class ActiveRecord::Associations::HasManyAssociation

def delete_records(records, method)
  if method == :destroy
    records.each(&:destroy!)
    update_counter(-records.length) unless reflection.inverse_updates_counter_cache?
  else
    query_constraints = reflection.klass.composite_query_constraints_list
    values = records.map { |r| query_constraints.map { |col| r._read_attribute(col) } }
    scope = self.scope.where(query_constraints => values)
    update_counter(-delete_count(method, scope))
  end
end