arg));
+ };
+ test_emplace_exception_guarantee(emplace_func);
+ }
+
+ return 0;
+}
diff --git a/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.modifiers/emplace_hint.pass.cpp b/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.modifiers/emplace_hint.pass.cpp
new file mode 100644
index 0000000000000..588d27ea54f4d
--- /dev/null
+++ b/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.modifiers/emplace_hint.pass.cpp
@@ -0,0 +1,228 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+// UNSUPPORTED: c++03, c++11, c++14, c++17, c++20
+
+// <flat_map>
+
+// class flat_multimap
+
+// template <class... Args>
+// iterator emplace_hint(const_iterator position, Args&&... args);
+
+#include <flat_map>
+#include <cassert>
+#include <deque>
+#include <functional>
+#include <vector>
+
+#include "MinSequenceContainer.h"
+#include "test_macros.h"
+#include "../../../Emplaceable.h"
+#include "DefaultOnly.h"
+#include "min_allocator.h"
+#include "../helpers.h"
+
+#if defined(_LIBCPP_VERSION)
+// spec only specifies `emplace(Args&&...)` is_constructible_v<pair<key_type, mapped_type>, Args...> is true.
+// nothing mentioned for emplace_hint
+template <class M, class... Args>
+concept CanEmplaceHint =
+ requires(M m, typename M::const_iterator i, Args&&... args) { m.emplace_hint(i, std::forward<Args>(args)...); };
+
+using Map = std::flat_multimap<Emplaceable, Emplaceable>;
+static_assert(CanEmplaceHint<Map>);
+static_assert(CanEmplaceHint<Map, Emplaceable, Emplaceable>);
+static_assert(CanEmplaceHint<Map, std::piecewise_construct_t, std::tuple<int, double>, std::tuple<int, double>>);
+static_assert(!CanEmplaceHint<Map, Emplaceable>);
+static_assert(!CanEmplaceHint<Map, int, double>);
+#endif
+
+template <class KeyContainer, class ValueContainer>
+void test() {
+ using Key = typename KeyContainer::value_type;
+ using Value = typename ValueContainer::value_type;
+ using M = std::flat_multimap<Key, Value, std::less<Key>, KeyContainer, ValueContainer>;
+ using R = M::iterator;
+ {
+ // was empty
+ M m;
+ std::same_as<R> decltype(auto) r = m.emplace_hint(m.end(), typename M::value_type(2, 3.5));
+ assert(r == m.begin());
+ assert(m.size() == 1);
+ assert(m.begin()->first == 2);
+ assert(m.begin()->second == 3.5);
+ }
+ {
+ // hint correct and no duplicates
+ M m = {{0, 0.0}, {1, 1.0}, {3, 3.0}};
+ auto it = m.begin() + 2;
+ std::same_as<R> decltype(auto) r = m.emplace_hint(it, typename M::value_type(2, 2.0));
+ assert(r == m.begin() + 2);
+ assert(m.size() == 4);
+ assert(r->first == 2);
+ assert(r->second == 2.0);
+ }
+ {
+ // hint correct and at the begin
+ M m = {{3, 3.0}, {4, 4.0}};
+ auto it = m.begin();
+ std::same_as<R> decltype(auto) r = m.emplace_hint(it, typename M::value_type(2, 2.0));
+ assert(r == m.begin());
+ assert(m.size() == 3);
+ assert(r->first == 2);
+ assert(r->second == 2.0);
+ }
+ {
+ // hint correct and at the end
+ M m = {{0, 0.0}, {1, 1.0}};
+ auto it = m.end();
+ std::same_as<R> decltype(auto) r = m.emplace_hint(it, typename M::value_type(2, 2.0));
+ assert(r == m.begin() + 2);
+ assert(m.size() == 3);
+ assert(r->first == 2);
+ assert(r->second == 2.0);
+ }
+ {
+ // hint correct and at first duplicate
+ M m = {{0, 0.0}, {1, 1.0}, {2, 1.9}, {2, 2.1}, {3, 3.0}};
+ auto it = m.begin() + 2;
+ std::same_as<R> decltype(auto) r = m.emplace_hint(it, typename M::value_type(2, 2.0));
+ assert(r == m.begin() + 2);
+ assert(m.size() == 6);
+ assert(r->first == 2);
+ assert(r->second == 2.0);
+ assert(std::next(r)->first == 2);
+ assert(std::next(r)->second == 1.9);
+ }
+ {
+ // hint correct and in-between duplicates
+ M m = {{0, 0.0}, {1, 1.0}, {2, 1.8}, {2, 1.9}, {2, 2.1}, {3, 3.0}};
+ auto it = m.begin() + 4;
+ std::same_as<R> decltype(auto) r = m.emplace_hint(it, typename M::value_type(2, 2.0));
+ assert(r == m.begin() + 4);
+ assert(m.size() == 7);
+ assert(r->first == 2);
+ assert(r->second == 2.0);
+ assert(std::next(r)->first == 2);
+ assert(std::next(r)->second == 2.1);
+ }
+ {
+ // hint correct and after duplicates
+ M m = {{0, 0.0}, {1, 1.0}, {2, 1.8}, {2, 1.9}, {2, 2.1}, {3, 3.0}};
+ auto it = m.begin() + 5;
+ std::same_as<R> decltype(auto) r = m.emplace_hint(it, typename M::value_type(2, 2.0));
+ assert(r == m.begin() + 5);
+ assert(m.size() == 7);
+ assert(r->first == 2);
+ assert(r->second == 2.0);
+ assert(std::next(r)->first == 3);
+ assert(std::next(r)->second == 3.0);
+ }
+ {
+ // hint incorrect and no duplicates
+ M m = {{0, 0.0}, {1, 1.0}, {3, 3.0}};
+ auto it = m.begin() + 1;
+ std::same_as<R> decltype(auto) r = m.emplace_hint(it, typename M::value_type(2, 2.0));
+ assert(r == m.begin() + 2);
+ assert(m.size() == 4);
+ assert(r->first == 2);
+ assert(r->second == 2.0);
+ }
+ {
+ // hint incorrect and at the begin
+ M m = {{0, 0.0}, {1, 1.0}};
+ auto it = m.begin();
+ std::same_as<R> decltype(auto) r = m.emplace_hint(it, typename M::value_type(2, 2.0));
+ assert(r == m.begin() + 2);
+ assert(m.size() == 3);
+ assert(r->first == 2);
+ assert(r->second == 2.0);
+ }
+ {
+ // hint incorrect and at the end
+ M m = {{3, 3.0}, {4, 4.0}};
+ auto it = m.end();
+ std::same_as<R> decltype(auto) r = m.emplace_hint(it, typename M::value_type(2, 2.0));
+ assert(r == m.begin());
+ assert(m.size() == 3);
+ assert(r->first == 2);
+ assert(r->second == 2.0);
+ }
+ {
+ // hint incorrect and before the first duplicate
+ M m = {{0, 0.0}, {1, 1.0}, {2, 1.8}, {2, 1.9}, {2, 2.1}, {3, 3.0}};
+ auto it = m.begin();
+ std::same_as<R> decltype(auto) r = m.emplace_hint(it, typename M::value_type(2, 2.0));
+ // the result is as left as possible
+ assert(r == m.begin() + 2);
+ assert(m.size() == 7);
+ assert(r->first == 2);
+ assert(r->second == 2.0);
+ assert(std::next(r)->first == 2);
+ assert(std::next(r)->second == 1.8);
+ }
+ {
+ // hint incorrect and after the last duplicate
+ M m = {{0, 0.0}, {1, 1.0}, {2, 1.8}, {2, 1.9}, {2, 2.1}, {3, 3.0}, {4, 4.0}};
+ auto it = m.begin() + 6;
+ std::same_as<R> decltype(auto) r = m.emplace_hint(it, typename M::value_type(2, 2.0));
+ // the result is as right as possible
+ assert(r == m.begin() + 5);
+ assert(m.size() == 8);
+ assert(r->first == 2);
+ assert(r->second == 2.0);
+ assert(std::next(r)->first == 3);
+ assert(std::next(r)->second == 3.0);
+ }
+}
+
+template <class KeyContainer, class ValueContainer>
+void test_emplaceable() {
+ using M = std::flat_multimap<int, Emplaceable, std::less<int>, KeyContainer, ValueContainer>;
+ using R = M::iterator;
+
+ M m;
+ ASSERT_SAME_TYPE(decltype(m.emplace_hint(m.cbegin())), R);
+ R r = m.emplace_hint(m.end(), std::piecewise_construct, std::forward_as_tuple(2), std::forward_as_tuple());
+ assert(r == m.begin());
+ assert(m.size() == 1);
+ assert(r->first == 2);
+ assert(r->second == Emplaceable());
+ r = m.emplace_hint(m.end(), std::piecewise_construct, std::forward_as_tuple(1), std::forward_as_tuple(2, 3.5));
+ assert(r == m.begin());
+ assert(m.size() == 2);
+ assert(r->first == 1);
+ assert(r->second == Emplaceable(2, 3.5));
+ r = m.emplace_hint(m.end(), std::piecewise_construct, std::forward_as_tuple(1), std::forward_as_tuple(2, 3.6));
+ assert(r == m.begin() + 1);
+ assert(m.size() == 3);
+ assert(r->first == 1);
+ assert(r->second == Emplaceable(2, 3.6));
+}
+
+int main(int, char**) {
+ test<std::vector<int>, std::vector<double>>();
+ test<std::deque<int>, std::vector<double>>();
+ test<MinSequenceContainer<int>, MinSequenceContainer<double>>();
+ test<std::vector<int, min_allocator<int>>, std::vector<double, min_allocator<double>>>();
+
+ test_emplaceable<std::vector<int>, std::vector<Emplaceable>>();
+ test_emplaceable<std::deque<int>, std::vector<Emplaceable>>();
+ test_emplaceable<MinSequenceContainer<int>, MinSequenceContainer<Emplaceable>>();
+ test_emplaceable<std::vector<int, min_allocator<int>>, std::vector<Emplaceable, min_allocator<Emplaceable>>>();
+
+ {
+ auto emplace_func = [](auto& m, auto key_arg, auto value_arg) {
+ m.emplace_hint(m.begin(), std::piecewise_construct, std::tuple(key_arg), std::tuple(value_arg));
+ };
+ test_emplace_exception_guarantee(emplace_func);
+ }
+
+ return 0;
+}
diff --git a/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.modifiers/erase_iter.pass.cpp b/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.modifiers/erase_iter.pass.cpp
new file mode 100644
index 0000000000000..78040be2e043d
--- /dev/null
+++ b/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.modifiers/erase_iter.pass.cpp
@@ -0,0 +1,127 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+// UNSUPPORTED: c++03, c++11, c++14, c++17, c++20
+
+// <flat_map>
+
+// class flat_multimap
+
+// iterator erase(iterator position);
+// iterator erase(const_iterator position);
+
+#include <compare>
+#include <concepts>
+#include <deque>
+#include <flat_map>
+#include <functional>
+#include <utility>
+#include <vector>
+
+#include "MinSequenceContainer.h"
+#include "../helpers.h"
+#include "test_macros.h"
+#include "min_allocator.h"
+
+template <class KeyContainer, class ValueContainer>
+void test() {
+ using Key = typename KeyContainer::value_type;
+ using Value = typename ValueContainer::value_type;
+ using M = std::flat_multimap<Key, Value, std::less<Key>, KeyContainer, ValueContainer>;
+ using P = std::pair<Key, Value>;
+ using I = M::iterator;
+
+ P ar[] = {
+ P(1, 1.5),
+ P(2, 2.5),
+ P(2, 2.6),
+ P(3, 3.5),
+ P(4, 4.5),
+ P(4, 4.5),
+ P(4, 4.7),
+ P(5, 5.5),
+ P(6, 6.5),
+ P(7, 7.5),
+ P(8, 8.5),
+ };
+ M m(ar, ar + sizeof(ar) / sizeof(ar[0]));
+ assert(m.size() == 11);
+ std::same_as<I> decltype(auto) i1 = m.erase(std::next(m.cbegin(), 2));
+ assert(m.size() == 10);
+ assert(i1 == std::next(m.begin(), 2));
+ assert(std::ranges::equal(
+ m,
+ std::vector<P>{
+ {1, 1.5}, {2, 2.5}, {3, 3.5}, {4, 4.5}, {4, 4.5}, {4, 4.7}, {5, 5.5}, {6, 6.5}, {7, 7.5}, {8, 8.5}}));
+
+ std::same_as<I> decltype(auto) i2 = m.erase(std::next(m.begin(), 0));
+ assert(m.size() == 9);
+ assert(i2 == m.begin());
+ assert(std::ranges::equal(
+ m, std::vector<P>{{2, 2.5}, {3, 3.5}, {4, 4.5}, {4, 4.5}, {4, 4.7}, {5, 5.5}, {6, 6.5}, {7, 7.5}, {8, 8.5}}));
+
+ std::same_as<I> decltype(auto) i3 = m.erase(std::next(m.cbegin(), 8));
+ assert(m.size() == 8);
+ assert(i3 == m.end());
+ assert(std::ranges::equal(
+ m, std::vector<P>{{2, 2.5}, {3, 3.5}, {4, 4.5}, {4, 4.5}, {4, 4.7}, {5, 5.5}, {6, 6.5}, {7, 7.5}}));
+
+ std::same_as<I> decltype(auto) i4 = m.erase(std::next(m.begin(), 1));
+ assert(m.size() == 7);
+ assert(i4 == std::next(m.begin()));
+ assert(std::ranges::equal(m, std::vector<P>{{2, 2.5}, {4, 4.5}, {4, 4.5}, {4, 4.7}, {5, 5.5}, {6, 6.5}, {7, 7.5}}));
+
+ std::same_as<I> decltype(auto) i5 = m.erase(std::next(m.cbegin(), 2));
+ assert(m.size() == 6);
+ assert(i5 == std::next(m.begin(), 2));
+ assert(std::ranges::equal(m, std::vector<P>{{2, 2.5}, {4, 4.5}, {4, 4.7}, {5, 5.5}, {6, 6.5}, {7, 7.5}}));
+
+ std::same_as<I> decltype(auto) i6 = m.erase(std::next(m.begin(), 2));
+ assert(m.size() == 5);
+ assert(i6 == std::next(m.begin(), 2));
+ assert(std::ranges::equal(m, std::vector<P>{{2, 2.5}, {4, 4.5}, {5, 5.5}, {6, 6.5}, {7, 7.5}}));
+
+ std::same_as<I> decltype(auto) i7 = m.erase(std::next(m.cbegin(), 0));
+ assert(m.size() == 4);
+ assert(i7 == std::next(m.begin(), 0));
+ assert(std::ranges::equal(m, std::vector<P>{{4, 4.5}, {5, 5.5}, {6, 6.5}, {7, 7.5}}));
+
+ std::same_as<I> decltype(auto) i8 = m.erase(std::next(m.cbegin(), 2));
+ assert(m.size() == 3);
+ assert(i8 == std::next(m.begin(), 2));
+ assert(std::ranges::equal(m, std::vector<P>{{4, 4.5}, {5, 5.5}, {7, 7.5}}));
+
+ std::same_as<I> decltype(auto) i9 = m.erase(std::next(m.cbegin(), 2));
+ assert(m.size() == 2);
+ assert(i9 == std::next(m.begin(), 2));
+ assert(std::ranges::equal(m, std::vector<P>{{4, 4.5}, {5, 5.5}}));
+
+ std::same_as<I> decltype(auto) i10 = m.erase(m.cbegin());
+ assert(m.size() == 1);
+ assert(i10 == m.cbegin());
+ assert(std::ranges::equal(m, std::vector<P>{{5, 5.5}}));
+
+ std::same_as<I> decltype(auto) i11 = m.erase(m.begin());
+ assert(m.size() == 0);
+ assert(i11 == m.begin());
+ assert(i11 == m.end());
+}
+
+int main(int, char**) {
+ test<std::vector<int>, std::vector<double>>();
+ test<std::deque<int>, std::vector<double>>();
+ test<MinSequenceContainer<int>, MinSequenceContainer<double>>();
+ test<std::vector<int, min_allocator<int>>, std::vector<double, min_allocator<double>>>();
+
+ {
+ auto erase_function = [](auto& m, auto) { m.erase(m.begin() + 2); };
+ test_erase_exception_guarantee(erase_function);
+ }
+
+ return 0;
+}
diff --git a/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.modifiers/erase_iter_iter.pass.cpp b/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.modifiers/erase_iter_iter.pass.cpp
new file mode 100644
index 0000000000000..103f38c1c5d4a
--- /dev/null
+++ b/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.modifiers/erase_iter_iter.pass.cpp
@@ -0,0 +1,99 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+// UNSUPPORTED: c++03, c++11, c++14, c++17, c++20
+
+// <flat_map>
+
+// class flat_multimap
+
+// iterator erase(const_iterator first, const_iterator last);
+
+#include <compare>
+#include <concepts>
+#include <deque>
+#include <flat_map>
+#include <functional>
+#include <utility>
+#include <vector>
+
+#include "MinSequenceContainer.h"
+#include "../helpers.h"
+#include "test_macros.h"
+#include "min_allocator.h"
+
+template <class KeyContainer, class ValueContainer>
+void test() {
+ using Key = typename KeyContainer::value_type;
+ using Value = typename ValueContainer::value_type;
+ using M = std::flat_multimap<Key, Value, std::less<Key>, KeyContainer, ValueContainer>;
+ using P = std::pair<Key, Value>;
+ using I = M::iterator;
+
+ P ar[] = {
+ P(1, 1.5),
+ P(2, 2.5),
+ P(2, 2.6),
+ P(3, 3.5),
+ P(3, 3.6),
+ P(3, 3.7),
+ P(4, 4.5),
+ P(5, 5.5),
+ P(6, 6.5),
+ P(7, 7.5),
+ P(8, 8.5),
+ };
+ M m(ar, ar + sizeof(ar) / sizeof(ar[0]));
+ assert(m.size() == 11);
+ std::same_as<I> decltype(auto) i1 = m.erase(m.cbegin(), m.cbegin());
+ assert(m.size() == 11);
+ assert(i1 == m.begin());
+ assert(std::ranges::equal(
+ m,
+ std::vector<P>{
+ {1, 1.5},
+ {2, 2.5},
+ {2, 2.6},
+ {3, 3.5},
+ {3, 3.6},
+ {3, 3.7},
+ {4, 4.5},
+ {5, 5.5},
+ {6, 6.5},
+ {7, 7.5},
+ {8, 8.5}}));
+
+ std::same_as<I> decltype(auto) i2 = m.erase(m.cbegin(), std::next(m.cbegin(), 2));
+ assert(m.size() == 9);
+ assert(i2 == m.begin());
+ assert(std::ranges::equal(
+ m, std::vector<P>{{2, 2.6}, {3, 3.5}, {3, 3.6}, {3, 3.7}, {4, 4.5}, {5, 5.5}, {6, 6.5}, {7, 7.5}, {8, 8.5}}));
+
+ std::same_as<I> decltype(auto) i3 = m.erase(std::next(m.cbegin(), 2), std::next(m.cbegin(), 6));
+ assert(m.size() == 5);
+ assert(i3 == std::next(m.begin(), 2));
+ assert(std::ranges::equal(m, std::vector<P>{{2, 2.6}, {3, 3.5}, {6, 6.5}, {7, 7.5}, {8, 8.5}}));
+
+ std::same_as<I> decltype(auto) i4 = m.erase(m.cbegin(), m.cend());
+ assert(m.size() == 0);
+ assert(i4 == m.begin());
+ assert(i4 == m.end());
+}
+
+int main(int, char**) {
+ test<std::vector<int>, std::vector<double>>();
+ test<std::deque<int>, std::vector<double>>();
+ test<MinSequenceContainer<int>, MinSequenceContainer<double>>();
+ test<std::vector<int, min_allocator<int>>, std::vector<double, min_allocator<double>>>();
+
+ {
+ auto erase_function = [](auto& m, auto) { m.erase(m.begin(), m.begin() + 2); };
+ test_erase_exception_guarantee(erase_function);
+ }
+ return 0;
+}
diff --git a/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.modifiers/erase_key.pass.cpp b/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.modifiers/erase_key.pass.cpp
new file mode 100644
index 0000000000000..7944996fba1a0
--- /dev/null
+++ b/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.modifiers/erase_key.pass.cpp
@@ -0,0 +1,99 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+// UNSUPPORTED: c++03, c++11, c++14, c++17, c++20
+
+// <flat_map>
+
+// class flat_multimap
+
+// size_type erase(const key_type& k);
+
+#include <compare>
+#include <concepts>
+#include <deque>
+#include <flat_map>
+#include <functional>
+#include <utility>
+#include <vector>
+
+#include "MinSequenceContainer.h"
+#include "../helpers.h"
+#include "test_macros.h"
+#include "min_allocator.h"
+
+template <class KeyContainer, class ValueContainer, class Compare = std::less<>>
+void test() {
+ using M = std::flat_multimap<int, char, Compare, KeyContainer, ValueContainer>;
+
+ auto make = [](std::initializer_list<int> il) {
+ M m;
+ for (int i : il) {
+ m.emplace(i, i);
+ }
+ return m;
+ };
+ M m = make({1, 1, 2, 2, 2, 3, 4, 5, 5, 6, 7, 8, 8, 8, 8, 9});
+ ASSERT_SAME_TYPE(decltype(m.erase(9)), typename M::size_type);
+ auto n = m.erase(10);
+ assert(n == 0);
+ assert(m == make({1, 1, 2, 2, 2, 3, 4, 5, 5, 6, 7, 8, 8, 8, 8, 9}));
+ n = m.erase(4);
+ assert(n == 1);
+ assert(m == make({1, 1, 2, 2, 2, 3, 5, 5, 6, 7, 8, 8, 8, 8, 9}));
+ n = m.erase(1);
+ assert(n == 2);
+ assert(m == make({2, 2, 2, 3, 5, 5, 6, 7, 8, 8, 8, 8, 9}));
+ n = m.erase(8);
+ assert(n == 4);
+ assert(m == make({2, 2, 2, 3, 5, 5, 6, 7, 9}));
+ n = m.erase(3);
+ assert(n == 1);
+ assert(m == make({2, 2, 2, 5, 5, 6, 7, 9}));
+ n = m.erase(4);
+ assert(n == 0);
+ assert(m == make({2, 2, 2, 5, 5, 6, 7, 9}));
+ n = m.erase(6);
+ assert(n == 1);
+ assert(m == make({2, 2, 2, 5, 5, 7, 9}));
+ n = m.erase(7);
+ assert(n == 1);
+ assert(m == make({2, 2, 2, 5, 5, 9}));
+ n = m.erase(2);
+ assert(n == 3);
+ assert(m == make({5, 5, 9}));
+ n = m.erase(5);
+ assert(n == 2);
+ assert(m == make({9}));
+ n = m.erase(9);
+ assert(n == 1);
+ assert(m.empty());
+ n = m.erase(1);
+ assert(n == 0);
+ assert(m.empty());
+}
+
+int main(int, char**) {
+ test<std::vector<int>, std::vector<char>>();
+ test<std::vector<int>, std::vector<char>, std::greater<>>();
+ test<std::deque<int>, std::vector<char>>();
+ test<MinSequenceContainer<int>, MinSequenceContainer<char>>();
+ test<std::vector<int, min_allocator<int>>, std::vector<char, min_allocator<char>>>();
+
+ {
+ auto erase_function = [](auto& m, auto key_arg) {
+ using Map = std::decay_t<decltype(m)>;
+ using Key = typename Map::key_type;
+ const Key key{key_arg};
+ m.erase(key);
+ };
+ test_erase_exception_guarantee(erase_function);
+ }
+
+ return 0;
+}
diff --git a/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.modifiers/erase_key_transparent.pass.cpp b/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.modifiers/erase_key_transparent.pass.cpp
new file mode 100644
index 0000000000000..75a2d205b8f87
--- /dev/null
+++ b/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.modifiers/erase_key_transparent.pass.cpp
@@ -0,0 +1,161 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+// UNSUPPORTED: c++03, c++11, c++14, c++17, c++20
+
+// <flat_map>
+
+// class flat_multimap
+
+// size_type erase(K&& k);
+
+#include <compare>
+#include <concepts>
+#include <deque>
+#include <flat_map>
+#include <functional>
+#include <string>
+#include <utility>
+#include <vector>
+
+#include "MinSequenceContainer.h"
+#include "../helpers.h"
+#include "test_macros.h"
+#include "min_allocator.h"
+
+// Constraints: The qualified-id Compare::is_transparent is valid and denotes a type.
