1

我正在关注“使用 Rails 进行敏捷 Web 开发”一书。我有个问题。这是我new在order控制器中的方法： 

def new
  @cart = current_cart
  if @cart.line_items.empty?
    redirect_to store_url, notice: "Your cart is empty"
    return
  end

  @order = Order.new

  respond_to do |format|
    format.html # new.html.erb
    format.json { render json: @order }
  end
end

这是测试：

test "should get new" do
  cart = Cart.create
  session[:cart_id] = cart.id
  li = LineItem.create(product: products(:ruby))
  li.cart = cart

  get :new
  assert_response :success
end

显示rake test失败：

Expected response to be a <:success>, but was <302>

我用rails命令行检查了它，如下所示：

cart = Cart.create
=> #<Cart id: 24, created_at: "2012-07-09 08:39:36", updated_at: "2012-07-09 08:39:36">

products = Product.create(:title => "Lorem Ipsum", :description => "Lorem Ipsum Lorem Ipsum Lorem Ipsum Lorem", :price => 49.50, :image_url => "ruby.png")
=> #<Product id: nil, title: "Lorem Ipsum", description: "Lorem Ipsum Lorem Ipsum Lorem Ipsum Lorem", image_url: "ruby.png", price: #<BigDecimal:434f108,'0.495E2',18(45)>, created_at: nil, updated_at: nil>

li = LineItem.create(product: products)
=> #<LineItem id: 106, product_id: nil, cart_id: nil, created_at: "2012-07-09 08:41:29", updated_at: "2012-07-09 08:41:29", quantity: 1, price: nil, order_id: nil>

li.cart = cart
=> #<Cart id: 24, created_at: "2012-07-09 08:39:36", updated_at: "2012-07-09 08:39:36">

li.cart显示相应的cart，但cart.line_items为空。这两个模型（carts 和 line_items）彼此相关。为什么是cart.line_items空的？

4

2 回答 2

2

save将您的列表项分配给购物车后。

test "should get new" do
  cart = Cart.create
  session[:cart_id] = cart.id
  li = LineItem.create(product: products(:ruby))
  li.cart = cart

  li.save! // Do this and make sure it doesn't raise an exception.

  get :new
  assert_response :success
end

仅分配不会在数据库中注册更改，因此@cart.line_items将保持为空。因此，在您的控制器中，if 检查将重定向。302 代码用于重定向。

于 2012-07-09T09:37:37.183 回答
0

或者只使用 write_attribute 或 update_attribute

li.write_attribute :cart, cart
于 2013-12-22T09:17:17.043 回答