observe-after-untrusted-scroll.html (1207B)
1 <!DOCTYPE HTML> 2 <meta charset=utf-8> 3 <title>Largest Contentful Paint: observe image.</title> 4 <body> 5 <script src="/resources/testharness.js"></script> 6 <script src="/resources/testharnessreport.js"></script> 7 <script src="resources/largest-contentful-paint-helpers.js"></script> 8 <script> 9 async_test(function (t) { 10 assert_implements(window.LargestContentfulPaint, "LargestContentfulPaint is not implemented"); 11 const beforeLoad = performance.now(); 12 const observer = new PerformanceObserver( 13 t.step_func_done(function(entryList) { 14 assert_equals(entryList.getEntries().length, 1); 15 const entry = entryList.getEntries()[0]; 16 17 const url = window.location.origin + '/images/blue.png'; 18 // blue.png is 133 by 106. 19 const size = 133 * 106; 20 checkImage(entry, url, 'image_id', size, beforeLoad); 21 }) 22 ); 23 observer.observe({type: 'largest-contentful-paint', buffered: true}); 24 }, 'Same-origin image after a JS initiated scroll event is observable.'); 25 document.body.dispatchEvent(new Event('scroll')); 26 const image = new Image(); 27 image.id = 'image_id'; 28 image.src = '/images/blue.png'; 29 document.body.appendChild(image); 30 </script> 31 32 </body>