assert_valid_value

# File activerecord/lib/active_record/coders/yaml_column.rb, line 34
      def assert_valid_value(obj, action))
        unless obj.nil? || obj.is_a?(object_class)
          raise SerializationTypeMismatch,
            "can't #{action} `#{@attr_name}`: was supposed to be a #{object_class}, but was a #{obj.class}. -- #{obj.inspect}"
        end
      end