Add Tests for Controllers and Helpers

[ashishdommety]

For Helpers (Unit Tests)

Using Jest, test individual functions that are pure (a.k.a no side-effects)

For Controllers (Integration Tests)

Use Mocha and Chai to test all the controllers in the application.

Also, use Sinon for stubbing and mocking.

• [ ] Organization Controllers
• [ ] Tutor Controllers
• [ ] Student Controllers
• [ ] Quiz Controllers
• [ ] Question Controllers