diff --git a/compiler/rustc_hir_analysis/locales/en-US.ftl b/compiler/rustc_hir_analysis/locales/en-US.ftl
index aa56e60ec7539..f860809bcffec 100644
--- a/compiler/rustc_hir_analysis/locales/en-US.ftl
+++ b/compiler/rustc_hir_analysis/locales/en-US.ftl
@@ -62,14 +62,6 @@ hir_analysis_manual_implementation =
hir_analysis_substs_on_overridden_impl = could not resolve substs on overridden impl
-hir_analysis_unused_extern_crate =
- unused extern crate
- .suggestion = remove it
-
-hir_analysis_extern_crate_not_idiomatic =
- `extern crate` is not idiomatic in the new edition
- .suggestion = convert it to a `{$msg_code}`
-
hir_analysis_trait_object_declared_with_no_traits =
at least one trait is required for an object type
.alias_span = this alias does not contain a trait
diff --git a/compiler/rustc_hir_analysis/src/check_unused.rs b/compiler/rustc_hir_analysis/src/check_unused.rs
index 5716be4f1a954..f3f5851d8f92c 100644
--- a/compiler/rustc_hir_analysis/src/check_unused.rs
+++ b/compiler/rustc_hir_analysis/src/check_unused.rs
@@ -1,12 +1,8 @@
-use crate::errors::{ExternCrateNotIdiomatic, UnusedExternCrate};
-use rustc_data_structures::fx::FxHashMap;
use rustc_data_structures::unord::UnordSet;
-use rustc_hir as hir;
use rustc_hir::def::DefKind;
-use rustc_hir::def_id::{DefId, LocalDefId};
+use rustc_hir::def_id::LocalDefId;
use rustc_middle::ty::TyCtxt;
use rustc_session::lint;
-use rustc_span::{Span, Symbol};
pub fn check_crate(tcx: TyCtxt<'_>) {
let mut used_trait_imports: UnordSet<LocalDefId> = Default::default();
@@ -43,131 +39,4 @@ pub fn check_crate(tcx: TyCtxt<'_>) {
|lint| lint,
);
}
-
- unused_crates_lint(tcx);
-}
-
-fn unused_crates_lint(tcx: TyCtxt<'_>) {
- let lint = lint::builtin::UNUSED_EXTERN_CRATES;
-
- // Collect first the crates that are completely unused. These we
- // can always suggest removing (no matter which edition we are
- // in).
- let unused_extern_crates: FxHashMap<LocalDefId, Span> = tcx
- .maybe_unused_extern_crates(())
- .iter()
- .filter(|&&(def_id, _)| {
- tcx.extern_mod_stmt_cnum(def_id).map_or(true, |cnum| {
- !tcx.is_compiler_builtins(cnum)
- && !tcx.is_panic_runtime(cnum)
- && !tcx.has_global_allocator(cnum)
- && !tcx.has_panic_handler(cnum)
- })
- })
- .cloned()
- .collect();
-
- // Collect all the extern crates (in a reliable order).
- let mut crates_to_lint = vec![];
-
- for id in tcx.hir().items() {
- if matches!(tcx.def_kind(id.owner_id), DefKind::ExternCrate) {
- let item = tcx.hir().item(id);
- if let hir::ItemKind::ExternCrate(orig_name) = item.kind {
- crates_to_lint.push(ExternCrateToLint {
- def_id: item.owner_id.to_def_id(),
- span: item.span,
- orig_name,
- warn_if_unused: !item.ident.as_str().starts_with('_'),
- });
- }
- }
- }
-
- let extern_prelude = &tcx.resolutions(()).extern_prelude;
-
- for extern_crate in &crates_to_lint {
- let def_id = extern_crate.def_id.expect_local();
- let item = tcx.hir().expect_item(def_id);
-
- // If the crate is fully unused, we suggest removing it altogether.
- // We do this in any edition.
