navigation-api/navigate-event/navigate-navigation-back-same-document-in-iframe.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));

  let target_key = i.contentWindow.navigation.currentEntry.key;
  let target_id = i.contentWindow.navigation.currentEntry.id;
  await i.contentWindow.navigation.navigate("#").finished;
  assert_true(i.contentWindow.navigation.canGoBack);

  i.contentWindow.navigation.onnavigate = e => {
    assert_equals(e.navigationType, "traverse");
    assert_false(e.cancelable, "traversals in iframes should never be cancelable");
    assert_true(e.canIntercept);
    assert_false(e.userInitiated);
    assert_true(e.hashChange);
    assert_equals(e.downloadRequest, null);
    assert_equals(new URL(e.destination.url).hash, "");
    assert_true(e.destination.sameDocument);
    assert_equals(e.destination.key, target_key);
    assert_equals(e.destination.id, target_id);
    assert_equals(e.destination.index, 0);
    assert_equals(e.formData, null);
    assert_equals(e.info, "hi");
  }
  await i.contentWindow.navigation.back({ info: "hi" }).finished;
}, "navigate event for navigation.back() - same-document in an iframe");
</script>