pkg/front_end/test/fasta/rasta/duplicated_mixin.dart

// Copyright (c) 2016, 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.md file.

class Mixin {
  var field;
}

class A extends Object with Mixin, Mixin {
}