encrypted_attribute?

# File activerecord/lib/active_record/encryption/encryptable_record.rb, line 146
      def encrypted_attribute?(attribute_name)
        name = attribute_name.to_s
        name = self.class.attribute_aliases[name] || name

        return false unless self.class.encrypted_attributes&.include? name.to_sym

        type = type_for_attribute(name)
        type.encrypted? read_attribute_before_type_cast(name)
      end