blob: e155c6625c3aea989e192106bd3adaaedb4c3a39 (
plain)
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
|
<!DOCTYPE html>
<html>
<meta name="viewport" content="width=device-width">
<script src="/resources/testharness.js"></script>
<script src="/resources/testharnessreport.js"></script>
<link rel="author" title="Mozilla" href="https://mozilla.org">
<link rel="help" href="https://drafts.csswg.org/css-scroll-anchoring/">
<link rel="help" href="https://bugzilla.mozilla.org/show_bug.cgi?id=1852818">
<style>
div {
height: 100vh;
}
</style>
<div></div>
<div id="anchor" style="height: 10px; background-color: blue;"></div>
<div></div>
<script>
promise_test(async t => {
assert_equals(window.scrollY, 0);
let anchorRect = anchor.getBoundingClientRect();
// Scroll to the anchor node.
window.scrollBy(0, anchorRect.y);
assert_equals(window.scrollY, anchorRect.y);
await new Promise(resolve => t.step_timeout(resolve, 0));
// Expand the first element so that scroll anchoring happens.
document.querySelectorAll("div")[0].style.height = "200vh";
// Flush the change.
document.querySelectorAll("div")[0].getBoundingClientRect();
await new Promise(resolve => window.addEventListener("scroll", resolve));
// Revert the height change in a scroll event handler.
document.querySelectorAll("div")[0].style.height = "";
await new Promise(resolve => requestAnimationFrame(resolve));
await new Promise(resolve => requestAnimationFrame(resolve));
assert_equals(window.scrollY, anchorRect.y);
}, "Scroll anchoring properly works after scrollable range shrinkage");
</script>
</html>
|
