# File lib/bugzilla/bug.rb, line 214
    def _fields(cmd, *args)
      requires_version(cmd, 3.6)
      params = {}

      if args[0].kind_of?(Array) then
        x = args[0].map {|x| x.kind_of?(Integer)}.uniq
        if x.length == 1 && x[0] then
          params['ids'] = args[0]
        else
          x = args[0].map {|x| x.kind_of?(String)}.uniq
          if x.length == 1 && x[0] then
            params['names'] = args[0]
          end
        end
      elsif args[0].kind_of?(Hash) then
        params = args[0]
      elsif args[0].kind_of?(Integer) then
        params['ids'] = [args[0]]
      elsif args[0].kind_of?(String) then
        params['names'] = [args[0]]
      elsif args[0].nil? then
      else
        raise ArgumentError, "Invalid parameters"
      end

      @iface.call(cmd, params)
    end