+template <class M>
+concept CanErase = requires(M m, Transparent<int> k) { m.erase(k); };
+using TransparentMap = std::flat_multimap<int, double, TransparentComparator>;
+using NonTransparentMap = std::flat_multimap<int, double, NonTransparentComparator>;
+static_assert(CanErase<TransparentMap>);
+static_assert(!CanErase<const TransparentMap>);
+static_assert(!CanErase<NonTransparentMap>);
+static_assert(!CanErase<const NonTransparentMap>);
+
+template <class Key, class It>
+struct HeterogeneousKey {
+ explicit HeterogeneousKey(Key key, It it) : key_(key), it_(it) {}
+ operator It() && { return it_; }
+ auto operator<=>(Key key) const { return key_ <=> key; }
+ friend bool operator<(const HeterogeneousKey&, const HeterogeneousKey&) {
+ assert(false);
+ return false;
+ }
+ Key key_;
+ It it_;
+};
+
+template <class KeyContainer, class ValueContainer>
+void test_simple() {
+ using Key = typename KeyContainer::value_type;
+ using Value = typename ValueContainer::value_type;
+ using M = std::flat_multimap<Key, Value, std::ranges::less, KeyContainer, ValueContainer>;
+
+ M m = {{1, 1}, {2, 2}, {2, 2}, {3, 3}, {3, 4}, {3, 5}, {4, 4}};
+ ASSERT_SAME_TYPE(decltype(m.erase(9)), typename M::size_type);
+ auto n = m.erase(3); // erase(K&&) [with K=int]
+ assert(n == 3);
+ assert((m == M{{1, 1}, {2, 2}, {2, 2}, {4, 4}}));
+ typename M::key_type lvalue = 2;
+ n = m.erase(lvalue); // erase(K&&) [with K=int&]
+ assert(n == 2);
+ assert((m == M{{1, 1}, {4, 4}}));
+ const typename M::key_type const_lvalue = 1;
+ n = m.erase(const_lvalue); // erase(const key_type&)
+ assert(n == 1);
+ assert((m == M{{4, 4}}));
+}
+
+template <class KeyContainer, class ValueContainer>
+void test_transparent_comparator() {
+ using M = std::flat_multimap<std::string, int, TransparentComparator, KeyContainer, ValueContainer>;
+ using P = std::pair<std::string, int>;
+ M m = {
+ {"alpha", 1}, {"beta", 2}, {"epsilon", 3}, {"epsilon", 4}, {"eta", 4}, {"gamma", 5}, {"gamma", 6}, {"gamma", 7}};
+ ASSERT_SAME_TYPE(decltype(m.erase(Transparent<std::string>{"abc"})), typename M::size_type);
+
+ auto n = m.erase(Transparent<std::string>{"epsilon"});
+ assert(n == 2);
+ assert(std::ranges::equal(
+ m, std::vector<P>{{"alpha", 1}, {"beta", 2}, {"eta", 4}, {"gamma", 5}, {"gamma", 6}, {"gamma", 7}}));
+
+ auto n2 = m.erase(Transparent<std::string>{"aaa"});
+ assert(n2 == 0);
+ assert(std::ranges::equal(
+ m, std::vector<P>{{"alpha", 1}, {"beta", 2}, {"eta", 4}, {"gamma", 5}, {"gamma", 6}, {"gamma", 7}}));
+
+ auto n3 = m.erase(Transparent<std::string>{"gamma"});
+ assert(n3 == 3);
+ assert(std::ranges::equal(m, std::vector<P>{{"alpha", 1}, {"beta", 2}, {"eta", 4}}));
+
+ auto n4 = m.erase(Transparent<std::string>{"alpha"});
+ assert(n4 == 1);
+ assert(std::ranges::equal(m, std::vector<P>{{"beta", 2}, {"eta", 4}}));
+
+ auto n5 = m.erase(Transparent<std::string>{"alpha"});
+ assert(n5 == 0);
+ assert(std::ranges::equal(m, std::vector<P>{{"beta", 2}, {"eta", 4}}));
+
+ auto n6 = m.erase(Transparent<std::string>{"beta"});
+ assert(n6 == 1);
+ assert(std::ranges::equal(m, std::vector<P>{{"eta", 4}}));
+
+ auto n7 = m.erase(Transparent<std::string>{"eta"});
+ assert(n7 == 1);
+ assert(std::ranges::equal(m, std::vector<P>{}));
+
+ auto n8 = m.erase(Transparent<std::string>{"eta"});
+ assert(n8 == 0);
+ assert(std::ranges::equal(m, std::vector<P>{}));
+}
+
+int main(int, char**) {
+ test_simple<std::vector<int>, std::vector<double>>();
+ test_simple<std::deque<int>, std::vector<double>>();
+ test_simple<MinSequenceContainer<int>, MinSequenceContainer<double>>();
+ test_simple<std::vector<int, min_allocator<int>>, std::vector<double, min_allocator<double>>>();
+
+ test_transparent_comparator<std::vector<std::string>, std::vector<int>>();
+ test_transparent_comparator<std::deque<std::string>, std::vector<int>>();
+ test_transparent_comparator<MinSequenceContainer<std::string>, MinSequenceContainer<int>>();
+ test_transparent_comparator<std::vector<std::string, min_allocator<std::string>>,
+ std::vector<int, min_allocator<int>>>();
+
+ {
+ // P2077's HeterogeneousKey example
+ using M = std::flat_multimap<int, int, std::less<>>;
+ M m = {{1, 1}, {2, 2}, {3, 3}, {3, 3}, {4, 4}, {5, 5}, {6, 6}, {6, 6}, {7, 7}, {8, 8}, {8, 8}};
+ auto h1 = HeterogeneousKey<int, M::iterator>(8, m.begin());
+ std::same_as<M::size_type> auto n = m.erase(h1); // lvalue is not convertible to It; erase(K&&) is the best match
+ assert(n == 2);
+ assert((m == M{{1, 1}, {2, 2}, {3, 3}, {3, 3}, {4, 4}, {5, 5}, {6, 6}, {6, 6}, {7, 7}}));
+ std::same_as<M::iterator> auto it = m.erase(std::move(h1)); // rvalue is convertible to It; erase(K&&) drops out
+ assert(it == m.begin());
+ assert((m == M{{2, 2}, {3, 3}, {3, 3}, {4, 4}, {5, 5}, {6, 6}, {6, 6}, {7, 7}}));
+ }
+ {
+ bool transparent_used = false;
+ TransparentComparator c(transparent_used);
+ std::flat_multimap<int, int, TransparentComparator> m(std::sorted_equivalent, {{1, 1}, {2, 2}, {3, 3}, {3, 3}}, c);
+ assert(!transparent_used);
+ auto n = m.erase(Transparent<int>{3});
+ assert(n == 2);
+ assert(transparent_used);
+ }
+ {
+ auto erase_transparent = [](auto& m, auto key_arg) {
+ using Map = std::decay_t<decltype(m)>;
+ using Key = typename Map::key_type;
+ m.erase(Transparent<Key>{key_arg});
+ };
+ test_erase_exception_guarantee(erase_transparent);
+ }
+
+ return 0;
+}
diff --git a/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.modifiers/extract.pass.cpp b/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.modifiers/extract.pass.cpp
new file mode 100644
index 0000000000000..f5ed4a9663a9d
--- /dev/null
+++ b/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.modifiers/extract.pass.cpp
@@ -0,0 +1,93 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+// UNSUPPORTED: c++03, c++11, c++14, c++17, c++20
+
+// <flat_map>
+
+// class flat_multimap
+
+// containers extract() &&;
+
+#include <algorithm>
+#include <concepts>
+#include <deque>
+#include <flat_map>
+#include <functional>
+#include <vector>
+
+#include "MinSequenceContainer.h"
+#include "../helpers.h"
+#include "test_macros.h"
+#include "min_allocator.h"
+
+template <class T>
+concept CanExtract = requires(T&& t) { std::forward<T>(t).extract(); };
+
+static_assert(CanExtract<std::flat_multimap<int, int>&&>);
+static_assert(!CanExtract<std::flat_multimap<int, int>&>);
+static_assert(!CanExtract<std::flat_multimap<int, int> const&>);
+static_assert(!CanExtract<std::flat_multimap<int, int> const&&>);
+
+template <class KeyContainer, class ValueContainer>
+void test() {
+ using M = std::flat_multimap<int, int, std::less<int>, KeyContainer, ValueContainer>;
+ M m = M({1, 2, 2, 2, 3, 3}, {4, 5, 6, 7, 8, 9});
+
+ std::same_as<typename M::containers> auto containers = std::move(m).extract();
+
+ auto expected_keys = {1, 2, 2, 2, 3, 3};
+ auto expected_values = {4, 5, 6, 7, 8, 9};
+ assert(std::ranges::equal(containers.keys, expected_keys));
+ assert(std::ranges::equal(containers.values, expected_values));
+ check_invariant(m);
+ LIBCPP_ASSERT(m.empty());
+ LIBCPP_ASSERT(m.keys().size() == 0);
+ LIBCPP_ASSERT(m.values().size() == 0);
+}
+
+int main(int, char**) {
+ test<std::vector<int>, std::vector<int>>();
+ test<std::deque<int>, std::vector<int>>();
+ test<MinSequenceContainer<int>, MinSequenceContainer<int>>();
+ test<std::vector<int, min_allocator<int>>, std::vector<int, min_allocator<int>>>();
+ {
+ // extracted object maintains invariant if one of underlying container does not clear after move
+ using M = std::flat_multimap<int, int, std::less<>, std::vector<int>, CopyOnlyVector<int>>;
+ M m = M({1, 2, 2, 2, 3, 3}, {1, 2, 3, 4, 5, 6});
+ std::same_as<M::containers> auto containers = std::move(m).extract();
+ assert(containers.keys.size() == 6);
+ assert(containers.values.size() == 6);
+ check_invariant(m);
+ LIBCPP_ASSERT(m.empty());
+ LIBCPP_ASSERT(m.keys().size() == 0);
+ LIBCPP_ASSERT(m.values().size() == 0);
+ }
+
+ {
+#ifndef TEST_HAS_NO_EXCEPTIONS
+ using KeyContainer = std::vector<int>;
+ using ValueContainer = ThrowOnMoveContainer<int>;
+ using M = std::flat_multimap<int, int, std::ranges::less, KeyContainer, ValueContainer>;
+
+ M m;
+ m.emplace(1, 1);
+ m.emplace(1, 1);
+ try {
+ auto c = std::move(m).extract();
+ assert(false);
+ } catch (int) {
+ check_invariant(m);
+ // In libc++, we try to erase the key after value emplacement failure.
+ // and after erasure failure, we clear the flat_multimap
+ LIBCPP_ASSERT(m.size() == 0);
+ }
+#endif
+ }
+ return 0;
+}
diff --git a/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.modifiers/insert_cv.pass.cpp b/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.modifiers/insert_cv.pass.cpp
new file mode 100644
index 0000000000000..88c173d8a6917
--- /dev/null
+++ b/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.modifiers/insert_cv.pass.cpp
@@ -0,0 +1,81 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+// UNSUPPORTED: c++03, c++11, c++14, c++17, c++20
+
+// <flat_map>
+
+// class flat_multimap
+
+// iterator insert(const value_type& v);
+
+#include <flat_map>
+#include <deque>
+#include <cassert>
+#include <functional>
+
+#include "MinSequenceContainer.h"
+#include "test_macros.h"
+#include "../helpers.h"
+#include "min_allocator.h"
+
+template <class KeyContainer, class ValueContainer>
+void test() {
+ using Key = typename KeyContainer::value_type;
+ using Value = typename ValueContainer::value_type;
+ using M = std::flat_multimap<Key, Value, std::less<Key>, KeyContainer, ValueContainer>;
+ using R = typename M::iterator;
+ using VT = typename M::value_type;
+ M m;
+
+ const VT v1(2, 2.5);
+ std::same_as<R> decltype(auto) r = m.insert(v1);
+ assert(r == m.begin());
+ assert(m.size() == 1);
+ assert(r->first == 2);
+ assert(r->second == 2.5);
+
+ const VT v2(1, 1.5);
+ r = m.insert(v2);
+ assert(r == m.begin());
+ assert(m.size() == 2);
+ assert(r->first == 1);
+ assert(r->second == 1.5);
+
+ const VT v3(3, 3.5);
+ r = m.insert(v3);
+ assert(r == m.begin() + 2);
+ assert(m.size() == 3);
+ assert(r->first == 3);
+ assert(r->second == 3.5);
+
+ const VT v4(3, 4.5);
+ r = m.insert(v4);
+ assert(r == m.begin() + 3);
+ assert(m.size() == 4);
+ assert(r->first == 3);
+ assert(r->second == 4.5);
+}
+
+int main(int, char**) {
+ test<std::vector<int>, std::vector<double>>();
+ test<std::deque<int>, std::vector<double>>();
+ test<MinSequenceContainer<int>, MinSequenceContainer<double>>();
+ test<std::vector<int, min_allocator<int>>, std::vector<double, min_allocator<double>>>();
+
+ {
+ auto insert_func = [](auto& m, auto key_arg, auto value_arg) {
+ using FlatMap = std::decay_t<decltype(m)>;
+ using value_type = typename FlatMap::value_type;
+ const value_type p(std::piecewise_construct, std::tuple(key_arg), std::tuple(value_arg));
+ m.insert(p);
+ };
+ test_emplace_exception_guarantee(insert_func);
+ }
+ return 0;
+}
diff --git a/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.modifiers/insert_initializer_list.pass.cpp b/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.modifiers/insert_initializer_list.pass.cpp
new file mode 100644
index 0000000000000..098b66cc49f18
--- /dev/null
+++ b/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.modifiers/insert_initializer_list.pass.cpp
@@ -0,0 +1,83 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+// UNSUPPORTED: c++03, c++11, c++14, c++17, c++20
+
+// <flat_map>
+
+// class flat_multimap
+
+// void insert(initializer_list<value_type> il);
+
+#include <flat_map>
+#include <cassert>
+#include <functional>
+#include <deque>
+
+#include "MinSequenceContainer.h"
+#include "../helpers.h"
+#include "test_macros.h"
+#include "min_allocator.h"
+
+template <class KeyContainer, class ValueContainer>
+void test() {
+ using Key = typename KeyContainer::value_type;
+ using Value = typename ValueContainer::value_type;
+ using M = std::flat_multimap<Key, Value, std::less<Key>, KeyContainer, ValueContainer>;
+ using V = std::pair<int, double>;
+
+ M m = {{1, 1}, {1, 1.5}, {1, 2}, {3, 1}, {3, 1.5}, {3, 2}};
+ m.insert({
+ {4, 1},
+ {4, 1.5},
+ {4, 2},
+ {1, 1},
+ {1, 1.5},
+ {1, 2},
+ {2, 1},
+ {2, 1.5},
+ {2, 2},
+ });
+ assert(m.size() == 15);
+ std::vector<V> expected = {
+ {1, 1},
+ {1, 1.5},
+ {1, 2},
+ {1, 1},
+ {1, 1.5},
+ {1, 2},
+ {2, 1},
+ {2, 1.5},
+ {2, 2},
+ {3, 1},
+ {3, 1.5},
+ {3, 2},
+ {4, 1},
+ {4, 1.5},
+ {4, 2},
+ };
+ assert(std::ranges::equal(m, expected));
+}
+
+int main(int, char**) {
+ test<std::vector<int>, std::vector<double>>();
+ test<std::deque<int>, std::vector<double>>();
+ test<MinSequenceContainer<int>, MinSequenceContainer<double>>();
+ test<std::vector<int, min_allocator<int>>, std::vector<double, min_allocator<double>>>();
+
+ {
+ auto insert_func = [](auto& m, const auto& newValues) {
+ using FlatMap = std::decay_t<decltype(m)>;
+ using value_type = typename FlatMap::value_type;
+ std::initializer_list<value_type> il = {{newValues[0].first, newValues[0].second}};
+ m.insert(il);
+ };
+ test_insert_range_exception_guarantee(insert_func);
+ }
+ return 0;
+}
diff --git a/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.modifiers/insert_iter_cv.pass.cpp b/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.modifiers/insert_iter_cv.pass.cpp
new file mode 100644
index 0000000000000..9d645043a15ca
--- /dev/null
+++ b/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.modifiers/insert_iter_cv.pass.cpp
@@ -0,0 +1,95 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+// UNSUPPORTED: c++03, c++11, c++14, c++17, c++20
+
+// <flat_map>
+
+// class flat_multimap
+
+// iterator insert(const_iterator position, const value_type& v);
+
+#include <flat_map>
+#include <cassert>
+#include <functional>
+#include <deque>
+
+#include "MinSequenceContainer.h"
+#include "test_macros.h"
+#include "../helpers.h"
+#include "min_allocator.h"
+
+template <class KeyContainer, class ValueContainer>
+void test() {
+ using Key = typename KeyContainer::value_type;
+ using Value = typename ValueContainer::value_type;
+ using M = std::flat_multimap<Key, Value, std::less<Key>, KeyContainer, ValueContainer>;
+ using R = typename M::iterator;
+ using VT = typename M::value_type;
+
+ M m;
+ const VT v1(2, 2.5);
+ std::same_as<R> decltype(auto) r = m.insert(m.end(), v1);
+ assert(r == m.begin());
+ assert(m.size() == 1);
+ assert(r->first == 2);
+ assert(r->second == 2.5);
+
+ const VT v2(1, 1.5);
+ r = m.insert(m.end(), v2);
+ assert(r == m.begin());
+ assert(m.size() == 2);
+ assert(r->first == 1);
+ assert(r->second == 1.5);
+
+ const VT v3(3, 3.5);
+ r = m.insert(m.end(), v3);
+ assert(r == std::ranges::prev(m.end()));
+ assert(m.size() == 3);
+ assert(r->first == 3);
+ assert(r->second == 3.5);
+
+ const VT v4(3, 4.5);
+ r = m.insert(m.end(), v4);
+ assert(r == std::ranges::prev(m.end()));
+ assert(m.size() == 4);
+ assert(r->first == 3);
+ assert(r->second == 4.5);
+
+ const VT v5(2, 5.5);
+ r = m.insert(m.end(), v5);
+ assert(r == m.begin() + 2);
+ assert(m.size() == 5);
+ assert(r->first == 2);
+ assert(r->second == 5.5);
+
+ const VT v6(2, 6.5);
+ r = m.insert(m.begin(), v6);
+ assert(r == m.begin() + 1);
+ assert(m.size() == 6);
+ assert(r->first == 2);
+ assert(r->second == 6.5);
+}
+
+int main(int, char**) {
+ test<std::vector<int>, std::vector<double>>();
+ test<std::deque<int>, std::vector<double>>();
+ test<MinSequenceContainer<int>, MinSequenceContainer<double>>();
+ test<std::vector<int, min_allocator<int>>, std::vector<double, min_allocator<double>>>();
+
+ {
+ auto insert_func = [](auto& m, auto key_arg, auto value_arg) {
+ using FlatMap = std::decay_t<decltype(m)>;
+ using value_type = typename FlatMap::value_type;
+ const value_type p(std::piecewise_construct, std::tuple(key_arg), std::tuple(value_arg));
+ m.insert(m.begin(), p);
+ };
+ test_emplace_exception_guarantee(insert_func);
+ }
+ return 0;
+}
diff --git a/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.modifiers/insert_iter_iter.pass.cpp b/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.modifiers/insert_iter_iter.pass.cpp
new file mode 100644
index 0000000000000..ae031bd010f76
--- /dev/null
+++ b/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.modifiers/insert_iter_iter.pass.cpp
@@ -0,0 +1,109 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+// UNSUPPORTED: c++03, c++11, c++14, c++17, c++20
+
+// <flat_map>
+
+// class flat_multimap
+
+// template <class InputIterator>
+// void insert(InputIterator first, InputIterator last);
+
+#include <flat_map>
+#include <cassert>
+#include <functional>
+#include <deque>
+
+#include "MinSequenceContainer.h"
+#include "../helpers.h"
+#include "test_macros.h"
+#include "test_iterators.h"
+#include "min_allocator.h"
+
+// test constraint InputIterator
+template <class M, class... Args>
+concept CanInsert = requires(M m, Args&&... args) { m.insert(std::forward<Args>(args)...); };
+
+using Map = std::flat_multimap<int, int>;
+using Pair = std::pair<int, int>;
+
+static_assert(CanInsert<Map, Pair*, Pair*>);
+static_assert(CanInsert<Map, cpp17_input_iterator<Pair*>, cpp17_input_iterator<Pair*>>);
+static_assert(!CanInsert<Map, int, int>);
+static_assert(!CanInsert<Map, cpp20_input_iterator<Pair*>, cpp20_input_iterator<Pair*>>);
+
+template <class KeyContainer, class ValueContainer>
+void test() {
+ using P = std::pair<int, double>;
+ using M = std::flat_multimap<int, double, std::less<int>, KeyContainer, ValueContainer>;
+
+ P ar1[] = {
+ P(2, 1),
+ P(2, 1.5),
+ P(2, 2),
+ P(1, 1),
+ P(1, 1.5),
+ P(1, 2),
+ P(3, 1),
+ P(3, 1.5),
+ P(3, 2),
+ };
+ P ar2[] = {
+ P(4, 1),
+ P(4, 1.5),
+ P(4, 2),
+ P(1, 1),
+ P(1, 1.5),
+ P(1, 2),
+ P(0, 1),
+ P(0, 1.5),
+ P(0, 2),
+ };
+
+ M m;
