blob: 83f669de1fb25b91c56da29f5fc369ddcafcf9ae [file] [log] [blame]
* 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
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