def template_content
      if File.file?(@template_file) && File.readable?(@template_file)
        return File.read(@template_file)
      end

      raise ArgumentError, _("'%{template}' is not a readable file") % { template: @template_file }
    end
def template_content
      if File.file?(@template_file) && File.readable?(@template_file)
        return File.read(@template_file)
      end

      raise ArgumentError, _("'%{template}' is not a readable file") % { template: @template_file }
    end
Reads the content of the template file into memory.

 @return [String] The content of the template file.

 @raise [ArgumentError] If the template file does not exist or can not be
 read.

 @api private