event-click-visibilitychange.html (3773B)
1 <!DOCTYPE html> 2 <html> 3 <meta charset=utf-8 /> 4 <meta name="timeout" content="long"> 5 <title>Event Timing: visibility change.</title> 6 <script src=/resources/testharness.js></script> 7 <script src=/resources/testharnessreport.js></script> 8 <script src=/resources/testdriver.js></script> 9 <script src=/resources/testdriver-vendor.js></script> 10 <script src=/resources/testdriver-actions.js></script> 11 <script src=/page-visibility/resources/window_state_context.js></script> 12 <script src=resources/event-timing-test-utils.js></script> 13 14 <body> 15 <button id='target'>Click me</button> 16 17 <script> 18 let observedEntries = []; 19 const map = new Map(); 20 const events = ['pointerup']; 21 22 promise_test(async t => { 23 assert_implements(window.PerformanceEventTiming, 'Event Timing is not supported.'); 24 25 const { minimize, restore } = window_state_context(t); 26 const button = document.getElementById('target'); 27 28 const callback = (entryList) => { observedEntries = observedEntries.concat(entryList.getEntries().filter(filterAndAddToMap(events, map))); }; 29 const readyToResolve = () => { return observedEntries.length >= 1; }; 30 const observerPromise = createPerformanceObserverPromise(['event'], callback, readyToResolve); 31 32 const tapEventPromise = new Promise(resolve => { 33 button.addEventListener('pointerup', async (event) => { 34 document.body.innerText += "Adding content to force rendering"; 35 36 // await here will yield to event loop, and end event processing time, 37 // which will allow rendering to continue. 38 // The visibility change may happen before rendering has a chance 39 // but it is not guarenteed which will happen first. 40 await minimize(); 41 const timeAfterVisibilityFalse = performance.now(); 42 43 await restore(); 44 const timeAfterVisibilityTrue = performance.now(); 45 46 resolve({ timeAfterVisibilityFalse, timeAfterVisibilityTrue }); 47 }); 48 }); 49 50 // A buffered visibility-state PerformanceEntry would have made this test 51 // cleaner, due to the variability of ordering of events, but it is not 52 // yet available. 53 const visibilityEventPromise = new Promise(resolve => { 54 document.addEventListener('visibilitychange', (event) => { 55 if (document.visibilityState !== 'visible') { 56 resolve(performance.now()); 57 } 58 }); 59 }); 60 61 const timeBeforeTap = performance.now(); 62 await interactAndObserve('tap', button, observerPromise); 63 64 // The order that these events fire is non-deterministic, but we can await 65 // the result of the promise in any order. 66 const { timeAfterVisibilityFalse, timeAfterVisibilityTrue } = await tapEventPromise; 67 const timeOfVisibilityFalse = await visibilityEventPromise; 68 69 assert_equals(observedEntries.length, 1, "Pointerup was measured"); 70 const entry = observedEntries[0]; 71 72 assert_not_equals(timeBeforeTap, undefined); 73 assert_not_equals(timeAfterVisibilityFalse, undefined); 74 assert_not_equals(timeAfterVisibilityTrue, undefined); 75 assert_not_equals(timeOfVisibilityFalse, undefined); 76 77 assert_less_than( 78 entry.processingEnd, 79 timeOfVisibilityFalse, 80 "event handler ends before visibility event fires" 81 ); 82 assert_less_than( 83 timeOfVisibilityFalse, 84 timeAfterVisibilityFalse, 85 "visibility event fires before event handler continues" 86 ); 87 assert_less_than_equal( 88 entry.startTime + entry.duration, 89 timeAfterVisibilityFalse, 90 "event duration ends before visibility is changed" 91 ); 92 93 }, "Event handlers which change visibility should not measure next paint."); 94 95 </script> 96 </body> 97 98 </html>