File: test_animation_observers_sync.html

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<!DOCTYPE html>
<meta charset=utf-8>
<title>
Test chrome-only MutationObserver animation notifications (sync tests)
</title>
<!--

  This file contains synchronous tests for animation mutation observers.

  In general we prefer to write synchronous tests since they are less likely to
  timeout when run on automation. Tests that require asynchronous steps (e.g.
  waiting on events) should be added to test_animations_observers_async.html
  instead.

-->
<script type="application/javascript" src="../testharness.js"></script>
<script type="application/javascript" src="../testharnessreport.js"></script>
<script type="application/javascript" src="../testcommon.js"></script>
<div id="log"></div>
<style>
@keyframes anim {
  to { transform: translate(100px); }
}
@keyframes anotherAnim {
  to { transform: translate(0px); }
}
</style>
<script>

/**
 * Return a new MutationObserver which observing |target| element
 * with { animations: true, subtree: |subtree| } option.
 *
 * NOTE: This observer should be used only with takeRecords(). If any of
 * MutationRecords are observed in the callback of the MutationObserver,
 * it will raise an assertion.
 */
function setupSynchronousObserver(t, target, subtree) {
  var observer = new MutationObserver(records => {
    assert_unreached("Any MutationRecords should not be observed in this " +
                     "callback");
  });
  t.add_cleanup(() => {
    observer.disconnect();
  });
  observer.observe(target, { animations: true, subtree });
  return observer;
}

function assert_record_list(actual, expected, desc, index, listName) {
  assert_equals(actual.length, expected.length,
                `${desc} - record[${index}].${listName} length`);
  if (actual.length != expected.length) {
    return;
  }
  for (var i = 0; i < actual.length; i++) {
    assert_not_equals(actual.indexOf(expected[i]), -1,
       `${desc} - record[${index}].${listName} contains expected Animation`);
  }
}

function assert_equals_records(actual, expected, desc) {
  assert_equals(actual.length, expected.length, `${desc} - number of records`);
  if (actual.length != expected.length) {
    return;
  }
  for (var i = 0; i < actual.length; i++) {
    assert_record_list(actual[i].addedAnimations,
                       expected[i].added, desc, i, "addedAnimations");
    assert_record_list(actual[i].changedAnimations,
                       expected[i].changed, desc, i, "changedAnimations");
    assert_record_list(actual[i].removedAnimations,
                       expected[i].removed, desc, i, "removedAnimations");
  }
}

function runTest() {
  [ { subtree: false },
    { subtree: true }
  ].forEach(aOptions => {
    test(t => {
      var div = addDiv(t);
      var observer =
        setupSynchronousObserver(t,
                                 aOptions.subtree ? div.parentNode : div,
                                 aOptions.subtree);

      var anim = div.animate({ opacity: [ 0, 1 ] }, 200 * MS_PER_SEC);

      assert_equals_records(observer.takeRecords(),
        [{ added: [anim], changed: [], removed: [] }],
        "records after animation is added");

      anim.effect.updateTiming({ duration: 100 * MS_PER_SEC });
      assert_equals_records(observer.takeRecords(),
        [{ added: [], changed: [anim], removed: [] }],
        "records after duration is changed");

      anim.effect.updateTiming({ duration: 100 * MS_PER_SEC });
      assert_equals_records(observer.takeRecords(),
        [], "records after assigning same value");

      anim.currentTime = anim.effect.getComputedTiming().duration * 2;
      anim.finish();
      assert_equals_records(observer.takeRecords(),
        [{ added: [], changed: [], removed: [anim] }],
        "records after animation end");

      anim.effect.updateTiming({
        duration: anim.effect.getComputedTiming().duration * 3
      });
      assert_equals_records(observer.takeRecords(),
        [{ added: [anim], changed: [], removed: [] }],
        "records after animation restarted");

      anim.effect.updateTiming({ duration: 'auto' });
      assert_equals_records(observer.takeRecords(),
        [{ added: [], changed: [], removed: [anim] }],
        "records after duration set \"auto\"");

      anim.effect.updateTiming({ duration: 'auto' });
      assert_equals_records(observer.takeRecords(),
        [], "records after assigning same value \"auto\"");
    }, "change_duration_and_currenttime");

    test(t => {
      var div = addDiv(t);
      var observer =
        setupSynchronousObserver(t,
                                 aOptions.subtree ? div.parentNode : div,
                                 aOptions.subtree);

      var anim = div.animate({ opacity: [ 0, 1 ] }, 100 * MS_PER_SEC);

      assert_equals_records(observer.takeRecords(),
        [{ added: [anim], changed: [], removed: [] }],
        "records after animation is added");

      anim.effect.updateTiming({ endDelay: 10 * MS_PER_SEC });
      assert_equals_records(observer.takeRecords(),
        [{ added: [], changed: [anim], removed: [] }],
        "records after endDelay is changed");

      anim.effect.updateTiming({ endDelay: 10 * MS_PER_SEC });
      assert_equals_records(observer.takeRecords(),
        [], "records after assigning same value");

      anim.currentTime = 109 * MS_PER_SEC;
      assert_equals_records(observer.takeRecords(),
        [{ added: [], changed: [], removed: [anim] }],
        "records after currentTime during endDelay");

      anim.effect.updateTiming({ endDelay: -110 * MS_PER_SEC });
      assert_equals_records(observer.takeRecords(),
        [], "records after assigning negative value");
    }, "change_enddelay_and_currenttime");

    test(t => {
      var div = addDiv(t);
      var observer =
        setupSynchronousObserver(t,
                                 aOptions.subtree ? div.parentNode : div,
                                 aOptions.subtree);

      var anim = div.animate({ opacity: [ 0, 1 ] },
                             { duration: 100 * MS_PER_SEC,
                               endDelay: -100 * MS_PER_SEC });
      assert_equals_records(observer.takeRecords(),
        [], "records after animation is added");
    }, "zero_end_time");

    test(t => {
      var div = addDiv(t);
      var observer =
        setupSynchronousObserver(t,
                                 aOptions.subtree ? div.parentNode : div,
                                 aOptions.subtree);

      var anim = div.animate({ opacity: [ 0, 1 ] }, 100 * MS_PER_SEC);

      assert_equals_records(observer.takeRecords(),
        [{ added: [anim], changed: [], removed: [] }],
        "records after animation is added");

      anim.effect.updateTiming({ iterations: 2 });
      assert_equals_records(observer.takeRecords(),
        [{ added: [], changed: [anim], removed: [] }],
        "records after iterations is changed");

