Source code

Revision control

Copy as Markdown

Other Tools

Test Info: Warnings

<!DOCTYPE html>
<title>Layout Instability: movement of descendant of sticky positioned</title>
<link rel="help" href="" />
<script src="/resources/testharness.js"></script>
<script src="/resources/testharnessreport.js"></script>
<script src="resources/util.js"></script>
<div style="position: sticky; width: 400px; height: 300px; top: 0">
<div id="child" style="position: relative; width: 300px; height: 200px; background: yellow"></div>
promise_test(async () => {
const watcher = new ScoreWatcher;
// Wait for the initial render to complete.
await waitForAnimationFrames(2);
// Modify the position of the div.
const child = document.querySelector("#child"); = '100px';
const expectedScore = computeExpectedScore(300 * (200 + 100), 100);
// Observer fires after the frame is painted.
assert_equals(watcher.score, 0);
await watcher.promise;
assert_equals(watcher.score, expectedScore);
}, 'Movement of descendant of sticky positioned.');