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Test Info: Warnings

<!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) {
assert_implements(window.PerformanceEventTiming, 'Event Timing 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>