Pundit policy_scope error: undefined method `admin?' for nil:NilClass

Question

Running into something I don\'t understand with Pundit,

Using Rails 4.2.5.1, Pundit 1.1.0 with Devise for authentication.

I\'m trying to use a policy scope f

Answer 1

This happens because there is no user when you are not logged in. (Probably to user variable nil value is assigned somewhere, so you are trying to call admin? method on nil object)

If you use ruby 2.3.0 or newer you had better use safe navigation

  if user&.admin?
    scope.order('id DESC')
  else
    scope.where('published: true')
  end

If you user other ruby version

if user.try(:admin?)
  scope.order(id: :desc)
else
  scope.where(published: true)
end

Answer 2

You can use try:

if user.try(:admin?)
  # do something
end

http://api.rubyonrails.org/v4.2.5/classes/Object.html#method-i-try