HTMLLinkElement-load-event-002.html (2005B)
1 <!doctype html> 2 <meta charset="utf-8"> 3 <title>Link element load event doesn't block the parser.</title> 4 <link rel="author" title="Emilio Cobos Álvarez" href="mailto:emilio@crisal.io"> 5 <link rel="author" title="Mozilla" href="https://mozilla.org"> 6 <link rel="help" href="https://html.spec.whatwg.org/#link-type-stylesheet"> 7 <script src="/resources/testharness.js"></script> 8 <script src="/resources/testharnessreport.js"></script> 9 <script> 10 let NUM_LOADS = 0; 11 12 function sheetUrl(token) { 13 return "stylesheet-same-origin.css?" + token; 14 } 15 16 function createLink(token) { 17 let link = document.createElement("link"); 18 link.rel = "stylesheet"; 19 link.href = sheetUrl(token); 20 return link; 21 } 22 23 function waitForEnoughTimeToLoadSheet(token) { 24 return new Promise(resolve => { 25 let link = createLink(token); 26 link.onload = resolve; 27 document.head.appendChild(link); 28 }); 29 } 30 31 promise_test(async function (t) { 32 let link = createLink("removed"); 33 link.addEventListener("load", t.unreached_func("got unexpected load event")); 34 link.addEventListener("error", t.unreached_func("got unexpected error event")); 35 document.head.appendChild(link); 36 link.remove(); 37 38 await waitForEnoughTimeToLoadSheet("removed-wait"); 39 }, "Load event doesn't fire on removed link"); 40 41 promise_test(async function (t) { 42 let link = createLink("changed-initial"); 43 let sawLoad = false; 44 let load = new Promise(resolve => { 45 link.addEventListener("load", function(e) { 46 assert_false(sawLoad, "Should only see load event once"); 47 sawLoad = true; 48 resolve(); 49 }); 50 }); 51 link.addEventListener("error", t.unreached_func("got unexpected error event")); 52 document.head.appendChild(link); 53 link.href = sheetUrl("changed-change"); 54 55 await waitForEnoughTimeToLoadSheet("changed-wait"); 56 await load; 57 58 assert_true(sawLoad, "Should've seen the load event only once"); 59 }, "Load event doesn't fire for removed sheet"); 60 </script>