      anim.effect.updateTiming({ iterations: 2 });
      assert_equals_records(observer.takeRecords(),
        [], "records after assigning same value");

      anim.effect.updateTiming({ iterations: 0 });
      assert_equals_records(observer.takeRecords(),
        [{ added: [], changed: [], removed: [anim] }],
        "records after animation end");

      anim.effect.updateTiming({ iterations: Infinity });
      assert_equals_records(observer.takeRecords(),
        [{ added: [anim], changed: [], removed: [] }],
        "records after animation restarted");
    }, "change_iterations");

    test(t => {
      var div = addDiv(t);
      var observer =
        setupSynchronousObserver(t,
                                 aOptions.subtree ? div.parentNode : div,
                                 aOptions.subtree);

      var anim = div.animate({ opacity: [ 0, 1 ] }, 100 * MS_PER_SEC);

      assert_equals_records(observer.takeRecords(),
        [{ added: [anim], changed: [], removed: [] }],
        "records after animation is added");

      anim.effect.updateTiming({ delay: 100 });
      assert_equals_records(observer.takeRecords(),
        [{ added: [], changed: [anim], removed: [] }],
        "records after delay is changed");

      anim.effect.updateTiming({ delay: 100 });
      assert_equals_records(observer.takeRecords(),
        [], "records after assigning same value");

      anim.effect.updateTiming({ delay: -100 * MS_PER_SEC });
      assert_equals_records(observer.takeRecords(),
        [{ added: [], changed: [], removed: [anim] }],
        "records after animation end");

      anim.effect.updateTiming({ delay: 0 });
      assert_equals_records(observer.takeRecords(),
        [{ added: [anim], changed: [], removed: [] }],
        "records after animation restarted");
    }, "change_delay");

    test(t => {
      var div = addDiv(t);
      var observer =
        setupSynchronousObserver(t,
                                 aOptions.subtree ? div.parentNode : div,
                                 aOptions.subtree);

      var anim = div.animate({ opacity: [ 0, 1 ] },
                             { duration: 100 * MS_PER_SEC,
                               easing: "steps(2, start)" });

      assert_equals_records(observer.takeRecords(),
        [{ added: [anim], changed: [], removed: [] }],
        "records after animation is added");

      anim.effect.updateTiming({ easing: "steps(2, end)" });
      assert_equals_records(observer.takeRecords(),
        [{ added: [], changed: [anim], removed: [] }],
        "records after easing is changed");

      anim.effect.updateTiming({ easing: "steps(2, end)" });
      assert_equals_records(observer.takeRecords(),
        [], "records after assigning same value");
    }, "change_easing");

    test(t => {
      var div = addDiv(t);
      var observer =
        setupSynchronousObserver(t,
                                 aOptions.subtree ? div.parentNode : div,
                                 aOptions.subtree);

      var anim = div.animate({ opacity: [ 0, 1 ] },
                             { duration: 100, delay: -100 });
      assert_equals_records(observer.takeRecords(),
        [], "records after assigning negative value");
    }, "negative_delay_in_constructor");

    test(t => {
      var div = addDiv(t);
      var observer =
        setupSynchronousObserver(t,
                                 aOptions.subtree ? div.parentNode : div,
                                 aOptions.subtree);

      var effect = new KeyframeEffect(null,
                                      { opacity: [ 0, 1 ] },
                                      { duration: 100 * MS_PER_SEC });
      var anim = new Animation(effect, document.timeline);
      anim.play();
      assert_equals_records(observer.takeRecords(),
        [], "no records after animation is added");
    }, "create_animation_without_target");

    test(t => {
      var div = addDiv(t);
      var observer =
        setupSynchronousObserver(t,
                                 aOptions.subtree ? div.parentNode : div,
                                 aOptions.subtree);

      var anim = div.animate({ opacity: [ 0, 1 ] },
                             { duration: 100 * MS_PER_SEC });
      assert_equals_records(observer.takeRecords(),
        [{ added: [anim], changed: [], removed: [] }],
        "records after animation is added");

      anim.effect.target = div;
      assert_equals_records(observer.takeRecords(),
        [], "no records after setting the same target");

      anim.effect.target = null;
      assert_equals_records(observer.takeRecords(),
        [{ added: [], changed: [], removed: [anim] }],
        "records after setting null");

      anim.effect.target = null;
      assert_equals_records(observer.takeRecords(),
        [], "records after setting redundant null");
    }, "set_redundant_animation_target");

    test(t => {
      var div = addDiv(t);
      var observer =
        setupSynchronousObserver(t,
                                 aOptions.subtree ? div.parentNode : div,
                                 aOptions.subtree);

      var anim = div.animate({ opacity: [ 0, 1 ] },
                             { duration: 100 * MS_PER_SEC });
      assert_equals_records(observer.takeRecords(),
        [{ added: [anim], changed: [], removed: [] }],
        "records after animation is added");

      anim.effect = null;
      assert_equals_records(observer.takeRecords(),
        [{ added: [], changed: [], removed: [anim] }],
        "records after animation is removed");
    }, "set_null_animation_effect");

    test(t => {
      var div = addDiv(t);
      var observer =
        setupSynchronousObserver(t,
                                 aOptions.subtree ? div.parentNode : div,
                                 aOptions.subtree);

      var anim = new Animation();
      anim.play();
      anim.effect = new KeyframeEffect(div, { opacity: [ 0, 1 ] },
                                       100 * MS_PER_SEC);
      assert_equals_records(observer.takeRecords(),
        [{ added: [anim], changed: [], removed: [] }],
        "records after animation is added");
    }, "set_effect_on_null_effect_animation");

    test(t => {
      var div = addDiv(t);
      var observer =
        setupSynchronousObserver(t,
                                 aOptions.subtree ? div.parentNode : div,
                                 aOptions.subtree);

      var anim = div.animate({ marginLeft: [ "0px", "100px" ] },
                             100 * MS_PER_SEC);
      assert_equals_records(observer.takeRecords(),
        [{ added: [anim], changed: [], removed: [] }],
        "records after animation is added");

      anim.effect = new KeyframeEffect(div, { opacity: [ 0, 1 ] },
                                       100 * MS_PER_SEC);
      assert_equals_records(observer.takeRecords(),
        [{ added: [], changed: [anim], removed: [] }],
        "records after replace effects");
    }, "replace_effect_targeting_on_the_same_element");

    test(t => {
      var div = addDiv(t);
      var observer =
        setupSynchronousObserver(t,
                                 aOptions.subtree ? div.parentNode : div,
                                 aOptions.subtree);

