| // 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. |
| |
| import "package:expect/expect.dart"; |
| |
| class A {} |
| |
| class B extends A { |
| static Object returnValue; |
| static Object argument; |
| Object operator +(Object x) { |
| argument = x; |
| return returnValue; |
| } |
| } |
| |
| void main() { |
| B origB = new B(); |
| B b = origB; |
| B.returnValue = new B(); |
| B.argument = null; |
| Expect.identical(B.returnValue, b += 2); // No error - types compatible |
| Expect.identical(B.returnValue, b); |
| Expect.identical(2, B.argument); |
| |
| b = origB; |
| B.returnValue = new A(); |
| B.argument = null; |
| Expect.throwsTypeError(() { |
| b += 3; |
| }); |
| // The exception should have happened after the call to operator+ but before |
| // the assignment to b. |
| Expect.identical(origB, b); |
| Expect.identical(3, B.argument); |
| |
| b = origB; |
| B.returnValue = new B(); |
| B.argument = null; |
| Expect.identical(B.returnValue, ++b); // No error - types compatible |
| Expect.identical(B.returnValue, b); |
| Expect.identical(1, B.argument); |
| |
| b = origB; |
| B.returnValue = new A(); |
| B.argument = null; |
| Expect.throwsTypeError(() { |
| ++b; |
| }); |
| // The exception should have happened after the call to operator+ but before |
| // the assignment to b. |
| Expect.identical(origB, b); |
| Expect.identical(1, B.argument); |
| |
| b = origB; |
| B.returnValue = new B(); |
| B.argument = null; |
| Expect.identical(origB, b++); // No error - types compatible |
| Expect.identical(B.returnValue, b); |
| Expect.identical(1, B.argument); |
| |
| b = origB; |
| B.returnValue = new A(); |
| B.argument = null; |
| Expect.throwsTypeError(() { |
| b++; |
| }); |
| // The exception should have happened after the call to operator+ but before |
| // the assignment to b. |
| Expect.identical(origB, b); |
| Expect.identical(1, B.argument); |
| } |