module Sass::Plugin

def update_stylesheets

If it has, it updates the CSS file.
in {file:SASS_REFERENCE.md#css_location-option} `:css_location`}.
to see if it's been modified more recently than the corresponding CSS file
Checks each Sass file in {file:SASS_REFERENCE.md#template_location-option `:template_location`}

Updates out-of-date stylesheets. 
def update_stylesheets
  return if options[:never_update]
  @checked_for_updates = true
  template_locations.zip(css_locations).each do |template_location, css_location|
    Dir.glob(File.join(template_location, "**", "*.sass")).each do |file|
      # Get the relative path to the file with no extension
      name = file.sub(template_location + "/", "")[0...-5]
      if !forbid_update?(name) && (options[:always_update] || stylesheet_needs_update?(name, template_location, css_location))
        update_stylesheet(name, template_location, css_location)
      end
    end
  end
end