      var anim = div.animate({ marginLeft: [ "0px", "100px" ] },
                             100 * MS_PER_SEC);
      assert_equals_records(observer.takeRecords(),
        [{ added: [anim], changed: [], removed: [] }],
        "records after animation is added");

      anim.currentTime = 60 * MS_PER_SEC;
      assert_equals_records(observer.takeRecords(),
        [{ added: [], changed: [anim], removed: [] }],
        "records after animation is changed");

      anim.effect = new KeyframeEffect(div, { opacity: [ 0, 1 ] },
                                       50 * MS_PER_SEC);
      assert_equals_records(observer.takeRecords(),
        [{ added: [], changed: [], removed: [anim] }],
        "records after replacing effects");
    }, "replace_effect_targeting_on_the_same_element_not_in_effect");

    test(t => {
      var div = addDiv(t);
      var observer =
        setupSynchronousObserver(t,
                                 aOptions.subtree ? div.parentNode : div,
                                 aOptions.subtree);

      var anim = div.animate({ }, 100 * MS_PER_SEC);
      assert_equals_records(observer.takeRecords(),
        [{ added: [anim], changed: [], removed: [] }],
        "records after animation is added");

      anim.effect.composite = "add";
      assert_equals_records(observer.takeRecords(),
        [{ added: [], changed: [anim], removed: [] }],
        "records after composite is changed");

      anim.effect.composite = "add";
      assert_equals_records(observer.takeRecords(),
        [], "no record after setting the same composite");

    }, "set_composite");

    // Test that starting a single animation that is cancelled by calling
    // cancel() dispatches an added notification and then a removed
    // notification.
    test(t => {
      var div = addDiv(t, { style: "animation: anim 100s forwards" });
      var observer =
        setupSynchronousObserver(t,
                                 aOptions.subtree ? div.parentNode : div,
                                 aOptions.subtree);

      var animations = div.getAnimations();
      assert_equals(animations.length, 1,
        "getAnimations().length after animation start");

      assert_equals_records(observer.takeRecords(),
        [{ added: animations, changed: [], removed: [] }],
        "records after animation start");

      animations[0].cancel();

      assert_equals_records(observer.takeRecords(),
        [{ added: [], changed: [], removed: animations }],
        "records after animation end");

      // Re-trigger the animation.
      animations[0].play();

      // Single MutationRecord for the Animation (re-)addition.
      assert_equals_records(observer.takeRecords(),
        [{ added: animations, changed: [], removed: [] }],
        "records after animation start");
    }, "single_animation_cancelled_api");

    // Test that updating a property on the Animation object dispatches a changed
    // notification.
    [
      { prop: "playbackRate", val: 0.5 },
      { prop: "startTime",    val: 50 * MS_PER_SEC },
      { prop: "currentTime",  val: 50 * MS_PER_SEC },
    ].forEach(aChangeTest => {
      test(t => {
        // We use a forwards fill mode so that even if the change we make causes
        // the animation to become finished, it will still be "relevant" so we
        // won't mark it as removed.
        var div = addDiv(t, { style: "animation: anim 100s forwards" });
        var observer =
          setupSynchronousObserver(t,
                                   aOptions.subtree ? div.parentNode : div,
                                   aOptions.subtree);

        var animations = div.getAnimations();
        assert_equals(animations.length, 1,
          "getAnimations().length after animation start");

        assert_equals_records(observer.takeRecords(),
          [{ added: animations, changed: [], removed: [] }],
          "records after animation start");

        // Update the property.
        animations[0][aChangeTest.prop] = aChangeTest.val;

        // Make a redundant change.
        // eslint-disable-next-line no-self-assign
        animations[0][aChangeTest.prop] = animations[0][aChangeTest.prop];

        assert_equals_records(observer.takeRecords(),
          [{ added: [], changed: animations, removed: [] }],
          "records after animation property change");
      }, `single_animation_api_change_${aChangeTest.prop}`);
    });

    // Test that making a redundant change to currentTime while an Animation
    // is pause-pending still generates a change MutationRecord since setting
    // the currentTime to any value in this state aborts the pending pause.
    test(t => {
      var div = addDiv(t, { style: "animation: anim 100s" });
      var observer =
        setupSynchronousObserver(t,
                                 aOptions.subtree ? div.parentNode : div,
                                 aOptions.subtree);

      var animations = div.getAnimations();
      assert_equals(animations.length, 1,
        "getAnimations().length after animation start");

      assert_equals_records(observer.takeRecords(),
        [{ added: animations, changed: [], removed: [] }],
        "records after animation start");

      animations[0].pause();

      // We are now pause-pending. Even if we make a redundant change to the
      // currentTime, we should still get a change record because setting the
      // currentTime while pause-pending has the effect of cancelling a pause.
      // eslint-disable-next-line no-self-assign
      animations[0].currentTime = animations[0].currentTime;

      // Two MutationRecords for the Animation changes: one for pausing, one
      // for aborting the pause.
      assert_equals_records(observer.takeRecords(),
        [{ added: [], changed: animations, removed: [] },
         { added: [], changed: animations, removed: [] }],
        "records after pausing then seeking");
    }, "change_currentTime_while_pause_pending");

    // Test that calling finish() on a forwards-filling Animation dispatches
    // a changed notification.
    test(t => {
      var div = addDiv(t, { style: "animation: anim 100s forwards" });
      var observer =
        setupSynchronousObserver(t,
                                 aOptions.subtree ? div.parentNode : div,
                                 aOptions.subtree);

      var animations = div.getAnimations();
      assert_equals(animations.length, 1,
        "getAnimations().length after animation start");

      assert_equals_records(observer.takeRecords(),
        [{ added: animations, changed: [], removed: [] }],
        "records after animation start");

      animations[0].finish();

      assert_equals_records(observer.takeRecords(),
        [{ added: [], changed: animations, removed: [] }],
        "records after finish()");

      // Redundant finish.
      animations[0].finish();

      // Ensure no change records.
      assert_equals_records(observer.takeRecords(),
        [], "records after redundant finish()");
    }, "finish_with_forwards_fill");

    // Test that calling finish() on an Animation that does not fill forwards,
    // dispatches a removal notification.
    test(t => {
      var div = addDiv(t, { style: "animation: anim 100s" });
      var observer =
        setupSynchronousObserver(t,
                                 aOptions.subtree ? div.parentNode : div,
                                 aOptions.subtree);

      var animations = div.getAnimations();
      assert_equals(animations.length, 1,
        "getAnimations().length after animation start");

      assert_equals_records(observer.takeRecords(),
        [{ added: animations, changed: [], removed: [] }],
        "records after animation start");

      animations[0].finish();

