chromium/third_party/blink/web_tests/animations/web-animations/animation-null-timeline.html

<!DOCTYPE html>
<meta charset=utf-8>
<title>Operating on an animation with a null timeline</title>
<script src="../../resources/testharness.js"></script>
<script src="../../resources/testharnessreport.js"></script>
<body>
<script>
// Ensure that operations on an animation object are well behaved with a
// null timeline. TODO(crbug.com/967416) Consider moving to WPT once edge cases
// for handling of null timelines are fully flushed out.

// crbug.com/967509
test(t => {
  const effect = new KeyframeEffect(null, null, 1000);
  const animation = new Animation(effect, null);
  animation.finish();
  assert_equals(animation.startTime, null);
  assert_equals(animation.currentTime, 1000);
  assert_equals(animation.playState, 'paused');
}, 'Animation finished with a null timeline');

// crbug.com/967507
test(t => {
  const effect = new KeyframeEffect(null, null, 1000);
  const animation1 = document.body.animate([], 1000);
  assert_true(!!animation1.effect.target);
  const animation2 = new Animation(effect, null);
  assert_false(!!animation2.effect.target);
  animation2.pause();
  animation2.currentTime = 500;
  assert_equals(animation2.playState, 'paused');
  assert_equals(animation2.currentTime, 500);
  animation1.effect = effect;
  assert_false(!!animation1.effect.target);
  assert_false(!!animation2.effect);
  assert_equals(animation2.playState, 'paused');
}, 'Set effect with a null timeline');
</script>