#2420. Add extension types exhaustiveness tests. Lists

LanguageFeatures/Extension-types/exhaustiveness_list_A01_t01.dart

@@ -0,0 +1,86 @@
+// Copyright (c) 2023, the Dart project authors.  Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
+/// @assertion A switch expression with `List` as the matched value type can be
+/// exhaustive, which can also make a switch expression with an extension type
+/// whose representation type is `List<...>` exhaustive.
+///
+/// @description Check that it is no compile-time error if a matched type of a
+/// switch expression is an extension type with a `List` as a representation
+/// type  and all cases are exhaustive. Test a rest element at the end of the
+/// list pattern
+/// @author [email protected]
+
+// SharedOptions=--enable-experiment=inline-class
+
+import "../../Utils/expect.dart";
+
+extension type ET1<T>(List<T> _) {}
+extension type ET2<T>(List<T> _) implements List<T> {}
+
+String test1_1(ET1<int> l) =>
+  switch (l) {
+    <int?>[] => "0",
+    [_] => "1",
+    [_, _] => "2",
+    [_, _, ...] => "2+"
+  };
+
+String test1_2(ET2<int> l) =>
+  switch (l) {
+    <int?>[] => "0",
+    [_] => "1",
+    [_, _] => "2",
+    [_, _, ...] => "2+"
+  };
+
+String test2_1(ET1<bool> l) =>
+  switch (l) {
+    [] => "0",
+    [true] => "1_1",
+    [false] => "1_2",
+    [_, true] => "2_1",
+    [_, false] => "2_2",
+    [_, true, ...var r1] => "3_1",
+    [_, false, ...final r2] => "3_2"
+  };
+
+String test2_2(ET2<bool> l) =>
+  switch (l) {
+    [] => "0",
+    [true] => "1_1",
+    [false] => "1_2",
+    [_, true] => "2_1",
+    [_, false] => "2_2",
+    [_, true, ...var r1] => "3_1",
+    [_, false, ...final r2] => "3_2"
+  };
+
+main() {
+  Expect.equals("0", test1_1(ET1([])));
+  Expect.equals("1", test1_1(ET1([1])));
+  Expect.equals("2", test1_1(ET1<int>([1, 2])));
+  Expect.equals("2+", test1_1(ET1([1, 2, 3])));
+
+  Expect.equals("0", test1_2(ET2([])));
+  Expect.equals("1", test1_2(ET2([1])));
+  Expect.equals("2", test1_2(ET2<int>([1, 2])));
+  Expect.equals("2+", test1_2(ET2([1, 2, 3])));
+
+  Expect.equals("0", test2_1(ET1([])));
+  Expect.equals("1_1", test2_1(ET1([true])));
+  Expect.equals("1_2", test2_1(ET1([false])));
+  Expect.equals("2_1", test2_1(ET1([true, true])));
+  Expect.equals("2_2", test2_1(ET1([true, false])));
+  Expect.equals("3_1", test2_1(ET1([true, true, false])));
+  Expect.equals("3_2", test2_1(ET1([true, false, false])));
+
+  Expect.equals("0", test2_2(ET2([])));
+  Expect.equals("1_1", test2_2(ET2([true])));
+  Expect.equals("1_2", test2_2(ET2([false])));
+  Expect.equals("2_1", test2_2(ET2([true, true])));
+  Expect.equals("2_2", test2_2(ET2([true, false])));
+  Expect.equals("3_1", test2_2(ET2([true, true, false])));
+  Expect.equals("3_2", test2_2(ET2([true, false, false])));
+}