      // Single MutationRecord for the Animation removal.
      assert_equals_records(observer.takeRecords(),
        [{ added: [], changed: [], removed: animations }],
        "records after finishing");
    }, "finish_without_fill");

    // Test that calling finish() on a forwards-filling Animation dispatches
    test(t => {
      var div = addDiv(t, { style: "animation: anim 100s" });
      var observer =
        setupSynchronousObserver(t,
                                 aOptions.subtree ? div.parentNode : div,
                                 aOptions.subtree);

      var animation = div.getAnimations()[0];
      assert_equals_records(observer.takeRecords(),
        [{ added: [animation], changed: [], removed: []}],
        "records after creation");
      animation.id = "new id";
      assert_equals_records(observer.takeRecords(),
        [{ added: [], changed: [animation], removed: []}],
        "records after id is changed");

      animation.id = "new id";
      assert_equals_records(observer.takeRecords(),
        [], "records after assigning same value with id");
    }, "change_id");

    // Test that calling reverse() dispatches a changed notification.
    test(t => {
      var div = addDiv(t, { style: "animation: anim 100s both" });
      var observer =
        setupSynchronousObserver(t,
                                 aOptions.subtree ? div.parentNode : div,
                                 aOptions.subtree);

      var animations = div.getAnimations();
      assert_equals(animations.length, 1,
        "getAnimations().length after animation start");

      assert_equals_records(observer.takeRecords(),
        [{ added: animations, changed: [], removed: [] }],
        "records after animation start");

      animations[0].reverse();

      assert_equals_records(observer.takeRecords(),
        [{ added: [], changed: animations, removed: [] }],
        "records after calling reverse()");
    }, "reverse");

    // Test that calling reverse() does *not* dispatch a changed notification
    // when playbackRate == 0.
    test(t => {
      var div = addDiv(t, { style: "animation: anim 100s both" });
      var observer =
        setupSynchronousObserver(t,
                                 aOptions.subtree ? div.parentNode : div,
                                 aOptions.subtree);

      var animations = div.getAnimations();
      assert_equals(animations.length, 1,
        "getAnimations().length after animation start");

      assert_equals_records(observer.takeRecords(),
        [{ added: animations, changed: [], removed: [] }],
        "records after animation start");

      // Seek to the middle and set playbackRate to zero.
      animations[0].currentTime = 50 * MS_PER_SEC;
      animations[0].playbackRate = 0;

      // Two MutationRecords, one for each change.
      assert_equals_records(observer.takeRecords(),
        [{ added: [], changed: animations, removed: [] },
         { added: [], changed: animations, removed: [] }],
        "records after seeking and setting playbackRate");

      animations[0].reverse();

      // We should get no notifications.
      assert_equals_records(observer.takeRecords(),
        [], "records after calling reverse()");
    }, "reverse_with_zero_playbackRate");

    // Test that reverse() on an Animation does *not* dispatch a changed
    // notification when it throws an exception.
    test(t => {
      // Start an infinite animation
      var div = addDiv(t, { style: "animation: anim 10s infinite" });
      var observer =
        setupSynchronousObserver(t,
                                 aOptions.subtree ? div.parentNode : div,
                                 aOptions.subtree);

      var animations = div.getAnimations();
      assert_equals(animations.length, 1,
        "getAnimations().length after animation start");

      assert_equals_records(observer.takeRecords(),
        [{ added: animations, changed: [], removed: [] }],
        "records after animation start");

      // Shift the animation into the future such that when we call reverse
      // it will try to seek to the (infinite) end.
      animations[0].startTime = 100 * MS_PER_SEC;

      assert_equals_records(observer.takeRecords(),
        [{ added: [], changed: animations, removed: [] }],
        "records after adjusting startTime");

      // Reverse: should throw
      assert_throws('InvalidStateError', () => {
        animations[0].reverse();
      }, 'reverse() on future infinite animation throws an exception');

      // We should get no notifications.
      assert_equals_records(observer.takeRecords(),
        [], "records after calling reverse()");
    }, "reverse_with_exception");

    // Test that attempting to start an animation that should already be finished
    // does not send any notifications.
    test(t => {
      // Start an animation that should already be finished.
      var div = addDiv(t, { style: "animation: anim 1s -2s;" });
      var observer =
        setupSynchronousObserver(t,
                                 aOptions.subtree ? div.parentNode : div,
                                 aOptions.subtree);

      // The animation should cause no Animations to be created.
      var animations = div.getAnimations();
      assert_equals(animations.length, 0,
        "getAnimations().length after animation start");

      // And we should get no notifications.
      assert_equals_records(observer.takeRecords(),
        [], "records after attempted animation start");
    }, "already_finished");

    test(t => {
      var div = addDiv(t, { style: "animation: anim 100s, anotherAnim 100s" });
      var observer =
        setupSynchronousObserver(t,
                                 aOptions.subtree ? div.parentNode : div,
                                 aOptions.subtree);

      var animations = div.getAnimations();

      assert_equals_records(observer.takeRecords(),
        [{ added: animations, changed: [], removed: []}],
        "records after creation");

      div.style.animation = "anotherAnim 100s, anim 100s";
      animations = div.getAnimations();

      assert_equals_records(observer.takeRecords(),
        [{ added: [], changed: animations, removed: []}],
        "records after the order is changed");

      div.style.animation = "anotherAnim 100s, anim 100s";

      assert_equals_records(observer.takeRecords(),
        [], "no records after applying the same order");
    }, "animation_order_change");

    test(t => {
      var div = addDiv(t);
      var observer =
        setupSynchronousObserver(t,
                                 aOptions.subtree ? div.parentNode : div,
                                 aOptions.subtree);

      var anim = div.animate({ opacity: [ 0, 1 ] },
                             { duration: 100 * MS_PER_SEC,
                               iterationComposite: 'replace' });

      assert_equals_records(observer.takeRecords(),
        [{ added: [anim], changed: [], removed: [] }],
        "records after animation is added");

      anim.effect.iterationComposite = 'accumulate';
      assert_equals_records(observer.takeRecords(),
        [{ added: [], changed: [anim], removed: [] }],
        "records after iterationComposite is changed");

      anim.effect.iterationComposite = 'accumulate';
      assert_equals_records(observer.takeRecords(),
        [], "no record after setting the same iterationComposite");

