# File lib/httpauth/digest.rb, line 497
      def update_from_credentials!(options)
        # TODO: update @h after nonce invalidation
        [:digest, :username, :realm, :password].each do |k|
          @h[k] = options[k] if options.include? k
        end
        @h[:response_body] = options[:response_body]
        @h[:nextnonce] = Utils.create_nonce @h[:salt]
        @h[:rspauth] = Utils.calculate_digest(@h, nil, :response)
      end