title: How to e2e test an Angular app with Firebase authentication and Firestore using cypress
body: <p>I have an Angular app that uses Firebase Authentication for logging in and then reading and writing data to a Firestore database. I want to do some e2e tests for it.</p>
  
  <p>I would rather write the tests with mocked data or a local server. </p>
  
  <p>I haven't found any local way of running Firestore so far.
  I saw that you can stub out methods with cy.stub, but it's unclear to me how to do that with Angular2. How do I get a hold of the object that I want to stub out methods in? In the real code they are dependency injected in the constructor</p>
  
  <p>Or what is the preferred way of writing Cypress e2e test with Angular and Firebase (AngularFire2)? Any good recommendations?</p>
  
  <p>Thanks</p>