- if extern_crate.warn_if_unused {
- if let Some(&span) = unused_extern_crates.get(&def_id) {
- // Removal suggestion span needs to include attributes (Issue #54400)
- let id = tcx.hir().local_def_id_to_hir_id(def_id);
- let span_with_attrs = tcx
- .hir()
- .attrs(id)
- .iter()
- .map(|attr| attr.span)
- .fold(span, |acc, attr_span| acc.to(attr_span));
-
- tcx.emit_spanned_lint(lint, id, span, UnusedExternCrate { span: span_with_attrs });
- continue;
- }
- }
-
- // If we are not in Rust 2018 edition, then we don't make any further
- // suggestions.
- if !tcx.sess.rust_2018() {
- continue;
- }
-
- // If the extern crate isn't in the extern prelude,
- // there is no way it can be written as a `use`.
- let orig_name = extern_crate.orig_name.unwrap_or(item.ident.name);
- if !extern_prelude.get(&orig_name).map_or(false, |from_item| !from_item) {
- continue;
- }
-
- // If the extern crate is renamed, then we cannot suggest replacing it with a use as this
- // would not insert the new name into the prelude, where other imports in the crate may be
- // expecting it.
- if extern_crate.orig_name.is_some() {
- continue;
- }
-
- let id = tcx.hir().local_def_id_to_hir_id(def_id);
- // If the extern crate has any attributes, they may have funky
- // semantics we can't faithfully represent using `use` (most
- // notably `#[macro_use]`). Ignore it.
- if !tcx.hir().attrs(id).is_empty() {
- continue;
- }
-
- let base_replacement = match extern_crate.orig_name {
- Some(orig_name) => format!("use {} as {};", orig_name, item.ident.name),
- None => format!("use {};", item.ident.name),
- };
- let vis = tcx.sess.source_map().span_to_snippet(item.vis_span).unwrap_or_default();
- let add_vis = |to| if vis.is_empty() { to } else { format!("{} {}", vis, to) };
- tcx.emit_spanned_lint(
- lint,
- id,
- extern_crate.span,
- ExternCrateNotIdiomatic {
- span: extern_crate.span,
- msg_code: add_vis("use".to_string()),
- suggestion_code: add_vis(base_replacement),
- },
- );
- }
-}
-
-struct ExternCrateToLint {
- /// `DefId` of the extern crate
- def_id: DefId,
-
- /// span from the item
- span: Span,
-
- /// if `Some`, then this is renamed (`extern crate orig_name as
- /// crate_name`), and -- perhaps surprisingly -- this stores the
- /// *original* name (`item.name` will contain the new name)
- orig_name: Option<Symbol>,
-
- /// if `false`, the original name started with `_`, so we shouldn't lint
- /// about it going unused (but we should still emit idiom lints).
- warn_if_unused: bool,
}
diff --git a/compiler/rustc_hir_analysis/src/errors.rs b/compiler/rustc_hir_analysis/src/errors.rs
index be3ef03192c26..4da47866337c6 100644
--- a/compiler/rustc_hir_analysis/src/errors.rs
+++ b/compiler/rustc_hir_analysis/src/errors.rs
@@ -5,7 +5,7 @@ use rustc_errors::{
error_code, Applicability, DiagnosticBuilder, ErrorGuaranteed, Handler, IntoDiagnostic,
MultiSpan,
};
-use rustc_macros::{Diagnostic, LintDiagnostic};
+use rustc_macros::Diagnostic;
use rustc_middle::ty::Ty;
use rustc_span::{symbol::Ident, Span, Symbol};
@@ -247,26 +247,6 @@ pub struct SubstsOnOverriddenImpl {
pub span: Span,
}
-#[derive(LintDiagnostic)]
