Fast RSpec with a tiered environment: SPEC=(unit|model|full) rspec …

spec_helper.rb

mode = ENV["SPEC"] || "full"
require_relative "spec_helper_#{mode}"

spec_helper_full.rb

# This file is copied to spec/ when you run 'rails generate rspec:install'
ENV["RAILS_ENV"] ||= 'test'
require File.expand_path("../../config/environment", __FILE__)
require 'rspec/rails'

# Requires supporting ruby files with custom matchers and macros, etc,
# in spec/support/ and its subdirectories.
Dir[Rails.root.join("spec/support/**/*.rb")].each {|f| require f}

spec_helper_model.rb

require_relative "spec_helper_unit"

ENV["RAILS_ENV"] ||= "test"

# ActiveRecord
require "yaml"
require "active_record"
ActiveRecord::Base.establish_connection(
  YAML.load(File.read(RAILS_ROOT + "config/database.yml"))["test"]
)

# factory_girl
require_relative "factories"
require_relative "support/factory_girl"

# DatabaseCleaner
require "database_cleaner"
RSpec.configure do |config|
  config.before(:suite) do
    DatabaseCleaner.strategy = :transaction
    DatabaseCleaner.clean_with(:truncation)
  end
  config.before(:each) do
    DatabaseCleaner.start
  end
  config.after(:each) do
    DatabaseCleaner.clean
  end
end

# Enter database configurations into ActiveRecord
ActiveRecord::Base.send(:configurations=, YAML::load(ERB.new(IO.read(RAILS_ROOT + "config/database.yml")).result))

# We hates Devise :(
class ActiveRecord::Base
  def self.devise *parameters; end; def self.define_index *parameters; end#; def configurations; configs; end
end
module Devise; module Models; module Recoverable; end end end
class User < ActiveRecord::Base; attr_writer :password; def self.has_own_preferences *parameters; end end
require_relative "../app/models/user"

spec_helper_unit.rb

require "pathname"
RAILS_ROOT = Pathname.new(File.expand_path("../..", __FILE__))

# ActiveSupport
require "active_support"
require "active_support/dependencies"
%w{ extensions forms helpers mailers models presenters scripts }.each do |dir|
  ActiveSupport::Dependencies.autoload_paths <<
    File.expand_path("../../app/#{dir}", __FILE__)
end