# File lib/mongoid/safety.rb, line 55
      def merge_safety_options(options = {})
        options ||= {}
        return options if options[:safe]

        unless Threaded.safety_options.nil?
          safety = Threaded.safety_options
        else
          safety = Mongoid.persist_in_safe_mode
        end
        options.merge!({ :safe => safety })
      end