Language/12_Expressions/22_Equality_A02_t04.dart

/*
 * Copyright (c) 2011, 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.
 */
/**
 * @assertion Evaluation of an equality expression ee of the form e1 == e2 proceeds
 * as follows:
 * -  The expression e1 is evaluated to an object o1 .
 * -  The expression e2 is evaluated to an object o2 .
 * -  If either o1 or o2 is null, then ee evaluates to identical(o1 , o2 ).
 *    Otherwise, ee is equivalent to the method invocation o1 .==(o2 ).
 * @description Checks that if operands are not not [:null:]
 * ee is equivalent to the method invocation o1.==(o2).
 * @author msyabro
 * @reviewer iefremov
 */
import "../../Utils/expect.dart";

class TestException {}

class A {
  operator == (other) {
    throw new TestException();
  }
}

main() {
  A a = new A();
  try {
    a == 1;
    Expect.fail("operator== was not called");
  } on TestException catch(e) {}
}