You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: command.rb
    path of file: ./repos/artichoke/artichoke-backend/vendor/ruby/lib/rubygems
    
    the code of the file until where you have to start completion: # frozen_string_literal: true
#--
# Copyright 2006 by Chad Fowler, Rich Kilmer, Jim Weirich and others.
# All rights reserved.
# See LICENSE.txt for permissions.
#++

require_relative 'optparse'
require_relative 'requirement'
require_relative 'user_interaction'

##
# Base class for all Gem commands.  When creating a new gem command, define
# #initia
    
  def add_extra_args(args)
    result = []

    s_extra = Gem::Command.specific_extra_args(@command)
    extra = Gem::Command.extra_args + s_extra

    until extra.empty? do
      ex = []
      ex << extra.shift
      ex << extra.shift if extra.first.to_s =~ /^[^-]/ # rubocop:disable Performance/StartWith
      result << ex if handles?(ex)
    end

    result.flatten!
    result.concat(args)
    result
  end