accumulate_descendants

# File activesupport/lib/active_support/descendants_tracker.rb, line 39
      def accumulate_descendants(klass, acc)
        if direct_descendants = @@direct_descendants[klass]
          acc.concat(direct_descendants)
          direct_descendants.each { |direct_descendant| accumulate_descendants(direct_descendant, acc) }
        end
      end