Over the line

GSoC-2014 isitfedoraruby - Week 3

~3 min read in opensource

Testing, testing, testing. Diving into BDD for the first time can be a little tedious but you sure learn a lot. In the ruby/rails world there is a ton of excellent tools to help you test your app. Some more popular than the others. I'm no exception so I picked what the majority of the community dictated.

Testing tools

Rspec

The Rspec test suite is well established among ruby developers and has a big community to support it. You can also find many good books about it. One that I highly recommend is Everyday Rails Testing with RSpec. It basically includes all the tools I'll be using, I'm a little biased I admit it but it is really worth it.

Here are the specs that will be populated with tests over time.

models
├── bug_spec.rb
├── build_spec.rb
├── dependency_spec.rb
├── fedora_rpm_spec.rb
├── rpm_version_spec.rb
└── ruby_gem_spec.rb

Currently, I have worked only on bug_spec.rb which is finished for the time being.

# app/spec/models/bug_spec.rb
#
# == Schema Information
#
# Table name: bugs
#
#  id            :integer          not null, primary key
#  name          :string(255)
#  bz_id         :string(255)
#  fedora_rpm_id :integer
#  is_review     :boolean
#  created_at    :datetime
#  updated_at    :datetime
#  last_updated  :string(255)
#  is_open       :boolean
#
require 'rails_helper'

describe Bug do
  it 'has valid factory' do
    expect(create(:bug)).to be_valid
  end

  before(:all) do
    @bug = create(:bug)
    @bugzilla_url = 'https://bugzilla.redhat.com/show_bug.cgi?id='
  end

  it 'has valid bugzilla url' do
    expect(@bug.url).to match(/#{Regexp.quote(@bugzilla_url)}\d+/)
  end

  it 'is a Review Request' do
    expect(@bug.is_review).to eq true
  end

  it 'is open' do
    expect(@bug.is_open).to eq true
  end

  it 'is closed' do
    @bug.is_open = false
    expect(@bug.is_open).to eq false
  end

end

Here I'm using the new rspec method expect(object).to instead of the old one object.should.

In the validation of the bugzilla url I wanted to test against a regular expression that would return the bug url and bug number. At first I used /#{@bugzilla_url}\d+/ but that was interpreted into /https:\/\/bugzilla.redhat.com\/show_bug.cgi?id=\d+/. So, the slashes where treated as regexp wildcards. The trick I learned is to enclose the string into Regexp.quote(str). This method escapes any characters that would otherwise have special meaning1.

FactoryGirl

FactoryGirl is a replacement for fixtures, Rails' default way of creating test data. In my first attempt I used it to create a Bug object.

# app/spec/factories/bugs.rb

FactoryGirl.define do
  factory :bug do |b|
    b.bz_id '12345'
    b.is_review true
    b.is_open true
  end 
end

So, when I call create(:bug) in my bug_spec.rb it automatically creates a new Bug object in the database with the predefined attributes I gave it in the factory file. I could probably use build(:bug) instead of create and that would simply create the object but not save it in the database. This could get a lot better since it takes 2.2 seconds to just run 5 tests. Refactoring will come later, I'll primarily focus on making enough tests to cover as many edge cases as I can find.

Cucumber/capybara

So far I talked about unit testing. When it comes to integration testing, that is how the application as a whole behaves, there is cucumber and capybara. I haven't actually used any of these two yet. Cucumber is known for its descriptive language and better used when one works with a non-programmer product owner that doesn't want to look at a lot of code2. I'll probably just go with capybara.

Setting a Rails development environment

I spent quite a lot of time to find the proper gems and configuration to have a nice setup. This will do for an article of its own so I won't go into details.

TODOs

Except for preparing the test suite, I'm also into cleaning the code where possible and necessary. There are some functions that need removing, but I have to do it carefully, don't want to break anything and without tests I cannot be 100% sure. So far I have used the rubocop gem with some interesting findings (exactly 666 warnings/errors). I will talk about it next week. Now go and watch the Number of the beast.


  1. http://ruby-doc.org/core-2.1.2/Regexp.html#method-c-quote 

  2. Quote taken from Everyday Rails Testing with RSpec 

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