1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
|
<!DOCTYPE HTML>
<meta charset=utf-8>
<title>Element Timing: observe elements with the same resource</title>
<body>
<style>
body {
margin: 0;
}
</style>
<script src="/resources/testharness.js"></script>
<script src="/resources/testharnessreport.js"></script>
<script src="resources/element-timing-helpers.js"></script>
<script>
let beforeRender;
let numEntries = 0;
let loadTime1;
let loadTime2;
let renderTime1;
let renderTime2;
let img;
let img2;
async_test(function (t) {
assert_implements(window.PerformanceElementTiming, "PerformanceElementTiming is not implemented");
const observer = new PerformanceObserver(
t.step_func(function(entryList) {
assert_equals(entryList.getEntries().length, 1);
const entry = entryList.getEntries()[0];
const pathname = window.location.origin + '/element-timing/resources/square100.png';
// Easier to check the |element| attribute here since element ID is the same for both images.
checkElement(entry, pathname, entry.identifier, 'image_id', beforeRender, null);
checkNaturalSize(entry, 100, 100);
if (entry.identifier === 'my_image') {
++numEntries;
loadTime1 = entry.loadTime;
renderTime1 = entry.renderTime;
assert_equals(entry.element, img);
img2 = document.createElement('img');
img2.src = 'resources/square100.png';
img2.setAttribute('elementtiming', 'my_image2');
img2.setAttribute('id', 'image_id');
document.body.appendChild(img2);
beforeRender = performance.now();
}
else if (entry.identifier === 'my_image2') {
++numEntries;
loadTime2 = entry.loadTime;
renderTime2 = entry.renderTime;
assert_equals(entry.element, img2);
}
if (numEntries == 2) {
assert_greater_than(loadTime2, loadTime1, 'Second image loads after first.');
assert_greater_than(renderTime2, renderTime1, 'Second image renders after first');
t.done();
}
})
);
observer.observe({entryTypes: ['element']});
// We add the images 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 and height equal to 100.
img = document.createElement('img');
img.src = 'resources/square100.png';
img.setAttribute('elementtiming', 'my_image');
img.setAttribute('id', 'image_id');
document.body.appendChild(img);
beforeRender = performance.now();
};
}, 'Elements with elementtiming and same src are observable.');
</script>
</body>
|
