Integration Testing: xml_http_request

I was referring to Agile Web Development with Rails book to implement the Integration testing. And as per the book it

xml_http_request "/store/add_to_cart" , :id => ruby_book.id

and strangely I was getting syntax error. Seems the book did miss out another parameter which would define the method type. Referring to online documentation, made things clear.

xml_http_request(request_method, path, parameters = nil, headers = nil)

Performs an XMLHttpRequest request with the given parameters, mirroring a request from the Prototype library.

The request_method is :get, :post, :put, :delete or :head; the parameters are nil, a hash, or a url-encoded or multipart string; the headers are a hash. Keys are automatically upcased and prefixed with ‘HTTP_’ if not already.