-#[diag(hir_analysis_unused_extern_crate)]
-pub struct UnusedExternCrate {
- #[suggestion(applicability = "machine-applicable", code = "")]
- pub span: Span,
-}
-
-#[derive(LintDiagnostic)]
-#[diag(hir_analysis_extern_crate_not_idiomatic)]
-pub struct ExternCrateNotIdiomatic {
- #[suggestion(
- style = "short",
- applicability = "machine-applicable",
- code = "{suggestion_code}"
- )]
- pub span: Span,
- pub msg_code: String,
- pub suggestion_code: String,
-}
-
#[derive(Diagnostic)]
#[diag(hir_analysis_const_impl_for_non_const_trait)]
pub struct ConstImplForNonConstTrait {
diff --git a/compiler/rustc_lint/src/context.rs b/compiler/rustc_lint/src/context.rs
index aace4974cc935..f5a711315ea4c 100644
--- a/compiler/rustc_lint/src/context.rs
+++ b/compiler/rustc_lint/src/context.rs
@@ -893,6 +893,23 @@ pub trait LintContext: Sized {
BuiltinLintDiagnostics::ByteSliceInPackedStructWithDerive => {
db.help("consider implementing the trait by hand, or remove the `packed` attribute");
}
+ BuiltinLintDiagnostics::UnusedExternCrate { removal_span }=> {
+ db.span_suggestion(
+ removal_span,
+ "remove it",
+ "",
+ Applicability::MachineApplicable,
+ );
+ }
+ BuiltinLintDiagnostics::ExternCrateNotIdiomatic { vis_span, ident_span }=> {
+ let suggestion_span = vis_span.between(ident_span);
+ db.span_suggestion_verbose(
+ suggestion_span,
+ "convert it to a `use`",
+ if vis_span.is_empty() { "use " } else { " use " },
+ Applicability::MachineApplicable,
+ );
+ }
}
// Rewrap `db`, and pass control to the user.
decorate(db)
diff --git a/compiler/rustc_lint_defs/src/lib.rs b/compiler/rustc_lint_defs/src/lib.rs
index 6efbf5ce9eef3..534aff7fb620f 100644
--- a/compiler/rustc_lint_defs/src/lib.rs
+++ b/compiler/rustc_lint_defs/src/lib.rs
@@ -522,6 +522,13 @@ pub enum BuiltinLintDiagnostics {
is_formatting_arg: bool,
},
ByteSliceInPackedStructWithDerive,
+ UnusedExternCrate {
+ removal_span: Span,
+ },
+ ExternCrateNotIdiomatic {
+ vis_span: Span,
+ ident_span: Span,
+ },
}
/// Lints that are buffered up early on in the `Session` before the
diff --git a/compiler/rustc_middle/src/query/mod.rs b/compiler/rustc_middle/src/query/mod.rs
index 6a34e5ede1938..0981ba83adf28 100644
--- a/compiler/rustc_middle/src/query/mod.rs
+++ b/compiler/rustc_middle/src/query/mod.rs
@@ -1830,9 +1830,6 @@ rustc_queries! {
query maybe_unused_trait_imports(_: ()) -> &'tcx FxIndexSet<LocalDefId> {
desc { "fetching potentially unused trait imports" }
}
- query maybe_unused_extern_crates(_: ()) -> &'tcx [(LocalDefId, Span)] {
- desc { "looking up all possibly unused extern crates" }
- }
query names_imported_by_glob_use(def_id: LocalDefId) -> &'tcx FxHashSet<Symbol> {
desc { |tcx| "finding names imported by glob use for `{}`", tcx.def_path_str(def_id.to_def_id()) }
}
diff --git a/compiler/rustc_middle/src/ty/context.rs b/compiler/rustc_middle/src/ty/context.rs
index 7e6a6e71670f3..e46a3416f570c 100644
--- a/compiler/rustc_middle/src/ty/context.rs
+++ b/compiler/rustc_middle/src/ty/context.rs
@@ -2504,8 +2504,6 @@ pub fn provide(providers: &mut ty::query::Providers) {
|tcx, id| tcx.resolutions(()).reexport_map.get(&id).map(|v| &v[..]);
