| <!DOCTYPE html> |
| <title>Layout Instability: sources attribute</title> |
| <link rel="help" href="https://wicg.github.io/layout-instability/" /> |
| <style> |
| |
| body { margin: 10px; } |
| #shifter { position: relative; width: 300px; height: 100px; background: blue; } |
| |
| </style> |
| <div id="shifter"></div> |
| <script src="/resources/testharness.js"></script> |
| <script src="/resources/testharnessreport.js"></script> |
| <script src="resources/util.js"></script> |
| <script> |
| |
| strrect = r => `[${r.x},${r.y},${r.width},${r.height}]`; |
| |
| promise_test(async () => { |
| const watcher = new ScoreWatcher; |
| const shifter = document.querySelector("#shifter"); |
| |
| // Wait for the initial render to complete. |
| await waitForAnimationFrames(2); |
| |
| // Modify the position of the div. |
| shifter.style = "top: 60px; left: 10px"; |
| await watcher.promise; |
| |
| const sources = watcher.lastEntry.sources; |
| assert_equals(sources.length, 1); |
| |
| const source = sources[0]; |
| assert_equals(source.node, shifter); |
| assert_equals(strrect(source.previousRect), "[10,10,300,100]"); |
| assert_equals(strrect(source.currentRect), "[20,70,300,100]"); |
| }, "Sources attribute."); |
| |
| </script> |