Hey guys! How are you?

This article is a part of a series that will teach how to create a production ready rails application. Today we're gonna talk about testing with rspec.

Table of content

• What is Rspec
• Setting up environment
• Configuring Rspec
• Test it out

What is Rspec

Rspec is a ruby gem that allow us to test our applications, it provides the best way to do TDD while developing new features.

Setting up environment

We need to follow those instructions to get rspec working:

Install the gems

group :test do
  # Rspec
  gem "rspec-rails", "~> 5.1.2"

  # Fake data generator
  gem "faker", "~> 2.23.0"

  # Clean database before each test execution
  gem "database_cleaner-active_record", "~> 2.0.1"

  # Factories
  gem "factory_bot_rails", "~> 6.2.0"

  # Models specs
  gem "shoulda-matchers", "~> 5.1.0"
end

Download the dependencies

bundle install

Generate Rspec configuration files

rails generate rspec:install

Require rails helper

To properly run specs we need to require rails helper on top of each spec file, to prevent this we can create a file called .rspec in the root path of the application and put the following content there:

--require rails_helper

Configuring Rspec

Now that we have all the setup done we need to properly configure rspec, to do so we need to edit rails_helper and spec_helper. You'll find the full code snippet in a pull request in the end of the article, nut here's a quick explanation of some important points:

Rails Helper

This file stores all rspec general configuration and some dependencies configurations such as factory_bot and shoulda_matchers. Another important thing is that on the top of the file we have a guard clause that prevents rspec to run in a environemnt different thant test, you should never remove this safe guard

Spec Helper

This file is simpler, it contains only some inclusions and basic setup, rails_helper requires this file to improve it configuration

Test it out

Now that everything should be ok lets test it out. To do so we need to create a spec file and verify if it's passing.

Create a file under the spec folder called test_spec.rb and put the following content there:

RSpec.describe do
  describe "rspec setup" do
    it "returns true" do
      expect(true).to be(true)
    end
  end
end

Now all you need to do is run rspec using this command:

rspec

You should look something like this if everything is ok:

You can either specify somethings to this command such as the file and line it should execute, here's an example:

rspec spec/test_spec.rb
rspec spec/test_spec.rb:3

You can see all the code changed here