| <!DOCTYPE html> |
| <html> |
| <meta charset=utf-8 /> |
| <title>Event Timing: long-latency events after onload and before observer |
| registration are lost |
| </title> |
| <button id='button' onclick='1'>Generate a 'click' event</button> |
| <script src=/resources/testharness.js></script> |
| <script src=/resources/testharnessreport.js></script> |
| <script src=/resources/testdriver.js></script> |
| <script src=/resources/testdriver-vendor.js></script> |
| |
| <script src=resources/event-timing-support.js></script> |
| <script> |
| let callbackTime; |
| let observerStart; |
| let processingStartMin; |
| |
| function verifyBufferAndObserverEntries(observedEntries) { |
| // Verify buffer entries |
| const bufferedEntries = performance.getEntriesByName('click', 'event'); |
| const bufferedEntriesBeforeObserver = bufferedEntries.filter(e => e.startTime < |
| observerStart); |
| assert_equals(bufferedEntries.length, 0, |
| "Long latency events after onload should not be buffered." |
| ); |
| |
| // Verify observer entries |
| assert_equals(observedEntries.length, 1, "Long latency task after observer start should be observed."); |
| const entry = observedEntries[0]; |
| verifyClickEvent(entry); |
| assert_greater_than(entry.processingStart, processingStartMin, |
| "The entry's processing start should be later than processingStartMin."); |
| assert_greater_than(callbackTime, entry.processingStart, |
| "The callback time should be later than the entry's processing start."); |
| assert_greater_than(entry.startTime, observerStart, |
| "The entry's start time should be later than observer start."); |
| assert_greater_than(callbackTime, entry.startTime, |
| "The callback time should be later than entry's start time."); |
| } |
| |
| function startObserver(t) { |
| new PerformanceObserver(t.step_func_done((entryList, obs) => { |
| callbackTime = performance.now(); |
| const observedEntries = entryList.getEntries(); |
| verifyBufferAndObserverEntries(observedEntries); |
| })).observe({ entryTypes: ['event'] }); |
| observerStart = performance.now(); |
| } |
| |
| /* Timeline: |
| Onload Event fires |
| Begin Busy Loop |
| Click 1 arrives |
| End Busy Loop |
| (Dispatch and Process Click 1 (not buffered, not observed)) |
| Observer start |
| Begin Busy Loop |
| Click 2 arrives |
| End Busy Loop |
| (Dispatch and Process Click 2 (not buffered, observed)) |
| */ |
| async_test(function(t) { |
| on_event(window, 'load', () => { |
| clickAndBlockMain('button').then(() => { |
| startObserver(t); |
| clickAndBlockMain('button').then(wait); |
| processingStartMin = performance.now(); |
| }); |
| }); |
| }, |
| "Event Timing: onload, click, observer, click." |
| ); |
| |
| </script> |
| </html> |
