code: def add(path)
        str = "#{path} filter=rgc diff=rgc"
        if content.include?(str)
          abort "`#{str}\n` is already included in #{@location}."
        end
  
        File.open(@location, 'a') do |f|
          f.write("#{str}\n")
        end
      rescue Errno::ENOENT
        abort "File #{@location} does not exists."
      rescue Errno::EACCES
        abort "File #{@location} is not accessible for writing."
      end
docs: Add new path to the gitattributes file