navigation-api/navigate-event/navigation-traverseTo-same-document-preventDefault-multiple-windows.html

<!doctype html>
<script src="/resources/testharness.js"></script>
<script src="/resources/testharnessreport.js"></script>
<iframe id="i" src="/common/blank.html"></iframe>
<script>
promise_test(async t => {
  // Wait for after the load event so that the navigation doesn't get converted
  // into a replace navigation.
  await new Promise(resolve => window.onload = () => t.step_timeout(resolve, 0));
  await navigation.navigate("#").finished;
  await i.contentWindow.navigation.navigate("#").finished;
  assert_equals(navigation.entries().length, 2);
  assert_equals(i.contentWindow.navigation.entries().length, 2);
  assert_equals(navigation.currentEntry.index, 1);
  assert_equals(i.contentWindow.navigation.currentEntry.index, 1);

  navigation.onnavigate = e => e.preventDefault();
  i.contentWindow.navigation.onnavigate = t.unreached_func("navigate event should not fire in the iframe, because the traversal was cancelled in the top window");
  await promise_rejects_dom(t, "AbortError", navigation.traverseTo(navigation.entries()[0].key).finished);
  assert_equals(navigation.currentEntry.index, 1);
  assert_equals(i.contentWindow.navigation.currentEntry.index, 1);
}, "navigation.traverseTo() - if a top window cancels the traversal, any iframes should not fire navigate");
</script>