chromium/third_party/blink/web_tests/external/wpt/css/css-view-transitions/style-inheritance.html

<!DOCTYPE html>
<html>
<title>View transitions: ensure correct style inheritance for pseudo tree</title>
<link rel="help" href="https://drafts.csswg.org/css-view-transitions-1/">
<link rel="author" href="mailto:[email protected]">

<script src="/resources/testharness.js"></script>
<script src="/resources/testharnessreport.js"></script>

<style>
::view-transition {
  background-color: red;
}

::view-transition-group(*) {
  background-color: inherit;
  color: blue;
  animation-duration: 0.321s;
}

::view-transition-image-pair(*) {
  color: inherit;
  overflow-x: clip;
}

::view-transition-old(*), ::view-transition-new(*) {
  overflow-x: inherit;
}
</style>

<script>
promise_test(() => {
  assert_implements(document.startViewTransition, "Missing document.startViewTransition");
  return new Promise(async (resolve, reject) => {
    let transition = document.startViewTransition();
    transition.ready.then(() => {
      assert_equals(getComputedStyle(document.documentElement, "::view-transition").backgroundColor, "rgb(255, 0, 0)", "::view-transition");

      assert_equals(getComputedStyle(document.documentElement, "::view-transition-group(root)").backgroundColor, "rgb(255, 0, 0)", "group");
      assert_equals(getComputedStyle(document.documentElement, "::view-transition-group(root)").color, "rgb(0, 0, 255)", "group");
      assert_equals(getComputedStyle(document.documentElement, "::view-transition-group(root)").animationDuration, "0.321s", "group");

      assert_equals(getComputedStyle(document.documentElement, "::view-transition-image-pair(root)").color, "rgb(0, 0, 255)", "wrapper");
      assert_equals(getComputedStyle(document.documentElement, "::view-transition-image-pair(root)").overflowX, "clip", "wrapper");
      assert_equals(getComputedStyle(document.documentElement, "::view-transition-image-pair(root)").animationDuration, "0.321s", "wrapper");

      assert_equals(getComputedStyle(document.documentElement, "::view-transition-old(root)").overflowX, "clip", "outgoing");
      assert_equals(getComputedStyle(document.documentElement, "::view-transition-old(root)").animationDuration, "0.321s", "outgoing");
      assert_equals(getComputedStyle(document.documentElement, "::view-transition-new(root)").overflowX, "clip", "incoming");
      assert_equals(getComputedStyle(document.documentElement, "::view-transition-new(root)").animationDuration, "0.321s", "incoming");
    });
    await transition.finished;
    resolve();
  });
}, "style inheritance of pseudo elements");
</script>