Rails 3.1 Assets

coffee_script.rb

# lib/action_view/template/handlers/coffee_script.rb

class ActionView::Template::Handlers::CoffeeScript
  def call template
    "CoffeeScript.compile #{template.source.inspect}"
  end
end

Gemfile

gem 'coffee-script'
gem 'compass',
  :git    => 'git://github.com/chriseppstein/compass.git',
  :branch => 'master'
gem 'rails_assets',
  :git    => 'git://github.com/wycats/rails_assets.git'

sass.rb

# lib/action_view/template/handlers/sass.rb

class ActionView::Template::Handlers::Sass
  def initialize options = {}
    @options = options
  end

  def call template
    <<CODE
compiler = Compass::Compiler.new *Compass.configuration.to_compiler_arguments
options  = compiler.options.merge(#{@options.inspect})
Rails.logger.info "#{template.inspect}"
Sass::Engine.new(#{template.source.inspect}, options).render
CODE
  end
end

template_handlers.rb

# config/initializers/template_handlers.rb

# Coffee.
require 'action_view/template/handlers/coffee_script'

ActionView::Template.register_template_handler :coffee,
  ActionView::Template::Handlers::CoffeeScript.new

# Sass.
require 'action_view/template/handlers/sass'

ActionView::Template.register_template_handler :sass,
  ActionView::Template::Handlers::Sass.new

ActionView::Template.register_template_handler :scss,
  ActionView::Template::Handlers::Sass.new(:syntax => :scss)

stylesheets_directory = Rails.root.join('app', 'assets', 'stylesheets').to_s
Compass::Frameworks.register 'rails_assets',
  :stylesheets_directory => stylesheets_directory,
  :templates_directory   => stylesheets_directory