Even with an army of QA Engineers, some bugs will sneak through. QA time on untested code takes longer, and debugging the code even longer than that. The release process can go from a day to several days, or even weeks.

With BDD, when new features are added to the application, it as easy as running your spec or test suite to ensure that the original functionality is undamaged. It of course seems like a no brainer to me now. It’s like looking back and remembering when you thought the world was flat, and seeing how narrow minded you were. The moral of the story? Test before you code! You fill find yourself with more time, and less headaches.

export PATH=$HOME/jruby/bin:$PATH

Next install the Celerity gem in jRuby (we are using the github version rather than the ruby forge version, as it provides a later version):

jruby -S gem install jarib-celerity --source=http://gems.github.com

Now install the Culerity gem. This provides the interface between Celerity and your environment without forcing you to run in jRuby

 gem install langalex-culerity --source http://gems.github.com

Place this in your test environment:

# config/environments/test.rb
 
config.gem "langalex-culerity", :lib => false

I call :lib => false here to avoid loading the gem. This is done in the file generated by culerity. Finally remove features/steps/webrat_steps.rb as it will conflict with Culerity, and run:

script/generate culerity

Enjoy! Culerity should have very similar syntax to webrat, however keep in mind you may see some differences that you may need to adjust.

Create the Rails Project
Go to your projects directory and create a rails project. Just for fun, let’s call it ‘bank’:

Create MySQL Databases
Go into mysql and create the two databases that rails has set up the bank project to use:

Put Gems Into Environments
Edit the files

and

and add the following lines:

config.gem "thoughtbot-factory_girl", :lib => 'factory_girl', :source => 'http://gems.github.com'
config.gem "rspec", :version => '1.2.2', :lib => 'spec'
config.gem "rspec-rails", :version => '1.2.2', :lib => false

This sets up the test and development environments to use rspec and factory girl.

Install the Gems
Install the gems referenced in your environments:

You’ll see output that says that the gems were installed, if you didn’t have them already.

Bootstrap RSpec
Do a:

You will see the following:

This generates some default rspec files and directories that the project will use.

Generate Model, Test, and Migration with rspec_model
Do a:

You will see the following output:

This will create a default test at

and a BankAccount model in

and a migration in

You can also do a script/generate rspec_scaffold BankAccount.

Edit the Test
Go to

and you will see:

require File.expand_path(File.dirname(__FILE__) + '/../spec_helper')
 
describe BankAccount do
  before(:each) do
    @valid_attributes = {
    }
  end
 
  it "should create a new instance given valid attributes" do
    BankAccount.create!(@valid_attributes)
  end
end

Since this is a bank account, one of the behaviors that we would expect is to be able to make deposits into it. That being the case, let’s change the test to

require File.expand_path(File.dirname(__FILE__) + '/../spec_helper')
 
describe BankAccount do
  before(:each) do
    @bank_account = BankAccount.create
    @bank_account.balance = 0
  end
 
  it "should increase the balance upon deposit" do
    @bank_account.deposit(100)
    @bank_account.balance.should == 100
  end
end

Also, edit

and change ‘progress’ to ’specdoc’ (because it will make rspec output look a lot better)

Edit the Migration
We need to add the ‘balance’ attribute to the model. Go to

(or some file like that)

and change the migration to

class CreateBankAccounts < ActiveRecord::Migration
  def self.up
    create_table :bank_accounts do |t|
      t.float :balance
 
      t.timestamps
    end
  end
 
  def self.down
    drop_table :bank_accounts
  end
end

Edit the Model Now we need to add the deposit method to the BankAccount model. Go to

Change the class to

class BankAccount < ActiveRecord::Base
 
  def deposit(amount)
    self.balance = self.balance + amount
  end
 
end

Migrate the DB, Run RSpec Now, do a

and then a

You should see:

At this point, RSpec is functioning.

Add Factory Girl
Want to add Factory Girl? The environments are already set up and gem is installed. The rest is not hard:

Create a ‘factories’ directory under the ’spec’ directory.

and make the file

and put this inside:

Factory.define :bank_account do |ba|
  ba.add_attribute :balance, 0
end

Edit the Test
Open

Change the body of the before each block to

@bank_account = Factory(:bank_account, :balance => 0)

Since the factory you just made (spec/factories/bank_accounts.rb) automatically sets the balance to 0, you could leave the body with just

@bank_account = Factory(:bank_account)

and it would still work.

The finished spec/models/bank_account_spec.rb will look like this:

require File.expand_path(File.dirname(__FILE__) + '/../spec_helper')
 
describe BankAccount do
  before(:each) do
    @bank_account = Factory(:bank_account, :balance => 0)
  end
 
  it "should increase the balance upon deposit" do
    @bank_account.deposit(100)
    @bank_account.balance.should == 100
  end
end

Watch RSpec Run With Factory Girl
Watch the test run with Factory Girl: