<!doctype html>
<meta charset=utf-8>
<title>Canceling a CSS transition</title>
<link rel="help" href="https://drafts.csswg.org/css-transitions/#starting">
<!-- TODO: Add a more specific link for this once it is specified. -->
<link rel="help" href="https://drafts.csswg.org/css-transitions-2/#csstransition">
<script src="/resources/testharness.js"></script>
<script src="/resources/testharnessreport.js"></script>
<script src="support/helper.js"></script>
<div id="log"></div>
<script>
'use strict';

promise_test(async t => {
  const div = addDiv(t, { style: 'margin-left: 0px' });
  getComputedStyle(div).marginLeft;

  div.style.transition = 'margin-left 100s';
  div.style.marginLeft = '1000px';

  const transition = div.getAnimations()[0];
  await transition.ready;
  await waitForFrame();

  assert_not_equals(getComputedStyle(div).marginLeft, '1000px',
                    'transform style is animated before canceling');
  transition.cancel();
  assert_equals(getComputedStyle(div).marginLeft, div.style.marginLeft,
                'transform style is no longer animated after canceling');
}, 'Animated style is cleared after canceling a running CSS transition');

promise_test(async t => {
  const div = addDiv(t, { style: 'margin-left: 0px' });
  getComputedStyle(div).marginLeft;

  div.style.transition = 'margin-left 100s';
  div.style.marginLeft = '1000px';

  const transition = div.getAnimations()[0];
  await transition.ready;

  transition.cancel();
  assert_equals(getComputedStyle(div).marginLeft, '1000px',
                'margin-left style is not animated after canceling');
  transition.play();
  assert_equals(getComputedStyle(div).marginLeft, '0px',
                'margin-left style is animated after re-starting transition');

  await transition.ready;

  assert_equals(transition.playState, 'running',
                'Transition succeeds in running after being re-started');
}, 'After canceling a transition, it can still be re-used');

promise_test(async t => {
  const div = addDiv(t, { style: 'margin-left: 0px' });
  getComputedStyle(div).marginLeft;

  div.style.transition = 'margin-left 100s';
  div.style.marginLeft = '1000px';

  const transition = div.getAnimations()[0];
  await transition.ready;

  transition.finish();
  transition.cancel();
  assert_equals(getComputedStyle(div).marginLeft, '1000px',
                'margin-left style is not animated after canceling');
  transition.play();
  assert_equals(getComputedStyle(div).marginLeft, '0px',
                'margin-left style is animated after re-starting transition');

  await transition.ready;

  assert_equals(transition.playState, 'running',
                'Transition succeeds in running after being re-started');
}, 'After canceling a finished transition, it can still be re-used');

test(t => {
  const div = addDiv(t, { style: 'margin-left: 0px' });
  getComputedStyle(div).marginLeft;

  div.style.transition = 'margin-left 100s';
  div.style.marginLeft = '1000px';

  const transition = div.getAnimations()[0];
  transition.cancel();
  assert_equals(getComputedStyle(div).marginLeft, '1000px',
                'margin-left style is not animated after canceling');

  // Trigger a change to a transition property and check that this
  // doesn't cause the animation to become live again
  div.style.transitionDuration = '200s';
  getComputedStyle(div).marginLeft;
  assert_equals(getComputedStyle(div).marginLeft, '1000px',
                'margin-left style is still not animated after updating'
                + ' transition-duration');
  assert_equals(transition.playState, 'idle',
                'Transition is still idle after updating transition-duration');
}, 'After canceling a transition, updating transition properties doesn\'t make'
   + ' it live again');

promise_test(async t => {
  const div = addDiv(t, { style: 'margin-left: 0px' });
  getComputedStyle(div).marginLeft;

  div.style.transition = 'margin-left 100s';
  div.style.marginLeft = '1000px';

  const transition = div.getAnimations()[0];
  await transition.ready;

  assert_equals(transition.playState, 'running');
  div.style.display = 'none';

  await waitForFrame();

  assert_equals(transition.playState, 'idle');
  assert_equals(getComputedStyle(div).marginLeft, '1000px');
}, 'Setting display:none on an element cancels its transitions');

