chromium/third_party/blink/web_tests/wpt_internal/display-lock/css-content-visibility/accessibility/content-visibility-accessibility-001.html

<!doctype HTML>
<html>
<meta charset="utf8">
<title>Content Visibility: accessibility</title>
<link rel="author" title="Rakina Zata Amni" href="mailto:[email protected]">
<link rel="help" href="https://github.com/WICG/display-locking">
<meta name="assert" content="content-visibility auto subtree is exposed to accessibility">

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

<style>
.auto {
  content-visibility: auto;
}
</style>
<div id=spacer style="height: 3000px"></div>
<div id="container">
  <div role="group" id="target" class=auto aria-labelledby="target_label">
    target
    <div id="child">
      child
    </div>
    <div id="displayNone" style="display:none;">
      display:none text
    </div>
    <div id="hidden" style="visibility:hidden;">
      hidden text
    </div>
    <div id="target_label">Label</div>
  </div>
</div>

<script>

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

async_test((t) => {
  const target = document.getElementById("target");
  let axTarget = axElementById("target");
  t.step(() => { assert_false(axTarget.isIgnored); });

  // Expect 9 children: 5 text nodes ("target" text and whitespace between the divs) and 4 div children.
  // This is because #target is locked, and thus is saved as an AXNodeObject instead of an AXLayoutObject,
  // so we have the separate <newline> text children because AXNodeObject does not do whitespace
  // collapsing (though this might change in the future).
  // TODO(rakina): Make display:none, visiblity:hidden be ignored/not included in tree even when
  // display target, and make sure whitespace collapsing happen.
  t.step(() => { assert_equals(axTarget.childrenCount, 9, "Children count when locked"); });

  // These children are special because their "isVisible" should be false.
  const displayNoneIndex = 3;
  t.step(() => { assert_equals(axTarget.childAtIndex(displayNoneIndex), axElementById("displayNone"));});
  const visibilityHiddenIndex = 5;
  t.step(() => { assert_equals(axTarget.childAtIndex(visibilityHiddenIndex), axElementById("hidden"));});

  // Check all children are not ignored, and visibility:hidden & display:none child are marked as not visible.
  for (let i = 0; i < axTarget.childrenCount; ++i) {
    const axChild = axTarget.childAtIndex(i);
    t.step(() => { assert_false(axChild.isIgnored, "After acquire, isIgnored is false on child #" + i); });
    t.step(() => { assert_true(axChild.isVisible, "After acquire, isVisible is false on child #" + i); });
  }

  // Check that nodes in content-visibility:auto are available for aria-labelledby.
  t.step(() => { assert_equals(axTarget.name, "Label"); });

  // Remove content-visibility and force a layout recalc, causing #target to get unlocked.
  target.classList.remove("auto");
  requestAnimationFrame(() => requestAnimationFrame(() => {
    target.getBoundingClientRect();
    axTarget = axElementById("target");

    // Now #target is not locked, expect 5 children ("target" text node, 4 divs).
    // This is the same as it would be if content-visibility had never been used.
    t.step(() => { assert_equals(axTarget.childrenCount, 3, "Children count when not locked"); });

    for (let i = 0; i < axTarget.childrenCount; ++i) {
      const axChild = axTarget.childAtIndex(i);
      if (axChild == axElementById("hidden") || axChild == axElementById("displayNone")) {
        t.step(() => { assert_true(axChild.isIgnored, "After commit, isIgnored is true on child #" + i); });
        t.step(() => { assert_false(axChild.isVisible, "After commit, isVisible is false on child #" + i); });
      } else if (i == 0 || axChild == axElementById("child") || axChild == axElementById("target_label")) {
        t.step(() => { assert_false(axChild.isIgnored, "After update, isIgnored is false on child #" + i); });
        t.step(() => { assert_true(axChild.isVisible, "After commit, isVisible is true on child #" + i); });
      } else {
        // These are the whitespace nodes
        t.step(() => { assert_true(axChild.isIgnored, "After update, isIgnored is true on child #" + i); });
      }
    }

    // Check that nodes in content-visibility:auto are available for aria-labelledby.
    t.step(() => assert_equals(axTarget.name, "Label"));
    t.done();
  }));
}, "Nodes in a content-visibility auto tree are exposed to accessibility tree");
</script>