+ m.insert(cpp17_input_iterator<P*>(ar1), cpp17_input_iterator<P*>(ar1 + sizeof(ar1) / sizeof(ar1[0])));
+ assert(m.size() == 9);
+ std::vector<P> expected{{1, 1}, {1, 1.5}, {1, 2}, {2, 1}, {2, 1.5}, {2, 2}, {3, 1}, {3, 1.5}, {3, 2}};
+ assert(std::ranges::equal(m, expected));
+
+ m.insert(cpp17_input_iterator<P*>(ar2), cpp17_input_iterator<P*>(ar2 + sizeof(ar2) / sizeof(ar2[0])));
+ assert(m.size() == 18);
+ std::vector<P> expected2{
+ {0, 1},
+ {0, 1.5},
+ {0, 2},
+ {1, 1},
+ {1, 1.5},
+ {1, 2},
+ {1, 1},
+ {1, 1.5},
+ {1, 2},
+ {2, 1},
+ {2, 1.5},
+ {2, 2},
+ {3, 1},
+ {3, 1.5},
+ {3, 2},
+ {4, 1},
+ {4, 1.5},
+ {4, 2}};
+ assert(std::ranges::equal(m, expected2));
+}
+int main(int, char**) {
+ test<std::vector<int>, std::vector<double>>();
+ test<std::deque<int>, std::vector<double>>();
+ test<MinSequenceContainer<int>, MinSequenceContainer<double>>();
+ test<std::vector<int, min_allocator<int>>, std::vector<double, min_allocator<double>>>();
+
+ {
+ auto insert_func = [](auto& m, const auto& newValues) { m.insert(newValues.begin(), newValues.end()); };
+ test_insert_range_exception_guarantee(insert_func);
+ }
+ return 0;
+}
diff --git a/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.modifiers/insert_iter_rv.pass.cpp b/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.modifiers/insert_iter_rv.pass.cpp
new file mode 100644
index 0000000000000..61962f4873aee
--- /dev/null
+++ b/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.modifiers/insert_iter_rv.pass.cpp
@@ -0,0 +1,103 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+// UNSUPPORTED: c++03, c++11, c++14, c++17, c++20
+
+// <flat_map>
+
+// class flat_multimap
+
+// iterator insert(const_iterator position, value_type&&);
+
+#include <flat_map>
+#include <cassert>
+#include <deque>
+
+#include "MinSequenceContainer.h"
+#include "MoveOnly.h"
+#include "min_allocator.h"
+#include "../helpers.h"
+#include "test_macros.h"
+
+template <class Container, class Pair>
+void do_insert_iter_rv_test() {
+ using M = Container;
+ using P = Pair;
+ using R = typename M::iterator;
+ M m;
+ std::same_as<R> decltype(auto) r = m.insert(m.end(), P(2, 2));
+ assert(r == m.begin());
+ assert(m.size() == 1);
+ assert(r->first == 2);
+ assert(r->second == 2);
+
+ r = m.insert(m.end(), P(1, 1));
+ assert(r == m.begin());
+ assert(m.size() == 2);
+ assert(r->first == 1);
+ assert(r->second == 1);
+
+ r = m.insert(m.end(), P(3, 3));
+ assert(r == std::ranges::prev(m.end()));
+ assert(m.size() == 3);
+ assert(r->first == 3);
+ assert(r->second == 3);
+
+ r = m.insert(m.end(), P(3, 4));
+ assert(r == std::ranges::prev(m.end()));
+ assert(m.size() == 4);
+ assert(r->first == 3);
+ assert(r->second == 4);
+
+ r = m.insert(m.end(), P(2, 5));
+ assert(r == m.begin() + 2);
+ assert(m.size() == 5);
+ assert(r->first == 2);
+ assert(r->second == 5);
+
+ r = m.insert(m.begin(), P(2, 6));
+ assert(r == m.begin() + 1);
+ assert(m.size() == 6);
+ assert(r->first == 2);
+ assert(r->second == 6);
+}
+
+template <class KeyContainer, class ValueContainer>
+void test() {
+ using Key = typename KeyContainer::value_type;
+ using Value = typename ValueContainer::value_type;
+ using M = std::flat_multimap<Key, Value, std::less<Key>, KeyContainer, ValueContainer>;
+ using P = std::pair<Key, Value>;
+ using CP = std::pair<const Key, Value>;
+
+ do_insert_iter_rv_test<M, P>();
+ do_insert_iter_rv_test<M, CP>();
+}
+
+int main(int, char**) {
+ test<std::vector<int>, std::vector<double>>();
+ test<std::vector<int>, std::vector<MoveOnly>>();
+ test<std::deque<int>, std::deque<double>>();
+ test<std::deque<int>, std::deque<MoveOnly>>();
+ test<MinSequenceContainer<int>, MinSequenceContainer<double>>();
+ test<MinSequenceContainer<int>, MinSequenceContainer<MoveOnly>>();
+ test<std::vector<int, min_allocator<int>>, std::vector<double, min_allocator<double>>>();
+ test<std::vector<int, min_allocator<int>>, std::vector<MoveOnly, min_allocator<MoveOnly>>>();
+
+ {
+ auto insert_func = [](auto& m, auto key_arg, auto value_arg) {
+ using FlatMap = std::decay_t<decltype(m)>;
+ using value_type = typename FlatMap::value_type;
+ value_type p(std::piecewise_construct, std::tuple(key_arg), std::tuple(value_arg));
+ m.insert(m.begin(), std::move(p));
+ };
+ test_emplace_exception_guarantee(insert_func);
+ }
+
+ return 0;
+}
diff --git a/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.modifiers/insert_range.pass.cpp b/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.modifiers/insert_range.pass.cpp
new file mode 100644
index 0000000000000..97b8f17d1094f
--- /dev/null
+++ b/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.modifiers/insert_range.pass.cpp
@@ -0,0 +1,101 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+// UNSUPPORTED: c++03, c++11, c++14, c++17, c++20
+
+// <flat_map>
+
+// class flat_multimap
+
+// template<container-compatible-range<value_type> R>
+// void insert_range(R&& rg);
+
+#include <algorithm>
+#include <deque>
+#include <flat_map>
+#include <functional>
+#include <ranges>
+#include <vector>
+
+#include "MinSequenceContainer.h"
+#include "../helpers.h"
+#include "MoveOnly.h"
+#include "test_macros.h"
+#include "test_iterators.h"
+#include "min_allocator.h"
+
+// test constraint container-compatible-range
+template <class M, class R>
+concept CanInsertRange = requires(M m, R&& r) { m.insert_range(std::forward<R>(r)); };
+
+using Map = std::flat_multimap<int, double>;
+
+static_assert(CanInsertRange<Map, std::ranges::subrange<std::pair<int, double>*>>);
+static_assert(CanInsertRange<Map, std::ranges::subrange<std::pair<short, double>*>>);
+static_assert(!CanInsertRange<Map, std::ranges::subrange<int*>>);
+static_assert(!CanInsertRange<Map, std::ranges::subrange<double*>>);
+
+template <class KeyContainer, class ValueContainer>
+void test() {
+ using Key = typename KeyContainer::value_type;
+ using Value = typename ValueContainer::value_type;
+
+ {
+ using P = std::pair<int, int>;
+ using M = std::flat_multimap<Key, Value, std::less<Key>, KeyContainer, ValueContainer>;
+ using It = forward_iterator<const P*>;
+ M m = {{10, 1}, {8, 2}, {5, 3}, {2, 4}, {1, 5}};
+ P ar[] = {{3, 1}, {1, 2}, {4, 3}, {1, 4}, {5, 5}, {9, 6}};
+ std::ranges::subrange r = {It(ar), It(ar + 6)};
+ static_assert(std::ranges::common_range<decltype(r)>);
+ m.insert_range(r);
+ std::vector<P> expected = {{1, 5}, {1, 2}, {1, 4}, {2, 4}, {3, 1}, {4, 3}, {5, 3}, {5, 5}, {8, 2}, {9, 6}, {10, 1}};
+ assert(std::ranges::equal(m, expected));
+ }
+ {
+ using P = std::pair<int, int>;
+ using M = std::flat_multimap<Key, Value, std::greater<>, KeyContainer, ValueContainer>;
+ using It = cpp20_input_iterator<const P*>;
+ M m = {{8, 1}, {5, 2}, {3, 3}, {2, 4}};
+ P ar[] = {{3, 1}, {1, 2}, {4, 3}, {1, 4}, {5, 5}, {9, 6}};
+ std::ranges::subrange r = {It(ar), sentinel_wrapper<It>(It(ar + 6))};
+ static_assert(!std::ranges::common_range<decltype(r)>);
+ m.insert_range(r);
+ std::vector<P> expected = {{9, 6}, {8, 1}, {5, 2}, {5, 5}, {4, 3}, {3, 3}, {3, 1}, {2, 4}, {1, 2}, {1, 4}};
+ assert(std::ranges::equal(m, expected));
+ }
+}
+
+int main(int, char**) {
+ test<std::vector<int>, std::vector<int>>();
+ test<std::deque<int>, std::vector<int>>();
+ test<MinSequenceContainer<int>, MinSequenceContainer<int>>();
+ test<std::vector<int, min_allocator<int>>, std::vector<int, min_allocator<int>>>();
+ {
+ // Items are forwarded correctly from the input range (P2767).
+ std::pair<MoveOnly, MoveOnly> a[] = {{3, 3}, {1, 1}, {4, 4}, {1, 1}, {5, 5}};
+ std::flat_multimap<MoveOnly, MoveOnly> m;
+ m.insert_range(a | std::views::as_rvalue);
+ std::pair<MoveOnly, MoveOnly> expected[] = {{1, 1}, {1, 1}, {3, 3}, {4, 4}, {5, 5}};
+ assert(std::ranges::equal(m, expected));
+ }
+ {
+ // The element type of the range doesn't need to be std::pair (P2767).
+ std::pair<int, int> pa[] = {{3, 3}, {1, 1}, {4, 4}, {1, 1}, {5, 5}};
+ std::deque<std::reference_wrapper<std::pair<int, int>>> a(pa, pa + 5);
+ std::flat_multimap<int, int> m;
+ m.insert_range(a);
+ std::pair<int, int> expected[] = {{1, 1}, {1, 1}, {3, 3}, {4, 4}, {5, 5}};
+ assert(std::ranges::equal(m, expected));
+ }
+ {
+ auto insert_func = [](auto& m, const auto& newValues) { m.insert_range(newValues); };
+ test_insert_range_exception_guarantee(insert_func);
+ }
+ return 0;
+}
diff --git a/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.modifiers/insert_rv.pass.cpp b/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.modifiers/insert_rv.pass.cpp
new file mode 100644
index 0000000000000..573150248ca48
--- /dev/null
+++ b/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.modifiers/insert_rv.pass.cpp
@@ -0,0 +1,116 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+// UNSUPPORTED: c++03, c++11, c++14, c++17, c++20
+
+// <flat_map>
+
+// class flat_multimap
+
+// iterator insert( value_type&& v);
+
+#include <flat_map>
+#include <cassert>
+#include <deque>
+
+#include "MinSequenceContainer.h"
+#include "MoveOnly.h"
+#include "min_allocator.h"
+#include "test_macros.h"
+#include "../helpers.h"
+
+template <class Container, class Pair>
+void do_insert_rv_test() {
+ using M = Container;
+ using P = Pair;
+ using R = typename M::iterator;
+ M m;
+ std::same_as<R> decltype(auto) r = m.insert(P(2, 2));
+ assert(r == m.begin());
+ assert(m.size() == 1);
+ assert(r->first == 2);
+ assert(r->second == 2);
+
+ r = m.insert(P(1, 1));
+ assert(r == m.begin());
+ assert(m.size() == 2);
+ assert(r->first == 1);
+ assert(r->second == 1);
+
+ r = m.insert(P(3, 3));
+ assert(r == std::ranges::prev(m.end()));
+ assert(m.size() == 3);
+ assert(r->first == 3);
+ assert(r->second == 3);
+
+ r = m.insert(P(3, 3));
+ assert(r == std::ranges::prev(m.end()));
+ assert(m.size() == 4);
+ assert(r->first == 3);
+ assert(r->second == 3);
+}
+
+template <class KeyContainer, class ValueContainer>
+void test() {
+ using Key = typename KeyContainer::value_type;
+ using Value = typename ValueContainer::value_type;
+ using M = std::flat_multimap<Key, Value, TransparentComparator, KeyContainer, ValueContainer>;
+
+ using P = std::pair<Key, Value>;
+ using CP = std::pair<const Key, Value>;
+
+ do_insert_rv_test<M, P>();
+ do_insert_rv_test<M, CP>();
+}
+
+int main(int, char**) {
+ test<std::vector<int>, std::vector<MoveOnly>>();
+ test<std::deque<int>, std::vector<MoveOnly>>();
+ test<MinSequenceContainer<int>, MinSequenceContainer<MoveOnly>>();
+ test<std::vector<int, min_allocator<int>>, std::vector<MoveOnly, min_allocator<MoveOnly>>>();
+
+ {
+ using M = std::flat_multimap<int, MoveOnly>;
+ using R = M::iterator;
+ M m;
+ R r = m.insert({2, MoveOnly(2)});
+ assert(r == m.begin());
+ assert(m.size() == 1);
+ assert(r->first == 2);
+ assert(r->second == 2);
+
+ r = m.insert({1, MoveOnly(1)});
+ assert(r == m.begin());
+ assert(m.size() == 2);
+ assert(r->first == 1);
+ assert(r->second == 1);
+
+ r = m.insert({3, MoveOnly(3)});
+ assert(r == std::ranges::prev(m.end()));
+ assert(m.size() == 3);
+ assert(r->first == 3);
+ assert(r->second == 3);
+
+ r = m.insert({3, MoveOnly(3)});
+ assert(r == std::ranges::prev(m.end()));
+ assert(m.size() == 4);
+ assert(r->first == 3);
+ assert(r->second == 3);
+ }
+ {
+ auto insert_func = [](auto& m, auto key_arg, auto value_arg) {
+ using FlatMap = std::decay_t<decltype(m)>;
+ using value_type = typename FlatMap::value_type;
+ value_type p(std::piecewise_construct, std::tuple(key_arg), std::tuple(value_arg));
+ m.insert(std::move(p));
+ };
+ test_emplace_exception_guarantee(insert_func);
+ }
+
+ return 0;
+}
diff --git a/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.modifiers/insert_sorted_initializer_list.pass.cpp b/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.modifiers/insert_sorted_initializer_list.pass.cpp
new file mode 100644
index 0000000000000..334dff0a0d2f6
--- /dev/null
+++ b/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.modifiers/insert_sorted_initializer_list.pass.cpp
@@ -0,0 +1,66 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+// UNSUPPORTED: c++03, c++11, c++14, c++17, c++20
+
+// <flat_map>
+
+// class flat_multimap
+
+// void insert(sorted_equivalent_t, initializer_list<value_type> il);
+
+#include <flat_map>
+#include <cassert>
+#include <functional>
+#include <deque>
+
+#include "MinSequenceContainer.h"
+#include "../helpers.h"
+#include "test_macros.h"
+#include "min_allocator.h"
+
+template <class KeyContainer, class ValueContainer>
+void test() {
+ using Key = typename KeyContainer::value_type;
+ using Value = typename ValueContainer::value_type;
+ using M = std::flat_multimap<Key, Value, std::less<Key>, KeyContainer, ValueContainer>;
+
+ using V = std::pair<const Key, Value>;
+ M m = {{1, 1}, {1, 1.5}, {1, 2}, {3, 1}, {3, 1.5}, {3, 2}};
+ m.insert(std::sorted_equivalent,
+ {
+ {0, 1},
+ {1, 2},
+ {1, 3},
+ {2, 1},
+ {2, 4},
+ {4, 1},
+ });
+ assert(m.size() == 12);
+ V expected[] = {{0, 1}, {1, 1}, {1, 1.5}, {1, 2}, {1, 2}, {1, 3}, {2, 1}, {2, 4}, {3, 1}, {3, 1.5}, {3, 2}, {4, 1}};
+ assert(std::ranges::equal(m, expected));
+}
+
+int main(int, char**) {
+ test<std::vector<int>, std::vector<double>>();
+ test<std::deque<int>, std::vector<double>>();
+ test<MinSequenceContainer<int>, MinSequenceContainer<double>>();
+ test<std::vector<int, min_allocator<int>>, std::vector<double, min_allocator<double>>>();
+
+ {
+ auto insert_func = [](auto& m, const auto& newValues) {
+ using FlatMap = std::decay_t<decltype(m)>;
+ using value_type = typename FlatMap::value_type;
+ std::initializer_list<value_type> il = {{newValues[0].first, newValues[0].second}};
+ m.insert(std::sorted_equivalent, il);
+ };
+ test_insert_range_exception_guarantee(insert_func);
+ }
+
+ return 0;
+}
diff --git a/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.modifiers/insert_sorted_iter_iter.pass.cpp b/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.modifiers/insert_sorted_iter_iter.pass.cpp
new file mode 100644
index 0000000000000..37808470a2cf7
--- /dev/null
+++ b/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.modifiers/insert_sorted_iter_iter.pass.cpp
@@ -0,0 +1,94 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+// UNSUPPORTED: c++03, c++11, c++14, c++17, c++20
+
+// <flat_map>
+
+// class flat_multimap
+
+// template <class InputIterator>
+// void insert(sorted_equivalent_t, InputIterator first, InputIterator last);
+
+#include <flat_map>
+#include <cassert>
+#include <functional>
+#include <deque>
+
+#include "MinSequenceContainer.h"
+#include "../helpers.h"
+#include "test_macros.h"
+#include "test_iterators.h"
+#include "min_allocator.h"
+
+// test constraint InputIterator
+template <class M, class... Args>
+concept CanInsert = requires(M m, Args&&... args) { m.insert(std::forward<Args>(args)...); };
+
+using Map = std::flat_multimap<int, int>;
+using Pair = std::pair<int, int>;
+
+static_assert(CanInsert<Map, std::sorted_equivalent_t, Pair*, Pair*>);
+static_assert(CanInsert<Map, std::sorted_equivalent_t, cpp17_input_iterator<Pair*>, cpp17_input_iterator<Pair*>>);
+static_assert(!CanInsert<Map, std::sorted_equivalent_t, int, int>);
+static_assert(!CanInsert<Map, std::sorted_equivalent_t, cpp20_input_iterator<Pair*>, cpp20_input_iterator<Pair*>>);
+
+template <class KeyContainer, class ValueContainer>
+void test() {
+ using Key = typename KeyContainer::value_type;
+ using Value = typename ValueContainer::value_type;
+ using M = std::flat_multimap<Key, Value, std::less<Key>, KeyContainer, ValueContainer>;
+ using P = std::pair<Key, Value>;
+
+ P ar1[] = {
+ P(1, 1),
+ P(1, 0),
+ P(2, 1),
+ P(2, 3),
+ P(3, 1),
+ };
+
+ P ar2[] = {
+ P(0, 1),
+ P(2, 2),
+ P(2, 5),
+ P(4, 1),
+ P(4, 4),
+ };
+
+ M m;
+ m.insert(std::sorted_equivalent,
+ cpp17_input_iterator<P*>(ar1),
+ cpp17_input_iterator<P*>(ar1 + sizeof(ar1) / sizeof(ar1[0])));
+ assert(m.size() == 5);
+ P expected[] = {{1, 1}, {1, 0}, {2, 1}, {2, 3}, {3, 1}};
+ assert(std::ranges::equal(m, expected));
+
+ m.insert(std::sorted_equivalent,
+ cpp17_input_iterator<P*>(ar2),
+ cpp17_input_iterator<P*>(ar2 + sizeof(ar2) / sizeof(ar2[0])));
+ assert(m.size() == 10);
+ P expected2[] = {{0, 1}, {1, 1}, {1, 0}, {2, 1}, {2, 3}, {2, 2}, {2, 5}, {3, 1}, {4, 1}, {4, 4}};
+ assert(std::ranges::equal(m, expected2));
+}
+
+int main(int, char**) {
+ test<std::vector<int>, std::vector<double>>();
+ test<std::deque<int>, std::vector<double>>();
+ test<MinSequenceContainer<int>, MinSequenceContainer<double>>();
+ test<std::vector<int, min_allocator<int>>, std::vector<double, min_allocator<double>>>();
+
+ {
+ auto insert_func = [](auto& m, const auto& newValues) {
+ m.insert(std::sorted_equivalent, newValues.begin(), newValues.end());
+ };
+ test_insert_range_exception_guarantee(insert_func);
+ }
+
+ return 0;
+}
diff --git a/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.modifiers/insert_transparent.pass.cpp b/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.modifiers/insert_transparent.pass.cpp
new file mode 100644
index 0000000000000..33ca4d4e30469
--- /dev/null
+++ b/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.modifiers/insert_transparent.pass.cpp
@@ -0,0 +1,135 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+// UNSUPPORTED: c++03, c++11, c++14, c++17, c++20
+
+// <flat_map>
+
+// class flat_multimap
+
+// template<class K> iterator insert(P&& x);
+// template<class K> iterator insert(const_iterator hint, P&& x);
+
+#include <algorithm>
+#include <compare>
+#include <concepts>
+#include <deque>
+#include <flat_map>
+#include <functional>
+#include <tuple>
+
+#include "MinSequenceContainer.h"
+#include "../helpers.h"
+#include "test_macros.h"
+#include "test_iterators.h"
+#include "min_allocator.h"
+
+// Constraints: is_constructible_v<pair<key_type, mapped_type>, P> is true.