    }, "set_iterationComposite");

    test(t => {
      var div = addDiv(t);
      var observer =
        setupSynchronousObserver(t,
                                 aOptions.subtree ? div.parentNode : div,
                                 aOptions.subtree);

      var anim = div.animate({ opacity: [ 0, 1 ] },
                             { duration: 100 * MS_PER_SEC });

      assert_equals_records(observer.takeRecords(),
        [{ added: [anim], changed: [], removed: [] }],
        "records after animation is added");

      anim.effect.setKeyframes({ opacity: 0.1 });
      assert_equals_records(observer.takeRecords(),
        [{ added: [], changed: [anim], removed: [] }],
        "records after keyframes are changed");

      anim.effect.setKeyframes({ opacity: 0.1 });
      assert_equals_records(observer.takeRecords(),
        [], "no record after setting the same keyframes");

      anim.effect.setKeyframes(null);
      assert_equals_records(observer.takeRecords(),
        [{ added: [], changed: [anim], removed: [] }],
        "records after keyframes are set to empty");

    }, "set_keyframes");

    // Test that starting a single transition that is cancelled by resetting
    // the transition-property property dispatches an added notification and
    // then a removed notification.
    test(t => {
      var div =
        addDiv(t, { style: "transition: background-color 100s; " +
                           "background-color: yellow;" });
      var observer =
        setupSynchronousObserver(t,
                                 aOptions.subtree ? div.parentNode : div,
                                 aOptions.subtree);

      getComputedStyle(div).transitionProperty;
      div.style.backgroundColor = "lime";

      // The transition should cause the creation of a single Animation.
      var animations = div.getAnimations();
      assert_equals(animations.length, 1,
        "getAnimations().length after transition start");

      assert_equals_records(observer.takeRecords(),
        [{ added: animations, changed: [], removed: [] }],
        "records after transition start");

      // Cancel the transition by setting transition-property.
      div.style.transitionProperty = "none";
      getComputedStyle(div).transitionProperty;

      assert_equals_records(observer.takeRecords(),
        [{ added: [], changed: [], removed: animations }],
        "records after transition end");
    }, "single_transition_cancelled_property");

    // Test that starting a single transition that is cancelled by setting
    // style to the currently animated value dispatches an added
    // notification and then a removed notification.
    test(t => {
      // A long transition with a predictable value.
      var div =
        addDiv(t, { style: "transition: z-index 100s -51s; " +
                           "z-index: 10;" });
      var observer =
        setupSynchronousObserver(t,
                                 aOptions.subtree ? div.parentNode : div,
                                 aOptions.subtree);
      getComputedStyle(div).transitionProperty;
      div.style.zIndex = "100";

      // The transition should cause the creation of a single Animation.
      var animations = div.getAnimations();
      assert_equals(animations.length, 1,
        "getAnimations().length after transition start");

      assert_equals_records(observer.takeRecords(),
        [{ added: animations, changed: [], removed: [] }],
        "records after transition start");

      // Cancel the transition by setting the current animation value.
      let value = "83";
      assert_equals(getComputedStyle(div).zIndex, value,
        "half-way transition value");
      div.style.zIndex = value;
      getComputedStyle(div).transitionProperty;

      assert_equals_records(observer.takeRecords(),
        [{ added: [], changed: [], removed: animations }],
        "records after transition end");
    }, "single_transition_cancelled_value");

    // Test that starting a single transition that is cancelled by setting
    // style to a non-interpolable value dispatches an added notification
    // and then a removed notification.
    test(t => {
      var div =
        addDiv(t, { style: "transition: line-height 100s; " +
                           "line-height: 16px;" });
      var observer =
        setupSynchronousObserver(t,
                                 aOptions.subtree ? div.parentNode : div,
                                 aOptions.subtree);

      getComputedStyle(div).transitionProperty;
      div.style.lineHeight = "100px";

      // The transition should cause the creation of a single Animation.
      var animations = div.getAnimations();
      assert_equals(animations.length, 1,
        "getAnimations().length after transition start");

      assert_equals_records(observer.takeRecords(),
        [{ added: animations, changed: [], removed: [] }],
        "records after transition start");

      // Cancel the transition by setting line-height to a non-interpolable value.
      div.style.lineHeight = "normal";
      getComputedStyle(div).transitionProperty;

      assert_equals_records(observer.takeRecords(),
        [{ added: [], changed: [], removed: animations }],
        "records after transition end");
    }, "single_transition_cancelled_noninterpolable");

    // Test that starting a single transition and then reversing it
    // dispatches an added notification, then a simultaneous removed and
    // added notification, then a removed notification once finished.
    test(t => {
      var div =
        addDiv(t, { style: "transition: background-color 100s step-start; " +
                           "background-color: yellow;" });
      var observer =
        setupSynchronousObserver(t,
                                 aOptions.subtree ? div.parentNode : div,
                                 aOptions.subtree);

      getComputedStyle(div).transitionProperty;
      div.style.backgroundColor = "lime";

      var animations = div.getAnimations();

      // The transition should cause the creation of a single Animation.
      assert_equals(animations.length, 1,
        "getAnimations().length after transition start");

      var firstAnimation = animations[0];
      assert_equals_records(observer.takeRecords(),
        [{ added: [firstAnimation], changed: [], removed: [] }],
        "records after transition start");

      firstAnimation.currentTime = 50 * MS_PER_SEC;

      // Reverse the transition by setting the background-color back to its
      // original value.
      div.style.backgroundColor = "yellow";

      // The reversal should cause the creation of a new Animation.
      animations = div.getAnimations();
      assert_equals(animations.length, 1,
        "getAnimations().length after transition reversal");

      var secondAnimation = animations[0];

      assert_true(firstAnimation != secondAnimation,
        "second Animation should be different from the first");

      assert_equals_records(observer.takeRecords(),
        [{ added: [], changed: [firstAnimation], removed: [] },
         { added: [secondAnimation], changed: [], removed: [firstAnimation] }],
        "records after transition reversal");

      // Cancel the transition.
      div.style.transitionProperty = "none";
      getComputedStyle(div).transitionProperty;

      assert_equals_records(observer.takeRecords(),
        [{ added: [], changed: [], removed: [secondAnimation] }],
        "records after transition end");
    }, "single_transition_reversed");

    // Test that multiple transitions starting and ending on an element
    // at the same time get batched up into a single MutationRecord.
    test(t => {
      var div =
        addDiv(t, { style: "transition-duration: 100s; " +
                           "transition-property: color, background-color, line-height" +
                           "background-color: yellow; line-height: 16px" });
      var observer =
        setupSynchronousObserver(t,
                                 aOptions.subtree ? div.parentNode : div,
                                 aOptions.subtree);
      getComputedStyle(div).transitionProperty;

      div.style.backgroundColor = "lime";
      div.style.color = "blue";
      div.style.lineHeight = "24px";

