def command_line(head_arguments='', tail_arguments='')
      args = [head_arguments, default_args, tail_arguments].flatten.compact.select { |s| s.length > 0 }.join ' '
      "#{executable} #{args}"
    end
def command_line(head_arguments='', tail_arguments='')
      args = [head_arguments, default_args, tail_arguments].flatten.compact.select { |s| s.length > 0 }.join ' '
      "#{executable} #{args}"
    end
Merges the given with the configured arguments and returns the command
 line to execute.

 @param  [String] head_arguments
         The arguments to pass to the executable before the default arguments.

 @param  [String] tail_arguments
         The arguments to pass to the executable after the default arguments.

 @return [String]
         The command line to execute.