| <!DOCTYPE HTML> |
| <meta charset=utf-8> |
| <title>Largest Contentful Paint: largest image is reported.</title> |
| <body> |
| <script src="/resources/testharness.js"></script> |
| <script src="/resources/testharnessreport.js"></script> |
| <script src="resources/largest-contentful-paint-helpers.js"></script> |
| <!-- There is some text and some images. We care about blue.png being reported, as it is the largest. --> |
| <p>This is some text! :)</p> |
| <img src='/images/red.png' id='red'/> |
| <img src='/images/blue.png' id='blue'/> |
| <img src='/images/black-rectangle.png' id='black'/> |
| <p>More text!</p> |
| <script> |
| async_test(function (t) { |
| assert_implements(window.LargestContentfulPaint, "LargestContentfulPaint is not implemented"); |
| const beforeLoad = performance.now(); |
| const observer = new PerformanceObserver( |
| t.step_func(entryList => { |
| entryList.getEntries().forEach(entry => { |
| // The text or other image could be reported as LCP if it is rendered before the blue image. |
| if (entry.id !== 'blue') |
| return; |
| |
| const url = window.location.origin + '/images/blue.png'; |
| // blue.png is 133 by 106. |
| const size = 133 * 106; |
| checkImage(entry, url, 'blue', size, beforeLoad); |
| t.done(); |
| }) |
| }) |
| ); |
| observer.observe({type: 'largest-contentful-paint', buffered: true}); |
| }, 'Largest Contentful Paint: largest image is reported.'); |
| </script> |
| </body> |
