Rspec prevent method from being called - ruby-on-rails

Question

I am testing a controller method for creating new orders (e-commerce-like app). If user is present in the system, he should be redirected to new_user_session_path, else to new_order_path. Simple as that.
This is my orders_controller.rb
def new
if !User.where(phone: params[:phone]).blank? && !user_signed_in?
redirect_to new_user_session_path()
flash[:info] = "Already present"
else
#order = Order.new
#menu = Menu.find(params[:menu_id])
#menu_price = #menu.calculate_price(#menu, params)
end
end
In my app, I need the calculate_price method to be called, because it calculates the overall price given the params. But in my test, I just want to ensure, that the redirect is correct.
Right now I'm getting errors like (they are sourced inside the Menu.rb file, since calculate_price is called) :
Front::OrdersController#new redirects user to new order page if user is not present in the system
Failure/Error: menu_price_change = menu_amount.split(",")[1].gsub(" ","").gsub("]",'')
NoMethodError:
undefined method `split' for nil:NilClass
This is my spec file:
require 'rails_helper'
describe Front::OrdersController, type: :controller do
describe '#new' do
# Set up dummy menu
let (:menu) { Menu.create() }
it "redirects user to sign up page if user is present in the system" do
user = User.create(name: "Bob", password: "bobspassword", phone: "[phone]")
get :new, params: { phone: user.phone }
expect(response).to redirect_to(new_user_session_path(phone: user.phone))
end
it "redirects user to new order page if user is not present in the system" do
non_present_phone = "[phone]"
get :new, params: { phone: non_present_phone, menu_id: menu.id}
expect(response).to redirect_to(new_order_path)
end
end
end
Of course I could provide all the params, but there is a pretty big amount of them and besides, I just want to test the correct redirect. As far as I know, mocks and subs are useful in this case, when you want to explicitly test the methods. But in my case, I want to - somehow - omit them. How can I ensure that behaviour?

Answer 1

So you want just to test redirects and the errors occured when calculate_price method executes bother you. Why don't you just stub that method? Your spec file might be like this:
require 'rails_helper'
describe Front::OrdersController, type: :controller do
describe '#new' do
# Set up dummy menu
let (:menu) { Menu.create() }
# Check this out
before do
allow_any_instance_of(Menu).to receive(:calculate_price)
# or if you need certain value
allow_any_instance_of(Menu).to receive(:calculate_price).and_return(your_value)
end
it "redirects user to sign up page if user is present in the system" do
user = User.create(name: "Bob", password: "bobspassword", phone: "[phone]")
get :new, params: { phone: user.phone }
expect(response).to redirect_to(new_user_session_path(phone: user.phone))
end
it "redirects user to new order page if user is not present in the system" do
non_present_phone = "[phone]"
get :new, params: { phone: non_present_phone, menu_id: menu.id}
expect(response).to redirect_to(new_order_path)
end
end
end