uses new hash syntax by default

config/routes.rb

@@ -1,6 +1,6 @@
 Rails.application.routes.draw do
-  devise_for :users, :controllers => { registrations: 'registrations' }
-  
+  devise_for :users, controllers: { registrations: 'registrations' }
+
   # The priority is based upon order of creation: first created -> highest priority.
   # See how all your routes lay out with "rake routes".