| <!DOCTYPE HTML> |
| <meta charset=utf-8> |
| <title>Element Timing: observe with empty elementtiming attribute</title> |
| <script src="/resources/testharness.js"></script> |
| <script src="/resources/testharnessreport.js"></script> |
| <script src="resources/element-timing-helpers.js"></script> |
| <script> |
| let beforeRender; |
| async_test(function (t) { |
| assert_implements(window.PerformanceElementTiming, "PerformanceElementTiming is not implemented"); |
| let observedImage = false; |
| let observedText = false; |
| const observer = new PerformanceObserver( |
| t.step_func(function(entryList) { |
| entryList.getEntries().forEach(entry => { |
| if (entry.name === 'image-paint') { |
| assert_false(observedImage, 'Image should only be observed once.'); |
| const pathname = window.location.origin + '/element-timing/resources/square20.png'; |
| checkElement(entry, pathname, '', 'square', beforeRender, |
| document.getElementById('square')); |
| checkNaturalSize(entry, 20, 20); |
| observedImage = true; |
| } else { |
| assert_false(observedText, 'Text should only be observed once.'); |
| checkTextElement(entry, '', 'text', beforeRender, document.getElementById('text')); |
| observedText = true; |
| } |
| }); |
| if (observedImage && observedText) |
| t.done(); |
| }) |
| ); |
| observer.observe({type: 'element', buffered: true}); |
| beforeRender = performance.now(); |
| }, "Able to observe image and text with empty elementtiming attribute."); |
| </script> |
| <img id='square' src='resources/square20.png' elementtiming/> |
| <p id='text' elementtiming>Text!</p> |