+template <class M, class... Args>
+concept CanInsert = requires(M m, Args&&... args) { m.insert(std::forward<Args>(args)...); };
+
+using Map = std::flat_multimap<int, double>;
+using Iter = Map::const_iterator;
+
+static_assert(CanInsert<Map, std::pair<short, double>&&>);
+static_assert(CanInsert<Map, Iter, std::pair<short, double>&&>);
+static_assert(CanInsert<Map, std::tuple<short, double>&&>);
+static_assert(CanInsert<Map, Iter, std::tuple<short, double>&&>);
+static_assert(!CanInsert<Map, int>);
+static_assert(!CanInsert<Map, Iter, int>);
+
+static int expensive_comparisons = 0;
+static int cheap_comparisons = 0;
+
+struct CompareCounter {
+ int i_ = 0;
+ CompareCounter(int i) : i_(i) {}
+ friend auto operator<=>(const CompareCounter& x, const CompareCounter& y) {
+ expensive_comparisons += 1;
+ return x.i_ <=> y.i_;
+ }
+ bool operator==(const CompareCounter&) const = default;
+ friend auto operator<=>(const CompareCounter& x, int y) {
+ cheap_comparisons += 1;
+ return x.i_ <=> y;
+ }
+};
+
+template <class KeyContainer, class ValueContainer>
+void test() {
+ using Key = typename KeyContainer::value_type;
+ using Value = typename ValueContainer::value_type;
+ using M = std::flat_multimap<Key, Value, std::less<Key>, KeyContainer, ValueContainer>;
+
+ {
+ // insert(P&&)
+ // Unlike flat_set, here we can't use key_compare to compare value_type versus P,
+ // so we must eagerly convert to value_type.
+ M m = {{1, 1}, {2, 2}, {3, 1}, {3, 4}, {4, 4}, {5, 5}};
+ expensive_comparisons = 0;
+ cheap_comparisons = 0;
+ std::same_as<typename M::iterator> decltype(auto) r = m.insert(std::make_pair(3, 3)); // conversion happens first
+ assert(expensive_comparisons >= 2);
+ assert(cheap_comparisons == 0);
+ assert(r == m.begin() + 4);
+
+ std::pair<int, int> expected[] = {{1, 1}, {2, 2}, {3, 1}, {3, 4}, {3, 3}, {4, 4}, {5, 5}};
+ assert(std::ranges::equal(m, expected));
+ }
+ {
+ // insert(const_iterator, P&&)
+ M m = {{1, 1}, {2, 2}, {3, 1}, {3, 4}, {4, 4}, {5, 5}};
+ expensive_comparisons = 0;
+ cheap_comparisons = 0;
+ std::same_as<typename M::iterator> auto it = m.insert(m.begin(), std::make_pair(3, 3));
+ assert(expensive_comparisons >= 2);
+ assert(cheap_comparisons == 0);
+ assert(it == m.begin() + 2);
+ std::pair<int, int> expected[] = {{1, 1}, {2, 2}, {3, 3}, {3, 1}, {3, 4}, {4, 4}, {5, 5}};
+ assert(std::ranges::equal(m, expected));
+ }
+}
+
+int main(int, char**) {
+ test<std::vector<CompareCounter>, std::vector<double>>();
+ test<std::deque<CompareCounter>, std::vector<double>>();
+ test<MinSequenceContainer<CompareCounter>, MinSequenceContainer<double>>();
+ test<std::vector<CompareCounter, min_allocator<CompareCounter>>, std::vector<double, min_allocator<double>>>();
+
+ {
+ // no ambiguity between insert(pos, P&&) and insert(first, last)
+ using M = std::flat_multimap<int, int>;
+ struct Evil {
+ operator M::value_type() const;
+ operator M::const_iterator() const;
+ };
+ std::flat_multimap<int, int> m;
+ ASSERT_SAME_TYPE(decltype(m.insert(Evil())), M::iterator);
+ ASSERT_SAME_TYPE(decltype(m.insert(m.begin(), Evil())), M::iterator);
+ ASSERT_SAME_TYPE(decltype(m.insert(m.begin(), m.end())), void);
+ }
+ {
+ auto insert_func = [](auto& m, auto key_arg, auto value_arg) {
+ using FlatMap = std::decay_t<decltype(m)>;
+ using tuple_type = std::tuple<typename FlatMap::key_type, typename FlatMap::mapped_type>;
+ tuple_type t(key_arg, value_arg);
+ m.insert(t);
+ };
+ test_emplace_exception_guarantee(insert_func);
+ }
+ {
+ auto insert_func_iter = [](auto& m, auto key_arg, auto value_arg) {
+ using FlatMap = std::decay_t<decltype(m)>;
+ using tuple_type = std::tuple<typename FlatMap::key_type, typename FlatMap::mapped_type>;
+ tuple_type t(key_arg, value_arg);
+ m.insert(m.begin(), t);
+ };
+ test_emplace_exception_guarantee(insert_func_iter);
+ }
+ return 0;
+}
diff --git a/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.modifiers/replace.pass.cpp b/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.modifiers/replace.pass.cpp
new file mode 100644
index 0000000000000..86fbaff468ab6
--- /dev/null
+++ b/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.modifiers/replace.pass.cpp
@@ -0,0 +1,82 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+// UNSUPPORTED: c++03, c++11, c++14, c++17, c++20
+
+// <flat_map>
+
+// class flat_multimap
+
+// void replace(key_container_type&& key_cont, mapped_container_type&& mapped_cont);
+
+#include <algorithm>
+#include <deque>
+#include <concepts>
+#include <flat_map>
+#include <functional>
+
+#include "MinSequenceContainer.h"
+#include "../helpers.h"
+#include "test_macros.h"
+#include "min_allocator.h"
+
+template <class T, class... Args>
+concept CanReplace = requires(T t, Args&&... args) { t.replace(std::forward<Args>(args)...); };
+
+using Map = std::flat_multimap<int, int>;
+static_assert(CanReplace<Map, std::vector<int>, std::vector<int>>);
+static_assert(!CanReplace<Map, const std::vector<int>&, std::vector<int>>);
+static_assert(!CanReplace<Map, std::vector<int>, const std::vector<int>&>);
+static_assert(!CanReplace<Map, const std::vector<int>&, const std::vector<int>&>);
+
+template <class KeyContainer, class ValueContainer>
+void test() {
+ using Key = typename KeyContainer::value_type;
+ using Value = typename ValueContainer::value_type;
+ using M = std::flat_multimap<Key, Value, std::less<Key>, KeyContainer, ValueContainer>;
+
+ M m = M({1, 1, 3}, {4, 5, 6});
+ KeyContainer new_keys = {7, 7};
+ ValueContainer new_values = {9, 10};
+ auto expected_keys = new_keys;
+ auto expected_values = new_values;
+ m.replace(std::move(new_keys), std::move(new_values));
+ assert(m.size() == 2);
+ assert(std::ranges::equal(m.keys(), expected_keys));
+ assert(std::ranges::equal(m.values(), expected_values));
+}
+
+int main(int, char**) {
+ test<std::vector<int>, std::vector<double>>();
+ test<std::deque<int>, std::vector<double>>();
+ test<MinSequenceContainer<int>, MinSequenceContainer<double>>();
+ test<std::vector<int, min_allocator<int>>, std::vector<double, min_allocator<double>>>();
+
+ {
+#ifndef TEST_HAS_NO_EXCEPTIONS
+ using KeyContainer = std::vector<int>;
+ using ValueContainer = ThrowOnMoveContainer<int>;
+ using M = std::flat_multimap<int, int, std::ranges::less, KeyContainer, ValueContainer>;
+
+ M m;
+ m.emplace(1, 1);
+ m.emplace(2, 2);
+ try {
+ KeyContainer new_keys{3, 4};
+ ValueContainer new_values{5, 6};
+ m.replace(std::move(new_keys), std::move(new_values));
+ assert(false);
+ } catch (int) {
+ check_invariant(m);
+ // In libc++, we clear the map
+ LIBCPP_ASSERT(m.size() == 0);
+ }
+#endif
+ }
+ return 0;
+}
diff --git a/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.modifiers/swap_exception.pass.cpp b/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.modifiers/swap_exception.pass.cpp
new file mode 100644
index 0000000000000..a1252f301309a
--- /dev/null
+++ b/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.modifiers/swap_exception.pass.cpp
@@ -0,0 +1,80 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+// UNSUPPORTED: c++03, c++11, c++14, c++17, c++20
+// `check_assertion.h` requires Unix headers and regex support.
+// REQUIRES: has-unix-headers
+// UNSUPPORTED: no-localization
+// UNSUPPORTED: no-exceptions
+
+// <flat_map>
+
+// class flat_multimap
+
+// void swap(flat_multimap& y) noexcept;
+// friend void swap(flat_multimap& x, flat_multimap& y) noexcept
+
+// Test that std::terminate is called if any exception is thrown during swap
+
+#include <flat_map>
+#include <cassert>
+#include <deque>
+#include <functional>
+#include <vector>
+
+#include "test_macros.h"
+#include "../helpers.h"
+#include "check_assertion.h"
+
+template <class F>
+void test_swap_exception_guarantee([[maybe_unused]] F&& swap_function) {
+ {
+ // key swap throws
+ using KeyContainer = ThrowOnMoveContainer<int>;
+ using ValueContainer = std::vector<int>;
+ using M = std::flat_multimap<int, int, TransparentComparator, KeyContainer, ValueContainer>;
+
+ M m1, m2;
+ m1.emplace(1, 1);
+ m1.emplace(1, 2);
+ m2.emplace(3, 3);
+ m2.emplace(3, 4);
+ // swap is noexcept
+ EXPECT_STD_TERMINATE([&] { swap_function(m1, m2); });
+ }
+
+ {
+ // value swap throws
+ using KeyContainer = std::vector<int>;
+ using ValueContainer = ThrowOnMoveContainer<int>;
+ using M = std::flat_multimap<int, int, TransparentComparator, KeyContainer, ValueContainer>;
+
+ M m1, m2;
+ m1.emplace(1, 1);
+ m1.emplace(1, 2);
+ m2.emplace(3, 3);
+ m2.emplace(3, 4);
+
+ // swap is noexcept
+ EXPECT_STD_TERMINATE([&] { swap_function(m1, m2); });
+ }
+}
+
+int main(int, char**) {
+ {
+ auto swap_func = [](auto& m1, auto& m2) { swap(m1, m2); };
+ test_swap_exception_guarantee(swap_func);
+ }
+
+ {
+ auto swap_func = [](auto& m1, auto& m2) { m1.swap(m2); };
+ test_swap_exception_guarantee(swap_func);
+ }
+
+ return 0;
+}
diff --git a/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.modifiers/swap_free.pass.cpp b/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.modifiers/swap_free.pass.cpp
new file mode 100644
index 0000000000000..f96155d714dc9
--- /dev/null
+++ b/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.modifiers/swap_free.pass.cpp
@@ -0,0 +1,99 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+// UNSUPPORTED: c++03, c++11, c++14, c++17, c++20
+
+// <flat_map>
+
+// class flat_multimap
+
+// friend void swap(flat_multimap& x, flat_multimap& y) noexcept
+
+#include <flat_map>
+#include <cassert>
+#include <deque>
+#include <functional>
+#include <vector>
+
+#include "MinSequenceContainer.h"
+#include "MoveOnly.h"
+#include "min_allocator.h"
+#include "test_macros.h"
+#include "../helpers.h"
+
+// test noexcept
+
+template <class T>
+concept NoExceptAdlSwap = requires(T t1, T t2) {
+ { swap(t1, t2) } noexcept;
+};
+
+static_assert(NoExceptAdlSwap<std::flat_multimap<int, int>>);
+
+#ifndef TEST_HAS_NO_EXCEPTIONS
+static_assert(NoExceptAdlSwap<
+ std::flat_multimap<int, int, std::less<int>, ThrowOnMoveContainer<int>, ThrowOnMoveContainer<int>>>);
+#endif
+
+template <class KeyContainer, class ValueContainer>
+void test() {
+ using Key = typename KeyContainer::value_type;
+ using Value = typename ValueContainer::value_type;
+ using M = std::flat_multimap<Key, Value, std::less<Key>, KeyContainer, ValueContainer>;
+ using V = std::pair<const Key, Value>;
+
+ {
+ M m1;
+ M m2;
+ M m1_save = m1;
+ M m2_save = m2;
+ swap(m1, m2);
+ assert(m1 == m2_save);
+ assert(m2 == m1_save);
+ }
+ {
+ V ar2[] = {V(5, 5), V(5, 6), V(5, 7), V(8, 8), V(9, 9), V(10, 10), V(10, 11), V(10, 12)};
+ M m1;
+ M m2(ar2, ar2 + sizeof(ar2) / sizeof(ar2[0]));
+ M m1_save = m1;
+ M m2_save = m2;
+ swap(m1, m2);
+ assert(m1 == m2_save);
+ assert(m2 == m1_save);
+ }
+ {
+ V ar1[] = {V(1, 1), V(1, 2), V(3, 3), V(4, 4)};
+ M m1(ar1, ar1 + sizeof(ar1) / sizeof(ar1[0]));
+ M m2;
+ M m1_save = m1;
+ M m2_save = m2;
+ swap(m1, m2);
+ assert(m1 == m2_save);
+ assert(m2 == m1_save);
+ }
+ {
+ V ar1[] = {V(1, 1), V(1, 2), V(3, 3), V(4, 4)};
+ V ar2[] = {V(5, 5), V(5, 6), V(5, 7), V(8, 8), V(9, 9), V(10, 10), V(10, 11), V(10, 12)};
+ M m1(ar1, ar1 + sizeof(ar1) / sizeof(ar1[0]));
+ M m2(ar2, ar2 + sizeof(ar2) / sizeof(ar2[0]));
+ M m1_save = m1;
+ M m2_save = m2;
+ swap(m1, m2);
+ assert(m1 == m2_save);
+ assert(m2 == m1_save);
+ }
+}
+
+int main(int, char**) {
+ test<std::vector<int>, std::vector<double>>();
+ test<std::deque<int>, std::vector<double>>();
+ test<MinSequenceContainer<int>, MinSequenceContainer<double>>();
+ test<std::vector<int, min_allocator<int>>, std::vector<double, min_allocator<double>>>();
+
+ return 0;
+}
diff --git a/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.modifiers/swap_member.pass.cpp b/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.modifiers/swap_member.pass.cpp
new file mode 100644
index 0000000000000..ab7be3b8ac22e
--- /dev/null
+++ b/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.modifiers/swap_member.pass.cpp
@@ -0,0 +1,97 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+// UNSUPPORTED: c++03, c++11, c++14, c++17, c++20
+
+// <flat_map>
+
+// class flat_multimap
+
+// void swap(flat_multimap& y) noexcept;
+
+#include <flat_map>
+#include <cassert>
+#include <deque>
+#include <functional>
+#include <vector>
+
+#include "MinSequenceContainer.h"
+#include "MoveOnly.h"
+#include "min_allocator.h"
+#include "test_macros.h"
+#include "../helpers.h"
+
+// test noexcept
+
+template <class T>
+concept NoExceptMemberSwap = requires(T t1, T t2) {
+ { t1.swap(t2) } noexcept;
+};
+
+static_assert(NoExceptMemberSwap<std::flat_multimap<int, int>>);
+#ifndef TEST_HAS_NO_EXCEPTIONS
+static_assert(NoExceptMemberSwap<
+ std::flat_multimap<int, int, std::less<int>, ThrowOnMoveContainer<int>, ThrowOnMoveContainer<int>>>);
+#endif
+
+template <class KeyContainer, class ValueContainer>
+void test() {
+ using Key = typename KeyContainer::value_type;
+ using Value = typename ValueContainer::value_type;
+ using M = std::flat_multimap<Key, Value, std::less<Key>, KeyContainer, ValueContainer>;
+ using V = std::pair<const Key, Value>;
+ {
+ M m1;
+ M m2;
+ M m1_save = m1;
+ M m2_save = m2;
+ m1.swap(m2);
+ assert(m1 == m2_save);
+ assert(m2 == m1_save);
+ }
+ {
+ V ar2[] = {V(5, 5), V(5, 6), V(7, 7), V(8, 8), V(9, 9), V(10, 10), V(10, 11), V(12, 12)};
+ M m1;
+ M m2(ar2, ar2 + sizeof(ar2) / sizeof(ar2[0]));
+ M m1_save = m1;
+ M m2_save = m2;
+ m1.swap(m2);
+ assert(m1 == m2_save);
+ assert(m2 == m1_save);
+ }
+ {
+ V ar1[] = {V(1, 1), V(1, 2), V(3, 3), V(4, 4)};
+ M m1(ar1, ar1 + sizeof(ar1) / sizeof(ar1[0]));
+ M m2;
+ M m1_save = m1;
+ M m2_save = m2;
+ m1.swap(m2);
+ assert(m1 == m2_save);
+ assert(m2 == m1_save);
+ }
+ {
+ V ar1[] = {V(1, 1), V(1, 2), V(3, 3), V(4, 4)};
+ V ar2[] = {V(5, 5), V(5, 6), V(7, 7), V(8, 8), V(9, 9), V(10, 10), V(10, 11), V(12, 12)};
+ M m1(ar1, ar1 + sizeof(ar1) / sizeof(ar1[0]));
+ M m2(ar2, ar2 + sizeof(ar2) / sizeof(ar2[0]));
+ M m1_save = m1;
+ M m2_save = m2;
+ m1.swap(m2);
+ assert(m1 == m2_save);
+ assert(m2 == m1_save);
+ }
+}
+
+int main(int, char**) {
+ test<std::vector<int>, std::vector<double>>();
+ test<std::deque<int>, std::vector<double>>();
+ test<MinSequenceContainer<int>, MinSequenceContainer<double>>();
+ test<std::vector<int, min_allocator<int>>, std::vector<double, min_allocator<double>>>();
+
+ return 0;
+}
diff --git a/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.observers/comp.pass.cpp b/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.observers/comp.pass.cpp
new file mode 100644
index 0000000000000..47140132c6e47
--- /dev/null
+++ b/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.observers/comp.pass.cpp
@@ -0,0 +1,98 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+// UNSUPPORTED: c++03, c++11, c++14, c++17, c++20
+
+// <flat_map>
+
+// class flat_multimap
+
+// key_compare key_comp() const;
+// value_compare value_comp() const;
+
+#include <cassert>
+#include <flat_map>
+#include <functional>
+#include <utility>
+#include <vector>
+
+#include "test_macros.h"
+
+int main(int, char**) {
+ {
+ using M = std::flat_multimap<int, char>;
+ using Comp = std::less<int>; // the default
+ M m = {};
+ ASSERT_SAME_TYPE(M::key_compare, Comp);
+ static_assert(!std::is_same_v<M::value_compare, Comp>);
+ ASSERT_SAME_TYPE(decltype(m.key_comp()), Comp);
+ ASSERT_SAME_TYPE(decltype(m.value_comp()), M::value_compare);
+ Comp kc = m.key_comp();
+ assert(kc(1, 2));
+ assert(!kc(2, 1));
+ auto vc = m.value_comp();
+ ASSERT_SAME_TYPE(decltype(vc(std::make_pair(1, 2), std::make_pair(1, 2))), bool);
+ assert(vc({1, '2'}, {2, '1'}));
+ assert(!vc({2, '1'}, {1, '2'}));
+ }
+ {
+ using Comp = std::function<bool(int, int)>;
+ using M = std::flat_multimap<int, int, Comp>;
+ Comp comp = std::greater<int>();
+ M m({}, comp);
+ ASSERT_SAME_TYPE(M::key_compare, Comp);
+ ASSERT_SAME_TYPE(decltype(m.key_comp()), Comp);
+ ASSERT_SAME_TYPE(decltype(m.value_comp()), M::value_compare);
+ Comp kc = m.key_comp();
+ assert(!kc(1, 2));
+ assert(kc(2, 1));
+ auto vc = m.value_comp();
+ auto a = std::make_pair(1, 2);
+ ASSERT_SAME_TYPE(decltype(vc(a, a)), bool);
+ static_assert(!noexcept(vc(a, a)));
+ assert(!vc({1, 2}, {2, 1}));
+ assert(vc({2, 1}, {1, 2}));
+ }
+ {
+ using Comp = std::less<>;
+ using M = std::flat_multimap<int, int, Comp>;
+ M m = {};
+ ASSERT_SAME_TYPE(M::key_compare, Comp);
+ ASSERT_SAME_TYPE(decltype(m.key_comp()), Comp);
+ ASSERT_SAME_TYPE(decltype(m.value_comp()), M::value_compare);
+ Comp kc = m.key_comp();
+ assert(kc(1, 2));
+ assert(!kc(2, 1));
+ auto vc = m.value_comp();
+ auto a = std::make_pair(1, 2);
+ ASSERT_SAME_TYPE(decltype(vc(a, a)), bool);
+ assert(vc({1, 2}, {2, 1}));
+ assert(!vc({2, 1}, {1, 2}));
+ }
+ {
+ using Comp = std::function<bool(const std::vector<int>&, const std::vector<int>&)>;
+ using M = std::flat_multimap<std::vector<int>, int, Comp>;
+ Comp comp = [i = 1](const auto& x, const auto& y) { return x[i] < y[i]; };
+ M m({}, comp);
+ auto vc = m.value_comp();
+ static_assert(sizeof(vc) >= sizeof(Comp));
+ comp = nullptr;
+ m = M({}, nullptr);
+ assert(m.key_comp() == nullptr);
+ // At this point, m.key_comp() is disengaged.
