association_valid?

# File activerecord/lib/active_record/autosave_association.rb, line 320
      def association_valid?(reflection, record)
        return true if record.destroyed? || (reflection.options[:autosave] && record.marked_for_destruction?)

        validation_context = self.validation_context unless [:create, :update].include?(self.validation_context)
        unless valid = record.valid?(validation_context)
          if reflection.options[:autosave]
            record.errors.each do |attribute, message|
              attribute = "#{reflection.name}.#{attribute}"
              errors[attribute] << message
              errors[attribute].uniq!
            end
          else
            errors.add(reflection.name)
          end
        end
        valid
      end