| /* |
| * 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 In a migrated library, override checking must check that an |
| * override is consistent with all overridden methods from other migrated |
| * libraries in the super-interface chain, since a legacy library is permitted |
| * to override otherwise incompatible signatures for a method. |
| * |
| * @description Check that if opted-in class implements two classes (one is |
| * legacy), child migrated method with [Never] return value cannot be called and |
| * compile error is thrown in this case. |
| * |
| * @author iarkh@unipro.ru |
| */ |
| // SharedOptions=--enable-experiment=non-nullable |
| |
| abstract class B { |
| Never test_return_never(); |
| } |
| |
| class A1 implements A { |
| Never test_return_never() => throw "It's impossible!"; |
| int? test_return_nullable() => 1; |
| } |
| |
| main() { |
| A1 a = A1(); |
| a.test_return_never(); |
| // ^^^^^^^^^^^^^^^^^ |
| // [analyzer] unspecified |
| // [cfe] unspecified |
| |
| } |
