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Test Info:
- This WPT test may be referenced by the following Test IDs:
- /performance-timeline/webtiming-resolution.any.html - WPT Dashboard Interop Dashboard
- /performance-timeline/webtiming-resolution.any.worker.html - WPT Dashboard Interop Dashboard
function testTimeResolution(highResTimeFunc, funcString) {
test(() => {
const t0 = highResTimeFunc();
let t1 = highResTimeFunc();
while (t0 == t1) {
t1 = highResTimeFunc();
}
const epsilon = 1e-5;
assert_greater_than_equal(t1 - t0, 0.005 - epsilon, 'The second ' + funcString + ' should be much greater than the first');
}, 'Verifies the resolution of ' + funcString + ' is at least 5 microseconds.');
}
function timeByPerformanceNow() {
return performance.now();
}
function timeByUserTiming() {
performance.mark('timer');
const time = performance.getEntriesByName('timer')[0].startTime;
performance.clearMarks('timer');
return time;
}
testTimeResolution(timeByPerformanceNow, 'performance.now()');
testTimeResolution(timeByUserTiming, 'entry.startTime');