// 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 Further, the interfaces B and C must be compatible. The on clause
/// introduces a synthetic interface combining B and C, call it A$super, which is
/// equivalent to the interface of a class declaration of the form:
///   abstract class A$super<X extends S, Y extends T> implements B, C {}
/// It is a compile-time error for the mixin declaration if the class declaration
/// above would not be valid.
///
/// @description Checks that it is a compile-time error for the mixin declaration
/// if the interfaces B and C are not compatible.
/// @author sgrekhov@unipro.ru


class S {}
class T {}
class X extends S {}
class Y extends T {}

class A<T> {
}
abstract class B<T> {
}
class C<T, S> implements A<T>, B<S> {
}

mixin M<X extends S, Y extends T> on A<Y>, B<X> {
}

class MA<X, Y> extends C<Y, X> with M<Y, X> {
//                                       ^
// [analyzer] unspecified
// [cfe] unspecified
}

main() {
  MA<X, Y> ma = new MA<X, Y>();
}