41 lines
1.7 KiB
HTML
41 lines
1.7 KiB
HTML
<!DOCTYPE HTML>
|
|
<meta charset=utf-8>
|
|
<title>Element Timing: element attribute returns null when element is disconnected</title>
|
|
<body>
|
|
<script src="/resources/testharness.js"></script>
|
|
<script src="/resources/testharnessreport.js"></script>
|
|
<script src="resources/element-timing-helpers.js"></script>
|
|
<script>
|
|
let beforeRender;
|
|
let img;
|
|
async_test(function (t) {
|
|
assert_implements(window.PerformanceElementTiming, "PerformanceElementTiming is not implemented");
|
|
const observer = new PerformanceObserver(
|
|
t.step_func_done(function(entryList) {
|
|
assert_equals(entryList.getEntries().length, 1);
|
|
const entry = entryList.getEntries()[0];
|
|
const pathname = window.location.origin + '/element-timing/resources/square100.png';
|
|
// This method will check that entry.element is |img|.
|
|
checkElement(entry, pathname, 'my_image', 'my_id', beforeRender, img);
|
|
|
|
img.parentNode.removeChild(img);
|
|
// After removing image, entry.element should return null.
|
|
assert_equals(entry.element, null);
|
|
})
|
|
);
|
|
observer.observe({entryTypes: ['element']});
|
|
// We add the image during onload to be sure that the observer is registered
|
|
// in time for it to observe the element timing.
|
|
window.onload = () => {
|
|
// Add image of width equal to 100 and height equal to 100.
|
|
img = document.createElement('img');
|
|
img.src = 'resources/square100.png';
|
|
img.setAttribute('elementtiming', 'my_image');
|
|
img.setAttribute('id', 'my_id');
|
|
document.body.appendChild(img);
|
|
beforeRender = performance.now();
|
|
};
|
|
}, 'Disconnected elements have null as their |element| attribute.');
|
|
</script>
|
|
|
|
</body>
|