```ruby
# Ensure that Spree.user_class includes the UserMethods concern
# Previously these methods were injected automatically onto the class, which we
# are still doing for compatability, but with a warning.

Spree::Core::Engine.config.to_prepare do
  unless Spree.user_class.included_modules.include?(Spree::UserMethods)
    ActiveSupport::Deprecation.warn "#{Spree.user_class} must include Spree::UserMethods"
    Spree.user_class.include Spree::UserMethods
  end
end
```

Fix initialization if Spree.user_class is not set
user
```ruby
# Ensure that Spree.user_class includes the UserMethods concern
# Previously these methods were injected automatically onto the class, which we
# are still doing for compatability, but with a warning.

Spree::Core::Engine.config.to_prepare do
  if Spree.user_class && !Spree.user_class.included_modules.include?(Spree::UserMethods)
    ActiveSupport::Deprecation.warn "#{Spree.user_class} must include Spree::UserMethods"
    Spree.user_class.include Spree::UserMethods
  end
end
```
assistant