text: /**
   * @license
   * Copyright The Closure Library Authors.
   * SPDX-License-Identifier: Apache-2.0
   */
  
  goog.module('goog.dom.fullscreen_test');
  goog.setTestOnly();
  
  const DomHelper = goog.require('goog.dom.DomHelper');
  const PropertyReplacer = goog.require('goog.testing.PropertyReplacer');
  const asserts = goog.require('goog.testing.asserts');
  const fullscreen = goog.require('goog.dom.fullscreen');
  const testSuite = goog.require('goog.testing.testSuite');
  
  let domHelper;
  let mockDoc;
  let stubs;
  
  testSuite({
    setUp() {
      mockDoc = {};
      domHelper = new DomHelper();
      stubs = new PropertyReplacer();
      stubs.replace(domHelper, 'getDocument', () => mockDoc);
    },
  
    testGetFullScreenElement() {
      const element = document.createElement('div');
      mockDoc.fullscreenElement = element;
      assertEquals(element, fullscreen.getFullScreenElement(domHelper));
    },
  
    testGetFullScreenElementNotFullScreen() {
      assertNull(fullscreen.getFullScreenElement(domHelper));
    },
  });
  