| 12
 3
 4
 5
 6
 7
 8
 9
 10
 11
 12
 13
 14
 15
 16
 17
 18
 19
 20
 21
 22
 23
 24
 25
 26
 27
 28
 29
 30
 31
 32
 33
 34
 35
 36
 37
 38
 39
 40
 41
 42
 43
 44
 45
 46
 47
 48
 49
 50
 51
 52
 53
 54
 55
 56
 57
 58
 59
 60
 61
 62
 63
 64
 65
 66
 67
 68
 69
 70
 71
 72
 73
 74
 75
 76
 77
 78
 79
 80
 81
 82
 83
 84
 85
 86
 87
 88
 89
 90
 91
 92
 93
 94
 95
 96
 97
 98
 99
 100
 101
 102
 103
 104
 105
 106
 107
 108
 109
 110
 111
 112
 113
 114
 115
 116
 117
 118
 119
 120
 121
 122
 123
 124
 125
 126
 127
 
 | <!doctype html>
<html>
<head>
<meta charset=utf-8>
<title>CSS Transitions Test: Transitions do not run for an element that is not being rendered</title>
<link rel="help" title="Starting transitions"
  href="https://drafts.csswg.org/css-transitions/#starting">
<script src="/resources/testharness.js" type="text/javascript"></script>
<script src="/resources/testharnessreport.js" type="text/javascript"></script>
<script src="./support/helper.js" type="text/javascript"></script>
</head>
<body>
<div id="log"></div>
<script>
promise_test(async t => {
  // Create element that is not rendered
  const div = addDiv(t, {
    style:
      'transition: background-color 100s;' +
      'background-color: red;' +
      'display: none',
  });
  // Attach event listeners
  div.addEventListener(
    'transitionrun',
    t.step_func(() => {
      assert_unreached('transitionrun event should not be fired');
    })
  );
  // Resolve before-change style
  getComputedStyle(div).backgroundColor;
  // Set up and resolve after-change style
  div.style.backgroundColor = 'green';
  getComputedStyle(div).backgroundColor;
  // There should be no events received for the triggered transition.
  await waitForFrame();
  await waitForFrame();
}, 'Transitions do not run on an element not being rendered');
test(t => {
  // Create element that is not rendered
  const div = addDiv(t, {
    style:
      'transition: background-color 100s;' +
      'background-color: red;' +
      'display: none',
  });
  // Resolve before-change style
  getComputedStyle(div).backgroundColor;
  // Make it rendered
  div.style.display = 'block';
  // Set up and resolve after-change style
  div.style.backgroundColor = 'green';
  getComputedStyle(div).backgroundColor;
  // We should have jumped immediately to the after-change style rather than
  // transitioning to it.
  assert_equals(
    getComputedStyle(div).backgroundColor,
    'rgb(0, 128, 0)',
    'No transition should run'
  );
}, 'Transitions do not run for an element newly rendered');
promise_test(async t => {
  // Create element
  const div = addDiv(t, {
    style: 'transition: background-color 100s; background-color: red',
  });
  // Attach event listeners
  div.addEventListener('transitionrun', t.step_func(() => {
    assert_unreached('transitionrun event should not be fired');
  }));
  // Resolve before-change style
  getComputedStyle(div).backgroundColor;
  // Set up after-change style
  div.style.backgroundColor = 'green';
  // But make the element non-rendered
  div.style.display = 'none';
  // There should be no events received for the triggered transition.
  await waitForFrame();
  await waitForFrame();
}, 'Transitions do not run for an element newly made not rendered');
promise_test(async t => {
  // Create element
  const div = addDiv(t, {
    style: 'transition: background-color 100s; background-color: red',
  });
  // Attach event listeners
  const eventWatcher = new EventWatcher(t, div, [
    'transitionrun',
    'transitioncancel',
  ]);
  // Trigger transition
  getComputedStyle(div).backgroundColor;
  div.style.backgroundColor = 'green';
  getComputedStyle(div).backgroundColor;
  await eventWatcher.wait_for('transitionrun');
  // Make the element no longer rendered
  div.style.display = 'none';
  await eventWatcher.wait_for('transitioncancel');
}, 'Transitions are canceled when an element is no longer rendered');
</script>
</body>
</html>
 |