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<!DOCTYPE HTML>
<meta charset=utf-8>
<title>Largest Contentful Paint:dynamically appended image with different
dimensions but same src triggers new entry.</title>
<body>
<script src="/resources/testharness.js"></script>
<script src="/resources/testharnessreport.js"></script>
<script src="resources/largest-contentful-paint-helpers.js"></script>
<img src='/images/black-rectangle.png' id='image_id' width="50" />
<script>
async_test(function (t) {
assert_implements(window.LargestContentfulPaint, "LargestContentfulPaint is not implemented");
let beforeLoad = performance.now();
let beforeSecondImageLoad = performance.now();
let firstCallback = true;
// black-rectangle.png is 50 x 25.
const original_rect_size = 50 * 25;
// The bigger black rectangle is 100 x 50, but defined with width="50".
const bigger_rect_size = 100 * 50;
const observer = new PerformanceObserver(
t.step_func(function (entryList) {
assert_equals(entryList.getEntries().length, 1);
const entry = entryList.getEntries()[0];
const url = window.location.origin + '/images/black-rectangle.png';
if (firstCallback) {
// Checks the original black rectangle.
// TODO(https://crbug.com/1411616): we're testing approximated values.
checkImage(entry, url, 'image_id', original_rect_size,
beforeLoad, ["approximateSize"]);
// Creates a new bigger black rectangle.
const img = document.createElement('img');
img.id = 'new_image_id';
img.src = url;
img.width = 100;
beforeSecondImageLoad = performance.now();
firstCallback = false;
document.body.appendChild(img);
} else {
// Checks the new black rectangle.
checkImage(entry, url, 'new_image_id', bigger_rect_size, beforeSecondImageLoad);
t.done();
}
})
);
observer.observe({ type: 'largest-contentful-paint', buffered: true });
}, 'Largest Contentful Paint:dynamically appended image with different ' +
'dimensions but same src triggers new entry.');
</script>
</body>
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