LanguageFeatures/Extension-types/exhaustiveness_list_A01_t02.dart

@@ -0,0 +1,86 @@
+// Copyright (c) 2023, the Dart project authors.  Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
+/// @assertion A switch expression with `List` as the matched value type can be
+/// exhaustive, which can also make a switch expression with an extension type
+/// whose representation type is `List<...>` exhaustive.
+///
+/// @description Check that it is no compile-time error if a matched type of a
+/// switch expression is an extension type with a `List` as a representation
+/// type  and all cases are exhaustive. Test a rest element at the middle of the
+/// list pattern
+/// @author [email protected]
+
+// SharedOptions=--enable-experiment=inline-class
+
+import "../../Utils/expect.dart";
+
+extension type ET1<T>(List<T> _) {}
+extension type ET2<T>(List<T> _) implements List<T> {}
+
+String test1_1(ET1<int> l) =>
+  switch (l) {
+    [] => "0",
+    <int?>[_] => "1",
+    [_, _] => "2",
+    [_, ..., _] => "2+"
+  };
+
+String test1_2(ET2<int> l) =>
+  switch (l) {
+    [] => "0",
+    <int?>[_] => "1",
+    [_, _] => "2",
+    [_, ..., _] => "2+"
+  };
+
+String test2_1(ET1<bool> l) =>
+  switch (l) {
+    [] => "0",
+    [true] => "1_1",
+    [false] => "1_2",
+    [_, true] => "2_1",
+    [_, false] => "2_2",
+    [_, ... var r1, true] => "3_1",
+    [_, ... final r2, false] => "3_2"
+  };
+
+String test2_2(ET2<bool> l) =>
+  switch (l) {
+    [] => "0",
+    [true] => "1_1",
+    [false] => "1_2",
+    [_, true] => "2_1",
+    [_, false] => "2_2",
+    [_, ... var r1, true] => "3_1",
+    [_, ... final r2, false] => "3_2"
+  };
+
+main() {
+  Expect.equals("0", test1_1(ET1([])));
+  Expect.equals("1", test1_1(ET1([1])));
+  Expect.equals("2", test1_1(ET1<int>([1, 2])));
+  Expect.equals("2+", test1_1(ET1([1, 2, 3])));
+
+  Expect.equals("0", test1_2(ET2([])));
+  Expect.equals("1", test1_2(ET2([1])));
+  Expect.equals("2", test1_2(ET2<int>([1, 2])));
+  Expect.equals("2+", test1_2(ET2([1, 2, 3])));
+
+  Expect.equals("0", test2_1(ET1([])));
+  Expect.equals("1_1", test2_1(ET1([true])));
+  Expect.equals("1_2", test2_1(ET1([false])));
+  Expect.equals("2_1", test2_1(ET1([true, true])));
+  Expect.equals("2_2", test2_1(ET1([true, false])));
+  Expect.equals("3_1", test2_1(ET1([true, true, true])));
+  Expect.equals("3_2", test2_1(ET1([true, false, false])));
+
+  Expect.equals("0", test2_2(ET2([])));
+  Expect.equals("1_1", test2_2(ET2([true])));
+  Expect.equals("1_2", test2_2(ET2([false])));
+  Expect.equals("2_1", test2_2(ET2([true, true])));
+  Expect.equals("2_2", test2_2(ET2([true, false])));
+  Expect.equals("3_1", test2_2(ET2([true, true, true])));
+  Expect.equals("3_2", test2_2(ET2([true, false, false])));
+}

