Rake task for minifying javascripts using YUI Compressor

javascripts.rake

namespace :javascripts do
  desc 'minify the javascript files residing in app/javascripts to public/javascripts'
  task :minify do
    RakeFileUtils.verbose false do
      Dir["app/javascripts/*.js"].each do |filename|
        outfile = filename.sub(/^app/, 'public').sub(/\.js$/, '.min.js')
        puts "#{filename} -> #{outfile}"
        sh(
          'java',
          '-jar',
          'vendor/yuicompressor/yuicompressor-2.4.2.jar',
          filename,
          '-o',
          outfile
        )
      end
    end
  end
end