// Copyright (c) 2017, 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.

class A {}

class B extends A {
  B operator +(int i) => this;
}

class C {
  B get property => new B();

  void set property(A value) {}
}

main() {
  new C().property += 1;
}