#Rspec in Rails

Part I: Setup

Objectives
install rspec in rails app
create unit tests for our model validations
create controller specs to test blog routes

Terms

• System Under Test: some application component being tested or "what's being tested."
• Dependent-On Component: some application component connected to the SUT, but not really the subject of the test.
• Four Phase Test: is a methodology of setting up tests that breaks down a test into four phases: setup, exercise, verify, and teardown.

Rspec - Rails Installation

---

Clone this application

(It's always best to refer to offical documentation, see Resource#1, in case these instructions go out of date eventually.)

Step 1:

Add rspec rails to your Gemfile in the development, test group and bundle install

Gemfile

    group :development, :test do
      gem 'rspec-rails', '~> 3.0.0'
    end

Terminal
bundle install

Step 2:

Create spec directory, and necessary configurations

Terminal
rails generate rspec:install

and go to the .rspec file and remove the line that says

--warnings

This adds spec/spec_helper.rb and .rspec files that are used for configuration. See those files for more information.

Step 3:

Create a spec file for our model.
This is only necessary if you had a model created before you installed rspec.

Terminal
rails generate rspec:model article

Step 4:

Run your rspec tests (they should all pass as you don't have any)

Terminal
rspec or bundle exec rspec

To run specific specs

	# Run only model specs
	rspec spec/models
	
	# Run only specs for ArticlesController
	rspec spec/controllers/articles_controller_spec.rb

Rspec Rails Part II

Objectives
Identify the RSpsec directory structure and the purpose of each folder
Identify the purpose and give examples of Controller Specs and related structures stubs
Employ stubs to solve common testing problems

RSpec Directory

Typical Spec Folders

• Model
• Controller

Model Specs

The point of a model spec is to test data validations and expected model behaviors.

Setup FFaker

It would be better if your Factories didn't always create the same kind of objects and had more interesting our more realistic test data.

Thus we use a gem called FFaker to give us better test data.

Setup Gemfile

  group :development, :test do
	...
    gem 'ffaker'
  end

Controller Specs

In a controller we might have not yet implemented the model details we would expect to be testing our application, but we still need to write valid tests that describe the behavior of our controller. The helps others focus on reading our specs to work toward implementing the controller.

Stub

A stub is a method on an object that we wish to have some control over for testing purposes and whose true functionality is of little value to the test being written.

Stubbing In Our Rails Application

The most common thing to go stubbing is the current_user, which is something we will not care to test directly. Nevertheless you will still test the current_user method in a helper test for example. require 'rails_helper'

require 'rails_helper'

RSpec.describe ArticlesController, :type => :controller do
  before do
    user_params = Hash.new
    user_params[:email] = Faker::Internet.email
    user_params[:email_confirmation] = user_params[:email]
    user_params[:password]  = "blah"
    user_params[:password_confirmation] = user_params[:password]
    @current_user = User.create(user_params)
    allow_any_instance_of(ApplicationController).to receive(:current_user).and_return(@current_user)
  end

  describe "Get #index" do
    it "should render the :index view" do 
      get :index
      expect(response).to render_template(:index)
    end

    it "should assign @articles" do
     all_articles = Article.all
     get :index
     expect(assigns(:articles)).to eq(all_articles)
    end
  end
  
  describe "Get #new" do
    it "should assign @article" do
      get :new
      expect(assigns(:article)).to be_instance_of(Article)
    end

    it "should render the :new view" do
      get :new
      expect(response).to render_template(:new)
    end 
  end
  
  describe "Post #create" do
    it "should redirect_to 'article_path' after successful create" do
      post :create, article: {title: "blah", content: "blah"}
      expect(response.status).to be(302)
      expect(response.location).to match(/\/articles\/\d+/)
    end

    it "should add article to current_user" do
      count = @current_user.articles.all.count
      post :create, article: {title: "blah", content: "blah"}
      expect(@current_user.articles.count).to be > count
    end

    it "should redirect when create fails" do
      # a stub on the create method
      allow(@current_user.articles).to receive(:create).and_return(false)
      post :create, article: { title: "blah", content: "blah"}
      expect(response).to redirect_to(new_article_path)
    end
  end
end

Stub Resources

• Rspec Stubs: https://www.relishapp.com/rspec/rspec-mocks/v/2-3/docs/method-stubs

• Rspec Stubs Examples: http://old.rspec.info/documentation/mocks/stubs.html

Resources

---

1. Rspec-Rails Documentation https://github.com/rspec/rspec-rails
2. Model Specs https://www.relishapp.com/rspec/rspec-rails/docs/model-specs
3. Request Specs https://www.relishapp.com/rspec/rspec-rails/docs/request-specs/request-spec
4. Matchers https://www.relishapp.com/rspec/rspec-expectations/docs/built-in-matchers
5. Matchers https://www.relishapp.com/rspec/rspec-expectations/v/3-1/docs/built-in-matchers
6. Model Specs Example https://github.com/wdi-sf-july/validation_tests
7. Controller Specs https://www.relishapp.com/rspec/rspec-rails/docs/controller-specs