| <!DOCTYPE html> |
| <html> |
| <meta charset=utf-8 /> |
| <title>Event Timing: only observe the first input</title> |
| <button id='button'>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-test-utils.js></script> |
| |
| <script> |
| /* Test: |
| PerformanceObserver for first-input is registered |
| Click 1 |
| Click 2 |
| Wait |
| Expected result: |
| PerformanceObserver should observe one and only one entry. |
| */ |
| async_test(function(t) { |
| if (!window.PerformanceEventTiming) |
| assert_unreached("PerformanceEventTiming is not supported"); |
| |
| let hasObservedFirstInput = false; |
| new PerformanceObserver(t.step_func((entryList) => { |
| assert_false(hasObservedFirstInput); |
| hasObservedFirstInput = true; |
| const observedEntries = entryList.getEntries().filter( |
| entry => entry.name === 'mousedown'); |
| assert_equals(observedEntries.length, 1); |
| assert_equals(observedEntries[0].entryType, 'first-input'); |
| assert_equals(observedEntries[0].name, 'mousedown'); |
| })).observe({ entryTypes: ['first-input'] }); |
| on_event(window, 'load', () => { |
| clickAndBlockMain('button').then(() => { |
| clickAndBlockMain('button').then(wait).then( () => { |
| // After some wait, the PerformanceObserver should have processed both clicks. |
| // One and only one first-input entry should have been dispatched, so |
| // |hasObservedFirstInput| should be true. |
| t.step_timeout( () => { |
| assert_true(hasObservedFirstInput); |
| t.done(); |
| }, 10); |
| }); |
| }); |
| }); |
| }, |
| "Event Timing: check first-input for a PerformanceObserver observing only first-input." |
| ); |
| </script> |
| </html> |