+ // But the std::function captured by copy inside `vc` remains valid.
+ auto a = std::make_pair(std::vector<int>{2, 1, 4}, 42);
+ auto b = std::make_pair(std::vector<int>{1, 2, 3}, 42);
+ auto c = std::make_pair(std::vector<int>{0, 3, 2}, 42);
+ assert(vc(a, b));
+ assert(vc(b, c));
+ assert(!vc(b, a));
+ assert(!vc(c, b));
+ }
+ return 0;
+}
diff --git a/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.observers/keys_values.pass.cpp b/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.observers/keys_values.pass.cpp
new file mode 100644
index 0000000000000..c7c674c034bca
--- /dev/null
+++ b/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.observers/keys_values.pass.cpp
@@ -0,0 +1,59 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+// UNSUPPORTED: c++03, c++11, c++14, c++17, c++20
+
+// <flat_map>
+
+// class flat_multimap
+
+// const key_container_type& keys() const noexcept
+// const mapped_container_type& values() const noexcept
+
+#include <algorithm>
+#include <cassert>
+#include <flat_map>
+#include <functional>
+#include <utility>
+#include <vector>
+#include <deque>
+#include <string>
+
+#include "MinSequenceContainer.h"
+#include "test_macros.h"
+#include "test_allocator.h"
+#include "min_allocator.h"
+
+template <class KeyContainer, class ValueContainer>
+void test() {
+ using Key = typename KeyContainer::value_type;
+ using Value = typename ValueContainer::value_type;
+ using M = std::flat_multimap<Key, Value, std::less<Key>, KeyContainer, ValueContainer>;
+
+ const M m = {{4, 'a'}, {2, 'b'}, {2, 'e'}, {3, 'c'}};
+ std::same_as<const KeyContainer&> decltype(auto) keys = m.keys();
+ std::same_as<const ValueContainer&> decltype(auto) values = m.values();
+
+ // noexcept
+ static_assert(noexcept(m.keys()));
+ static_assert(noexcept(m.values()));
+
+ auto expected_keys = {2, 2, 3, 4};
+ auto expected_values = {'b', 'e', 'c', 'a'};
+ assert(std::ranges::equal(keys, expected_keys));
+ assert(std::ranges::equal(values, expected_values));
+}
+
+int main(int, char**) {
+ test<std::vector<int>, std::vector<char>>();
+ test<std::deque<int>, std::vector<char>>();
+ test<MinSequenceContainer<int>, MinSequenceContainer<char>>();
+ test<std::vector<int, min_allocator<int>>, std::vector<char, min_allocator<char>>>();
+
+ return 0;
+}
diff --git a/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.operations/contains.pass.cpp b/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.operations/contains.pass.cpp
new file mode 100644
index 0000000000000..b3ea0b65a3d93
--- /dev/null
+++ b/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.operations/contains.pass.cpp
@@ -0,0 +1,72 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+// UNSUPPORTED: c++03, c++11, c++14, c++17, c++20
+
+// <flat_map>
+
+// class flat_multimap
+
+// bool contains(const key_type& x) const;
+
+#include <cassert>
+#include <deque>
+#include <flat_map>
+#include <functional>
+#include <utility>
+
+#include "MinSequenceContainer.h"
+#include "test_macros.h"
+#include "min_allocator.h"
+
+template <class KeyContainer, class ValueContainer>
+void test() {
+ using Key = typename KeyContainer::value_type;
+ using Value = typename ValueContainer::value_type;
+ {
+ using M = std::flat_multimap<Key, Value, std::less<>, KeyContainer, ValueContainer>;
+ M m = {{1, 1}, {2, 2}, {2, 3}, {4, 4}, {5, 5}, {8, 1}, {8, 2}, {8, 8}};
+ assert(!m.contains(0));
+ assert(m.contains(1));
+ assert(m.contains(2));
+ assert(!m.contains(3));
+ assert(m.contains(4));
+ assert(m.contains(5));
+ assert(!m.contains(6));
+ assert(!m.contains(7));
+ assert(std::as_const(m).contains(8));
+ assert(!std::as_const(m).contains(9));
+ m.clear();
+ assert(!m.contains(1));
+ }
+ {
+ using M = std::flat_multimap<Key, Value, std::greater<int>, KeyContainer, ValueContainer>;
+ M m = {{1, 0}, {2, 0}, {4, 0}, {2, 1}, {5, 1}, {5, 2}, {5, 0}, {8, 0}};
+ assert(!m.contains(0));
+ assert(m.contains(1));
+ assert(m.contains(2));
+ assert(!m.contains(3));
+ assert(m.contains(4));
+ assert(m.contains(5));
+ assert(!m.contains(6));
+ assert(!m.contains(7));
+ assert(std::as_const(m).contains(8));
+ assert(!std::as_const(m).contains(9));
+ m.clear();
+ assert(!m.contains(1));
+ }
+}
+
+int main(int, char**) {
+ test<std::vector<int>, std::vector<int>>();
+ test<std::deque<int>, std::vector<int>>();
+ test<MinSequenceContainer<int>, MinSequenceContainer<int>>();
+ test<std::vector<int, min_allocator<int>>, std::vector<int, min_allocator<int>>>();
+
+ return 0;
+}
diff --git a/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.operations/contains_transparent.pass.cpp b/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.operations/contains_transparent.pass.cpp
new file mode 100644
index 0000000000000..8a66ec63768d7
--- /dev/null
+++ b/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.operations/contains_transparent.pass.cpp
@@ -0,0 +1,73 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+// UNSUPPORTED: c++03, c++11, c++14, c++17, c++20
+
+// <flat_map>
+
+// class flat_multimap
+
+// template<class K> bool contains(const K& x) const;
+
+#include <cassert>
+#include <flat_map>
+#include <string>
+#include <utility>
+#include <deque>
+
+#include "MinSequenceContainer.h"
+#include "../helpers.h"
+#include "test_macros.h"
+#include "min_allocator.h"
+
+// Constraints: The qualified-id Compare::is_transparent is valid and denotes a type.
+template <class M>
+concept CanContains = requires(M m, Transparent<int> k) { m.contains(k); };
+using TransparentMap = std::flat_multimap<int, double, TransparentComparator>;
+using NonTransparentMap = std::flat_multimap<int, double, NonTransparentComparator>;
+static_assert(CanContains<TransparentMap>);
+static_assert(CanContains<const TransparentMap>);
+static_assert(!CanContains<NonTransparentMap>);
+static_assert(!CanContains<const NonTransparentMap>);
+
+template <class KeyContainer, class ValueContainer>
+void test() {
+ using Key = typename KeyContainer::value_type;
+ using Value = typename ValueContainer::value_type;
+ using M = std::flat_multimap<Key, Value, TransparentComparator, KeyContainer, ValueContainer>;
+
+ M m = {{"alpha", 1}, {"beta", 2}, {"beta", 0}, {"epsilon", 3}, {"eta", 4}, {"eta", 1}, {"gamma", 5}};
+ ASSERT_SAME_TYPE(decltype(m.contains(Transparent<std::string>{"abc"})), bool);
+ ASSERT_SAME_TYPE(decltype(std::as_const(m).contains(Transparent<std::string>{"b"})), bool);
+ assert(m.contains(Transparent<std::string>{"alpha"}) == true);
+ assert(m.contains(Transparent<std::string>{"beta"}) == true);
+ assert(m.contains(Transparent<std::string>{"epsilon"}) == true);
+ assert(m.contains(Transparent<std::string>{"eta"}) == true);
+ assert(m.contains(Transparent<std::string>{"gamma"}) == true);
+ assert(m.contains(Transparent<std::string>{"al"}) == false);
+ assert(m.contains(Transparent<std::string>{""}) == false);
+ assert(m.contains(Transparent<std::string>{"g"}) == false);
+}
+
+int main(int, char**) {
+ test<std::vector<std::string>, std::vector<int>>();
+ test<std::deque<std::string>, std::vector<int>>();
+ test<MinSequenceContainer<std::string>, MinSequenceContainer<int>>();
+ test<std::vector<std::string, min_allocator<std::string>>, std::vector<int, min_allocator<int>>>();
+
+ {
+ bool transparent_used = false;
+ TransparentComparator c(transparent_used);
+ std::flat_multimap<int, int, TransparentComparator> m(std::sorted_equivalent, {{1, 1}, {1, 2}, {2, 2}, {3, 3}}, c);
+ assert(!transparent_used);
+ auto b = m.contains(Transparent<int>{3});
+ assert(b);
+ assert(transparent_used);
+ }
+ return 0;
+}
diff --git a/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.operations/count.pass.cpp b/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.operations/count.pass.cpp
new file mode 100644
index 0000000000000..59b88428cde3c
--- /dev/null
+++ b/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.operations/count.pass.cpp
@@ -0,0 +1,71 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+// UNSUPPORTED: c++03, c++11, c++14, c++17, c++20
+
+// <flat_map>
+
+// class flat_multimap
+
+// size_type count(const key_type& x) const;
+
+#include <cassert>
+#include <deque>
+#include <flat_map>
+#include <functional>
+#include <utility>
+
+#include "MinSequenceContainer.h"
+#include "test_macros.h"
+#include "min_allocator.h"
+
+template <class KeyContainer, class ValueContainer>
+void test() {
+ using Key = typename KeyContainer::value_type;
+ using Value = typename ValueContainer::value_type;
+
+ {
+ using M = std::flat_multimap<Key, Value, std::less<>, KeyContainer, ValueContainer>;
+ M m = {{1, 1}, {2, 2}, {2, 2}, {4, 4}, {4, 1}, {4, 3}, {4, 4}, {5, 5}, {8, 8}};
+ ASSERT_SAME_TYPE(decltype(m.count(0)), size_t);
+ assert(m.count(0) == 0);
+ assert(m.count(1) == 1);
+ assert(m.count(2) == 2);
+ assert(m.count(3) == 0);
+ assert(m.count(4) == 4);
+ assert(m.count(5) == 1);
+ assert(m.count(6) == 0);
+ assert(m.count(7) == 0);
+ assert(std::as_const(m).count(8) == 1);
+ assert(std::as_const(m).count(9) == 0);
+ }
+ {
+ using M = std::flat_multimap<Key, Value, std::greater<int>, KeyContainer, ValueContainer>;
+ M m = {{1, 0}, {2, 0}, {4, 0}, {1, 0}, {1, 2}, {8, 1}, {5, 0}, {8, 0}};
+ ASSERT_SAME_TYPE(decltype(m.count(0)), size_t);
+ assert(m.count(0) == 0);
+ assert(m.count(1) == 3);
+ assert(m.count(2) == 1);
+ assert(m.count(3) == 0);
+ assert(m.count(4) == 1);
+ assert(m.count(5) == 1);
+ assert(m.count(6) == 0);
+ assert(m.count(7) == 0);
+ assert(std::as_const(m).count(8) == 2);
+ assert(std::as_const(m).count(9) == 0);
+ }
+}
+
+int main(int, char**) {
+ test<std::vector<int>, std::vector<int>>();
+ test<std::deque<int>, std::vector<int>>();
+ test<MinSequenceContainer<int>, MinSequenceContainer<int>>();
+ test<std::vector<int, min_allocator<int>>, std::vector<int, min_allocator<int>>>();
+
+ return 0;
+}
diff --git a/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.operations/count_transparent.pass.cpp b/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.operations/count_transparent.pass.cpp
new file mode 100644
index 0000000000000..41f71065b2f75
--- /dev/null
+++ b/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.operations/count_transparent.pass.cpp
@@ -0,0 +1,83 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+// UNSUPPORTED: c++03, c++11, c++14, c++17, c++20
+
+// <flat_map>
+
+// class flat_multimap
+
+// template<class K> size_type count(const K& x) const;
+
+#include <cassert>
+#include <deque>
+#include <flat_map>
+#include <string>
+#include <utility>
+
+#include "MinSequenceContainer.h"
+#include "../helpers.h"
+#include "test_macros.h"
+#include "min_allocator.h"
+
+// Constraints: The qualified-id Compare::is_transparent is valid and denotes a type.
+template <class M>
+concept CanCount = requires(M m, Transparent<int> k) { m.count(k); };
+using TransparentMap = std::flat_multimap<int, double, TransparentComparator>;
+using NonTransparentMap = std::flat_multimap<int, double, NonTransparentComparator>;
+static_assert(CanCount<TransparentMap>);
+static_assert(CanCount<const TransparentMap>);
+static_assert(!CanCount<NonTransparentMap>);
+static_assert(!CanCount<const NonTransparentMap>);
+
+template <class KeyContainer, class ValueContainer>
+void test() {
+ using Key = typename KeyContainer::value_type;
+ using Value = typename ValueContainer::value_type;
+ using M = std::flat_multimap<Key, Value, TransparentComparator, KeyContainer, ValueContainer>;
+
+ M m = {{"alpha", 1},
+ {"beta", 2},
+ {"beta", 2},
+ {"epsilon", 3},
+ {"eta", 4},
+ {"eta", 1},
+ {"eta", 5},
+ {"gamma", 6},
+ {"gamma", 5}};
+ ASSERT_SAME_TYPE(decltype(m.count(Transparent<std::string>{"abc"})), typename M::size_type);
+ ASSERT_SAME_TYPE(decltype(std::as_const(m).count(Transparent<std::string>{"b"})), typename M::size_type);
+ assert(m.count(Transparent<std::string>{"alpha"}) == 1);
+ assert(m.count(Transparent<std::string>{"beta"}) == 2);
+ assert(m.count(Transparent<std::string>{"epsilon"}) == 1);
+ assert(m.count(Transparent<std::string>{"eta"}) == 3);
+ assert(m.count(Transparent<std::string>{"gamma"}) == 2);
+ assert(m.count(Transparent<std::string>{"al"}) == 0);
+ assert(m.count(Transparent<std::string>{""}) == 0);
+ assert(m.count(Transparent<std::string>{"g"}) == 0);
+}
+
+int main(int, char**) {
+ test<std::vector<std::string>, std::vector<int>>();
+ test<std::deque<std::string>, std::vector<int>>();
+ test<MinSequenceContainer<std::string>, MinSequenceContainer<int>>();
+ test<std::vector<std::string, min_allocator<std::string>>, std::vector<int, min_allocator<int>>>();
+
+ {
+ bool transparent_used = false;
+ TransparentComparator c(transparent_used);
+ std::flat_multimap<int, int, TransparentComparator> m(
+ std::sorted_equivalent, {{1, 1}, {2, 2}, {2, 2}, {3, 3}, {3, 3}}, c);
+ assert(!transparent_used);
+ auto n = m.count(Transparent<int>{3});
+ assert(n == 2);
+ assert(transparent_used);
+ }
+
+ return 0;
+}
diff --git a/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.operations/equal_range.pass.cpp b/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.operations/equal_range.pass.cpp
new file mode 100644
index 0000000000000..ac369b77a7f3d
--- /dev/null
+++ b/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.operations/equal_range.pass.cpp
@@ -0,0 +1,81 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+// UNSUPPORTED: c++03, c++11, c++14, c++17, c++20
+
+// <flat_map>
+
+// class flat_multimap
+
+// pair<iterator,iterator> equal_range(const key_type& k);
+// pair<const_iterator,const_iterator> equal_range(const key_type& k) const;
+
+#include <cassert>
+#include <deque>
+#include <flat_map>
+#include <functional>
+#include <utility>
+
+#include "MinSequenceContainer.h"
+#include "test_macros.h"
+#include "min_allocator.h"
+
+template <class KeyContainer, class ValueContainer>
+void test() {
+ using Key = typename KeyContainer::value_type;
+ using Value = typename ValueContainer::value_type;
+ {
+ using M = std::flat_multimap<Key, Value, std::less<>, KeyContainer, ValueContainer>;
+ using R = std::pair<typename M::iterator, typename M::iterator>;
+ using CR = std::pair<typename M::const_iterator, typename M::const_iterator>;
+ M m = {{1, 'a'}, {1, 'a'}, {1, 'A'}, {2, 'b'}, {4, 'd'}, {5, 'E'}, {5, 'e'}, {8, 'h'}, {8, 'z'}};
+ ASSERT_SAME_TYPE(decltype(m.equal_range(0)), R);
+ ASSERT_SAME_TYPE(decltype(std::as_const(m).equal_range(0)), CR);
+ auto begin = m.begin();
+ assert(m.equal_range(0) == std::pair(begin, begin));
+ assert(m.equal_range(1) == std::pair(begin, begin + 3));
+ assert(m.equal_range(2) == std::pair(begin + 3, begin + 4));
+ assert(m.equal_range(3) == std::pair(begin + 4, begin + 4));
+ assert(m.equal_range(4) == std::pair(begin + 4, begin + 5));
+ assert(m.equal_range(5) == std::pair(begin + 5, begin + 7));
+ assert(m.equal_range(6) == std::pair(begin + 7, begin + 7));
+ assert(m.equal_range(7) == std::pair(begin + 7, begin + 7));
+ assert(std::as_const(m).equal_range(8) == std::pair(m.cbegin() + 7, m.cbegin() + 9));
+ assert(std::as_const(m).equal_range(9) == std::pair(m.cbegin() + 9, m.cbegin() + 9));
+ }
+
+ {
+ using M = std::flat_multimap<Key, Value, std::greater<int>, KeyContainer, ValueContainer>;
+ using R = std::pair<typename M::iterator, typename M::iterator>;
+ using CR = std::pair<typename M::const_iterator, typename M::const_iterator>;
+ M m = {
+ {1, 'a'}, {2, 'b'}, {2, 'b'}, {2, 'c'}, {4, 'a'}, {4, 'b'}, {4, 'c'}, {4, 'd'}, {5, 'e'}, {8, 'a'}, {8, 'h'}};
+ ASSERT_SAME_TYPE(decltype(m.equal_range(0)), R);
+ ASSERT_SAME_TYPE(decltype(std::as_const(m).equal_range(0)), CR);
+ auto begin = m.begin();
+ assert(m.equal_range(0) == std::pair(begin + 11, begin + 11));
+ assert(m.equal_range(1) == std::pair(begin + 10, begin + 11));
+ assert(m.equal_range(2) == std::pair(begin + 7, begin + 10));
+ assert(m.equal_range(3) == std::pair(begin + 7, begin + 7));
+ assert(m.equal_range(4) == std::pair(begin + 3, begin + 7));
+ assert(m.equal_range(5) == std::pair(begin + 2, begin + 3));
+ assert(m.equal_range(6) == std::pair(begin + 2, begin + 2));
+ assert(m.equal_range(7) == std::pair(begin + 2, begin + 2));
+ assert(std::as_const(m).equal_range(8) == std::pair(m.cbegin(), m.cbegin() + 2));
+ assert(std::as_const(m).equal_range(9) == std::pair(m.cbegin(), m.cbegin()));
+ }
+}
+
+int main(int, char**) {
+ test<std::vector<int>, std::vector<char>>();
+ test<std::deque<int>, std::vector<char>>();
+ test<MinSequenceContainer<int>, MinSequenceContainer<char>>();
+ test<std::vector<int, min_allocator<int>>, std::vector<char, min_allocator<char>>>();
+
+ return 0;
+}
diff --git a/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.operations/equal_range_transparent.pass.cpp b/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.operations/equal_range_transparent.pass.cpp
new file mode 100644
index 0000000000000..3666492bb921f
--- /dev/null
+++ b/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.operations/equal_range_transparent.pass.cpp
@@ -0,0 +1,110 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+// UNSUPPORTED: c++03, c++11, c++14, c++17, c++20
+
+// <flat_map>
+
+// class flat_multimap
+
+// template<class K> pair<iterator,iterator> equal_range(const K& x);
+// template<class K> pair<const_iterator,const_iterator> equal_range(const K& x) const;
+
+#include <cassert>
+#include <deque>
+#include <flat_map>
+#include <string>
+#include <utility>
+
+#include "MinSequenceContainer.h"
+#include "../helpers.h"
+#include "test_macros.h"
+#include "min_allocator.h"
+
+// Constraints: The qualified-id Compare::is_transparent is valid and denotes a type.
