module Devise::RouteSet

def finalize!
  result = super
  @devise_finalized ||= begin
    if Devise.router_name.nil? && defined?(@devise_finalized) && self != Rails.application.try(:routes)
      warn "[DEVISE] We have detected that you are using devise_for inside engine routes. " \
        "In this case, you probably want to set Devise.router_name = MOUNT_POINT, where "   \
        "MOUNT_POINT is a symbol representing where this engine will be mounted at. For "   \
        "now Devise will default the mount point to :main_app. You can explicitly set it"   \
        " to :main_app as well in case you want to keep the current behavior."
    end
    Devise.configure_warden!
    Devise.regenerate_helpers!
    true
  end
  result
end