providers.maybe_unused_trait_imports =
|tcx, ()| &tcx.resolutions(()).maybe_unused_trait_imports;
- providers.maybe_unused_extern_crates =
- |tcx, ()| &tcx.resolutions(()).maybe_unused_extern_crates[..];
providers.names_imported_by_glob_use = |tcx, id| {
tcx.arena.alloc(tcx.resolutions(()).glob_map.get(&id).cloned().unwrap_or_default())
};
diff --git a/compiler/rustc_middle/src/ty/mod.rs b/compiler/rustc_middle/src/ty/mod.rs
index f61fe707ac934..3995884f808cb 100644
--- a/compiler/rustc_middle/src/ty/mod.rs
+++ b/compiler/rustc_middle/src/ty/mod.rs
@@ -168,12 +168,8 @@ pub struct ResolverGlobalCtxt {
pub effective_visibilities: EffectiveVisibilities,
pub extern_crate_map: FxHashMap<LocalDefId, CrateNum>,
pub maybe_unused_trait_imports: FxIndexSet<LocalDefId>,
- pub maybe_unused_extern_crates: Vec<(LocalDefId, Span)>,
pub reexport_map: FxHashMap<LocalDefId, Vec<ModChild>>,
pub glob_map: FxHashMap<LocalDefId, FxHashSet<Symbol>>,
- /// Extern prelude entries. The value is `true` if the entry was introduced
- /// via `extern crate` item and not `--extern` option or compiler built-in.
- pub extern_prelude: FxHashMap<Symbol, bool>,
pub main_def: Option<MainDefinition>,
pub trait_impls: FxIndexMap<DefId, Vec<LocalDefId>>,
/// A list of proc macro LocalDefIds, written out in the order in which
diff --git a/compiler/rustc_resolve/src/check_unused.rs b/compiler/rustc_resolve/src/check_unused.rs
index 0114e116386b0..b2578e4c4b446 100644
--- a/compiler/rustc_resolve/src/check_unused.rs
+++ b/compiler/rustc_resolve/src/check_unused.rs
@@ -29,11 +29,12 @@ use crate::Resolver;
use rustc_ast as ast;
use rustc_ast::visit::{self, Visitor};
-use rustc_data_structures::fx::FxIndexMap;
+use rustc_data_structures::fx::{FxHashMap, FxIndexMap};
use rustc_data_structures::unord::UnordSet;
use rustc_errors::{pluralize, MultiSpan};
-use rustc_session::lint::builtin::{MACRO_USE_EXTERN_CRATE, UNUSED_IMPORTS};
+use rustc_session::lint::builtin::{MACRO_USE_EXTERN_CRATE, UNUSED_EXTERN_CRATES, UNUSED_IMPORTS};
use rustc_session::lint::BuiltinLintDiagnostics;
+use rustc_span::symbol::Ident;
use rustc_span::{Span, DUMMY_SP};
struct UnusedImport<'a> {
@@ -53,11 +54,28 @@ struct UnusedImportCheckVisitor<'a, 'b, 'tcx> {
r: &'a mut Resolver<'b, 'tcx>,
/// All the (so far) unused imports, grouped path list
unused_imports: FxIndexMap<ast::NodeId, UnusedImport<'a>>,
+ extern_crate_items: Vec<ExternCrateToLint>,
base_use_tree: Option<&'a ast::UseTree>,
base_id: ast::NodeId,
item_span: Span,
}
+struct ExternCrateToLint {
+ id: ast::NodeId,
+ /// Span from the item
+ span: Span,
+ /// Span to use to suggest complete removal.
+ span_with_attributes: Span,
+ /// Span of the visibility, if any.
+ vis_span: Span,
+ /// Whether the item has attrs.
+ has_attrs: bool,
+ /// Name used to refer to the crate.
+ ident: Ident,
+ /// Whether the statement renames the crate `extern crate orig_name as new_name;`.
+ renames: bool,
+}
+
impl<'a, 'b, 'tcx> UnusedImportCheckVisitor<'a, 'b, 'tcx> {
// We have information about whether `use` (import) items are actually
// used now. If an import is not used at all, we signal a lint error.
