Rspec & Rails: how to test controller for 404 error? It gives "no route matches" error instead of 404

I want to test that application responds with 404 error and have code: ``` require 'spec_helper' describe Admin::UsersController do describe "GET new" do before { get :new } it { should respond_with(404) } end end ``` My routes: ``` namespace :admin, module: :admin do resources :users, except: [:new, :create] end ``` When I ran local server in production mode it really responds with 404 error, but when I run rspec test, it gives me the following: ``` 1) Admin::UsersController GET new shold not be successful Failure/Error: get :new ActionController::UrlGenerationError: No route matches {:action=>"new", :controller=>"admin/users"} # ./spec/controllers/admin_users_spec.rb:7:in `block (3 levels) in <top (required)>' ``` How can I test this correctly? Updated with correct answer: ``` describe "GET new" do it "should not route to new" do expect(get: :new).not_to be_routable end end ```