navigation-api/per-entry-events/dispose-for-full-session-history.tentative.html

<!doctype html>
<script src="/resources/testharness.js"></script>
<script src="/resources/testharnessreport.js"></script>
<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(r => window.onload = () => t.step_timeout(r, 0));
  assert_equals(navigation.entries().length, 1);

  let dispose_promise = new Promise(r => navigation.entries()[0].ondispose = r);

  // There is no spec for the maximum number of joint session history entries
  // (hence this is a .tentative.html test). However, all(?) browsers have a
  // settled on a maximum of 50.
  for (let i = 0; i < 50; i++)
    await navigation.navigate("#" + i).finished;
  await dispose_promise;
}, "Dispose should fire when an entry is removed from session history due to too many entries");
</script>