| // Copyright (c) 2019, 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 The [==] operator in constant expressions was defined such that |
| /// [e1 != null] was only allowed if [e1] had one of the "primitive" system |
| /// types. Users had to rewrite their code to [!identical(e1, null)]. This was |
| /// changed so that the [==] expression is always allowed as long as one of the |
| /// operands is [null]. |
| /// @description Checks that [==] operator is allowed if one of the operands is |
| /// [null] in potentially constant or compile-time constant, and compile time |
| /// error is thrown if assertion fails. |
| /// @author iarkh@unipro.ru |
| |
| |
| const str1 = "test"; |
| const str2 = null; |
| |
| class MyClass { |
| final String? option; |
| const MyClass(String? str) : assert(str == null), this.option = "OK"; |
| } |
| |
| main() { |
| const MyClass c1 = MyClass("123"); |
| // ^ |
| // [analyzer] unspecified |
| // [cfe] unspecified |
| } |
