Question

我正在关注“使用rails进行敏捷Web开发”一书。我有个问题。这是new控制器中的order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

rake test显示失败：

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。两个模型（carts和line_items）并且彼此相关。为什么cart.line_items为空？

Answer 1

分配到购物车后，

save您的列表项。

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

只是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。

Answer 2

或只使用write_attribute或update_attribute

li.write_attribute :cart, cart

预期的响应是＆lt;：success＆gt;，但是＆lt; 302＆gt;

2 个答案: