chrome/browser/resources/chromeos/chromevox/testing/fake_objects.js

   1 // Copyright 2014 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 /**
   6  * Fakes a Chrome event that supports one listener.
   7  * @constructor
   8  * @extends {ChromeEvent}
   9  */
  10 function FakeChromeEvent() {
  11   /**
  12    * @private
  13    * @type {Function}
  14    */
  15   this.listener_ = null;
  16 }
  17
  18 FakeChromeEvent.prototype = {
  19   /**
  20    * Fakes the corresponding call on a Chrome event.  Sets the listener and
  21    * fails the test if it is already set.
  22    * @param {Function} listener The new listener.
  23    */
  24   addListener: function(listener) {
  25     this.assertNoListener();
  26     this.listener_ = listener;
  27   },
  28
  29   /**
  30    * Gets the listener of the event, failing the test if there's none.
  31    * @return {Function} The event's listener.
  32    */
  33   getListener: function() {
  34     assertNotEquals(null, this.listener_);
  35     return this.listener_;
  36   },
  37
  38   /**
  39    * Asserts that this object doesn't have any listener added.
  40    */
  41   assertNoListener: function() {
  42     assertEquals(null, this.listener_);
  43   }
  44 };