| // Copyright (c) 2022, 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 target property |
| /// T? target |
| /// The current object weakly referenced by this, if any. |
| /// |
| /// The value is either the object supplied in the constructor, or null if the |
| /// weak reference has been cleared. |
| /// |
| /// @description Check that the value of this property value is either the |
| /// object supplied in the constructor, or null if the weak reference has been |
| /// cleared |
| /// @author sgrekhov@unipro.ru |
| /// @issue 48391 |
| |
| import "../../gc_utils_lib.dart"; |
| import "../../../../Utils/expect.dart"; |
| |
| class C { |
| int id; |
| C(this.id); |
| |
| String toString() => "C($id)"; |
| } |
| |
| dynamic d; |
| |
| @pragma('vm:never-inline') |
| C? getNullObject() => null; |
| |
| @pragma('vm:never-inline') |
| WeakReference<C> createWeakReference() { |
| C? c = C(42); |
| d = c; |
| WeakReference<C> wr = WeakReference(c); |
| Expect.equals(c, wr.target); |
| c = getNullObject(); |
| Expect.isNull(c); |
| triggerGc(); |
| Expect.equals(d, wr.target); |
| return wr; |
| } |
| |
| main() { |
| WeakReference<C> wr = createWeakReference(); |
| triggerGc(); |
| Expect.equals("C(42)", wr.target.toString()); |
| d = getNullObject(); |
| Expect.isNull(d); |
| triggerGc(); |
| Expect.isNull(wr.target); |
| } |