| // Copyright (c) 2018, 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. |
| |
| // @dart = 2.9 |
| |
| /// @assertion In a mixin declaration like |
| /// mixin A<X extends S, Y extends T> on B, C implements D, E { body } |
| /// the on clause declares the interfaces B and C as super-class constraints of |
| /// the mixin. Having a super-class constaint allows the mixin declaration |
| /// instance members to perform super-invocations (like super.foo()) if they are |
| /// allowed by a class implementing both B and C. The mixin introduced by A can |
| /// then only be applied to classes that implement both B and C. |
| /// |
| /// @description Checks that it is not a compile but runtime error if mixin is |
| /// applied to the class which doesn't implement required interface |
| /// @author sgrekhov@unipro.ru |
| /// @issue 35111 |
| /// @issue 46361 |
| |
| import "../../Utils/expect.dart"; |
| |
| class A { |
| covariant num number; |
| } |
| |
| class B extends A { |
| int number; |
| } |
| |
| mixin M on A { |
| test() { |
| Expect.throws(() { |
| super.number = 3.14; |
| }); |
| } |
| } |
| |
| class MA extends B with M {} |
| |
| main() { |
| new MA().test(); |
| } |