pkg/front_end/testcases/general/mix_in_enum.dart

// 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.md file.

class A {}

enum E { a, b }

class C = A with E;

main() {}