| <!DOCTYPE HTML> |
| <meta charset=utf-8> |
| <title>Largest Contentful Paint: observe image.</title> |
| <body> |
| <script src="/resources/testharness.js"></script> |
| <script src="/resources/testharnessreport.js"></script> |
| <script src="resources/largest-contentful-paint-helpers.js"></script> |
| <script> |
| async_test(function (t) { |
| assert_implements(window.LargestContentfulPaint, "LargestContentfulPaint is not implemented"); |
| const beforeLoad = performance.now(); |
| const observer = new PerformanceObserver( |
| t.step_func_done(function(entryList) { |
| assert_equals(entryList.getEntries().length, 1); |
| const entry = entryList.getEntries()[0]; |
| |
| const url = window.location.origin + '/images/blue.png'; |
| // blue.png is 133 by 106. |
| const size = 133 * 106; |
| checkImage(entry, url, 'image_id', size, beforeLoad); |
| }) |
| ); |
| observer.observe({type: 'largest-contentful-paint', buffered: true}); |
| }, 'Same-origin image after a JS initiated scroll event is observable.'); |
| document.body.dispatchEvent(new Event('scroll')); |
| const image = new Image(); |
| image.id = 'image_id'; |
| image.src = '/images/blue.png'; |
| document.body.appendChild(image); |
| </script> |
| |
| </body> |