1) The User Login Test
By default Drupal sets the user login page as /user, so the test is simply type in the websites url followed by /user. If the site goes to a login page you can confirm it by looking at the default format with Username and Password.

You can also get variants of "Create new account", "Log In", and "Request new password" tabs on the top of the page.

2) jQuery and Drupal JS includes test
Go to any page of the website and view page source.