| // 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 But switch statements must only be exhaustive when the matched |
| /// value is an always-exhaustive type, defined as: |
| /// - bool |
| /// - Null |
| /// - A enum type |
| /// - A type whose declaration is marked sealed |
| /// - T? where T is always-exhaustive |
| /// - FutureOr<T> for some type T that is always-exhaustive |
| /// - A record type whose fields all have always-exhaustive types |
| /// - A type variable X with bound T where T is always-exhaustive |
| /// - A promoted type variable X & T where T is always-exhaustive |
| /// |
| /// All other types are not always-exhaustive. Then: |
| /// - It is a compile-time error if the cases in a switch statement or switch |
| /// collection element are not exhaustive and the static type of the matched |
| /// value is an always-exhaustive type. There is no error if a switch |
| /// statement is not exhaustive when the type is not an always-exhaustive type |
| /// |
| /// @description Check that it is a compile-time error if a switch statement is |
| /// not exhaustive. Test a type `T?` where `T` is always-exhaustive |
| /// @author sgrekhov22@gmail.com |
| |
| main() { |
| bool? b = 1 > 2; |
| if (b) { |
| b = null; |
| } |
| switch (b) { |
| //^^^^^^ |
| // [analyzer] unspecified |
| // [cfe] unspecified |
| case true: |
| case false: |
| } |
| switch (b) { |
| //^^^^^^ |
| // [analyzer] unspecified |
| // [cfe] unspecified |
| case true: |
| case null: |
| } |
| } |
