<!doctype html>
<script src="/resources/testharness.js"></script>
<script src="/resources/testharnessreport.js"></script>
<body>
<script>
promise_test(async t => {
  let intercept_resolve;
  navigation.addEventListener("navigate", e => {
    e.intercept({ handler: () => new Promise(resolve => intercept_resolve = resolve),
                  focusReset: "after-transition" });
  }, { once: true });

  const button = document.body.appendChild(document.createElement("button"));
  const button2 = document.body.appendChild(document.createElement("button"));
  button2.tabIndex = 0;
  t.add_cleanup(() => {
    button.remove();
    button2.remove();
  });

  assert_equals(document.activeElement, document.body, "Start on body");
  button.focus();
  assert_equals(document.activeElement, button, "focus() worked");

  const finished = navigation.navigate("#1").finished;

  let onfocus_called = false;
  document.body.onfocus = onfocus_called = true;
  button.remove();
  assert_equals(document.activeElement, document.body, "Removing the element reset focus");
  assert_true(onfocus_called);

  document.body.onfocus = t.unreached_func("onfocus shouldn't fire a second time due to focus reset");
  intercept_resolve();
  await finished;
  assert_equals(document.activeElement, document.body, "Focus remains on document.body after promise fulfills");
  await new Promise(resolve => t.step_timeout(resolve, 10));
}, "");
</script>
</body>
