chrome/test/data/extensions/api_test/events/background.js

// Copyright 2011 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

chrome.test.runTests([
  // Tests that attaching a named event twice will fail.
  function doubleAttach() {
    function dummy() {};
    const onClicked = new chrome.Event('browserAction.onClicked');
    const onClicked2 = new chrome.Event('browserAction.onClicked');
    onClicked.addListener(dummy);
    chrome.test.assertTrue(onClicked.hasListeners());
    try {
      onClicked2.addListener(dummy);
      chrome.test.fail();
    } catch (e) {
      chrome.test.assertTrue(
          e.message.search('already attached') >= 0,
          e.message);
    }
    chrome.test.assertFalse(onClicked2.hasListeners());
    onClicked2.removeListener(dummy);

    onClicked.removeListener(dummy);
    chrome.test.assertFalse(onClicked.hasListeners());
    chrome.test.succeed();
  },

  // Tests that 2 pages attaching to the same event does not trigger a DCHECK.
  function twoPageAttach() {
    // Test harness should already have opened tab.html, which registers this
    // listener.
    chrome.browserAction.onClicked.addListener(function() {});

    // Test continues in twoPageAttach.html.
    window.open('twoPageAttach.html');
  },
]);