Controller tests in Ruby on Rails - Cheat Sheet & Quick Revision

Recall & Review

beginner

What is the main purpose of controller tests in Rails?

Controller tests check if the controller actions respond correctly to requests, render the right views, and handle data properly.

beginner

Which HTTP methods are commonly tested in Rails controller tests?

GET, POST, PATCH/PUT, and DELETE are the common HTTP methods tested to simulate user actions on resources.

beginner

In Rails controller tests, what does the 'get :index' command do?

It simulates a GET request to the 'index' action of the controller, allowing you to test the response and assigned variables.

intermediate

How do you check if a controller action redirects to another page in Rails tests?

Use 'assert_redirected_to' with the expected path to verify the controller action sends a redirect response.

intermediate

Why is it important to test both successful and unsuccessful controller actions?

Testing both ensures your app handles normal cases and errors gracefully, improving reliability and user experience.

Which method simulates a POST request in Rails controller tests?

A patch

B get

C delete

D post

The 'post' method simulates sending a POST request to a controller action.

What does 'assert_response :success' check in a controller test?

A The action returns a 200 OK status

B The action redirects to another page

C The action raises an error

D The action renders a JSON response

'assert_response :success' verifies the HTTP status code is 200, meaning the request was successful.

How do you test that a controller action assigns a variable in Rails tests?

A assert_redirected_to

B assert_template

C assigns(:variable_name)

D assert_equal

'assigns(:variable_name)' lets you check the value assigned to an instance variable in the controller.

Which Rails testing framework is commonly used for controller tests?

A JUnit

B RSpec

C Mocha

D Jest

RSpec is a popular Ruby testing framework often used for Rails controller tests.

What is the purpose of 'assert_template' in controller tests?

A Verify the rendered view template

B Check the HTTP status code

C Test database changes

D Simulate a user login

'assert_template' confirms that the controller rendered the expected view template.

Explain how to write a basic controller test for the 'show' action in Rails.

Think about the steps to simulate a request and check the results.

Describe why testing both success and failure cases in controller actions is important.

Consider what happens when things go right and when they go wrong.