RSpec 2 library for specifying and testing generators

RSpec 2 matchers, helpers and various utilities to assist in writing generator specs especially Rails 3 generators.

This project was extracted from my experiments with creating generators for jnunemaker's Canable, see My fork of Canable.

I attempted to test the generators I built but I noticed, that the only option I could find, was to use a special Rails TestCase class created for Test-Unit. So I thought I could wrap it to be used with RSpec 2; my BDD testing framework of choice!

Install

gem install rspec_for_generators

To install using edge

rake install

Usage

The following demonstrates an example usage. There are many more options and cool DSL convenience methods. Check out the code!

spec/spec_helper.rb

require 'rspec'

# The following somewhat ugly 'hack' is currently required for rails_spec_helper.rb to work.
# It's the relative root for which the Rails mock app is created. 
# So if it's set to point to the spec folder, then the temporary rails application 
# will be generated in ../tmp, relative to the folder of this file : File.dirname(__FILE__)
# Thus in this example the /tmp folder will be in the current project root. 

# Note: In the near future I will provide a better way to achieve this, by hooking into the Rails 3 loading 
# behavior as described in a *Rails Dispatch* article by *wycatz* 

module Rails
  def config_root_dir
    File.dirname(__FILE__)
  end
end    

# load this rspec toolbox to help spec generators
require 'rspec_for_generators'

spec/generators/canable.rb

Convenience way to define which generators to require

require_generators :canable => ['model', 'user']

spec/generators/model_generator_spec.rb

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

# list of generators to spec are loaded
require 'generators/canable'

describe 'model_generator' do
  # include Rails model helpers for AciveRecord
  # also available are: MongoMapper, Mongoid and DataMapper    
  # mongo_mapper, :data_mapper, :mongoid
  
  model_helper_for :active_record
  
  before :each do              
    # define generator to test
    RSpec::Generator.setup_generator 'model_generator' do
      tests Canable::Generators::ModelGenerator
    end    
    # ensure clean state before run
    remove_model 'account'    
  end

  after :each do              
    # ensure clean state after run  
    remove_model 'account'    
  end
    
  it "should not work without an existing Account model file" do            
    RSpec::Generator.with_generator do |g|   
      name = 'account'
      g.run_generator %w{account}
      g.should_not generate_file name, :model
    end
  end

  it "should decorate an existing Account model file with 'include Canable:Ables'" do            
    RSpec::Generator.with_generator do |g|  
      name = 'account'
      create_model name     
      g.run_generator %w{account}
      g.should generate_file name, :model do |content|
        content.should have_class name.camelize do |klass|
          klass.should include_module 'Canable::Ables'
        end
      end
    end
  end
end

Note on Patches/Pull Requests

Fork the project.
Make your feature addition or bug fix.
Add tests for it. This is important so I don't break it in a future version unintentionally.
Commit, do not mess with rakefile, version, or history. (if you want to have your own version, that is fine but bump version in a commit by itself I can ignore when I pull)
Send me a pull request. Bonus points for topic branches.