@@ -96,18 +114,27 @@ impl<'a, 'b, 'tcx> UnusedImportCheckVisitor<'a, 'b, 'tcx> {
impl<'a, 'b, 'tcx> Visitor<'a> for UnusedImportCheckVisitor<'a, 'b, 'tcx> {
fn visit_item(&mut self, item: &'a ast::Item) {
- self.item_span = item.span_with_attributes();
-
- // Ignore is_public import statements because there's no way to be sure
- // whether they're used or not. Also ignore imports with a dummy span
- // because this means that they were generated in some fashion by the
- // compiler and we don't need to consider them.
- if let ast::ItemKind::Use(..) = item.kind {
- if item.vis.kind.is_pub() || item.span.is_dummy() {
- return;
+ match item.kind {
+ // Ignore is_public import statements because there's no way to be sure
+ // whether they're used or not. Also ignore imports with a dummy span
+ // because this means that they were generated in some fashion by the
+ // compiler and we don't need to consider them.
+ ast::ItemKind::Use(..) if item.vis.kind.is_pub() || item.span.is_dummy() => return,
+ ast::ItemKind::ExternCrate(orig_name) => {
+ self.extern_crate_items.push(ExternCrateToLint {
+ id: item.id,
+ span: item.span,
+ vis_span: item.vis.span,
+ span_with_attributes: item.span_with_attributes(),
+ has_attrs: !item.attrs.is_empty(),
+ ident: item.ident,
+ renames: orig_name.is_some(),
+ });
}
+ _ => {}
}
+ self.item_span = item.span_with_attributes();
visit::walk_item(self, item);
}
@@ -224,6 +251,9 @@ fn calc_unused_spans(
impl Resolver<'_, '_> {
pub(crate) fn check_unused(&mut self, krate: &ast::Crate) {
+ let tcx = self.tcx;
+ let mut maybe_unused_extern_crates = FxHashMap::default();
+
for import in self.potentially_unused_imports.iter() {
match import.kind {
_ if import.used.get()
@@ -246,7 +276,14 @@ impl Resolver<'_, '_> {
}
ImportKind::ExternCrate { id, .. } => {
let def_id = self.local_def_id(id);
- self.maybe_unused_extern_crates.push((def_id, import.span));
+ if self.extern_crate_map.get(&def_id).map_or(true, |&cnum| {
+ !tcx.is_compiler_builtins(cnum)
+ && !tcx.is_panic_runtime(cnum)
+ && !tcx.has_global_allocator(cnum)
+ && !tcx.has_panic_handler(cnum)
+ }) {
+ maybe_unused_extern_crates.insert(id, import.span);
+ }
}
ImportKind::MacroUse => {
let msg = "unused `#[macro_use]` import";
@@ -259,6 +296,7 @@ impl Resolver<'_, '_> {
let mut visitor = UnusedImportCheckVisitor {
r: self,
unused_imports: Default::default(),
+ extern_crate_items: Default::default(),
base_use_tree: None,
base_id: ast::DUMMY_NODE_ID,
item_span: DUMMY_SP,
@@ -290,7 +328,7 @@ impl Resolver<'_, '_> {
let ms = MultiSpan::from_spans(spans.clone());
let mut span_snippets = spans
.iter()
- .filter_map(|s| match visitor.r.tcx.sess.source_map().span_to_snippet(*s) {
+ .filter_map(|s| match tcx.sess.source_map().span_to_snippet(*s) {
Ok(s) => Some(format!("`{}`", s)),
_ => None,
})
@@ -317,7 +355,7 @@ impl Resolver<'_, '_> {
// If we are in the `--test` mode, suppress a help that adds the `#[cfg(test)]`
// attribute; however, if not, suggest adding the attribute. There is no way to
// retrieve attributes here because we do not have a `TyCtxt` yet.