+template <class M>
+concept CanEqualRange = requires(M m, Transparent<int> k) { m.equal_range(k); };
+using TransparentMap = std::flat_multimap<int, double, TransparentComparator>;
+using NonTransparentMap = std::flat_multimap<int, double, NonTransparentComparator>;
+static_assert(CanEqualRange<TransparentMap>);
+static_assert(CanEqualRange<const TransparentMap>);
+static_assert(!CanEqualRange<NonTransparentMap>);
+static_assert(!CanEqualRange<const NonTransparentMap>);
+
+template <class KeyContainer, class ValueContainer>
+void test() {
+ using Key = typename KeyContainer::value_type;
+ using Value = typename ValueContainer::value_type;
+ using M = std::flat_multimap<Key, Value, TransparentComparator, KeyContainer, ValueContainer>;
+
+ using R = std::pair<typename M::iterator, typename M::iterator>;
+ using CR = std::pair<typename M::const_iterator, typename M::const_iterator>;
+ M m = {{"alpha", 1},
+ {"alpha", 1},
+ {"alpha", 3},
+ {"beta", 2},
+ {"epsilon", 3},
+ {"epsilon", 0},
+ {"eta", 4},
+ {"gamma", 5},
+ {"gamma", 1}};
+ const auto& cm = m;
+ ASSERT_SAME_TYPE(decltype(m.equal_range(Transparent<std::string>{"abc"})), R);
+ ASSERT_SAME_TYPE(decltype(std::as_const(m).equal_range(Transparent<std::string>{"b"})), CR);
+
+ auto test_found = [&](auto&& map, const auto& expected_key, std::initializer_list<Value> expected_values) {
+ auto [first, last] = map.equal_range(Transparent<std::string>{expected_key});
+ auto expected_range =
+ expected_values | std::views::transform([&](auto&& val) { return std::pair(expected_key, val); });
+ assert(std::ranges::equal(std::ranges::subrange(first, last), expected_range));
+ };
+
+ auto test_not_found = [&](auto&& map, const std::string& expected_key, long expected_offset) {
+ auto [first, last] = map.equal_range(Transparent<std::string>{expected_key});
+ assert(first == last);
+ assert(first - m.begin() == expected_offset);
+ };
+
+ test_found(m, "alpha", {1, 1, 3});
+ test_found(m, "beta", {2});
+ test_found(m, "epsilon", {3, 0});
+ test_found(m, "eta", {4});
+ test_found(m, "gamma", {5, 1});
+ test_found(cm, "alpha", {1, 1, 3});
+ test_found(cm, "beta", {2});
+ test_found(cm, "epsilon", {3, 0});
+ test_found(cm, "eta", {4});
+ test_found(cm, "gamma", {5, 1});
+
+ test_not_found(m, "charlie", 4);
+ test_not_found(m, "aaa", 0);
+ test_not_found(m, "zzz", 9);
+ test_not_found(cm, "charlie", 4);
+ test_not_found(cm, "aaa", 0);
+ test_not_found(cm, "zzz", 9);
+}
+
+int main(int, char**) {
+ test<std::vector<std::string>, std::vector<int>>();
+ test<std::deque<std::string>, std::vector<int>>();
+ test<MinSequenceContainer<std::string>, MinSequenceContainer<int>>();
+ test<std::vector<std::string, min_allocator<std::string>>, std::vector<int, min_allocator<int>>>();
+
+ {
+ bool transparent_used = false;
+ TransparentComparator c(transparent_used);
+ std::flat_multimap<int, int, TransparentComparator> m(std::sorted_equivalent, {{1, 1}, {2, 2}, {3, 1}, {3, 3}}, c);
+ assert(!transparent_used);
+ auto p = m.equal_range(Transparent<int>{3});
+ assert(p.first == m.begin() + 2);
+ assert(p.second == m.end());
+ assert(transparent_used);
+ }
+
+ return 0;
+}
diff --git a/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.operations/find.pass.cpp b/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.operations/find.pass.cpp
new file mode 100644
index 0000000000000..74b7051eb0d7b
--- /dev/null
+++ b/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.operations/find.pass.cpp
@@ -0,0 +1,57 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+// UNSUPPORTED: c++03, c++11, c++14, c++17, c++20
+
+// <flat_map>
+
+// class flat_multimap
+
+// iterator find(const key_type& k);
+// const_iterator find(const key_type& k) const;
+
+#include <cassert>
+#include <deque>
+#include <flat_map>
+#include <functional>
+#include <string>
+#include <utility>
+
+#include "MinSequenceContainer.h"
+#include "test_macros.h"
+#include "min_allocator.h"
+
+template <class KeyContainer, class ValueContainer>
+void test() {
+ using Key = typename KeyContainer::value_type;
+ using Value = typename ValueContainer::value_type;
+ using M = std::flat_multimap<Key, Value, std::less<Key>, KeyContainer, ValueContainer>;
+
+ M m = {{1, 'a'}, {1, 'a'}, {1, 'b'}, {2, 'c'}, {2, 'b'}, {4, 'a'}, {4, 'd'}, {5, 'e'}, {8, 'a'}, {8, 'h'}};
+ ASSERT_SAME_TYPE(decltype(m.find(0)), typename M::iterator);
+ ASSERT_SAME_TYPE(decltype(std::as_const(m).find(0)), typename M::const_iterator);
+ assert(m.find(0) == m.end());
+ assert(m.find(1) == m.begin());
+ assert(m.find(2) == m.begin() + 3);
+ assert(m.find(3) == m.end());
+ assert(m.find(4) == m.begin() + 5);
+ assert(m.find(5) == m.begin() + 7);
+ assert(m.find(6) == m.end());
+ assert(m.find(7) == m.end());
+ assert(std::as_const(m).find(8) == m.begin() + 8);
+ assert(std::as_const(m).find(9) == m.end());
+}
+
+int main(int, char**) {
+ test<std::vector<int>, std::vector<char>>();
+ test<std::deque<int>, std::vector<char>>();
+ test<MinSequenceContainer<int>, MinSequenceContainer<char>>();
+ test<std::vector<int, min_allocator<int>>, std::vector<char, min_allocator<char>>>();
+
+ return 0;
+}
diff --git a/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.operations/find_transparent.pass.cpp b/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.operations/find_transparent.pass.cpp
new file mode 100644
index 0000000000000..be8c6f2e35440
--- /dev/null
+++ b/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.operations/find_transparent.pass.cpp
@@ -0,0 +1,99 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+// UNSUPPORTED: c++03, c++11, c++14, c++17, c++20
+
+// <flat_map>
+
+// class flat_multimap
+
+// template<class K> iterator find(const K& x);
+// template<class K> const_iterator find(const K& x) const;
+
+#include <cassert>
+#include <deque>
+#include <flat_map>
+#include <string>
+#include <utility>
+
+#include "MinSequenceContainer.h"
+#include "../helpers.h"
+#include "test_macros.h"
+#include "min_allocator.h"
+
+// Constraints: The qualified-id Compare::is_transparent is valid and denotes a type.
+template <class M>
+concept CanFind = requires(M m, Transparent<int> k) { m.find(k); };
+using TransparentMap = std::flat_multimap<int, double, TransparentComparator>;
+using NonTransparentMap = std::flat_multimap<int, double, NonTransparentComparator>;
+static_assert(CanFind<TransparentMap>);
+static_assert(CanFind<const TransparentMap>);
+static_assert(!CanFind<NonTransparentMap>);
+static_assert(!CanFind<const NonTransparentMap>);
+
+template <class KeyContainer, class ValueContainer>
+void test() {
+ using Key = typename KeyContainer::value_type;
+ using Value = typename ValueContainer::value_type;
+ using M = std::flat_multimap<Key, Value, TransparentComparator, KeyContainer, ValueContainer>;
+
+ M m = {{"alpha", 1},
+ {"beta", 2},
+ {"beta", 0},
+ {"beta", 1},
+ {"beta", 2},
+ {"epsilon", 3},
+ {"epsilon", 1},
+ {"eta", 4},
+ {"gamma", 6},
+ {"gamma", 5}};
+ const auto& cm = m;
+ ASSERT_SAME_TYPE(decltype(m.find(Transparent<std::string>{"abc"})), typename M::iterator);
+ ASSERT_SAME_TYPE(decltype(std::as_const(m).find(Transparent<std::string>{"b"})), typename M::const_iterator);
+
+ auto test_find = [&](auto&& map, const std::string& expected_key, long expected_offset) {
+ auto iter = map.find(Transparent<std::string>{expected_key});
+ assert(iter - map.begin() == expected_offset);
+ };
+
+ test_find(m, "alpha", 0);
+ test_find(m, "beta", 1);
+ test_find(m, "epsilon", 5);
+ test_find(m, "eta", 7);
+ test_find(m, "gamma", 8);
+ test_find(m, "charlie", 10);
+ test_find(m, "aaa", 10);
+ test_find(m, "zzz", 10);
+ test_find(cm, "alpha", 0);
+ test_find(cm, "beta", 1);
+ test_find(cm, "epsilon", 5);
+ test_find(cm, "eta", 7);
+ test_find(cm, "gamma", 8);
+ test_find(cm, "charlie", 10);
+ test_find(cm, "aaa", 10);
+ test_find(cm, "zzz", 10);
+}
+
+int main(int, char**) {
+ test<std::vector<std::string>, std::vector<int>>();
+ test<std::deque<std::string>, std::vector<int>>();
+ test<MinSequenceContainer<std::string>, MinSequenceContainer<int>>();
+ test<std::vector<std::string, min_allocator<std::string>>, std::vector<int, min_allocator<int>>>();
+
+ {
+ bool transparent_used = false;
+ TransparentComparator c(transparent_used);
+ std::flat_multimap<int, int, TransparentComparator> m(std::sorted_equivalent, {{1, 1}, {2, 2}, {3, 3}, {3, 3}}, c);
+ assert(!transparent_used);
+ auto it = m.find(Transparent<int>{3});
+ assert(it != m.end());
+ assert(transparent_used);
+ }
+
+ return 0;
+}
diff --git a/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.operations/lower_bound.pass.cpp b/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.operations/lower_bound.pass.cpp
new file mode 100644
index 0000000000000..c3befdda7de6e
--- /dev/null
+++ b/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.operations/lower_bound.pass.cpp
@@ -0,0 +1,73 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+// UNSUPPORTED: c++03, c++11, c++14, c++17, c++20
+
+// <flat_map>
+
+// class flat_multimap
+
+// iterator lower_bound(const key_type& k);
+// const_iterator lower_bound(const key_type& k) const;
+
+#include <cassert>
+#include <deque>
+#include <flat_map>
+#include <functional>
+#include <utility>
+
+#include "MinSequenceContainer.h"
+#include "test_macros.h"
+#include "min_allocator.h"
+
+template <class KeyContainer, class ValueContainer>
+void test() {
+ using Key = typename KeyContainer::value_type;
+ using Value = typename ValueContainer::value_type;
+ {
+ using M = std::flat_multimap<Key, Value, std::less<Key>, KeyContainer, ValueContainer>;
+ M m = {{1, 'a'}, {2, 'a'}, {2, 'c'}, {2, 'b'}, {4, 'd'}, {5, 'a'}, {5, 'e'}, {8, 'h'}, {8, 'a'}};
+ ASSERT_SAME_TYPE(decltype(m.lower_bound(0)), typename M::iterator);
+ ASSERT_SAME_TYPE(decltype(std::as_const(m).lower_bound(0)), typename M::const_iterator);
+ assert(m.lower_bound(0) == m.begin());
+ assert(m.lower_bound(1) == m.begin());
+ assert(m.lower_bound(2) == m.begin() + 1);
+ assert(m.lower_bound(3) == m.begin() + 4);
+ assert(m.lower_bound(4) == m.begin() + 4);
+ assert(m.lower_bound(5) == m.begin() + 5);
+ assert(m.lower_bound(6) == m.begin() + 7);
+ assert(m.lower_bound(7) == m.begin() + 7);
+ assert(std::as_const(m).lower_bound(8) == m.begin() + 7);
+ assert(std::as_const(m).lower_bound(9) == m.end());
+ }
+ {
+ using M = std::flat_multimap<Key, Value, std::greater<Key>, KeyContainer, ValueContainer>;
+ M m = {{1, 'a'}, {1, 'b'}, {2, 'b'}, {4, 'd'}, {4, 'a'}, {4, 'e'}, {5, 'e'}, {8, 'a'}, {8, 'h'}};
+ ASSERT_SAME_TYPE(decltype(m.lower_bound(0)), typename M::iterator);
+ ASSERT_SAME_TYPE(decltype(std::as_const(m).lower_bound(0)), typename M::const_iterator);
+ assert(m.lower_bound(0) == m.end());
+ assert(m.lower_bound(1) == m.begin() + 7);
+ assert(m.lower_bound(2) == m.begin() + 6);
+ assert(m.lower_bound(3) == m.begin() + 6);
+ assert(m.lower_bound(4) == m.begin() + 3);
+ assert(m.lower_bound(5) == m.begin() + 2);
+ assert(m.lower_bound(6) == m.begin() + 2);
+ assert(m.lower_bound(7) == m.begin() + 2);
+ assert(std::as_const(m).lower_bound(8) == m.begin());
+ assert(std::as_const(m).lower_bound(9) == m.begin());
+ }
+}
+
+int main(int, char**) {
+ test<std::vector<int>, std::vector<char>>();
+ test<std::deque<int>, std::vector<char>>();
+ test<MinSequenceContainer<int>, MinSequenceContainer<char>>();
+ test<std::vector<int, min_allocator<int>>, std::vector<char, min_allocator<char>>>();
+
+ return 0;
+}
diff --git a/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.operations/lower_bound_transparent.pass.cpp b/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.operations/lower_bound_transparent.pass.cpp
new file mode 100644
index 0000000000000..b757af132e677
--- /dev/null
+++ b/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.operations/lower_bound_transparent.pass.cpp
@@ -0,0 +1,107 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+// UNSUPPORTED: c++03, c++11, c++14, c++17, c++20
+
+// <flat_map>
+
+// class flat_multimap
+
+// template<class K> iterator lower_bound(const K& x);
+// template<class K> const_iterator lower_bound(const K& x) const;
+
+#include <cassert>
+#include <deque>
+#include <flat_map>
+#include <string>
+#include <utility>
+
+#include "MinSequenceContainer.h"
+#include "../helpers.h"
+#include "test_macros.h"
+#include "min_allocator.h"
+
+// Constraints: The qualified-id Compare::is_transparent is valid and denotes a type.
+template <class M>
+concept CanLowerBound = requires(M m, Transparent<int> k) { m.lower_bound(k); };
+using TransparentMap = std::flat_multimap<int, double, TransparentComparator>;
+using NonTransparentMap = std::flat_multimap<int, double, NonTransparentComparator>;
+static_assert(CanLowerBound<TransparentMap>);
+static_assert(CanLowerBound<const TransparentMap>);
+static_assert(!CanLowerBound<NonTransparentMap>);
+static_assert(!CanLowerBound<const NonTransparentMap>);
+
+template <class KeyContainer, class ValueContainer>
+void test() {
+ using Key = typename KeyContainer::value_type;
+ using Value = typename ValueContainer::value_type;
+ using M = std::flat_multimap<Key, Value, TransparentComparator, KeyContainer, ValueContainer>;
+
+ M m = {{"alpha", 1},
+ {"alpha", 2},
+ {"alpha", 3},
+ {"beta", 2},
+ {"epsilon", 3},
+ {"epsilon", 4},
+ {"eta", 4},
+ {"gamma", 5},
+ {"gamma", 5},
+ {"gamma", 5},
+ {"gamma", 5}};
+ const auto& cm = m;
+ ASSERT_SAME_TYPE(decltype(m.lower_bound(Transparent<std::string>{"abc"})), typename M::iterator);
+ ASSERT_SAME_TYPE(decltype(std::as_const(m).lower_bound(Transparent<std::string>{"b"})), typename M::const_iterator);
+
+ auto test_lower_bound = [&](auto&& map, const std::string& expected_key, long expected_offset) {
+ auto iter = map.lower_bound(Transparent<std::string>{expected_key});
+ assert(iter - map.begin() == expected_offset);
+ };
+
+ test_lower_bound(m, "abc", 0);
+ test_lower_bound(m, "alpha", 0);
+ test_lower_bound(m, "beta", 3);
+ test_lower_bound(m, "bets", 4);
+ test_lower_bound(m, "charlie", 4);
+ test_lower_bound(m, "echo", 4);
+ test_lower_bound(m, "epsilon", 4);
+ test_lower_bound(m, "eta", 6);
+ test_lower_bound(m, "gamma", 7);
+ test_lower_bound(m, "golf", 11);
+ test_lower_bound(m, "zzz", 11);
+
+ test_lower_bound(cm, "abc", 0);
+ test_lower_bound(cm, "alpha", 0);
+ test_lower_bound(cm, "beta", 3);
+ test_lower_bound(cm, "bets", 4);
+ test_lower_bound(cm, "charlie", 4);
+ test_lower_bound(cm, "echo", 4);
+ test_lower_bound(cm, "epsilon", 4);
+ test_lower_bound(cm, "eta", 6);
+ test_lower_bound(cm, "gamma", 7);
+ test_lower_bound(cm, "golf", 11);
+ test_lower_bound(cm, "zzz", 11);
+}
+
+int main(int, char**) {
+ test<std::vector<std::string>, std::vector<int>>();
+ test<std::deque<std::string>, std::vector<int>>();
+ test<MinSequenceContainer<std::string>, MinSequenceContainer<int>>();
+ test<std::vector<std::string, min_allocator<std::string>>, std::vector<int, min_allocator<int>>>();
+
+ {
+ bool transparent_used = false;
+ TransparentComparator c(transparent_used);
+ std::flat_multimap<int, int, TransparentComparator> m(std::sorted_equivalent, {{1, 1}, {2, 2}, {3, 3}}, c);
+ assert(!transparent_used);
+ auto it = m.lower_bound(Transparent<int>{3});
+ assert(it != m.end());
+ assert(transparent_used);
+ }
+
+ return 0;
+}
diff --git a/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.operations/upper_bound.pass.cpp b/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.operations/upper_bound.pass.cpp
new file mode 100644
index 0000000000000..d73d030236e22
--- /dev/null
+++ b/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.operations/upper_bound.pass.cpp
@@ -0,0 +1,76 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+// UNSUPPORTED: c++03, c++11, c++14, c++17, c++20
+
+// <flat_map>
+
+// class flat_multimap
+
+// iterator upper_bound(const key_type& k);
+// const_iterator upper_bound(const key_type& k) const;
+
+#include <cassert>
+#include <deque>
+#include <flat_map>
+#include <functional>
+#include <utility>
+
+#include "MinSequenceContainer.h"
+#include "test_macros.h"
+#include "min_allocator.h"
+
+template <class KeyContainer, class ValueContainer>
+void test() {
+ using Key = typename KeyContainer::value_type;
+ using Value = typename ValueContainer::value_type;
+ {
+ using M = std::flat_multimap<Key, Value, std::less<Key>, KeyContainer, ValueContainer>;
+ M m = {
+ {1, 'a'}, {2, 'b'}, {4, 'd'}, {4, 'e'}, {4, 'a'}, {4, 'b'}, {5, 'e'}, {5, 'a'}, {8, 'a'}, {8, 'b'}, {8, 'h'}};
+ ASSERT_SAME_TYPE(decltype(m.upper_bound(0)), typename M::iterator);
+ ASSERT_SAME_TYPE(decltype(std::as_const(m).upper_bound(0)), typename M::const_iterator);
+ assert(m.upper_bound(0) == m.begin());
+ assert(m.upper_bound(1) == m.begin() + 1);
+ assert(m.upper_bound(2) == m.begin() + 2);
+ assert(m.upper_bound(3) == m.begin() + 2);
+ assert(m.upper_bound(4) == m.begin() + 6);
+ assert(m.upper_bound(5) == m.begin() + 8);
+ assert(m.upper_bound(6) == m.begin() + 8);
+ assert(std::as_const(m).upper_bound(7) == m.begin() + 8);
+ assert(std::as_const(m).upper_bound(8) == m.end());
+ assert(std::as_const(m).upper_bound(9) == m.end());
+ }
+
+ {
+ using M = std::flat_multimap<Key, Value, std::greater<Key>, KeyContainer, ValueContainer>;
+ M m = {
+ {1, 'a'}, {2, 'b'}, {4, 'd'}, {4, 'e'}, {4, 'a'}, {4, 'b'}, {5, 'e'}, {5, 'a'}, {8, 'a'}, {8, 'b'}, {8, 'h'}};
+ ASSERT_SAME_TYPE(decltype(m.upper_bound(0)), typename M::iterator);
+ ASSERT_SAME_TYPE(decltype(std::as_const(m).upper_bound(0)), typename M::const_iterator);
+ assert(m.upper_bound(0) == m.end());
+ assert(m.upper_bound(1) == m.end());
+ assert(m.upper_bound(2) == m.begin() + 10);
+ assert(m.upper_bound(3) == m.begin() + 9);
+ assert(m.upper_bound(4) == m.begin() + 9);
+ assert(m.upper_bound(5) == m.begin() + 5);
+ assert(m.upper_bound(6) == m.begin() + 3);
+ assert(m.upper_bound(7) == m.begin() + 3);
+ assert(std::as_const(m).upper_bound(8) == m.begin() + 3);
+ assert(std::as_const(m).upper_bound(9) == m.begin());
+ }
+}
+
+int main(int, char**) {
+ test<std::vector<int>, std::vector<char>>();
+ test<std::deque<int>, std::vector<char>>();
+ test<MinSequenceContainer<int>, MinSequenceContainer<char>>();
+ test<std::vector<int, min_allocator<int>>, std::vector<char, min_allocator<char>>>();
+
+ return 0;
+}
diff --git a/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.operations/upper_bound_transparent.pass.cpp b/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.operations/upper_bound_transparent.pass.cpp
new file mode 100644
index 0000000000000..969489d0fe619
--- /dev/null
+++ b/libcxx/test/std/containers/container.adaptors/flat.multimap/flat.multimap.operations/upper_bound_transparent.pass.cpp
@@ -0,0 +1,106 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+// UNSUPPORTED: c++03, c++11, c++14, c++17, c++20
+
+// <flat_map>
+
+// class flat_multimap
+
+// template<class K> iterator upper_bound(const K& x);
+// template<class K> const_iterator upper_bound(const K& x) const;
+
+#include <cassert>
+#include <deque>
+#include <flat_map>
+#include <string>
+#include <utility>
+
+#include "MinSequenceContainer.h"
+#include "../helpers.h"
+#include "test_macros.h"
+#include "min_allocator.h"
+
+// Constraints: The qualified-id Compare::is_transparent is valid and denotes a type.