promise_test(async t => {
  const parentDiv = addDiv(t);
  const childDiv = document.createElement('div');
  parentDiv.appendChild(childDiv);
  childDiv.setAttribute('style', 'margin-left: 0px');

  getComputedStyle(childDiv).marginLeft;

  childDiv.style.transition = 'margin-left 100s';
  childDiv.style.marginLeft = '1000px';

  const transition = childDiv.getAnimations()[0];
  await transition.ready;

  assert_equals(transition.playState, 'running');
  parentDiv.style.display = 'none';
  await waitForFrame();

  assert_equals(transition.playState, 'idle');
  assert_equals(getComputedStyle(childDiv).marginLeft, '1000px');
}, 'Setting display:none cancels transitions on a child element');

promise_test(async t => {
  const div = addDiv(t, { style: 'margin-left: 0px' });
  getComputedStyle(div).marginLeft;

  div.style.transition = 'margin-left 100s';
  div.style.marginLeft = '1000px';

  const transition = div.getAnimations()[0];
  await transition.ready;

  assert_equals(transition.playState, 'running');
  // Set an unrecognized property value
  div.style.transitionProperty = 'none';
  getComputedStyle(div).marginLeft;
  await waitForFrame();

  assert_equals(transition.playState, 'idle');
  assert_equals(getComputedStyle(div).marginLeft, '1000px');
}, 'Removing a property from transition-property cancels transitions on that '+
   'property');

promise_test(async t => {
  const div = addDiv(t, { style: 'margin-left: 0px' });
  getComputedStyle(div).marginLeft;

  div.style.transition = 'margin-left 100s';
  div.style.marginLeft = '1000px';

  const transition = div.getAnimations()[0];
  await transition.ready;

  assert_equals(transition.playState, 'running');
  div.style.transition = 'margin-left 10s -10s'; // combined duration is zero

  // Note that simply setting the combined duration to zero is not enough to
  // cancel the transition. We must also update the end value so that the,
  // "the end value of the running transition is not equal to the value of the
  // property in the after-change style" condition is true.
  //
  // (And note that the zero combined duration is not strictly necessary to
  // cancel the original transition--but it does ensure another transition is
  // not generated in its place.)

  div.style.marginLeft = '2000px';
  getComputedStyle(div).marginLeft;
  await waitForFrame();

  assert_equals(transition.playState, 'idle');
  assert_equals(getComputedStyle(div).marginLeft, '2000px');
}, 'Setting zero combined duration');

promise_test(async t => {
  const div = addDiv(t, { style: 'margin-left: 0px' });
  getComputedStyle(div).marginLeft;

  div.style.transition = 'margin-left 100s';
  div.style.marginLeft = '1000px';

  const transition = div.getAnimations()[0];
  await transition.ready;

  assert_equals(transition.playState, 'running');
  div.style.marginLeft = '2000px';
  getComputedStyle(div).marginLeft;
  await waitForFrame();

  assert_equals(transition.playState, 'idle');
}, 'Changing style to another interpolable value cancels the original ' +
   'transition');

promise_test(async t => {
  const div = addDiv(t, { style: 'margin-left: 0px' });
  getComputedStyle(div).marginLeft;

  div.style.transition = 'margin-left 100s';
  div.style.marginLeft = '1000px';

  const transition = div.getAnimations()[0];
  await transition.ready;

  assert_equals(transition.playState, 'running');
  div.style.marginLeft = 'auto';
  getComputedStyle(div).marginLeft;
  await waitForFrame();

  assert_equals(div.getAnimations().length, 0,
                'There should be no transitions');
  assert_equals(transition.playState, 'idle');
}, 'An after-change style value can\'t be interpolated');

promise_test(async t => {
  const div = addDiv(t, { style: 'margin-left: 0px' });
  getComputedStyle(div).marginLeft;

  div.style.transition = 'margin-left 100s';
  div.style.marginLeft = '1000px';

  const transition = div.getAnimations()[0];
  await transition.ready;

  assert_equals(transition.playState, 'running');
  div.style.marginLeft = '0px';
  getComputedStyle(div).marginLeft;
  await waitForFrame();

  assert_equals(transition.playState, 'idle');
}, 'Reversing a running transition cancels the original transition');

</script>