object_filter.rb

module ActiveInteraction
  class ObjectFilter < Filter
    register :object

    def cast(value)
      @klass ||= klass

      if matches?(value)
        value
      else
        raise InvalidClassError, value.class.name
      end
    end

    private

    def klass
      options[:class]
    end

    def matches?(value)
      return true unless @klass

      @klass === value || value.is_a?(@klass)
    end

  end
end