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
|
<!DOCTYPE html>
<head>
<title>In-viewport loading=lazy images do not block the window load event</title>
<link rel="author" title="Rob Buis" href="mailto:rbuis@igalia.com">
<link rel="author" title="Dom Farolino" href="mailto:dom@chromium.org">
<script src="/resources/testharness.js"></script>
<script src="/resources/testharnessreport.js"></script>
<script src="../resources/common.js"></script>
</head>
<body>
<!-- This image blocks the window load event for 1 second -->
<img src="resources/image.png?window-load-blocking&pipe=trickle(d1)">
<!-- These images must load because they intersect the viewport, but they must
not block the window load event, because they are loading=lazy -->
<img id="visible"
src="resources/image.png?visible&pipe=trickle(d3)" loading="lazy"
onload="visible_img.resolve();" onerror="visible_img.reject();">
<img id="visibility_hidden" style="visibility:hidden;"
src="resources/image.png?visibility_hidden&pipe=trickle(d3)" loading="lazy"
onload="visibility_hidden_img.resolve();" onerror="visibility_hidden_img.reject();">
</body>
<script>
const visible_img = new ElementLoadPromise("visible");
const visibility_hidden_img = new ElementLoadPromise("visibility_hidden");
async_test(t => {
let has_window_loaded = false;
window.addEventListener("load", t.step_func(() => {
has_window_loaded = true;
}));
Promise.all([visible_img.promise, visibility_hidden_img.promise])
.then(t.step_func_done(() => {
assert_true(has_window_loaded,
"The window load event should fire before the " +
"in-viewport loading=lazy images load");
assert_true(visible_img.element().complete,
"The in-viewport loading=lazy visible image is complete");
assert_true(visibility_hidden_img.element().complete,
"The in-viewport loading=lazy visibility:hidden image is " +
"complete");
}))
.catch(t.unreached_func("The images should load successfully"));
}, "In-viewport loading=lazy images do not block the window load event");
</script>
|
