Rails post deploy asset compiling

gistfile1.rb

# Checks to see if the release you're deploying and the last version's "assets" directories have
  #   the same lines (content). If they do, don't run the asset precompilation.
  #
  # Notes on this at the delicious stackoverflow.com: 
  #  http://stackoverflow.com/questions/9016002/speed-up-assetsprecompile-with-rails-3-1-3-2-capistrano-deployment
  #
  # @note This fucks things up when you add stuff to the precompile list. It won't precompile 
  #   those new items 'cause it doesn't think there is anything new. A little bit manual but is a
  #   gotcha so would be nice to handle with this as well.
  #
  namespace :assets do
    task :precompile, :roles => :web, :except => { :no_release => true } do
      from = source.next_revision(current_revision)
      if capture("cd #{latest_release} && #{source.local.log(from)} vendor/assets/ app/assets/ | wc -l").to_i > 0
        run %{rm -rf #{latest_release}/public/assets/*}
        run %Q{cd #{latest_release} && #{rake} RAILS_ENV=#{rails_env} #{asset_env} assets:precompile}
      else
        logger.info "Skipping asset pre-compilation because there were no asset changes"
      end
    end
  end