Adding Unit Test to Rails App

Tests were not a huge part of my learning when I was going through the Flatiron bootcamp. We focused much more on BDD or behavior driven development.

However, in the real world it seems that tests are much more of a mainstay. I recently began adding tests to one of my projects, a blog application. This blog will detail the very basic steps I took to start running model tests in my Ruby on Rails application.

First, in your Rails directory, go into the folder called test.

Within that directory find a folder called models.

Create a file in that folder named modelname_test.rb.

In this file, what I did was first require the rails test helper at the top of the page, then define my CategoryTest class inheriting from ActiveSupport::TestCase.

require 'test_helper'
class CategoryTest < ActiveSupport::TestCase
end

Within this class you can define your tests.

One thing that will make your life easier is to define a testable model instance variable at the beginning of the class so you can refer to it for all of your tests.

require 'test_helper'
class CategoryTest < ActiveSupport::TestCase
def setup
@category = Category.new(name: "Politics")
end
end

After this you can start writing your tests.

Here’s an example test :

require 'test_helper'
class CategoryTest < ActiveSupport::TestCase
def setup
@category = Category.new(name: "Politics")
end
test "category should be valid" do
assert @category.valid?
end
end

By running Rails test in your terminal, this will run tests to validate that the @category instance variable would be valid to save to the database (determined by the validations you set within your Category model).