| <!DOCTYPE HTML> |
| <meta charset=utf-8> |
| <title>Largest Contentful Paint: src change 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'/> |
| <script> |
| async_test(function (t) { |
| assert_implements(window.LargestContentfulPaint, "LargestContentfulPaint is not implemented"); |
| let beforeLoad = performance.now(); |
| let firstCallback = true; |
| 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 + (firstCallback ? '/images/black-rectangle.png' : '/images/blue.png'); |
| // black-rectangle.png is 100 x 50. blue.png is 133 by 106. |
| const size = firstCallback ? 100 * 50 : 133 * 106; |
| checkImage(entry, url, 'image_id', size, beforeLoad); |
| if (firstCallback) { |
| // Set the src to trigger another entry. |
| const img = document.getElementById('image_id'); |
| img.src = '/images/blue.png'; |
| beforeLoad = performance.now(); |
| firstCallback =false; |
| } else { |
| t.done(); |
| } |
| }) |
| ); |
| observer.observe({type: 'largest-contentful-paint', buffered: true}); |
| }, 'Largest Contentful Paint: changing src causes a new entry to be dispatched.'); |
| </script> |
| </body> |
