declarative-shadow-dom-repeats-2.html

<!DOCTYPE html>
<title>Duplicate declarative shadow trees</title>
<script src=/resources/testharness.js></script>
<script src=/resources/testharnessreport.js></script>

<div id=multiple1>
  <template shadowrootmode=open>1</template>
  <template shadowrootmode=open>2</template>
  <template shadowrootmode=open>3</template>
</div>

<div id=multiple2>
  <template shadowrootmode=closed>1</template>
  <template shadowrootmode=closed>2</template>
  <template shadowrootmode=open>3</template>
</div>

<script>
test((t) => {
  t.add_cleanup(() => {
    multiple1.remove();
    multiple2.remove();
  });
  let shadow = multiple1.shadowRoot;
  assert_true(!!shadow,'Remaining shadow root should be open');
  assert_equals(shadow.textContent,"1");
  assert_equals(multiple1.childElementCount, 2);
  assert_equals(multiple1.firstElementChild.content.textContent, "2");
  assert_equals(multiple1.lastElementChild.content.textContent, "3");
  shadow = multiple2.shadowRoot;
  assert_false(!!shadow,'Remaining shadow root should be closed');
  assert_equals(multiple2.childElementCount, 2);
  assert_equals(multiple2.firstElementChild.content.textContent, "2");
  assert_equals(multiple2.lastElementChild.content.textContent, "3");
},'Repeated declarative shadow roots keep only the first');
</script>

chromium/third_party/blink/web_tests/external/wpt/shadow-dom/declarative/declarative-shadow-dom-repeats-2.html