Detect protect attributes for rails 4

lib/paper_trail.rb

@@ -2,7 +2,6 @@ require 'paper_trail/cleaner'
 require 'paper_trail/config'
 require 'paper_trail/controller'
 require 'paper_trail/has_paper_trail'
-require 'paper_trail/version'
 
 require 'paper_trail/serializers/yaml'
 require 'paper_trail/serializers/json'
@@ -22,6 +21,10 @@ module PaperTrail
     !!PaperTrail.config.enabled
   end
 
+  def self.protected_attributes?
+    Rails.version < '4' || defined?(ProtectedAttributes)
+  end
+
   # Returns `true` if PaperTrail is enabled for the request, `false` otherwise.
   #
   # See `PaperTrail::Controller#paper_trail_enabled_for_controller`.
@@ -101,6 +104,9 @@ module PaperTrail
 
 end
 
+require 'paper_trail/version'
+
+
 
 ActiveSupport.on_load(:active_record) do
   include PaperTrail::Model

lib/paper_trail/version.rb

@@ -2,7 +2,7 @@ module PaperTrail
   class Version < ActiveRecord::Base
     belongs_to :item, :polymorphic => true
     validates_presence_of :event
-    attr_accessible :item_type, :item_id, :event, :whodunnit, :object, :object_changes if respond_to?(:attr_accessible)
+    attr_accessible :item_type, :item_id, :event, :whodunnit, :object, :object_changes if ::PaperTrail.protected_attributes?
 
     after_create :enforce_version_limit!
 

test/dummy/config/initializers/paper_trail.rb

@@ -1,5 +1,5 @@
 module PaperTrail
   class Version < ActiveRecord::Base
-    attr_accessible :created_at, :updated_at, :answer, :action, :question, :article_id, :ip, :user_agent, :title if respond_to?(:attr_accessible)
+    attr_accessible :created_at, :updated_at, :answer, :action, :question, :article_id, :ip, :user_agent, :title if ::PaperTrail.protected_attributes?
   end
 end