| <!DOCTYPE html> |
| <title>Layout Instability: visibility:hidden change with layout</title> |
| <link rel="help" href="https://wicg.github.io/layout-instability/" /> |
| <div id="target" style="position: absolute; top: 0; width: 200px; height: 200px; visibility: hidden; background: blue"></div> |
| <script src="/resources/testharness.js"></script> |
| <script src="/resources/testharnessreport.js"></script> |
| <script src="resources/util.js"></script> |
| <script> |
| |
| promise_test(async () => { |
| const watcher = new ScoreWatcher; |
| |
| // Wait for the initial render to complete. |
| await waitForAnimationFrames(2); |
| |
| // Shift target, for which no shift should be reported because it's hidden. |
| target.style.top = '200px'; |
| target.style.visibility = 'visible'; |
| |
| await waitForAnimationFrames(2); |
| // No shift should be reported. |
| assert_equals(watcher.score, 0); |
| |
| // Shift again, for which shift should be reported. |
| target.style.top = '300px'; |
| |
| await watcher.promise; |
| const expectedScore = computeExpectedScore(200 * (200 + 100), 100); |
| assert_equals(watcher.score, expectedScore); |
| |
| }, 'visibility:hidden change with layout'); |
| |
| </script> |