nested_records_changed_for_autosave?

# File activerecord/lib/active_record/autosave_association.rb, line 243
    def nested_records_changed_for_autosave?
      self.class.reflect_on_all_autosave_associations.each do |reflection|
        if association = association_instance_get(reflection.name)
          if [:belongs_to, :has_one].include?(reflection.macro)
            return true if association.target && association.target.changed_for_autosave?
          else
            association.target.each {|record| return true if record.changed_for_autosave? }
          end
        end
      end
      false
    end