Migrating a script that limited how many units were discounted

危险配对 D5。这个文件和它的搭档看起来几乎一样，行为却不同，在判断您手上是哪一个之前，请把两份都读一遍。

# GENERATED BY THE SHOPIFY SCRIPT CREATOR APP

class ConditionalDiscount < Campaign
  def initialize(condition, customer_qualifier, cart_qualifier, line_item_selector, discount, max_discounts)
    super(condition, customer_qualifier, cart_qualifier, line_item_selector)
    @discount = discount
    @items_to_discount = max_discounts == 0 ? nil : max_discounts
  end

  def run(cart)
    return unless qualifies?(cart)
    applicable_items = cart.line_items.select { |item| @line_item_selector.nil? || @line_item_selector.match?(item) }
    applicable_items.each do |item|
      break if @items_to_discount == 0
      if !@items_to_discount.nil? && (item.quantity > @items_to_discount)
        new_item = item.split({ take: @items_to_discount })
        @discount.apply(new_item)
        position = cart.line_items.find_index(item)
        cart.line_items.insert(position + 1, new_item)
        @items_to_discount = 0
      else
        @discount.apply(item)
        @items_to_discount -= item.quantity unless @items_to_discount.nil?
      end
    end
  end
end

CAMPAIGNS = [
  ConditionalDiscount.new(
    :all, nil, nil,
    ProductTypeSelector.new(:does, ["Sale"]),
    PercentageDiscount.new(30, "30% off first 2"),
    2
  ),
].freeze

CAMPAIGNS.each do |campaign|
  campaign.run(Input.cart)
end

Output.cart = Input.cart

识别为 Discount on the first few units，重建为 bxgy 类型的优惠。下面是优惠实际保存时使用的配置键，您可以逐项核对自己的重建结果。

基于我们的公开演示店铺 Meridian Goods 搭建，因此这里的每个价格都可以复现，而不必凭信任接受。下方的折扣金额，是结账时运行的同一个引擎针对这个购物车算出的结果。

危险配对 D6。这个文件和它的搭档看起来几乎一样，行为却不同，在判断您手上是哪一个之前，请把两份都读一遍。

DISCOUNT_PERCENTAGE = 30
MAX_UNITS = 2

num_to_discount = MAX_UNITS

Input.cart.line_items.each_with_index do |line_item, position|
  break if num_to_discount <= 0
  next unless line_item.variant.product.tags.include?("limited")

  if line_item.quantity > num_to_discount
    split_line_item = line_item.split(take: num_to_discount)
    Input.cart.line_items.insert(position + 1, split_line_item)
    line_item = split_line_item
  end

  line_item.change_line_price(
    line_item.line_price * (1.0 - (DISCOUNT_PERCENTAGE / 100.0)),
    message: "30% off your first 2"
  )
  num_to_discount -= line_item.quantity
end

Output.cart = Input.cart

识别为 Discount on the first few units，重建为 bxgy 类型的优惠。下面是优惠实际保存时使用的配置键，您可以逐项核对自己的重建结果。

基于我们的公开演示店铺 Meridian Goods 搭建，因此这里的每个价格都可以复现，而不必凭信任接受。下方的折扣金额，是结账时运行的同一个引擎针对这个购物车算出的结果。