<!DOCTYPE HTML>
<html>
<head>
<meta charset="utf-8">
<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>
</head>
<body>
<main id=main>
<div>
<a id=link><img src="/images/lcp-256x256.png" id="img"></a>
</div>
</main>
<script>
const link = document.getElementById("link");
let first_lcp_painted;
let second_lcp_painted;
(async () => {
await new Promise(r => { first_lcp_painted = r; });
addImageToMain("lcp-133x106.png", "no_lcp");
(new PerformanceObserver(second_lcp_painted)).observe({type: "element"});
})();
testSoftNavigation({
pushState: null,
clicks: 2,
addContent: async () => {
// Add an LCP element.
await new Promise(resolve => {
addImageToMain("lcp-100x50.png", "first_lcp" + counter);
(new PerformanceObserver(resolve)).observe({type: "element"});
});
if(counter) {
first_lcp_painted();
// Wait for the unrelated LCP to be painted.
await new Promise(r => { second_lcp_painted = r; });
}
const url = URL + "?" + counter;
history.pushState({}, '', url);
},
link: link,
validate: async () => {
const lcps = await getLcpEntries();
const ref_counter = counter-1;
assert_equals(lcps.length, 2 + ref_counter, "Got 2 LCP entries");
assert_equals(lcps[lcps.length - 1].id, "first_lcp" + ref_counter,
"Got the first LCP");
},
test: "Second soft navigation image LCP discovered between user " +
"interaction and soft navigation detection are properly " +
"reported, while unrelated LCPs are ignored during that time. " +
"As a side effect, we also test element timing."});
</script>
</body>
</html>
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