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Test Info: Warnings
- This test has a WPT meta file that expects 1 subtest issues.
- This WPT test may be referenced by the following Test IDs:
- /longtask-timing/longtask-before-observer.window.html - WPT Dashboard Interop Dashboard
// META: script=resources/utils.js
async_test(t => {
assert_implements(window.PerformanceLongTaskTiming, 'Longtasks are not supported.');
// Create a long task before any observer.
const begin = window.performance.now();
while (window.performance.now() < begin + 60);
// After a timeout, add an observer with buffered flag.
t.step_timeout(() => {
new PerformanceObserver(t.step_func_done(list => {
list.getEntries().forEach(entry => {
checkLongTaskEntry(entry);
});
})).observe({type: 'longtask', buffered: true});
}, 0);
}, 'PerformanceObserver with buffered flag can see previous longtask entries.');