| // Copyright (c) 2020, 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 If a class [C] in an opted-in library implements the same generic |
| /// class [I] more than once as [I0], .., [In], and at least one of the [Ii] is |
| /// not syntactically equal to the others, then it is an error if |
| /// [NNBD_TOP_MERGE(S0, ..., Sn)] is not defined where [Si] is [NORM(Ii)]. |
| /// Otherwise, for the purposes of runtime subtyping checks, [C] is considered to |
| /// implement the canonical interface given by [NNBD_TOP_MERGE(S0, ..., Sn)]. |
| /// |
| /// @description Check that error occurs as a result of the following cases: |
| /// |
| /// [NNBD_TOP_MERGE(Never, FutureOr)]. |
| /// [NNBD_TOP_MERGE(Never, FutureOr<int>)]. |
| /// [NNBD_TOP_MERGE(Never, FutureOr<int?>)]. |
| /// [NNBD_TOP_MERGE(Never, FutureOr<FutureOr>)]. |
| /// |
| /// @author iarkh@unipro.ru |
| |
| |
| import "dart:async"; |
| |
| class A<T> {} |
| |
| class B implements A<Never> {} |
| |
| class C1 implements A<FutureOr> {} |
| class C2 implements A<FutureOr<int>> {} |
| class C3 implements A<FutureOr<int?>> {} |
| class C4 implements A<FutureOr<FutureOr>> {} |
| |
| class D1 extends B implements C1 {} |
| // ^^ |
| // [analyzer] unspecified |
| // [cfe] unspecified |
| |
| class D2 extends C1 implements B {} |
| // ^^ |
| // [analyzer] unspecified |
| // [cfe] unspecified |
| |
| class D3 extends B implements C2 {} |
| // ^^ |
| // [analyzer] unspecified |
| // [cfe] unspecified |
| |
| class D4 extends C2 implements B {} |
| // ^^ |
| // [analyzer] unspecified |
| // [cfe] unspecified |
| |
| class D5 extends B implements C3 {} |
| // ^^ |
| // [analyzer] unspecified |
| // [cfe] unspecified |
| |
| class D6 extends C3 implements B {} |
| // ^^ |
| // [analyzer] unspecified |
| // [cfe] unspecified |
| |
| class D7 extends B implements C4 {} |
| // ^^ |
| // [analyzer] unspecified |
| // [cfe] unspecified |
| |
| class D8 extends C4 implements B {} |
| // ^^ |
| // [analyzer] unspecified |
| // [cfe] unspecified |
| |
| void main() {} |