class Sass::Exec::SassConvert

def process_file(input, output)
  input_path, output_path = path_for(input), path_for(output)
  if input_path
    @options[:from] ||=
      case input_path
      when /\.scss$/; :scss
      when /\.sass$/; :sass
      when /\.less$/; raise "sass-convert no longer supports LessCSS."
      when /\.css$/; :css
      end
  elsif @options[:in_place]
    raise "Error: the --in-place option requires a filename."
  end
  if output_path
    @options[:to] ||=
      case output_path
      when /\.scss$/; :scss
      when /\.sass$/; :sass
      end
  end
  @options[:from] ||= :css
  @options[:to] ||= :sass
  @options[:for_engine][:syntax] = @options[:from]
  out =
    Sass::Util.silence_sass_warnings do
      if @options[:from] == :css
        require 'sass/css'
        Sass::CSS.new(read(input), @options[:for_tree]).render(@options[:to])
      else
        if input_path
          Sass::Engine.for_file(input_path, @options[:for_engine])
        else
          Sass::Engine.new(read(input), @options[:for_engine])
        end.to_tree.send("to_#{@options[:to]}", @options[:for_tree])
      end
    end
  output = input_path if @options[:in_place]
  write_output(out, output)
rescue Sass::SyntaxError => e
  raise e if @options[:trace]
  file = " of #{e.sass_filename}" if e.sass_filename
  raise "Error on line #{e.sass_line}#{file}: #{e.message}\n  Use --trace for backtrace"
rescue LoadError => err
  handle_load_error(err)
end