Ruby on Rails : how to test a controller?

Question

I'm learning Ruby. I'm now trying to test one of my controller.

My test file is myapp/test/testing.rb while my controller is located at myapp/app/controllers/test_controller.rb.

The content of testing.rb is

data = testController.mymethod()
puts(data)

But when doing

ruby myapp/test/testing.rb

in the terminal, I get a warning :

Traceback (most recent call last):myapp/test/testing.rb:6:in `': uninitialized constant testController (NameError)

Could someone explain me what i'm doing is wrong and how I should do this ?

Thanks !

Answer 1

The currently accepted way to test rails controllers is by sending http requests to your application and writing assertions about the response.

Rails has ActionDispatch::IntegrationTest which provides integration tests for Minitest which is the Ruby standard library testing framework. Using the older approach of mocking out the whole framework with ActionDispatch::ControllerTest is no longer recommended for new applications.

This is your basic "Hello World" example of controller testing:

require 'test_helper'
 
class BlogFlowTest < ActionDispatch::IntegrationTest
  test "can see the welcome page" do
    get "/"
    assert_select "h1", "Welcome#index"
  end
end

Controllers can also be tested at a higher level through system tests which emulatate the user interacting with the application.

You can also use RSpec which is different test framework with a large following. In RSpec you write request specs which are just a thin wrapper on top of ActionDispatch::IntegrationTest.