Learn RSpec in 15 Minutes or Less

RSpec BDD Rails | comments

You can learn RSpec in less than 15 minutes especially if you are not Rails newbie. RSpec and BDD is a way of getting an application done right in an unbelievably short period of time.

BDD is behaviour-driven development. You think about all the specification and expectations regarding a project before working on it. That’s what most software developers normally do. I spend at least one day just thinking about specifications and based on experience - I think about several details like:

1. User Interface (Look and feel)
2. Project Goals (What makes the application fun? Who are your audience? How can you profit from the project?)
3. Plugins and Gems required by the project
4. Key Features - (What feature can’t be deferred?)
5. What can go wrong? (OOP is now pronounced “uh-oh P”)

Regarding number 3 and 4, they are quite related and it usually takes over a day to think about everything. For number 5, I usually don’t stress about it but I do consider things like server issues.

Let’s do another blog application :

#on config/environments/test.rb

config.gem 'rspec-rails', :lib=>false
config.gem 'rspec', :lib=>false
config.gem 'cucumber', :lib=>false

Do rake gems:install RAILS_ENV=test

script/generate rspec_scaffold Post user_id:integer title:string body:text

The code above generates everything - MVC + Spec tests. Someone asked me if I do use the default scaffolds in Rails. I do use scaffolding but with RSpec (rspecscaffold).

Adding Authlogic for authentication. (If required later, you can try declarative authorization or role requirement for role-based authorization.)

script/plugin install git://github.com/binarylogic/authlogic.git

Here’s a nice write-up on Rspec and authlogic.

A more real-world example of an rspec model test (taken off a previous project of mine) of RSpec:

#in spec/models/article_spec.rb 

require File.expand_path(File.dirname(__FILE__) + '/../spec_helper')

describe Article do
  before(:each) do
    @article = Article.new
    @filename = "01.jpg"
    @file_type = "image/jpeg"
    @file_size = "304986"
    @file_updated_at 	= Time.now
    @date = Time.now
  end

  it "should not be valid when empty" do
    @article.should_not be_valid
  end

  ['user_id, title, body, category_id, date'].each do |field|
    it "should require #{field}" do
     @article.should_not be_valid
    end
  end
  
  it "should be valid when details are not empty" do
    @article.user_id = 1
    @article.title = "A long day and things are still not right"
    @article.body = "There are many variations of passages of 
Lorem Ipsum available, but the majority have suffered 
alteration in some form, by injected humour, or randomised words 
which don't look even slightly believable. 
If you are going to use a passage of Lorem Ipsum, you need 
to be sure there isn't anything embarrassing hidden in the 
middle of text.

All the Lorem Ipsum generators on the Internet tend to 
repeat predefined chunks as necessary, making this the first 
true generator on the Internet. 
It uses a dictionary of over 200 Latin words, 
combined with a handful of model sentence structures, 
to generate Lorem Ipsum which looks reasonable. 
The generated Lorem Ipsum is therefore always free 
from repetition, injected humour, or non-characteristic 
words etc."
    @article.category_id = Category.new
    @article.photo_file_name = @filename
    @article.photo_content_type = @file_type
    @article.photo_file_size = @file_size
    @article.photo_updated_at = @file_updated_at
    @article.date = @date
    @article.should be_valid
  end


end

RSpec in Rails 3

Based on observation, RSpec has better acceptance in the rails community than the default test suite. I am expecting Rails 3 book to cover more about automated testing with RSpec.

Happy New Year! I love Rails and all the people working hard to make it better.