def get_input_files(args = {})
      command  = args.fetch(:command, nil)
      if command.nil?
        CodeLister.files(args)
      else
        # Note: base_dir must be the the same the directory where the command is executed from
        CodeLister.files_from_shell(command, args.fetch(:base_dir, "."))
      end
    end
def get_input_files(args = {})
      command  = args.fetch(:command, nil)
      if command.nil?
        CodeLister.files(args)
      else
        # Note: base_dir must be the the same the directory where the command is executed from
        CodeLister.files_from_shell(command, args.fetch(:base_dir, "."))
      end
    end
Get the list of input file

 @param [Hash<Symbol, Object>] args the input options
 @option args [String] :command the shell command to be used to get list of files
 @return [Array<String>] list of files in the format
         ["./Gemfile", "./lib/vim_printer/cli.rb", ..]