LanguageFeatures/Extension-types/exhaustiveness_list_A01_t03.dart

@@ -0,0 +1,86 @@
+// Copyright (c) 2023, the Dart project authors.  Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
+/// @assertion A switch expression with `List` as the matched value type can be
+/// exhaustive, which can also make a switch expression with an extension type
+/// whose representation type is `List<...>` exhaustive.
+///
+/// @description Check that it is no compile-time error if a matched type of a
+/// switch expression is an extension type with a `List` as a representation
+/// type  and all cases are exhaustive. Test rest element at the beginning of
+/// the list pattern
+/// @author [email protected]
+
+// SharedOptions=--enable-experiment=inline-class
+
+import "../../Utils/expect.dart";
+
+extension type ET1<T>(List<T> _) {}
+extension type ET2<T>(List<T> _) implements List<T> {}
+
+String test1_1(ET1<int> l) =>
+  switch (l) {
+    [] => "0",
+    [_] => "1",
+    [_, _] => "2",
+    <int?>[..., _, _] => "2+"
+  };
+
+String test1_2(ET2<int> l) =>
+  switch (l) {
+    [] => "0",
+    [_] => "1",
+    [_, _] => "2",
+    <int?>[..., _, _] => "2+"
+  };
+
+String test2_1(ET1<bool> l) =>
+  switch (l) {
+    [] => "0",
+    [true] => "1_1",
+    [false] => "1_2",
+    [_, true] => "2_1",
+    [_, false] => "2_2",
+    [... var r1, true] => "3_1",
+    [... final r2, false] => "3_2"
+  };
+
+String test2_2(ET2<bool> l) =>
+  switch (l) {
+    [] => "0",
+    [true] => "1_1",
+    [false] => "1_2",
+    [_, true] => "2_1",
+    [_, false] => "2_2",
+    [... var r1, true] => "3_1",
+    [... final r2, false] => "3_2"
+  };
+
+main() {
+  Expect.equals("0", test1_1(ET1([])));
+  Expect.equals("1", test1_1(ET1([1])));
+  Expect.equals("2", test1_1(ET1([1, 2])));
+  Expect.equals("2+", test1_1(ET1([1, 2, 3])));
+
+  Expect.equals("0", test1_2(ET2([])));
+  Expect.equals("1", test1_2(ET2([1])));
+  Expect.equals("2", test1_2(ET2([1, 2])));
+  Expect.equals("2+", test1_2(ET2([1, 2, 3])));
+
+  Expect.equals("0", test2_1(ET1([])));
+  Expect.equals("1_1", test2_1(ET1([true])));
+  Expect.equals("1_2", test2_1(ET1([false])));
+  Expect.equals("2_1", test2_1(ET1([true, true])));
+  Expect.equals("2_2", test2_1(ET1([true, false])));
+  Expect.equals("3_1", test2_1(ET1([true, true, true])));
+  Expect.equals("3_2", test2_1(ET1([true, false, false])));
+
+  Expect.equals("0", test2_2(ET2([])));
+  Expect.equals("1_1", test2_2(ET2([true])));
+  Expect.equals("1_2", test2_2(ET2([false])));
+  Expect.equals("2_1", test2_2(ET2([true, true])));
+  Expect.equals("2_2", test2_2(ET2([true, false])));
+  Expect.equals("3_1", test2_2(ET2([true, true, true])));
+  Expect.equals("3_2", test2_2(ET2([true, false, false])));
+}

LanguageFeatures/Extension-types/exhaustiveness_list_A02_t01.dart

@@ -0,0 +1,48 @@
+// Copyright (c) 2023, the Dart project authors.  Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
+/// @assertion Switch statements with a list as a matched type can never be
+/// exhaustive
+///
+/// @description Check that exhaustiveness check is not performed for a switch
+/// statement with a matched value type an extension type with the
+/// representation type`List`.
+/// @author [email protected]
+
+extension type ET1<T>(List<T> _) {}
+extension type ET2<T>(List<T> _) implements List<T> {}
+
+String test1(ET1<bool> l) {
+//     ^^^^^
+// [analyzer] unspecified
+// [cfe] unspecified
+  switch (l) {
+    case []:
+    case [_]:
+    case [_, _]:
+    case [_, _, ...]:
+      return "ok";
+  }
+// There is no return statement here, and static analysis doesn't know if the
+// switch statement exhaustive or not, so an error above occurs because function
+// return type cannot be null
+}
+
+String test2(ET2<bool> l) {
+//     ^^^^^
+// [analyzer] unspecified
+// [cfe] unspecified
+  switch (l) {
+    case []:
+    case [_]:
+    case [_, _]:
+    case [_, _, ...]:
+      return "ok";
+  }
+}
+
+main() {
+  test1(ET1([]));
+  test2(ET2([]));
+}