スペルに気をつけろ
ititialise と書いてエラーがでてえらい手間くった
class Cart attr_reader :items attr_reader :total_price def initialize @items = [] @total_price = 0.0 end def empty! @items = [] @total_price = 0.0 end def add_product(product) item =@items.find {|i| i.product_id == product.id} if item item.quantity += 1 else item = LineItem.for_product(product) @items << item end @total_price += product.price end end