LibTest/core/Expando/operator_square_brackets_A01_t06.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 T operator [](Object object)
 * Gets the value of this Expando's property on the given object. If the object
 * hasn't been expanded, the method returns null.
 * The object must not be a number, a string, a boolean or null.
 * @description Checks that this operator returns the value previously set for
 * the same argument.
 * @author rodionov
 */
import "../../../Utils/expect.dart";

class A {}

class B extends A {}

main() {
  var o1 = new Object();
  var o2 = new A();
  var o3 = new B();
  
  Expando exp = new Expando();

  exp[o1] = "o1";
  Expect.equals("o1", exp[o1]);
  Expect.isNull(exp[o2]);
  Expect.isNull(exp[o3]);
  
  exp[o2] = o2;
  Expect.equals("o1", exp[o1]);
  Expect.identical(o2, exp[o2]);
  Expect.isNull(exp[o3]);
  
  exp[o1] = "oo1";
  Expect.equals("oo1", exp[o1]);
  Expect.identical(o2, exp[o2]);
  Expect.isNull(exp[o3]);
  
  exp[o2] = null;
  exp[o3] = 1;
  Expect.equals("oo1", exp[o1]);
  Expect.isNull(exp[o2]);
  Expect.equals(1, exp[o3]);
}