| <html> |
| <head> |
| <title>The document timeline's current time should increase when the page rendering does not update.</title> |
| <script src="../resources/testharness.js"></script> |
| <script src="../resources/testharnessreport.js"></script> |
| </head> |
| |
| <body> |
| |
| <script> |
| |
| const pageRenderingUpdate = () => new Promise(requestAnimationFrame); |
| |
| const timeout = interval => new Promise(resolve => setTimeout(resolve, interval)); |
| |
| const timelineTimeBetweenPageRenderingUpdates = () => { |
| return new Promise(async (resolve, reject) => { |
| // Wait for an initial page rendering update to make sure we have a full |
| // page rendering update interval before we wait for a run loop that falls |
| // within a page rendering update interval. |
| await pageRenderingUpdate(); |
| |
| const maxAttempts = 10; |
| for (let numAttempts = 0; numAttempts < maxAttempts; numAttempts++) { |
| const pageRenderingUpdateTime = await pageRenderingUpdate(); |
| const timelineTime = document.timeline.currentTime; |
| |
| // Wait for the next run loop. |
| await timeout(0); |
| |
| // If that run loop was run less than 10ms after the page rendering update, |
| // we are in between two page rendering updates. |
| if (performance.now() - pageRenderingUpdateTime < 10) { |
| resolve(timelineTime); |
| break; |
| } |
| } |
| |
| reject(-1); |
| }); |
| } |
| |
| promise_test(async test => { |
| const initialTimelineTime = await timelineTimeBetweenPageRenderingUpdates(); |
| assert_equals(document.timeline.currentTime, initialTimelineTime, |
| "The timeline time should be the same during a page rendering update and in a run loop before the next page rendering update"); |
| |
| // Wait for 20ms which is more than the typical interval between two page rendering updates. |
| await timeout(20); |
| assert_greater_than(document.timeline.currentTime, initialTimelineTime, |
| "The timeline time should increase after waiting for over the typical duration between two page rendering updates"); |
| }, "The document timeline's current time should increase when the page rendering does not update."); |
| |
| </script> |
| |
| </body> |
| </html> |
