| <!DOCTYPE html> |
| <meta charset="utf-8"> |
| <title>beforeunload event is emitted synchronously</title> |
| <link rel="help" href="https://html.spec.whatwg.org/multipage/webappapis.html#the-event-handler-processing-algorithm"> |
| <script src="/resources/testharness.js"></script> |
| <script src="/resources/testharnessreport.js"></script> |
| <body> |
| <script> |
| 'use strict'; |
| // "navigate a browsing context" synchronously calls "prompt to unload", which |
| // synchronously calls "dispatch an event". |
| |
| async_test(function(t) { |
| var iframe = document.createElement('iframe'); |
| |
| iframe.onload = t.step_func(function() { |
| var callCount = 0; |
| |
| iframe.contentWindow.onbeforeunload = function() { |
| callCount += 1; |
| }; |
| |
| iframe.contentWindow.location.href = '/common/blank.html'; |
| |
| assert_equals(callCount, 1, 'invoked synchronously exactly once'); |
| |
| t.done(); |
| }); |
| |
| document.body.appendChild(iframe); |
| }); |
| </script> |
| </body> |
