| // 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 is now short-circuit in constant and potentially |
| /// constant expressions. It only attempts to evaluate the second operand if the |
| /// first operand evaluates to [true]. This makes [false && (null as |
| /// String).length] a valid constant expression. The second operand expression |
| /// still needs to be a potentially constant expression, which is a new use of |
| /// potentially constant expressions outside of [const] constructor initializer |
| /// lists. |
| /// @description Checks that [&&] does not attempt to calculate the second |
| /// operand of [&&] operation if the first one is [false] in the constant |
| /// expression. |
| /// @author iarkh@unipro.ru |
| |
| import "../../Utils/expect.dart"; |
| |
| const int i = 25; |
| const dynamic nil = null; |
| |
| class MyClass1 { |
| final bool b; |
| const MyClass1() : b = false && (null as String).length < 12; |
| } |
| |
| class MyClass2 { |
| final bool b; |
| const MyClass2() : b = false && nil; |
| } |
| |
| main() { |
| const bool a1 = (i < 0) && (null as String).length < 12; |
| Expect.isFalse(a1); |
| |
| const bool a2 = false && (null as String).length < 12; |
| Expect.isFalse(a2); |
| |
| const bool a3 = false && i < 12; |
| Expect.isFalse(a3); |
| |
| const bool a4 = false && i > 12; |
| Expect.isFalse(a4); |
| |
| const bool a5 = false && (nil + 1) > 10; |
| Expect.isFalse(a5); |
| |
| const MyClass1 c1 = MyClass1(); |
| Expect.isFalse(c1.b); |
| |
| const MyClass2 c2 = MyClass2(); |
| Expect.isFalse(c2.b); |
| } |