chromium/third_party/blink/web_tests/wpt_internal/display-lock/css-content-visibility/accessibility/content-visibility-accessibility-008.html

<!doctype HTML>
<html>
<meta charset="utf8">
<title>Content Visibility: accessibility</title>
<link rel="author" title="Vladimir Levin" href="mailto:[email protected]">
<link rel="help" href="https://github.com/WICG/display-locking">
<meta name="assert" content="content-visibility hidden subtree is not exposed to accessibility when added">

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

<style>
.hidden {
  content-visibility: hidden;
}
</style>
<div id="container">
  <div role="group" id="target" aria-labelledby="target_label">
    target
    <div id="child">
      child
    </div>
    <div id="target_label">Label</div>
  </div>
</div>

<script>
function axElementById(id) {
  return accessibilityController.accessibleElementById(id);
}

async_test((t) => {
  let target = document.getElementById("target");
  let axTarget = axElementById("target");
  t.step(() => { assert_false(axTarget.isIgnored); });
  t.step(() => { assert_equals(axTarget.childrenCount, 3, "When unlocked, nodes in hidden subtree are not ignored"); });
  t.step(() => { assert_equals(axTarget.name, "Label"); });
  for (let i = 0; i < axTarget.childrenCount; ++i) {
    const axChild = axTarget.childAtIndex(i);
    t.step(() => assert_false(axChild.isIgnored));
  }

  target.classList.add("hidden");
  requestAnimationFrame(() => requestAnimationFrame(() => {
    // The ax object for #target got replaced since the layout object changed, so use the new ax object.
    axTarget = axElementById("target");
    axTarget.childrenCount;  // Touch children to cause invalidations. Only necessary in web tests. Normally serializer does this.
    t.step(() => { assert_false(axTarget.isIgnored); });
    // Note that text nodes are marked ignored but still kept in the tree, because they might be
    // needed for accname calculation, as is the target of the aria-labelledby relation.
    t.step(() => { assert_equals(axTarget.childrenCount, 1, "When locked, nodes in hidden subtree are ignored"); });
    t.step(() => { assert_equals(axTarget.name, "Label"); });
    for (let i = 0; i < axTarget.childrenCount; ++i) {
      const axChild = axTarget.childAtIndex(i);
      t.step(() => assert_true(axChild.isIgnored));
    }
    t.done();
  }));
}, "When hidden is added, nodes in non-activatable tree are not exposed to accessibility tree");
</script>