+template <class M>
+concept CanUpperBound = requires(M m, Transparent<int> k) { m.upper_bound(k); };
+using TransparentMap = std::flat_multimap<int, double, TransparentComparator>;
+using NonTransparentMap = std::flat_multimap<int, double, NonTransparentComparator>;
+static_assert(CanUpperBound<TransparentMap>);
+static_assert(CanUpperBound<const TransparentMap>);
+static_assert(!CanUpperBound<NonTransparentMap>);
+static_assert(!CanUpperBound<const NonTransparentMap>);
+
+template <class KeyContainer, class ValueContainer>
+void test() {
+ using Key = typename KeyContainer::value_type;
+ using Value = typename ValueContainer::value_type;
+ using M = std::flat_multimap<Key, Value, TransparentComparator, KeyContainer, ValueContainer>;
+
+ M m = {{"alpha", 1},
+ {"alpha", 2},
+ {"alpha", 3},
+ {"beta", 2},
+ {"epsilon", 3},
+ {"epsilon", 4},
+ {"eta", 4},
+ {"gamma", 5},
+ {"gamma", 5},
+ {"gamma", 5},
+ {"gamma", 5}};
+ const auto& cm = m;
+ ASSERT_SAME_TYPE(decltype(m.lower_bound(Transparent<std::string>{"abc"})), typename M::iterator);
+ ASSERT_SAME_TYPE(decltype(std::as_const(m).lower_bound(Transparent<std::string>{"b"})), typename M::const_iterator);
+
+ auto test_upper_bound = [&](auto&& map, const std::string& expected_key, long expected_offset) {
+ auto iter = map.upper_bound(Transparent<std::string>{expected_key});
+ assert(iter - map.begin() == expected_offset);
+ };
+
+ test_upper_bound(m, "abc", 0);
+ test_upper_bound(m, "alpha", 3);
+ test_upper_bound(m, "beta", 4);
+ test_upper_bound(m, "bets", 4);
+ test_upper_bound(m, "charlie", 4);
+ test_upper_bound(m, "echo", 4);
+ test_upper_bound(m, "epsilon", 6);
+ test_upper_bound(m, "eta", 7);
+ test_upper_bound(m, "gamma", 11);
+ test_upper_bound(m, "golf", 11);
+ test_upper_bound(m, "zzz", 11);
+
+ test_upper_bound(cm, "abc", 0);
+ test_upper_bound(cm, "alpha", 3);
+ test_upper_bound(cm, "beta", 4);
+ test_upper_bound(cm, "bets", 4);
+ test_upper_bound(cm, "charlie", 4);
+ test_upper_bound(cm, "echo", 4);
+ test_upper_bound(cm, "epsilon", 6);
+ test_upper_bound(cm, "eta", 7);
+ test_upper_bound(cm, "gamma", 11);
+ test_upper_bound(cm, "golf", 11);
+ test_upper_bound(cm, "zzz", 11);
+}
+
+int main(int, char**) {
+ test<std::vector<std::string>, std::vector<int>>();
+ test<std::deque<std::string>, std::vector<int>>();
+ test<MinSequenceContainer<std::string>, MinSequenceContainer<int>>();
+ test<std::vector<std::string, min_allocator<std::string>>, std::vector<int, min_allocator<int>>>();
+ {
+ bool transparent_used = false;
+ TransparentComparator c(transparent_used);
+ std::flat_multimap<int, int, TransparentComparator> m(std::sorted_equivalent, {{1, 1}, {2, 2}, {2, 2}, {3, 3}}, c);
+ assert(!transparent_used);
+ auto it = m.upper_bound(Transparent<int>{2});
+ assert(it == m.begin() + 3);
+ assert(transparent_used);
+ }
+
+ return 0;
+}
diff --git a/libcxx/test/std/containers/container.adaptors/flat.multimap/helpers.h b/libcxx/test/std/containers/container.adaptors/flat.multimap/helpers.h
new file mode 100644
index 0000000000000..252e2454d497c
--- /dev/null
+++ b/libcxx/test/std/containers/container.adaptors/flat.multimap/helpers.h
@@ -0,0 +1,389 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef SUPPORT_FLAT_MULTIMAP_HELPERS_H
+#define SUPPORT_FLAT_MULTIMAP_HELPERS_H
+
+#include <algorithm>
+#include <cassert>
+#include <string>
+#include <vector>
+#include <flat_map>
+
+#include "test_allocator.h"
+#include "test_macros.h"
+
+template <class... Args>
+void check_invariant(const std::flat_multimap<Args...>& m) {
+ assert(m.keys().size() == m.values().size());
+ const auto& keys = m.keys();
+ assert(std::is_sorted(keys.begin(), keys.end(), m.key_comp()));
+}
+
+struct StartsWith {
+ explicit StartsWith(char ch) : lower_(1, ch), upper_(1, ch + 1) {}
+ StartsWith(const StartsWith&) = delete;
+ void operator=(const StartsWith&) = delete;
+ struct Less {
+ using is_transparent = void;
+ bool operator()(const std::string& a, const std::string& b) const { return a < b; }
+ bool operator()(const StartsWith& a, const std::string& b) const { return a.upper_ <= b; }
+ bool operator()(const std::string& a, const StartsWith& b) const { return a < b.lower_; }
+ bool operator()(const StartsWith&, const StartsWith&) const {
+ assert(false); // should not be called
+ return false;
+ }
+ };
+
+private:
+ std::string lower_;
+ std::string upper_;
+};
+
+template <class T>
+struct CopyOnlyVector : std::vector<T> {
+ using std::vector<T>::vector;
+
+ CopyOnlyVector(const CopyOnlyVector&) = default;
+ CopyOnlyVector(CopyOnlyVector&& other) : CopyOnlyVector(other) {}
+ CopyOnlyVector(CopyOnlyVector&& other, std::vector<T>::allocator_type alloc) : CopyOnlyVector(other, alloc) {}
+
+ CopyOnlyVector& operator=(const CopyOnlyVector&) = default;
+ CopyOnlyVector& operator=(CopyOnlyVector& other) { return this->operator=(other); }
+};
+
+template <class T, bool ConvertibleToT = false>
+struct Transparent {
+ T t;
+
+ operator T() const
+ requires ConvertibleToT
+ {
+ return t;
+ }
+};
+
+template <class T>
+using ConvertibleTransparent = Transparent<T, true>;
+
+template <class T>
+using NonConvertibleTransparent = Transparent<T, false>;
+
+struct TransparentComparator {
+ using is_transparent = void;
+
+ bool* transparent_used = nullptr;
+ TransparentComparator() = default;
+ TransparentComparator(bool& used) : transparent_used(&used) {}
+
+ template <class T, bool Convertible>
+ bool operator()(const T& t, const Transparent<T, Convertible>& transparent) const {
+ if (transparent_used != nullptr) {
+ *transparent_used = true;
+ }
+ return t < transparent.t;
+ }
+
+ template <class T, bool Convertible>
+ bool operator()(const Transparent<T, Convertible>& transparent, const T& t) const {
+ if (transparent_used != nullptr) {
+ *transparent_used = true;
+ }
+ return transparent.t < t;
+ }
+
+ template <class T>
+ bool operator()(const T& t1, const T& t2) const {
+ return t1 < t2;
+ }
+};
+
+struct NonTransparentComparator {
+ template <class T, bool Convertible>
+ bool operator()(const T&, const Transparent<T, Convertible>&) const;
+
+ template <class T, bool Convertible>
+ bool operator()(const Transparent<T, Convertible>&, const T&) const;
+
+ template <class T>
+ bool operator()(const T&, const T&) const;
+};
+
+struct NoDefaultCtr {
+ NoDefaultCtr() = delete;
+};
+
+#ifndef TEST_HAS_NO_EXCEPTIONS
+template <class T>
+struct EmplaceUnsafeContainer : std::vector<T> {
+ using std::vector<T>::vector;
+
+ template <class... Args>
+ auto emplace(Args&&... args) -> decltype(std::declval<std::vector<T>>().emplace(std::forward<Args>(args)...)) {
+ if (this->size() > 1) {
+ auto it1 = this->begin();
+ auto it2 = it1 + 1;
+ // messing up the container
+ std::iter_swap(it1, it2);
+ }
+
+ throw 42;
+ }
+
+ template <class... Args>
+ auto insert(Args&&... args) -> decltype(std::declval<std::vector<T>>().insert(std::forward<Args>(args)...)) {
+ if (this->size() > 1) {
+ auto it1 = this->begin();
+ auto it2 = it1 + 1;
+ // messing up the container
+ std::iter_swap(it1, it2);
+ }
+
+ throw 42;
+ }
+};
+
+template <class T>
+struct ThrowOnEraseContainer : std::vector<T> {
+ using std::vector<T>::vector;
+
+ template <class... Args>
+ auto erase(Args&&... args) -> decltype(std::declval<std::vector<T>>().erase(std::forward<Args>(args)...)) {
+ throw 42;
+ }
+};
+
+template <class T>
+struct ThrowOnMoveContainer : std::vector<T> {
+ using std::vector<T>::vector;
+
+ ThrowOnMoveContainer(ThrowOnMoveContainer&&) { throw 42; }
+
+ ThrowOnMoveContainer& operator=(ThrowOnMoveContainer&&) { throw 42; }
+};
+
+#endif
+
+template <class F>
+void test_emplace_exception_guarantee([[maybe_unused]] F&& emplace_function) {
+#ifndef TEST_HAS_NO_EXCEPTIONS
+ using C = TransparentComparator;
+ {
+ // Throw on emplace the key, and underlying has strong exception guarantee
+ using KeyContainer = std::vector<int, test_allocator<int>>;
+ using M = std::flat_multimap<int, int, C, KeyContainer>;
+
+ LIBCPP_STATIC_ASSERT(std::__container_traits<KeyContainer>::__emplacement_has_strong_exception_safety_guarantee);
+
+ test_allocator_statistics stats;
+
+ KeyContainer a({1, 1, 2, 4}, test_allocator<int>{&stats});
+ std::vector<int> b = {5, 6, 7, 8};
+ [[maybe_unused]] auto expected_keys = a;
+ [[maybe_unused]] auto expected_values = b;
+ M m(std::sorted_equivalent, std::move(a), std::move(b));
+
+ stats.throw_after = 1;
+ try {
+ emplace_function(m, 1, 1);
+ assert(false);
+ } catch (const std::bad_alloc&) {
+ check_invariant(m);
+ // In libc++, the flat_multimap is unchanged
+ LIBCPP_ASSERT(m.size() == 4);
+ LIBCPP_ASSERT(m.keys() == expected_keys);
+ LIBCPP_ASSERT(m.values() == expected_values);
+ }
+ }
+ {
+ // Throw on emplace the key, and underlying has no strong exception guarantee
+ using KeyContainer = EmplaceUnsafeContainer<int>;
+ using M = std::flat_multimap<int, int, C, KeyContainer>;
+
+ LIBCPP_STATIC_ASSERT(!std::__container_traits<KeyContainer>::__emplacement_has_strong_exception_safety_guarantee);
+ KeyContainer a = {1, 2, 2, 4};
+ std::vector<int> b = {5, 6, 7, 8};
+ M m(std::sorted_equivalent, std::move(a), std::move(b));
+ try {
+ emplace_function(m, 1, 1);
+ assert(false);
+ } catch (int) {
+ check_invariant(m);
+ // In libc++, the flat_multimap is cleared
+ LIBCPP_ASSERT(m.size() == 0);
+ }
+ }
+ {
+ // Throw on emplace the value, and underlying has strong exception guarantee
+ using ValueContainer = std::vector<int, test_allocator<int>>;
+ ;
+ using M = std::flat_multimap<int, int, C, std::vector<int>, ValueContainer>;
+
+ LIBCPP_STATIC_ASSERT(std::__container_traits<ValueContainer>::__emplacement_has_strong_exception_safety_guarantee);
+
+ std::vector<int> a = {1, 3, 3, 4};
+ test_allocator_statistics stats;
+ ValueContainer b({1, 2, 3, 4}, test_allocator<int>{&stats});
+
+ [[maybe_unused]] auto expected_keys = a;
+ [[maybe_unused]] auto expected_values = b;
+ M m(std::sorted_equivalent, std::move(a), std::move(b));
+
+ stats.throw_after = 1;
+ try {
+ emplace_function(m, 3, 3);
+ assert(false);
+ } catch (const std::bad_alloc&) {
+ check_invariant(m);
+ // In libc++, the emplaced key is erased and the flat_multimap is unchanged
+ LIBCPP_ASSERT(m.size() == 4);
+ LIBCPP_ASSERT(m.keys() == expected_keys);
+ LIBCPP_ASSERT(m.values() == expected_values);
+ }
+ }
+ {
+ // Throw on emplace the value, and underlying has no strong exception guarantee
+ using ValueContainer = EmplaceUnsafeContainer<int>;
+ using M = std::flat_multimap<int, int, C, std::vector<int>, ValueContainer>;
+
+ LIBCPP_STATIC_ASSERT(!std::__container_traits<ValueContainer>::__emplacement_has_strong_exception_safety_guarantee);
+ std::vector<int> a = {1, 1, 1, 1};
+ ValueContainer b = {1, 2, 3, 4};
+
+ M m(std::sorted_equivalent, std::move(a), std::move(b));
+
+ try {
+ emplace_function(m, 1, 5);
+ assert(false);
+ } catch (int) {
+ check_invariant(m);
+ // In libc++, the flat_multimap is cleared
+ LIBCPP_ASSERT(m.size() == 0);
+ }
+ }
+ {
+ // Throw on emplace the value, then throw again on erasing the key
+ using KeyContainer = ThrowOnEraseContainer<int>;
+ using ValueContainer = std::vector<int, test_allocator<int>>;
+ using M = std::flat_multimap<int, int, C, KeyContainer, ValueContainer>;
+
+ LIBCPP_STATIC_ASSERT(std::__container_traits<ValueContainer>::__emplacement_has_strong_exception_safety_guarantee);
+
+ KeyContainer a = {4, 4, 4, 4};
+ test_allocator_statistics stats;
+ ValueContainer b({1, 2, 3, 4}, test_allocator<int>{&stats});
+
+ M m(std::sorted_equivalent, std::move(a), std::move(b));
+ stats.throw_after = 1;
+ try {
+ emplace_function(m, 0, 0);
+ assert(false);
+ } catch (const std::bad_alloc&) {
+ check_invariant(m);
+ // In libc++, we try to erase the key after value emplacement failure.
+ // and after erasure failure, we clear the flat_multimap
+ LIBCPP_ASSERT(m.size() == 0);
+ }
+ }
+#endif
+}
+
+template <class F>
+void test_insert_range_exception_guarantee([[maybe_unused]] F&& insert_function) {
+#ifndef TEST_HAS_NO_EXCEPTIONS
+ using KeyContainer = EmplaceUnsafeContainer<int>;
+ using ValueContainer = std::vector<int>;
+ using M = std::flat_multimap<int, int, std::ranges::less, KeyContainer, ValueContainer>;
+ test_allocator_statistics stats;
+ KeyContainer a{1, 2, 3, 4};
+ ValueContainer b{1, 2, 3, 4};
+ M m(std::sorted_equivalent, std::move(a), std::move(b));
+
+ std::vector<std::pair<int, int>> newValues = {{0, 0}, {1, 1}, {5, 5}, {6, 6}, {7, 7}, {8, 8}};
+ stats.throw_after = 1;
+ try {
+ insert_function(m, newValues);
+ assert(false);
+ } catch (int) {
+ check_invariant(m);
+ // In libc++, we clear if anything goes wrong when inserting a range
+ LIBCPP_ASSERT(m.size() == 0);
+ }
+#endif
+}
+
+template <class F>
+void test_erase_exception_guarantee([[maybe_unused]] F&& erase_function) {
+#ifndef TEST_HAS_NO_EXCEPTIONS
+ {
+ // key erase throws
+ using KeyContainer = ThrowOnEraseContainer<int>;
+ using ValueContainer = std::vector<int>;
+ using M = std::flat_multimap<int, int, TransparentComparator, KeyContainer, ValueContainer>;
+
+ KeyContainer a{1, 3, 3, 4};
+ ValueContainer b{1, 3, 3, 4};
+ M m(std::sorted_equivalent, std::move(a), std::move(b));
+ try {
+ erase_function(m, 3);
+ assert(false);
+ } catch (int) {
+ check_invariant(m);
+ // In libc++, we clear if anything goes wrong when erasing
+ LIBCPP_ASSERT(m.size() == 0);
+ }
+ }
+ {
+ // key erase throws
+ using KeyContainer = std::vector<int>;
+ using ValueContainer = ThrowOnEraseContainer<int>;
+ using M = std::flat_multimap<int, int, TransparentComparator, KeyContainer, ValueContainer>;
+
+ KeyContainer a{1, 3, 3, 4};
+ ValueContainer b{1, 3, 3, 4};
+ M m(std::sorted_equivalent, std::move(a), std::move(b));
+ try {
+ erase_function(m, 3);
+ assert(false);
+ } catch (int) {
+ check_invariant(m);
+ // In libc++, we clear if anything goes wrong when erasing
+ LIBCPP_ASSERT(m.size() == 0);
+ }
+ }
+#endif
+}
+class Moveable {
+ int int_;
+ double double_;
+
+public:
+ Moveable() : int_(0), double_(0) {}
+ Moveable(int i, double d) : int_(i), double_(d) {}
+ Moveable(Moveable&& x) : int_(x.int_), double_(x.double_) {
+ x.int_ = -1;
+ x.double_ = -1;
+ }
+ Moveable& operator=(Moveable&& x) {
+ int_ = x.int_;
+ x.int_ = -1;
+ double_ = x.double_;
+ x.double_ = -1;
+ return *this;
+ }
+
+ Moveable(const Moveable&) = delete;
+ Moveable& operator=(const Moveable&) = delete;
+ bool operator==(const Moveable& x) const { return int_ == x.int_ && double_ == x.double_; }
+ bool operator<(const Moveable& x) const { return int_ < x.int_ || (int_ == x.int_ && double_ < x.double_); }
+
+ int get() const { return int_; }
+ bool moved() const { return int_ == -1; }
+};
+
+#endif // SUPPORT_FLAT_MULTIMAP_HELPERS_H
diff --git a/libcxx/test/std/containers/container.adaptors/flat.multimap/incomplete_type.pass.cpp b/libcxx/test/std/containers/container.adaptors/flat.multimap/incomplete_type.pass.cpp
new file mode 100644
index 0000000000000..e4325b1dfe3ba
--- /dev/null
+++ b/libcxx/test/std/containers/container.adaptors/flat.multimap/incomplete_type.pass.cpp
@@ -0,0 +1,33 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+// UNSUPPORTED: c++03, c++11, c++14, c++17, c++20
+
+// <flat_map>
+
+// Check that std::flat_multimap and its iterators can be instantiated with an incomplete
+// type.
