| <!DOCTYPE html> |
| <title>Layout Instability: inline/text movement is detected</title> |
| <link rel="help" href="https://wicg.github.io/layout-instability/" /> |
| <script src="/resources/testharness.js"></script> |
| <script src="/resources/testharnessreport.js"></script> |
| <script src="resources/util.js"></script> |
| <div style="width: 200px; font-size: 20px; line-height: 25px"> |
| 1AAAAAAA<br> |
| 2AAAAAAA<br> |
| 3AAAAAAA<br> |
| <div id="inline-block" style="display: inline-block; height: 50px">4AAAAAAA</div><br> |
| 5AAAAAAA<br> |
| 6AAAAAAA<br> |
| 7AAAAAAA<br> |
| </div> |
| <script> |
| |
| promise_test(async () => { |
| const watcher = new ScoreWatcher; |
| |
| // Wait for the initial render to complete. |
| await waitForAnimationFrames(2); |
| |
| // Modify the position of the div. |
| const inline_block = document.querySelector("#inline-block"); |
| inline_block.style.height = '100px'; |
| |
| // The lines below the inline-block are shifted down by 50px. |
| // The implementation may measure the real width of the shifted text |
| // or use the available width (i.e. width of the containing block). |
| // Also tolerate extra 10% error. |
| const text_width = inline_block.offsetWidth; |
| const expectedScoreMin = computeExpectedScore(text_width * (30 * 3 + 50), 50) * 0.9; |
| const expectedScoreMax = computeExpectedScore(200 * (30 * 3 + 50), 50) * 1.1; |
| |
| // Observer fires after the frame is painted. |
| assert_equals(watcher.score, 0); |
| await watcher.promise; |
| assert_between_exclusive(watcher.score, expectedScoreMin, expectedScoreMax); |
| }, 'Inline flow movement.'); |
| |
| </script> |