- let test_module_span = if visitor.r.tcx.sess.opts.test {
+ let test_module_span = if tcx.sess.opts.test {
None
} else {
let parent_module = visitor.r.get_nearest_non_block_module(
@@ -346,5 +384,74 @@ impl Resolver<'_, '_> {
BuiltinLintDiagnostics::UnusedImports(fix_msg.into(), fixes, test_module_span),
);
}
+
+ for extern_crate in visitor.extern_crate_items {
+ let warn_if_unused = !extern_crate.ident.name.as_str().starts_with('_');
+
+ // If the crate is fully unused, we suggest removing it altogether.
+ // We do this in any edition.
+ if warn_if_unused {
+ if let Some(&span) = maybe_unused_extern_crates.get(&extern_crate.id) {
+ visitor.r.lint_buffer.buffer_lint_with_diagnostic(
+ UNUSED_EXTERN_CRATES,
+ extern_crate.id,
+ span,
+ "unused extern crate",
+ BuiltinLintDiagnostics::UnusedExternCrate {
+ removal_span: extern_crate.span_with_attributes,
+ },
+ );
+ continue;
+ }
+ }
+
+ // If we are not in Rust 2018 edition, then we don't make any further
+ // suggestions.
+ if !tcx.sess.rust_2018() {
+ continue;
+ }
+
+ // If the extern crate has any attributes, they may have funky
+ // semantics we can't faithfully represent using `use` (most
+ // notably `#[macro_use]`). Ignore it.
+ if extern_crate.has_attrs {
+ continue;
+ }
+
+ // If the extern crate is renamed, then we cannot suggest replacing it with a use as this
+ // would not insert the new name into the prelude, where other imports in the crate may be
+ // expecting it.
+ if extern_crate.renames {
+ continue;
+ }
+
+ // If the extern crate isn't in the extern prelude,
+ // there is no way it can be written as a `use`.
+ if !visitor
+ .r
+ .extern_prelude
+ .get(&extern_crate.ident)
+ .map_or(false, |entry| !entry.introduced_by_item)
+ {
+ continue;
+ }
+
+ let vis_span = extern_crate
+ .vis_span
+ .find_ancestor_inside(extern_crate.span)
+ .unwrap_or(extern_crate.vis_span);
+ let ident_span = extern_crate
+ .ident
+ .span
+ .find_ancestor_inside(extern_crate.span)
+ .unwrap_or(extern_crate.ident.span);
+ visitor.r.lint_buffer.buffer_lint_with_diagnostic(
+ UNUSED_EXTERN_CRATES,
+ extern_crate.id,
+ extern_crate.span,
+ "`extern crate` is not idiomatic in the new edition",
+ BuiltinLintDiagnostics::ExternCrateNotIdiomatic { vis_span, ident_span },
+ );
+ }
}
}
diff --git a/compiler/rustc_resolve/src/lib.rs b/compiler/rustc_resolve/src/lib.rs
index 237ddd0f761f2..57c40a5b23e5b 100644
--- a/compiler/rustc_resolve/src/lib.rs
+++ b/compiler/rustc_resolve/src/lib.rs
@@ -946,7 +946,6 @@ pub struct Resolver<'a, 'tcx> {
has_pub_restricted: bool,
used_imports: FxHashSet<NodeId>,
maybe_unused_trait_imports: FxIndexSet<LocalDefId>,
- maybe_unused_extern_crates: Vec<(LocalDefId, Span)>,
/// Privacy errors are delayed until the end in order to deduplicate them.
