chromium/third_party/blink/web_tests/external/wpt/shadow-dom/declarative/script-access.html

<!DOCTYPE html>
<title>Declarative Shadow DOM</title>
<link rel='author' href='mailto:[email protected]'>
<link rel='help' href='https://github.com/whatwg/dom/issues/831'>
<script src='/resources/testharness.js'></script>
<script src='/resources/testharnessreport.js'></script>

<body>
<script>
let templatesSeen = 0;

function myObserver(mutationsList, observer) {
  document.querySelectorAll('.host').forEach(n => {
    templatesSeen++;
    n.className = 'done';
    switch (n.id) {
      case 'openhost':
      case 'closedhost':
        assert_equals(n.querySelector('template'),null,'No template ever for streaming declarative Shadow DOM');
        assert_equals(n.innerHTML, "", 'Declarative shadow host innerHTML should be empty - all content is inside shadow');
        break;
      case 'noroot':
        const template = n.querySelector('template');
        assert_true(!!template,'Regular template should still be present');
        // Make sure adding 'shadowrootmode' attribute doesn't trigger a shadow root,
        // even if added before parsing completes.
        template.setAttribute('shadowrootmode','open');
        assert_not_equals(template.content, null, 'Regular template should have content, even after adding shadowrootmode attribute');
        assert_not_equals(template.innerHTML, "", 'Regular template should have innerHTML, even after adding shadowrootmode attribute');
        break;
      default:
        assert_unreached('Unrecognized template');
    }
  });
}
const observer = new MutationObserver(myObserver);
observer.observe(document.body, { childList: true, subtree: true });
assert_equals(templatesSeen, 0, 'No mutations yet');
</script>

<div id=openhost class=host><template shadowrootmode=open>
  <slot></slot>
  <!-- Ensure observer runs at this point (https://github.com/web-platform-tests/wpt/issues/35393) -->
  <script> // some content, which shouldn't be necessary </script>
</template></div>

<div id=closedhost class=host><template shadowrootmode=closed>
  <slot></slot>
  <!-- Ensure observer runs at this point (https://github.com/web-platform-tests/wpt/issues/35393) -->
  <script> // some content, which shouldn't be necessary </script>
</template></div>

<div id=noroot class=host><template>
  <slot></slot>
  <!-- Ensure observer runs at this point (https://github.com/web-platform-tests/wpt/issues/35393) -->
  <script> // some content, which shouldn't be necessary </script>
</template></div>

<script>
test(t => {
  t.add_cleanup(function() { observer.disconnect(); });

  assert_equals(templatesSeen, 3);

  // Open shadow root
  let host = document.querySelector('#openhost');
  assert_equals(host.querySelector('template'), null, 'No template nodes');
  assert_true(!!host.shadowRoot, 'Shadow root should exist');

  // Closed shadow root
  host = document.querySelector('#closedhost');
  assert_equals(host.querySelector('template'), null, 'No template nodes');
  assert_true(!host.shadowRoot, 'Closed shadow root (can\'t detect)');

  // No shadow root
  host = document.querySelector('#noroot');
  assert_true(!!host.querySelector('template'), 'Template node still present for invalid shadowrootmode value');
  assert_true(!host.shadowRoot, 'No shadow root');
},'Streaming Declarative Shadow DOM: template .content() should be null');
</script>


<script>
let synchronous_events_received = new Set();
function synchronousHandler(e) {
  synchronous_events_received.add(e.type);
}
const sync_events = ["DOMAttrModified","DOMAttributeNameChanged","DOMCharacterDataModified",
  "DOMElementNameChanged","DOMNodeInserted","DOMNodeInsertedIntoDocument","DOMNodeRemoved",
  "DOMNodeRemovedFromDocument","DOMSubtreeModified"];
function addSyncObserver(evt) {
  window.addEventListener(evt, synchronousHandler, true);
}
function removeSyncObserver(evt) {
  window.removeEventListener(evt, synchronousHandler, true);
}
sync_events.forEach(e => addSyncObserver(e));
</script>

<div id=synchost1>
  <template shadowrootmode=open>
    <div class=foo>content</div>
    <slot></slot>
  </template>
</div>

<div id=synchost2>
  <template shadowrootmode=closed>
    <div class=foo>content</div>
    <slot></slot>
  </template>
</div>

<script>
test(t => {
  t.add_cleanup(function() { sync_events.forEach(e => removeSyncObserver(e)) });
  assert_true(!synchronous_events_received.size,`Synchronous mutation events fired: ${Array.from(synchronous_events_received)}`);
},'Synchronous mutation events should not be fired during streaming declarative shadow DOM parsing');
</script>