css/css-pseudo/marker-animate.html

<!DOCTYPE html>
<meta charset="utf-8">
<title>CSS Pseudo-Elements Test: Reverted styles for ::marker</title>
<link rel="help" href="https://drafts.csswg.org/css-pseudo-4/#marker-pseudo">
<link rel="help" href="https://drafts.csswg.org/web-animations-1/">
<link rel="author" title="Oriol Brufau" href="mailto:obrufau@igalia.com">
<meta name="assert" content="This test checks that ::marker can be animated with Web Animations, but only the supported properties." />
<div id="log"></div>
<ul>
  <li id="target">list item</li>
</ul>
<script src="/resources/testharness.js"></script>
<script src="/resources/testharnessreport.js"></script>
<script>
const target = document.getElementById("target");
const cs = getComputedStyle(target, "::marker");
const options = {
  pseudoElement: "::marker",
  duration: 2,
  delay: -1,
};

// 'color' applies to ::marker so it should be animatable
test(function() {
  const anim = target.animate([
    {color: "rgb(0, 100, 200)"},
    {color: "rgb(200, 0, 100)"},
  ], options);
  this.add_cleanup(() => anim.cancel());
  assert_equals(cs.color, "rgb(100, 50, 150)", "color");
}, "'color' animation");

// 'opacity' doesn't apply to ::marker so it shouldn't be animatable
test(function() {
  const anim = target.animate([
    {opacity: .2},
    {opacity: .8},
  ], options);
  this.add_cleanup(() => anim.cancel());
  assert_equals(cs.opacity, "1", "opacity");
}, "'opacity' animation");

// When both 'color' and 'opacity' are specified, only the former should be animated.
test(function() {
  const anim = target.animate([
    {
      color: "rgb(0, 100, 200)",
      opacity: .2,
    },
    {
      color: "rgb(200, 0, 100)",
      opacity: .8,
    },
  ], options);
  this.add_cleanup(() => anim.cancel());
  assert_equals(cs.color, "rgb(100, 50, 150)", "color");
  assert_equals(cs.opacity, "1", "opacity");
}, "'color' + 'opacity' animation");
</script>