privacy_errors: Vec<PrivacyError<'a>>,
@@ -1284,7 +1283,6 @@ impl<'a, 'tcx> Resolver<'a, 'tcx> {
has_pub_restricted: false,
used_imports: FxHashSet::default(),
maybe_unused_trait_imports: Default::default(),
- maybe_unused_extern_crates: Vec::new(),
privacy_errors: Vec::new(),
ambiguity_errors: Vec::new(),
@@ -1400,7 +1398,6 @@ impl<'a, 'tcx> Resolver<'a, 'tcx> {
let extern_crate_map = self.extern_crate_map;
let reexport_map = self.reexport_map;
let maybe_unused_trait_imports = self.maybe_unused_trait_imports;
- let maybe_unused_extern_crates = self.maybe_unused_extern_crates;
let glob_map = self.glob_map;
let main_def = self.main_def;
let confused_type_with_std_module = self.confused_type_with_std_module;
@@ -1414,12 +1411,6 @@ impl<'a, 'tcx> Resolver<'a, 'tcx> {
reexport_map,
glob_map,
maybe_unused_trait_imports,
- maybe_unused_extern_crates,
- extern_prelude: self
- .extern_prelude
- .iter()
- .map(|(ident, entry)| (ident.name, entry.introduced_by_item))
- .collect(),
main_def,
trait_impls: self.trait_impls,
proc_macros,
diff --git a/tests/ui/rust-2018/remove-extern-crate.fixed b/tests/ui/rust-2018/remove-extern-crate.fixed
index 832632268fb2e..15e0ccc5256a5 100644
--- a/tests/ui/rust-2018/remove-extern-crate.fixed
+++ b/tests/ui/rust-2018/remove-extern-crate.fixed
@@ -23,6 +23,7 @@ extern crate alloc;
fn main() {
another_name::mem::drop(3);
another::foo();
+ with_visibility::foo();
remove_extern_crate::foo!();
bar!();
alloc::vec![5];
@@ -37,3 +38,12 @@ mod another {
remove_extern_crate::foo!();
}
}
+
+mod with_visibility {
+ pub use core; //~ WARNING `extern crate` is not idiomatic
+
+ pub fn foo() {
+ core::mem::drop(4);
+ remove_extern_crate::foo!();
+ }
+}
diff --git a/tests/ui/rust-2018/remove-extern-crate.rs b/tests/ui/rust-2018/remove-extern-crate.rs
index bbb84cd462d7e..aec0bc7c37401 100644
--- a/tests/ui/rust-2018/remove-extern-crate.rs
+++ b/tests/ui/rust-2018/remove-extern-crate.rs
@@ -23,6 +23,7 @@ extern crate alloc;
fn main() {
another_name::mem::drop(3);
another::foo();
+ with_visibility::foo();
remove_extern_crate::foo!();
bar!();
alloc::vec![5];
@@ -37,3 +38,12 @@ mod another {
remove_extern_crate::foo!();
}
}
+
+mod with_visibility {
+ pub extern crate core; //~ WARNING `extern crate` is not idiomatic
+
+ pub fn foo() {
+ core::mem::drop(4);
+ remove_extern_crate::foo!();
+ }
+}
diff --git a/tests/ui/rust-2018/remove-extern-crate.stderr b/tests/ui/rust-2018/remove-extern-crate.stderr
index bde4c180811fa..d07358e471bb4 100644
--- a/tests/ui/rust-2018/remove-extern-crate.stderr
+++ b/tests/ui/rust-2018/remove-extern-crate.stderr
@@ -12,10 +12,26 @@ LL | #![warn(rust_2018_idioms)]
= note: `#[warn(unused_extern_crates)]` implied by `#[warn(rust_2018_idioms)]`
warning: `extern crate` is not idiomatic in the new edition
- --> $DIR/remove-extern-crate.rs:32:5
+ --> $DIR/remove-extern-crate.rs:33:5
|
LL | extern crate core;
- | ^^^^^^^^^^^^^^^^^^ help: convert it to a `use`
+ | ^^^^^^^^^^^^^^^^^^
+ |
+help: convert it to a `use`
+ |
+LL | use core;
+ | ~~~
+
+warning: `extern crate` is not idiomatic in the new edition
+ --> $DIR/remove-extern-crate.rs:43:5
+ |
+LL | pub extern crate core;
+ | ^^^^^^^^^^^^^^^^^^^^^^
+ |
+help: convert it to a `use`
+ |
+LL | pub use core;
+ | ~~~
-warning: 2 warnings emitted
+warning: 3 warnings emitted