ArgumentError in StoreController#add_to_cart: wrong number of arguments (1 for 0)

I am really new to Ruby and Rails but as you probably see I am trying to get the shopping card working from the book. I am getting this error but I really don't know what to do. I have looked up several of topics that stated the same problem but as far as I am, nothing has helped me out yet. Is there something wrong with the Product model?

This is in the StoreController and I believe it is all good.

  def add_to_cart     @cart = find_cart     product = Product.find(params[:id])     @cart.add_product(product)   end

Thanks in advance

Well, let's see, the title of your post is "ArgumentError in StoreController#add_to_cart, wrong number of arguments (1 for 0)." I assume that this is because that's the error you are seeing.

So what could that mean? It means that someone is calling StoreController#add_to_cart with an argument, but add_to_cart doesn't accept any arguments.

The problem isn't in the definition of add_to_cart, controller action methods don't take ruby arguments. So...

Somewhere some other code. A view? A model method, some other controller method is calling add_to_cart with a parameter.

That's why the error page should show a stack trace, doesn't it? That should point you to the code which called add_to_cart which is the code which needs to be fixed.

Hey Rick,

First of all, thank you for your reply, it finally works! So what did I do?I analyzed the stack trace and concluded that the problem was situated in the cart.rb At line 13:

      @items <<

It could not assign a new product to the CartItem model so I looked at the cart_item.rb: The "initialize" - which stands for constructor in Ruby I guess - was spelled wrong and that was my problem! Now it seems to work properly.

Ok! And

Well! And if this line and listed all above is present, but the error remains?

edit in cart_item.rb

// before def initialize @product = product @quantity = 1 end

// after def initialize(product)   @product = product   @quantity = 1 end