# File lib/sass/plugin/compiler.rb, line 201
    def update_stylesheets(individual_files = [])
      Sass::Plugin.checked_for_updates = true
      staleness_checker = StalenessChecker.new(engine_options)

      files = file_list(individual_files)
      run_updating_stylesheets(files)

      updated_stylesheets = []
      files.each do |file, css, sourcemap|
        # TODO: Does staleness_checker need to check the sourcemap file as well?
        if options[:always_update] || staleness_checker.stylesheet_needs_update?(css, file)
          # XXX For consistency, this should return the sourcemap too, but it would
          # XXX be an API change.
          updated_stylesheets << [file, css]
          update_stylesheet(file, css, sourcemap)
        else
          run_not_updating_stylesheet(file, css, sourcemap)
        end
      end
      run_updated_stylesheets(updated_stylesheets)
    end