method_missing

# File actionmailer/lib/action_mailer/parameterized.rb, line 117
        def method_missing(method_name, ...)
          if @mailer.action_methods.include?(method_name.name)
            ActionMailer::Parameterized::MessageDelivery.new(@mailer, method_name, @params, ...)
          else
            super
          end
        end