      // The transitions should cause the creation of three Animations.
      var animations = div.getAnimations();
      assert_equals(animations.length, 3,
        "getAnimations().length after transition starts");

      assert_equals_records(observer.takeRecords(),
        [{ added: animations, changed: [], removed: [] }],
        "records after transition starts");

      assert_equals(animations.filter(p => p.playState == "running").length, 3,
         "number of running Animations");

      // Seek well into each animation.
      animations.forEach(p => p.currentTime = 50 * MS_PER_SEC);

      // Prepare the set of expected change MutationRecords, one for each
      // animation that was seeked.
      var seekRecords = animations.map(
        p => ({ added: [], changed: [p], removed: [] })
      );

      // Cancel one of the transitions by setting transition-property.
      div.style.transitionProperty = "background-color, line-height";

      var colorAnimation  = animations.filter(p => p.playState != "running");
      var otherAnimations = animations.filter(p => p.playState == "running");

      assert_equals(colorAnimation.length, 1,
        "number of non-running Animations after cancelling one");
      assert_equals(otherAnimations.length, 2,
        "number of running Animations after cancelling one");

      assert_equals_records(observer.takeRecords(),
        seekRecords.concat({ added: [], changed: [], removed: colorAnimation }),
        "records after color transition end");

      // Cancel the remaining transitions.
      div.style.transitionProperty = "none";
      getComputedStyle(div).transitionProperty;

      assert_equals_records(observer.takeRecords(),
        [{ added: [], changed: [], removed: otherAnimations }],
        "records after other transition ends");
    }, "multiple_transitions");

    // Test that starting a single animation that is cancelled by resetting
    // the animation-name property dispatches an added notification and
    // then a removed notification.
    test(t => {
      var div =
        addDiv(t, { style: "animation: anim 100s" });
      var observer =
        setupSynchronousObserver(t,
                                 aOptions.subtree ? div.parentNode : div,
                                 aOptions.subtree);

      // The animation should cause the creation of a single Animation.
      var animations = div.getAnimations();
      assert_equals(animations.length, 1,
        "getAnimations().length after animation start");

      assert_equals_records(observer.takeRecords(),
        [{ added: animations, changed: [], removed: [] }],
        "records after animation start");

      // Cancel the animation by setting animation-name.
      div.style.animationName = "none";
      getComputedStyle(div).animationName;

      assert_equals_records(observer.takeRecords(),
        [{ added: [], changed: [], removed: animations }],
        "records after animation end");
    }, "single_animation_cancelled_name");

    // Test that starting a single animation that is cancelled by updating
    // the animation-duration property dispatches an added notification and
    // then a removed notification.
    test(t => {
      var div =
        addDiv(t, { style: "animation: anim 100s" });
      var observer =
        setupSynchronousObserver(t,
                                 aOptions.subtree ? div.parentNode : div,
                                 aOptions.subtree);

      // The animation should cause the creation of a single Animation.
      var animations = div.getAnimations();
      assert_equals(animations.length, 1,
        "getAnimations().length after animation start");

      assert_equals_records(observer.takeRecords(),
        [{ added: animations, changed: [], removed: [] }],
        "records after animation start");

      // Advance the animation by a second.
      animations[0].currentTime += 1 * MS_PER_SEC;

      // Cancel the animation by setting animation-duration to a value less
      // than a second.
      div.style.animationDuration = "0.1s";
      getComputedStyle(div).animationName;

      assert_equals_records(observer.takeRecords(),
        [{ added: [], changed: animations, removed: [] },
         { added: [], changed: [], removed: animations }],
        "records after animation end");
    }, "single_animation_cancelled_duration");

    // Test that starting a single animation that is cancelled by updating
    // the animation-delay property dispatches an added notification and
    // then a removed notification.
    test(t => {
      var div =
        addDiv(t, { style: "animation: anim 100s" });
      var observer =
        setupSynchronousObserver(t,
                                 aOptions.subtree ? div.parentNode : div,
                                 aOptions.subtree);

      // The animation should cause the creation of a single Animation.
      var animations = div.getAnimations();
      assert_equals(animations.length, 1,
        "getAnimations().length after animation start");

      assert_equals_records(observer.takeRecords(),
        [{ added: animations, changed: [], removed: [] }],
        "records after animation start");

      // Cancel the animation by setting animation-delay.
      div.style.animationDelay = "-200s";
      getComputedStyle(div).animationName;

      assert_equals_records(observer.takeRecords(),
        [{ added: [], changed: [], removed: animations }],
        "records after animation end");
    }, "single_animation_cancelled_delay");

    // Test that starting a single animation that is cancelled by updating
    // the animation-iteration-count property dispatches an added notification
    // and then a removed notification.
    test(t => {
      // A short, repeated animation.
      var div =
        addDiv(t, { style: "animation: anim 0.5s infinite;" });
      var observer =
        setupSynchronousObserver(t,
                                 aOptions.subtree ? div.parentNode : div,
                                 aOptions.subtree);

      // The animation should cause the creation of a single Animation.
      var animations = div.getAnimations();
      assert_equals(animations.length, 1,
        "getAnimations().length after animation start");

      assert_equals_records(observer.takeRecords(),
        [{ added: animations, changed: [], removed: [] }],
        "records after animation start");

      // Advance the animation until we are past the first iteration.
      animations[0].currentTime += 1 * MS_PER_SEC;

      assert_equals_records(observer.takeRecords(),
        [{ added: [], changed: animations, removed: [] }],
        "records after seeking animations");

      // Cancel the animation by setting animation-iteration-count.
      div.style.animationIterationCount = "1";
      getComputedStyle(div).animationName;

      assert_equals_records(observer.takeRecords(),
        [{ added: [], changed: [], removed: animations }],
        "records after animation end");
    }, "single_animation_cancelled_iteration_count");

    // Test that updating an animation property dispatches a changed notification.
    [
      { name: "duration",  prop: "animationDuration",       val: "200s"    },
      { name: "timing",    prop: "animationTimingFunction", val: "linear"  },
      { name: "iteration", prop: "animationIterationCount", val: "2"       },
      { name: "direction", prop: "animationDirection",      val: "reverse" },
      { name: "state",     prop: "animationPlayState",      val: "paused"  },
      { name: "delay",     prop: "animationDelay",          val: "-1s"     },
      { name: "fill",      prop: "animationFillMode",       val: "both"    },
    ].forEach(aChangeTest => {
      test(t => {
        // Start a long animation.
        var div = addDiv(t, { style: "animation: anim 100s;" });
        var observer =
          setupSynchronousObserver(t,
                                   aOptions.subtree ? div.parentNode : div,
                                   aOptions.subtree);

