blob: 85e602c7674acfd7e2ed16b62e57997b6e564364 [file] [log] [blame]
// 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 result of [NNBD_TOP_MERGE] of [Object?] and
/// [void] is [Object?].
/// @Issue 40541,41576
/// @author
// Requirements=nnbd-strong
import "../../../Utils/expect.dart";
class B extends CheckTopMerge<Object?> {}
class C extends CheckTopMerge<void > {}
class D1 extends B implements C {}
class D2 extends C implements B {}
void main() {
Expect.isTrue(D1().f is Object? Function(Object?));
Expect.isTrue(D2().f is Object? Function(Object?));
Expect.runtimeIsType<Object? Function(Object?)>(D1().f);
Expect.runtimeIsType<Object? Function(Object?)>(D2().f);