Ember 3.0 acceptance redirect test hangs forever

I have a simple acceptance test written in the modern RFC 268 format for Ember 3.0.

The test is for a page where, if the user is unauthenticated, the URL immediately redirects to /login.

...

module('Acceptance | index', function (hooks) {
  setupApplicationTest(hooks);

  test('visiting / logged out', async function(assert) {
    assert.expect(1);

    // Test hangs here forever.
    await visit('/');

    assert.equal(currentURL(), '/login');
  });
});

This test worked great using the older format with moduleForAcceptance.

Unfortunately, this test hangs forever in Ember 3.0. Am I missing something here? Is there a better way to test a redirect?

There are no errors in the console, and the addition of some console.log statements show that the await is where the test hangs.