        // The animation should cause the creation of a single Animation.
        var animations = div.getAnimations();
        assert_equals(animations.length, 1,
          "getAnimations().length after animation start");

        assert_equals_records(observer.takeRecords(),
          [{ added: animations, changed: [], removed: [] }],
          "records after animation start");

        // Change a property of the animation such that it keeps running.
        div.style[aChangeTest.prop] = aChangeTest.val;
        getComputedStyle(div).animationName;

        assert_equals_records(observer.takeRecords(),
          [{ added: [], changed: animations, removed: [] }],
          "records after animation change");

        // Cancel the animation.
        div.style.animationName = "none";
        getComputedStyle(div).animationName;

        assert_equals_records(observer.takeRecords(),
          [{ added: [], changed: [], removed: animations }],
          "records after animation end");
      }, `single_animation_change_${aChangeTest.name}`);
    });

    // Test that calling finish() on a pause-pending (but otherwise finished)
    // animation dispatches a changed notification.
    test(t => {
      var div =
        addDiv(t, { style: "animation: anim 100s forwards" });
      var observer =
        setupSynchronousObserver(t,
                                 aOptions.subtree ? div.parentNode : div,
                                 aOptions.subtree);

      // The animation should cause the creation of a single Animation.
      var animations = div.getAnimations();
      assert_equals(animations.length, 1,
        "getAnimations().length after animation start");

      assert_equals_records(observer.takeRecords(),
        [{ added: animations, changed: [], removed: [] }],
        "records after animation start");

      // Finish and pause.
      animations[0].finish();
      animations[0].pause();
      assert_true(animations[0].pending && animations[0].playState === "paused",
        "playState after finishing and calling pause()");

      // Call finish() again to abort the pause
      animations[0].finish();
      assert_equals(animations[0].playState, "finished",
        "playState after finishing again");

      // Wait for three MutationRecords for the Animation changes to
      // be delivered: one for each finish(), pause(), finish() operation.
      assert_equals_records(observer.takeRecords(),
        [{ added: [], changed: animations, removed: [] },
         { added: [], changed: animations, removed: [] },
         { added: [], changed: animations, removed: [] }],
        "records after finish(), pause(), finish()");

      // Cancel the animation.
      div.style = "";
      getComputedStyle(div).animationName;

      assert_equals_records(observer.takeRecords(),
        [{ added: [], changed: [], removed: animations }],
        "records after animation end");
    }, "finish_from_pause_pending");

    // Test that calling play() on a finished Animation that fills forwards
    // dispatches a changed notification.
    test(t => {
      // Animation with a forwards fill
      var div =
        addDiv(t, { style: "animation: anim 100s forwards" });
      var observer =
        setupSynchronousObserver(t,
                                 aOptions.subtree ? div.parentNode : div,
                                 aOptions.subtree);

      // The animation should cause the creation of a single Animation.
      var animations = div.getAnimations();
      assert_equals(animations.length, 1,
        "getAnimations().length after animation start");

      assert_equals_records(observer.takeRecords(),
        [{ added: animations, changed: [], removed: [] }],
        "records after animation start");

      // Seek to the end
      animations[0].finish();

      assert_equals_records(observer.takeRecords(),
        [{ added: [], changed: animations, removed: [] }],
        "records after finish()");

      // Since we are filling forwards, calling play() should produce a
      // change record since the animation remains relevant.
      animations[0].play();

      assert_equals_records(observer.takeRecords(),
        [{ added: [], changed: animations, removed: [] }],
        "records after play()");

      // Cancel the animation.
      div.style = "";
      getComputedStyle(div).animationName;

      assert_equals_records(observer.takeRecords(),
        [{ added: [], changed: [], removed: animations }],
        "records after animation end");
    }, "play_filling_forwards");

    // Test that calling pause() on an Animation dispatches a changed
    // notification.
    test(t => {
      var div =
        addDiv(t, { style: "animation: anim 100s" });
      var observer =
        setupSynchronousObserver(t,
                                 aOptions.subtree ? div.parentNode : div,
                                 aOptions.subtree);

      // The animation should cause the creation of a single Animation.
      var animations = div.getAnimations();
      assert_equals(animations.length, 1,
        "getAnimations().length after animation start");

      assert_equals_records(observer.takeRecords(),
        [{ added: animations, changed: [], removed: [] }],
        "records after animation start");

      // Pause
      animations[0].pause();

      assert_equals_records(observer.takeRecords(),
        [{ added: [], changed: animations, removed: [] }],
        "records after pause()");

      // Redundant pause
      animations[0].pause();

      assert_equals_records(observer.takeRecords(),
        [], "records after redundant pause()");

      // Cancel the animation.
      div.style = "";
      getComputedStyle(div).animationName;

      assert_equals_records(observer.takeRecords(),
        [{ added: [], changed: [], removed: animations }],
        "records after animation end");
    }, "pause");

    // Test that calling pause() on an Animation that is pause-pending
    // does not dispatch an additional changed notification.
    test(t => {
      var div =
        addDiv(t, { style: "animation: anim 100s" });
      var observer =
        setupSynchronousObserver(t,
                                 aOptions.subtree ? div.parentNode : div,
                                 aOptions.subtree);

      // The animation should cause the creation of a single Animation.
      var animations = div.getAnimations();
      assert_equals(animations.length, 1,
        "getAnimations().length after animation start");

      assert_equals_records(observer.takeRecords(),
        [{ added: animations, changed: [], removed: [] }],
        "records after animation start");

      // Pause
      animations[0].pause();

      // We are now pause-pending, but pause again
      animations[0].pause();

      assert_equals_records(observer.takeRecords(),
        [{ added: [], changed: animations, removed: [] }],
        "records after pause()");

      // Cancel the animation.
      div.style = "";
      getComputedStyle(div).animationName;

      assert_equals_records(observer.takeRecords(),
        [{ added: [], changed: [], removed: animations }],
        "records after animation end");
    }, "pause_while_pause_pending");

    // Test that calling play() on an Animation that is pause-pending
    // dispatches a changed notification.
    test(t => {
      var div =
        addDiv(t, { style: "animation: anim 100s" });
      var observer =
        setupSynchronousObserver(t,
                                 aOptions.subtree ? div.parentNode : div,
                                 aOptions.subtree);

      // The animation should cause the creation of a single Animation.
      var animations = div.getAnimations();
      assert_equals(animations.length, 1,
        "getAnimations().length after animation start");

      assert_equals_records(observer.takeRecords(),
        [{ added: animations, changed: [], removed: [] }],
        "records after animation start");

