#204: Error with learning_objects check

app/policies/learning_object_policy.rb

@@ -38,9 +38,10 @@ class LearningObjectPolicy < ApplicationPolicy
   end
 
   def show?
-    return record if record.published? || user_can_moderate?
+    return record if record.published? || ( !user.nil? && user_can_moderate? )
     return record if user == record.publisher
     ## TODO: falta verificar se o +record.publisher+ é uma instituição e +user+ faz parte
+    # => return owner.users.include?(user) if owner.is_a?(Institution)  (???)
   end
 
   def index?