upgrade sass-rails gem to 5.0 gives deprecation warning

Question

We upgraded to sass-rails version 5.0.0 and are getting this deprecation warning:

DEPRECATION WARNING: Extra .css in SCSS file is unnecessary. Rename /Users/foo/         


        

Answer 1

Yes you need to rename your .css.scss to just .scss, as .css.scss will not be supported in sprockets 4.

If you want to suppress the deprecation temporary you can the following to config/initializer/deprecations.rb

Rails.application.config.after_initialize do
  old_behaviour = ActiveSupport::Deprecation.behavior
  ActiveSupport::Deprecation.behavior = ->(message, callstack) {
    unless message.starts_with?('DEPRECATION WARNING: Extra .css in SCSS file is unnecessary.',
                                'DEPRECATION WARNING: Extra .css in SASS file is unnecessary.')
      old_behaviour.each { |behavior| behavior[message,callstack] }
    end
  }
end

Or you can monkey patch to not to generate the message like this:

module DisableCssDeprecation
  def deprecate_extra_css_extension(engine)
    if engine && filename = engine.options[:filename]
      if filename.end_with?('.css.scss','.css.sass')
        engine
      else
        super
      end 
    end
  end
end

module Sass ; module Rails ; class SassImporter
  prepend DisableCssDeprecation
end ; end ; end