ruby on rails - How to write proper rspec test for controller -

i have controller called application controller next method want write test for:

  def require_admin     p current_user.role     return if current_user && current_user.role == 'admin'     flash[:error] = "you not admin"     redirect_to root_path   end 

how write proper test it, , kind of test should be?

you shouldn't test implementation. try testing 'how should controller action behave non-admin user', might this:

context 'user not admin'   before     user.role = 'not_admin'     :some_action   end    'is redirected root_path'             expect(response).to redirect_to('/')   end   ... end