getting started with Cucumber and Webrat on Rails

A couple of months ago I started using Cucumber in one of my projects. I think it’s a great tool for large projects. It makes it easier for developers joining the project and it gives the development team a lot of confidence when changing the code.

If you have a running set of tests, you know that you can go in, write a failing test, modify the code, add a feature and then run the tests again. If the tests fail, you broke something that was working: fix it. If you didn’t, great news: you have a new working feature!

There is a great Railscasts that explains how to get started: http://railscasts.com/episodes/155-beginning-with-cucumber

Here is a set of steps to follow.

1. Create your Rails app

rails blog

2. Add Cucumber and Webrat to your environment.rb

config.gem 'cucumber',    :lib => false,
  :version => '=0.4.3'
config.gem 'webrat',      :lib => false,
  :version => '>=0.5.3'
config.gem 'cucumber-rails',      :lib => false,
  :version => '>= 0.3.1'

3. Install your gems

cd blog
sudo rake gems:install

4. Generate your Cucumber code

cd blog
./script/generate cucumber --webrat

3. Start writing feature files

For example:

vi features/list_posts.feature

Feature: Listing all the posts in the blog
  As a user
  I want to see all the posts in the blog

  Scenario: I go to the posts list page and I see all the posts
    Given there is a post titled "Awesome post" with content "My cool content"
    When I go to the posts page
    Then I should see what is up
    And I should see "Awesome post"
    And I should see "My cool content"
    And I should not see "New post"

Then /^I should see what is up$/ do
  save_and_open_page
end

Given /^there is a post titled "([^\"]*)" with content "([^\"]*)"$/ do |title, content|
  Post.new(:title => title, :content => content).save
end