      // Pause
      animations[0].pause();

      // We are now pause-pending. If we play() now, we will abort the pause
      animations[0].play();

      assert_equals_records(observer.takeRecords(),
        [{ added: [], changed: animations, removed: [] },
        { added: [], changed: animations, removed: [] }],
                      "records after aborting a pause()");

      // Cancel the animation.
      div.style = "";
      getComputedStyle(div).animationName;

      assert_equals_records(observer.takeRecords(),
        [{ added: [], changed: [], removed: animations }],
        "records after animation end");
    }, "aborted_pause");

    // Test that calling play() on a finished Animation that does *not* fill
    // forwards dispatches an addition notification.
    test(t => {
      var div =
        addDiv(t, { style: "animation: anim 100s" });
      var observer =
        setupSynchronousObserver(t,
                                 aOptions.subtree ? div.parentNode : div,
                                 aOptions.subtree);

      // The animation should cause the creation of a single Animation.
      var animations = div.getAnimations();
      assert_equals(animations.length, 1,
        "getAnimations().length after animation start");

      assert_equals_records(observer.takeRecords(),
        [{ added: animations, changed: [], removed: [] }],
        "records after animation start");

      // Seek to the end
      animations[0].finish();

      assert_equals_records(observer.takeRecords(),
        [{ added: [], changed: [], removed: animations }],
        "records after finish()");

      // Since we are *not* filling forwards, calling play() is equivalent
      // to creating a new animation since it becomes relevant again.
      animations[0].play();

      assert_equals_records(observer.takeRecords(),
        [{ added: animations, changed: [], removed: [] }],
        "records after play()");

      // Cancel the animation.
      div.style = "";
      getComputedStyle(div).animationName;

      assert_equals_records(observer.takeRecords(),
        [{ added: [], changed: [], removed: animations }],
        "records after animation end");
    }, "play_after_finish");

  });

  test(t => {
    var div = addDiv(t);
    var observer = setupSynchronousObserver(t, div, true);

    var child = document.createElement("div");
    div.appendChild(child);

    var anim1 = div.animate({ marginLeft: [ "0px", "50px" ] },
                            100 * MS_PER_SEC);
    var anim2 = child.animate({ marginLeft: [ "0px", "100px" ] },
                              50 * MS_PER_SEC);
    assert_equals_records(observer.takeRecords(),
      [{ added: [anim1], changed: [], removed: [] },
       { added: [anim2], changed: [], removed: [] }],
      "records after animation is added");

    // After setting a new effect, we remove the current animation, anim1,
    // because it is no longer attached to |div|, and then remove the previous
    // animation, anim2. Finally, add back the anim1 which is in effect on
    // |child| now. In addition, we sort them by tree order and they are
    // batched.
    anim1.effect = anim2.effect;
    assert_equals_records(observer.takeRecords(),
      [{ added: [], changed: [], removed: [anim1] },       // div
       { added: [anim1], changed: [], removed: [anim2] }], // child
      "records after animation effects are changed");
  }, "set_effect_with_previous_animation");

  test(t => {
    var div = addDiv(t);
    var observer = setupSynchronousObserver(t, document, true);

    var anim = div.animate({ opacity: [ 0, 1 ] },
                           { duration: 100 * MS_PER_SEC });

    var newTarget = document.createElement("div");

    assert_equals_records(observer.takeRecords(),
      [{ added: [anim], changed: [], removed: [] }],
      "records after animation is added");

    anim.effect.target = null;
    assert_equals_records(observer.takeRecords(),
      [{ added: [], changed: [], removed: [anim] }],
      "records after setting null");

    anim.effect.target = div;
    assert_equals_records(observer.takeRecords(),
      [{ added: [anim], changed: [], removed: [] }],
      "records after setting a target");

    anim.effect.target = addDiv(t);
    assert_equals_records(observer.takeRecords(),
      [{ added: [], changed: [], removed: [anim] },
       { added: [anim], changed: [], removed: [] }],
      "records after setting a different target");
  }, "set_animation_target");

  test(t => {
    var div = addDiv(t);
    var observer = setupSynchronousObserver(t, div, true);

    var anim = div.animate({ opacity: [ 0, 1 ] },
                           { duration: 200 * MS_PER_SEC,
                             pseudoElement: '::before' });

    assert_equals_records(observer.takeRecords(),
      [{ added: [anim], changed: [], removed: [] }],
      "records after animation is added");

    anim.effect.updateTiming({ duration: 100 * MS_PER_SEC });
    assert_equals_records(observer.takeRecords(),
      [{ added: [], changed: [anim], removed: [] }],
      "records after duration is changed");

    anim.effect.updateTiming({ duration: 100 * MS_PER_SEC });
    assert_equals_records(observer.takeRecords(),
      [], "records after assigning same value");

    anim.currentTime = anim.effect.getComputedTiming().duration * 2;
    anim.finish();
    assert_equals_records(observer.takeRecords(),
      [{ added: [], changed: [], removed: [anim] }],
      "records after animation end");

    anim.effect.updateTiming({
      duration: anim.effect.getComputedTiming().duration * 3
    });
    assert_equals_records(observer.takeRecords(),
      [{ added: [anim], changed: [], removed: [] }],
      "records after animation restarted");

    anim.effect.updateTiming({ duration: "auto" });
    assert_equals_records(observer.takeRecords(),
      [{ added: [], changed: [], removed: [anim] }],
      "records after duration set \"auto\"");

    anim.effect.updateTiming({ duration: "auto" });
    assert_equals_records(observer.takeRecords(),
      [], "records after assigning same value \"auto\"");
  }, "change_duration_and_currenttime_on_pseudo_elements");

  test(t => {
    var div = addDiv(t);
    var observer = setupSynchronousObserver(t, div, false);

    var anim = div.animate({ opacity: [ 0, 1 ] },
                           { duration: 100 * MS_PER_SEC });
    var pAnim = div.animate({ opacity: [ 0, 1 ] },
                            { duration: 100 * MS_PER_SEC,
                              pseudoElement: "::before" });

    assert_equals_records(observer.takeRecords(),
      [{ added: [anim], changed: [], removed: [] }],
      "records after animation is added");

    anim.finish();
    pAnim.finish();

    assert_equals_records(observer.takeRecords(),
      [{ added: [], changed: [], removed: [anim] }],
      "records after animation is finished");
  }, "exclude_animations_targeting_pseudo_elements");
}

W3CTest.runner.expectAssertions(0, 12); // bug 1189015
runTest();

</script>