class_of_active_record_descendant

# File activerecord/lib/active_record/inheritance.rb, line 86
      def class_of_active_record_descendant(klass)
        if klass == Base || klass.superclass == Base || klass.superclass.abstract_class?
          klass
        elsif klass.superclass.nil?
          raise ActiveRecordError, "#{name} doesn't belong in a hierarchy descending from ActiveRecord"
        else
          class_of_active_record_descendant(klass.superclass)
        end
      end