+
+#include <flat_map>
+#include <vector>
+
+struct A {
+ using Map = std::flat_multimap<A, A>;
+ int data;
+ Map m;
+ Map::iterator it;
+ Map::const_iterator cit;
+};
+
+// Implement the operator< required in order to instantiate flat_multimap<A, X>
+bool operator<(A const& L, A const& R) { return L.data < R.data; }
+
+int main(int, char**) {
+ A a;
+ return 0;
+}
diff --git a/libcxx/test/std/containers/container.adaptors/flat.multimap/op_compare.pass.cpp b/libcxx/test/std/containers/container.adaptors/flat.multimap/op_compare.pass.cpp
new file mode 100644
index 0000000000000..680ff1a127dda
--- /dev/null
+++ b/libcxx/test/std/containers/container.adaptors/flat.multimap/op_compare.pass.cpp
@@ -0,0 +1,133 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+// UNSUPPORTED: c++03, c++11, c++14, c++17, c++20
+
+// <flat_map>
+
+// class flat_multimap
+
+// friend bool operator==(const flat_multimap& x, const flat_multimap& y);
+// friend synth-three-way-result<value_type>
+// operator<=>(const flat_multimap& x, const flat_multimap& y);
+
+#include <algorithm>
+#include <cassert>
+#include <deque>
+#include <compare>
+#include <flat_map>
+#include <functional>
+#include <limits>
+#include <vector>
+
+#include "MinSequenceContainer.h"
+#include "test_macros.h"
+#include "min_allocator.h"
+#include "test_allocator.h"
+#include "test_comparisons.h"
+#include "test_container_comparisons.h"
+
+template <class KeyContainer, class ValueContainer>
+void test() {
+ using Key = typename KeyContainer::value_type;
+ using Value = typename ValueContainer::value_type;
+
+ {
+ using C = std::flat_multimap<Key, Value>;
+ C s1 = {{1, 1}};
+ C s2 = {{2, 0}}; // {{1,1}} versus {{2,0}}
+ ASSERT_SAME_TYPE(decltype(s1 <=> s2), std::strong_ordering);
+ AssertComparisonsReturnBool<C>();
+ assert(testComparisons(s1, s2, false, true));
+ s2 = {{1, 1}}; // {{1,1}} versus {{1,1}}
+ assert(testComparisons(s1, s2, true, false));
+ s2 = {{1, 1}, {2, 0}}; // {{1,1}} versus {{1,1},{2,0}}
+ assert(testComparisons(s1, s2, false, true));
+ s1 = {{0, 0}, {1, 1}, {2, 2}}; // {{0,0},{1,1},{2,2}} versus {{1,1},{2,0}}
+ assert(testComparisons(s1, s2, false, true));
+ s2 = {{0, 0}, {1, 1}, {2, 3}}; // {{0,0},{1,1},{2,2}} versus {{0,0},{1,1},{2,3}}
+ assert(testComparisons(s1, s2, false, true));
+
+ s1 = {{1, 1}, {1, 1}};
+ s2 = {{1, 1}, {1, 1}};
+ assert(testComparisons(s1, s2, true, false));
+
+ s2 = {{1, 1}, {1, 1}, {2, 2}};
+ assert(testComparisons(s1, s2, false, true));
+
+ s2 = {{1, 1}, {2, 2}, {2, 2}};
+ assert(testComparisons(s1, s2, false, true));
+
+ s2 = {{0, 0}, {1, 1}, {1, 1}};
+ assert(testComparisons(s1, s2, false, false));
+ }
+ {
+ // Comparisons use value_type's native operators, not the comparator
+ using C = std::flat_multimap<Key, Value, std::greater<Key>>;
+ C s1 = {{1, 1}};
+ C s2 = {{2, 0}}; // {{1,1}} versus {{2,0}}
+ ASSERT_SAME_TYPE(decltype(s1 <=> s2), std::strong_ordering);
+ AssertComparisonsReturnBool<C>();
+ assert(testComparisons(s1, s2, false, true));
+ s2 = {{1, 1}}; // {{1,1}} versus {{1,1}}
+ assert(testComparisons(s1, s2, true, false));
+ s2 = {{1, 1}, {2, 0}}; // {{1,1}} versus {{2,0},{1,1}}
+ assert(testComparisons(s1, s2, false, true));
+ s1 = {{0, 0}, {1, 1}, {2, 2}}; // {{2,2},{1,1},{0,0}} versus {2,0},{1,1}}
+ assert(testComparisons(s1, s2, false, false));
+ s2 = {{0, 0}, {1, 1}, {2, 3}}; // {{2,2},{1,1},{0,0}} versus {{2,3},{1,1},{0,0}}
+ assert(testComparisons(s1, s2, false, true));
+ }
+}
+
+int main(int, char**) {
+ test<std::vector<int>, std::vector<int>>();
+ test<std::deque<int>, std::deque<int>>();
+ test<MinSequenceContainer<int>, MinSequenceContainer<int>>();
+ test<std::vector<int, min_allocator<int>>, std::vector<int, min_allocator<int>>>();
+ test<std::vector<int, min_allocator<int>>, std::vector<int, min_allocator<int>>>();
+
+ {
+ using C = std::flat_multimap<double, int>;
+ C s1 = {{1, 1}};
+ C s2 = C(std::sorted_equivalent, {{std::numeric_limits<double>::quiet_NaN(), 2}});
+ ASSERT_SAME_TYPE(decltype(s1 <=> s2), std::partial_ordering);
+ AssertComparisonsReturnBool<C>();
+ assert(testComparisonsComplete(s1, s2, false, false, false));
+ }
+ {
+ using C = std::flat_multimap<int, double>;
+ C s1 = {{1, 1}};
+ C s2 = C(std::sorted_equivalent, {{2, std::numeric_limits<double>::quiet_NaN()}});
+ ASSERT_SAME_TYPE(decltype(s1 <=> s2), std::partial_ordering);
+ AssertComparisonsReturnBool<C>();
+ assert(testComparisonsComplete(s1, s2, false, true, false));
+ s2 = C(std::sorted_equivalent, {{1, std::numeric_limits<double>::quiet_NaN()}});
+ assert(testComparisonsComplete(s1, s2, false, false, false));
+ }
+ {
+ // Comparisons use value_type's native operators, not the comparator
+ struct StrongComp {
+ bool operator()(double a, double b) const { return std::strong_order(a, b) < 0; }
+ };
+ using C = std::flat_multimap<double, double, StrongComp>;
+ C s1 = {{1, 1}};
+ C s2 = {{std::numeric_limits<double>::quiet_NaN(), std::numeric_limits<double>::quiet_NaN()}};
+ ASSERT_SAME_TYPE(decltype(s1 <=> s2), std::partial_ordering);
+ AssertComparisonsReturnBool<C>();
+ assert(testComparisonsComplete(s1, s2, false, false, false));
+ s1 = {{{1, 1}, {std::numeric_limits<double>::quiet_NaN(), 1}}};
+ s2 = {{{std::numeric_limits<double>::quiet_NaN(), 1}, {1, 1}}};
+ assert(std::lexicographical_compare_three_way(
+ s1.keys().begin(), s1.keys().end(), s2.keys().begin(), s2.keys().end(), std::strong_order) ==
+ std::strong_ordering::equal);
+ assert(s1 != s2);
+ assert((s1 <=> s2) == std::partial_ordering::unordered);
+ }
+ return 0;
+}
diff --git a/libcxx/test/std/containers/container.adaptors/flat.multimap/types.compile.pass.cpp b/libcxx/test/std/containers/container.adaptors/flat.multimap/types.compile.pass.cpp
new file mode 100644
index 0000000000000..490d51c299793
--- /dev/null
+++ b/libcxx/test/std/containers/container.adaptors/flat.multimap/types.compile.pass.cpp
@@ -0,0 +1,133 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+// UNSUPPORTED: c++03, c++11, c++14, c++17, c++20
+
+// using key_type = Key;
+// using mapped_type = T;
+// using value_type = pair<key_type, mapped_type>;
+// using key_compare = Compare;
+// using reference = pair<const key_type&, mapped_type&>;
+// using const_reference = pair<const key_type&, const mapped_type&>;
+// using size_type = size_t;
+// using difference_type = ptrdiff_t;
+// using iterator = implementation-defined; // see [container.requirements]
+// using const_iterator = implementation-defined; // see [container.requirements]
+// using reverse_iterator = std::reverse_iterator<iterator>;
+// using const_reverse_iterator = std::reverse_iterator<const_iterator>;
+// using key_container_type = KeyContainer;
+// using mapped_container_type = MappedContainer;
+
+// class value_compare;
+
+// struct containers {
+// key_container_type keys;
+// mapped_container_type values;
+// };
+
+#include <concepts>
+#include <deque>
+#include <flat_map>
+#include <functional>
+#include <ranges>
+#include <string>
+#include <vector>
+#include "min_allocator.h"
+
+void test() {
+ {
+ using M = std::flat_multimap<int, double>;
+ static_assert(std::is_same_v<typename M::key_type, int>);
+ static_assert(std::is_same_v<typename M::mapped_type, double>);
+ static_assert(std::is_same_v<typename M::value_type, std::pair<int, double>>);
+ static_assert(std::is_same_v<typename M::key_compare, std::less<int>>);
+ static_assert(std::is_same_v<typename M::reference, std::pair<const int&, double&>>);
+ static_assert(std::is_same_v<typename M::const_reference, std::pair<const int&, const double&>>);
+ static_assert(std::is_same_v<typename M::size_type, size_t>);
+ static_assert(std::is_same_v<typename M::difference_type, ptrdiff_t>);
+ static_assert(requires { typename M::iterator; });
+ static_assert(requires { typename M::const_iterator; });
+ static_assert(std::is_same_v<typename M::reverse_iterator, std::reverse_iterator<typename M::iterator>>);
+ static_assert(
+ std::is_same_v<typename M::const_reverse_iterator, std::reverse_iterator<typename M::const_iterator>>);
+ static_assert(std::is_same_v<typename M::key_container_type, std::vector<int>>);
+ static_assert(std::is_same_v<typename M::mapped_container_type, std::vector<double>>);
+ static_assert(requires { typename M::value_compare; });
+ static_assert(requires { typename M::containers; });
+ static_assert(std::is_same_v<decltype(M::containers::keys), std::vector<int>>);
+ static_assert(std::is_same_v<decltype(M::containers::values), std::vector<double>>);
+ }
+
+ {
+ struct A {};
+ struct Compare {
+ bool operator()(const std::string&, const std::string&) const;
+ };
+ using M = std::flat_multimap<std::string, A, Compare, std::deque<std::string>, std::deque<A>>;
+ static_assert(std::is_same_v<typename M::key_type, std::string>);
+ static_assert(std::is_same_v<typename M::mapped_type, A>);
+ static_assert(std::is_same_v<typename M::value_type, std::pair<std::string, A>>);
+ static_assert(std::is_same_v<typename M::key_compare, Compare>);
+ static_assert(std::is_same_v<typename M::reference, std::pair<const std::string&, A&>>);
+ static_assert(std::is_same_v<typename M::const_reference, std::pair<const std::string&, const A&>>);
+ static_assert(std::is_same_v<typename M::size_type, size_t>);
+ static_assert(std::is_same_v<typename M::difference_type, ptrdiff_t>);
+ static_assert(requires { typename M::iterator; });
+ static_assert(requires { typename M::const_iterator; });
+ static_assert(std::is_same_v<typename M::reverse_iterator, std::reverse_iterator<typename M::iterator>>);
+ static_assert(
+ std::is_same_v<typename M::const_reverse_iterator, std::reverse_iterator<typename M::const_iterator>>);
+ static_assert(std::is_same_v<typename M::key_container_type, std::deque<std::string>>);
+ static_assert(std::is_same_v<typename M::mapped_container_type, std::deque<A>>);
+ static_assert(requires { typename M::value_compare; });
+ static_assert(requires { typename M::containers; });
+ static_assert(std::is_same_v<decltype(M::containers::keys), std::deque<std::string>>);
+ static_assert(std::is_same_v<decltype(M::containers::values), std::deque<A>>);
+ }
+ {
+ using C = std::flat_multimap<int, short>;
+ static_assert(std::is_same_v<C::key_type, int>);
+ static_assert(std::is_same_v<C::mapped_type, short>);
+ static_assert(std::is_same_v<C::value_type, std::pair<int, short>>);
+ static_assert(std::is_same_v<C::key_compare, std::less<int>>);
+ static_assert(!std::is_same_v<C::value_compare, std::less<int>>);
+ static_assert(std::is_same_v<C::reference, std::pair<const int&, short&>>);
+ static_assert(std::is_same_v<C::const_reference, std::pair<const int&, const short&>>);
+ static_assert(std::random_access_iterator<C::iterator>);
+ static_assert(std::random_access_iterator<C::const_iterator>);
+ static_assert(std::random_access_iterator<C::reverse_iterator>);
+ static_assert(std::random_access_iterator<C::const_reverse_iterator>);
+ static_assert(std::is_same_v<C::reverse_iterator, std::reverse_iterator<C::iterator>>);
+ static_assert(std::is_same_v<C::const_reverse_iterator, std::reverse_iterator<C::const_iterator>>);
+ static_assert(std::is_same_v<C::size_type, std::size_t>);
+ static_assert(std::is_same_v<C::difference_type, std::ptrdiff_t>);
+ static_assert(std::is_same_v<C::key_container_type, std::vector<int>>);
+ static_assert(std::is_same_v<C::mapped_container_type, std::vector<short>>);
+ }
+ {
+ using C = std::flat_multimap<short, int, std::greater<long>, std::deque<short, min_allocator<short>>>;
+ static_assert(std::is_same_v<C::key_type, short>);
+ static_assert(std::is_same_v<C::mapped_type, int>);
+ static_assert(std::is_same_v<C::value_type, std::pair<short, int>>);
+ static_assert(std::is_same_v<C::key_compare, std::greater<long>>);
+ static_assert(!std::is_same_v<C::value_compare, std::greater<long>>);
+ static_assert(std::is_same_v<C::reference, std::pair<const short&, int&>>);
+ static_assert(std::is_same_v<C::const_reference, std::pair<const short&, const int&>>);
+ static_assert(std::random_access_iterator<C::iterator>);
+ static_assert(std::random_access_iterator<C::const_iterator>);
+ static_assert(std::random_access_iterator<C::reverse_iterator>);
+ static_assert(std::random_access_iterator<C::const_reverse_iterator>);
+ static_assert(std::is_same_v<C::reverse_iterator, std::reverse_iterator<C::iterator>>);
+ static_assert(std::is_same_v<C::const_reverse_iterator, std::reverse_iterator<C::const_iterator>>);
+ // size_type is invariably size_t
+ static_assert(std::is_same_v<C::size_type, std::size_t>);
+ static_assert(std::is_same_v<C::difference_type, std::ptrdiff_t>);
+ static_assert(std::is_same_v<C::key_container_type, std::deque<short, min_allocator<short>>>);
+ static_assert(std::is_same_v<C::mapped_container_type, std::vector<int>>);
+ }
+}
diff --git a/libcxx/test/std/language.support/support.limits/support.limits.general/flat_map.version.compile.pass.cpp b/libcxx/test/std/language.support/support.limits/support.limits.general/flat_map.version.compile.pass.cpp
new file mode 100644
index 0000000000000..0add849312d5e
--- /dev/null
+++ b/libcxx/test/std/language.support/support.limits/support.limits.general/flat_map.version.compile.pass.cpp
@@ -0,0 +1,68 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+//
+// WARNING: This test was generated by generate_feature_test_macro_components.py
+// and should not be edited manually.
+//
+// clang-format off
+
+// <flat_map>
+
+// Test the feature test macros defined by <flat_map>
+
+/* Constant Value
+ __cpp_lib_flat_map 202207L [C++23]
+*/
+
+#include <flat_map>
+#include "test_macros.h"
+
+#if TEST_STD_VER < 14
+
+# ifdef __cpp_lib_flat_map
+# error "__cpp_lib_flat_map should not be defined before c++23"
+# endif
+
+#elif TEST_STD_VER == 14
+
+# ifdef __cpp_lib_flat_map
+# error "__cpp_lib_flat_map should not be defined before c++23"
+# endif
+
+#elif TEST_STD_VER == 17
+
+# ifdef __cpp_lib_flat_map
+# error "__cpp_lib_flat_map should not be defined before c++23"
+# endif
+
+#elif TEST_STD_VER == 20
+
+# ifdef __cpp_lib_flat_map
+# error "__cpp_lib_flat_map should not be defined before c++23"
+# endif
+
+#elif TEST_STD_VER == 23
+
+# ifndef __cpp_lib_flat_map
+# error "__cpp_lib_flat_map should be defined in c++23"
+# endif
+# if __cpp_lib_flat_map != 202207L
+# error "__cpp_lib_flat_map should have the value 202207L in c++23"
+# endif
+
+#elif TEST_STD_VER > 23
+
+# ifndef __cpp_lib_flat_map
+# error "__cpp_lib_flat_map should be defined in c++26"
+# endif
+# if __cpp_lib_flat_map != 202207L
+# error "__cpp_lib_flat_map should have the value 202207L in c++26"
+# endif
+
+#endif // TEST_STD_VER > 23
+
diff --git a/libcxx/test/std/language.support/support.limits/support.limits.general/version.version.compile.pass.cpp b/libcxx/test/std/language.support/support.limits/support.limits.general/version.version.compile.pass.cpp
index 7c03955df681d..2615820364478 100644
--- a/libcxx/test/std/language.support/support.limits/support.limits.general/version.version.compile.pass.cpp
+++ b/libcxx/test/std/language.support/support.limits/support.limits.general/version.version.compile.pass.cpp
@@ -88,6 +88,8 @@
201902L [C++20]
__cpp_lib_expected 202211L [C++23]
__cpp_lib_filesystem 201703L [C++17]
+ __cpp_lib_flat_map 202207L [C++23]
+ __cpp_lib_flat_set 202207L [C++23]
__cpp_lib_format 202110L [C++20]
__cpp_lib_format_path 202403L [C++26]
__cpp_lib_format_ranges 202207L [C++23]
@@ -528,6 +530,14 @@
# error "__cpp_lib_filesystem should not be defined before c++17"
# endif
+# ifdef __cpp_lib_flat_map
+# error "__cpp_lib_flat_map should not be defined before c++23"
+# endif
+
+# ifdef __cpp_lib_flat_set
+# error "__cpp_lib_flat_set should not be defined before c++23"
+# endif
+
# ifdef __cpp_lib_format
# error "__cpp_lib_format should not be defined before c++20"
# endif
@@ -1399,6 +1409,14 @@
# error "__cpp_lib_filesystem should not be defined before c++17"
# endif
+# ifdef __cpp_lib_flat_map
+# error "__cpp_lib_flat_map should not be defined before c++23"
+# endif
+
+# ifdef __cpp_lib_flat_set
+# error "__cpp_lib_flat_set should not be defined before c++23"
+# endif
+
# ifdef __cpp_lib_format
# error "__cpp_lib_format should not be defined before c++20"
# endif
@@ -2390,6 +2408,14 @@
# endif
# endif
+# ifdef __cpp_lib_flat_map
+# error "__cpp_lib_flat_map should not be defined before c++23"
+# endif
+
+# ifdef __cpp_lib_flat_set
+# error "__cpp_lib_flat_set should not be defined before c++23"
+# endif
+
# ifdef __cpp_lib_format
# error "__cpp_lib_format should not be defined before c++20"
# endif
@@ -3651,6 +3677,14 @@
# endif
# endif
+# ifdef __cpp_lib_flat_map
+# error "__cpp_lib_flat_map should not be defined before c++23"
+# endif
+
+# ifdef __cpp_lib_flat_set
+# error "__cpp_lib_flat_set should not be defined before c++23"
+# endif
+
# ifndef __cpp_lib_format
# error "__cpp_lib_format should be defined in c++20"
# endif
@@ -5092,6 +5126,26 @@
# endif
# endif
+# ifndef __cpp_lib_flat_map
+# error "__cpp_lib_flat_map should be defined in c++23"
+# endif
+# if __cpp_lib_flat_map != 202207L
+# error "__cpp_lib_flat_map should have the value 202207L in c++23"
+# endif
+
+# if !defined(_LIBCPP_VERSION)
+# ifndef __cpp_lib_flat_set
+# error "__cpp_lib_flat_set should be defined in c++23"
+# endif
+# if __cpp_lib_flat_set != 202207L
+# error "__cpp_lib_flat_set should have the value 202207L in c++23"
+# endif
+# else // _LIBCPP_VERSION
+# ifdef __cpp_lib_flat_set
+# error "__cpp_lib_flat_set should not be defined because it is unimplemented in libc++!"
+# endif
+# endif
+
# ifndef __cpp_lib_format
# error "__cpp_lib_format should be defined in c++23"
# endif
@@ -6779,6 +6833,26 @@
# endif
# endif
+# ifndef __cpp_lib_flat_map
+# error "__cpp_lib_flat_map should be defined in c++26"
+# endif
+# if __cpp_lib_flat_map != 202207L
+# error "__cpp_lib_flat_map should have the value 202207L in c++26"
+# endif
+
+# if !defined(_LIBCPP_VERSION)
+# ifndef __cpp_lib_flat_set
+# error "__cpp_lib_flat_set should be defined in c++26"
+# endif
+# if __cpp_lib_flat_set != 202207L
+# error "__cpp_lib_flat_set should have the value 202207L in c++26"
+# endif
+# else // _LIBCPP_VERSION
+# ifdef __cpp_lib_flat_set
+# error "__cpp_lib_flat_set should not be defined because it is unimplemented in libc++!"
+# endif
+# endif
+
# ifndef __cpp_lib_format
# error "__cpp_lib_format should be defined in c++26"
# endif
diff --git a/libcxx/utils/generate_feature_test_macro_components.py b/libcxx/utils/generate_feature_test_macro_components.py
index dae827f5de50c..20b656e08db43 100755
--- a/libcxx/utils/generate_feature_test_macro_components.py
+++ b/libcxx/utils/generate_feature_test_macro_components.py
@@ -505,6 +505,17 @@ def add_version_header(tc):
"test_suite_guard": "!defined(_LIBCPP_VERSION) || (_LIBCPP_HAS_FILESYSTEM && _LIBCPP_AVAILABILITY_HAS_FILESYSTEM_LIBRARY)",
"libcxx_guard": "_LIBCPP_HAS_FILESYSTEM && _LIBCPP_AVAILABILITY_HAS_FILESYSTEM_LIBRARY",
},
+ {
+ "name": "__cpp_lib_flat_map",
+ "values": {"c++23": 202207},
+ "headers": ["flat_map"],
+ },
+ {
+ "name": "__cpp_lib_flat_set",
+ "values": {"c++23": 202207},
+ "headers": ["flat_set"],
+ "unimplemented": True,
+ },
{
"name": "__cpp_lib_format",
"values": {