mozilla-central/testing/web-platform/tests/soft-navigation-heuristics/softnav-after-lcp-paint.tentative.html

Source code

Revision control

Copy as Markdown

Other Tools

Test Info: Warnings

<!DOCTYPE HTML>
<html>
<head>
<meta charset="utf-8">
<title>Detect simple soft navigation.</title>
<script src="/resources/testharness.js"></script>
<script src="/resources/testharnessreport.js"></script>
<script src="/resources/testdriver.js"></script>
<script src="/resources/testdriver-vendor.js"></script>
<script src="resources/soft-navigation-helper.js"></script>
<link rel="stylesheet" type="text/css" href="/fonts/ahem.css" />
</head>
<body>
<main id=main>
<div>
<a id=link><img src="/images/lcp-256x256.png"></a>
</div>
</main>
<script>
const link = document.getElementById("link");
testSoftNavigation({
addContent: async () => {
let lcp_element_painted;
const lcp_element_paint_promise = new Promise((r) => { lcp_element_painted = r; });
// Add an LCP element, but have it be small enough to not trigger the
// Soft Navigation heuristics.
const p = addTextParagraphToMain("Lorem Ipsu", /*element_timing=*/"lcp");
(new PerformanceObserver(list => {
// Once the first element is fully painted:
lcp_element_painted();
})).observe({type: "element", buffered: true});
await lcp_element_paint_promise;
// Add a smaller element that gets us over that threshold.
addTextParagraphToMain("m");
},
link: link,
test: "Test that an image LCP followed by a smaller soft navigation LCP"
+ " properly queues an LCP entry, even when the soft navigation is"
+ " detected after the LCP."});
</script>
</body>
</html>