Force Spree.user_class to be set to Spree::User to fix the infamous error:

rake aborted!
Association named 'spree_roles' was not found; perhaps you misspelled it?

It's tripped me up WAY too many times now.

Author: radar

config/initializers/spree.rb

@@ -1 +1 @@
-Spree.user_class = "Spree::User"
+

lib/spree/auth/engine.rb

@@ -18,6 +18,10 @@ def self.activate
         ApplicationController.send :include, Spree::AuthenticationHelpers
       end
 
+      initializer "spree_auth_devise.set_user_class", :after => :load_config_initializers do
+        Spree.user_class = "Spree::User"
+      end
+
       config.to_prepare &method(:activate).to_proc
     end
   end