method_missing

# File actionpack/lib/action_dispatch/testing/integration.rb, line 390
      def method_missing(sym, *args, &block)
        reset! unless integration_session
        if integration_session.respond_to?(sym)
          integration_session.__send__(sym, *args, &block).tap do
            copy_session_variables!
          end
        else
          super
        end
      end