chromium/third_party/blink/web_tests/external/wpt/event-timing/interactionid-keypress.html

<!DOCTYPE html>
<html>
<meta charset=utf-8 />
<meta name="timeout" content="long">
<title>Event Timing: interactionId-keypress.</title>
<textarea id='test'></textarea>
<script src=/resources/testharness.js></script>
<script src=/resources/testharnessreport.js></script>
<script src=/resources/testdriver.js></script>
<script src=/resources/testdriver-actions.js></script>
<script src=/resources/testdriver-vendor.js></script>
<script src=resources/event-timing-test-utils.js></script>

<script>
  let observedEntries = [];
  let map = new Map();
          const events = ['keydown','keypress','keyup'];

  async_test(function (t) {
    assert_implements(window.PerformanceEventTiming, 'Event Timing is not supported.');

    new PerformanceObserver(t.step_func(entryList => {
      observedEntries = observedEntries.concat(entryList.getEntries().filter(filterAndAddToMap(events, map)));
      if (observedEntries.length < 3)
        return;
      assert_greater_than(map.get('keypress'), 0, 'Should have a non-trivial interactionId');
      assert_equals(map.get('keydown'), map.get('keypress'), 'The keydown and the keypress should have the same interactionId');
      assert_equals(map.get('keyup'), map.get('keypress'), 'The keyup and the keypress should have the same interactionId');
      assert_equals('t', document.getElementById('test').value);
      t.done();
    })).observe({ type: "event" });

    addListenersAndPress(document.getElementById('test'), 't', events);
  }, "Event Timing: compare event timing interactionId for keypress.");


</script>

</html>