thoughtbot--factory_bot/lib/factory_girl/attribute.rb

class Factory

  class Attribute #:nodoc:

    attr_reader :name
    attr_writer :static_value, :lazy_block

    def initialize (name)
      @name = name
    end

    def value (proxy)
      if @lazy_block.nil?
        @static_value
      else
        @lazy_block.call(proxy)
      end
    end

  end

end