add_destroy_callbacks

# File activerecord/lib/active_record/associations/builder/association.rb, line 144
    def self.add_destroy_callbacks(model, reflection)
      if reflection.deprecated?
        # If :dependent is set, destroying the record has a side effect that
        # would no longer happen if the association is removed.
        model.before_destroy do
          report_deprecated_association(reflection, context: ":dependent has a side effect here")
        end
      end

      model.before_destroy(->(o) { o.association(reflection.name).handle_dependency })
    end