chromium/third_party/blink/web_tests/external/wpt/web-animations/interfaces/DocumentTimeline/constructor.html

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<title>DocumentTimeline constructor tests</title>
<link rel="help" href="https://drafts.csswg.org/web-animations/#the-documenttimeline-interface">
<script src="/resources/testharness.js"></script>
<script src="/resources/testharnessreport.js"></script>
<script src="../../testcommon.js"></script>
<script src="../../resources/timing-override.js"></script>
<body>
<div id="log"></div>
<script>
'use strict';

test(t => {
  const timeline = new DocumentTimeline();

  assert_times_equal(timeline.currentTime, document.timeline.currentTime);
}, 'An origin time of zero is used when none is supplied');

test(t => {
  const timeline = new DocumentTimeline({ originTime: 0 });
  assert_times_equal(timeline.currentTime, document.timeline.currentTime);
}, 'A zero origin time produces a document timeline with a current time ' +
   'identical to the default document timeline');

test(t => {
  const timeline = new DocumentTimeline({ originTime: 10 * MS_PER_SEC });

  assert_times_equal(timeline.currentTime,
                     (document.timeline.currentTime - 10 * MS_PER_SEC));
}, 'A positive origin time makes the document timeline\'s current time lag ' +
   'behind the default document timeline');

test(t => {
  const timeline = new DocumentTimeline({ originTime: -10 * MS_PER_SEC });

  assert_times_equal(timeline.currentTime,
                (document.timeline.currentTime + 10 * MS_PER_SEC));
}, 'A negative origin time makes the document timeline\'s current time run ' +
   'ahead of the default document timeline');

</script>
</body>