Fixed is_paranoid super from singleton method bug

vendor/plugins/is_paranoid/lib/is_paranoid.rb

@@ -1,8 +1,10 @@
-require 'active_support/concern'
 require 'active_record'
 
 module IsParanoid
-  extend ActiveSupport::Concern
+
+  def self.included(base)
+    base.extend(ClassMethods)
+  end
 
   module ClassMethods
     # Call this in your model to enable all the safety-net goodness
@@ -13,86 +15,90 @@ module ClassMethods
     #    is_paranoid
     #  end
     def is_paranoid
-      class_eval do
+      unless included_modules.include?(InstanceMethods)
+        extend SingletonMethods
+        include InstanceMethods
+
         # This is the real magic.  All calls made to this model will
         # append the conditions deleted_at => nil.  Exceptions require
         # using with_destroyed_scope (see self.delete_all,
         # self.count_with_destroyed, and self.find_with_destroyed )
         default_scope where(:deleted_at => nil)
 
-        class << self
-          def destroyed
-            unscoped.where('deleted_at IS NOT NULL')
-          end
-
-          # Actually delete the model, bypassing the safety net.  Because
-          # this method is called internally by Model.delete(id) and on the
-          # delete method in each instance, we don't need to specify those
-          # methods separately
-          def delete_all conditions = nil
-            with_exclusive_scope { super conditions }
-          end
-
-          # Return a count that includes the soft-deleted models.
-          def count_with_destroyed
-            unscoped.count
-          end
-
-          # Perform a count only on destroyed instances.
-          def count_only_destroyed
-            destroyed.count
-          end
-
-          # Return instances of all models matching the query regardless
-          # of whether or not they have been soft-deleted.
-          def find_with_destroyed *args
-            unscoped.find(*args)
-          end
-
-          # Returns true if the requested record exists, even if it has
-          # been soft-deleted.
-          def exists_with_destroyed? *args
-            unscoped.exists?(*args)
-          end
-
-          # Returns true if the requested record has been soft-deleted.
-          def exists_only_destroyed? *args
-            destroyed.exists?(*args)
-          end
-        end
-
         # Override the default destroy to allow us to flag deleted_at.
         # This preserves the before_destroy and after_destroy callbacks.
         # Because this is also called internally by Model.destroy_all and
         # the Model.destroy(id), we don't need to specify those methods
         # separately.
         alias_method :destroy!, :destroy
+      end
+    end
+  end
+
+  module SingletonMethods
+    def destroyed
+      unscoped.where('deleted_at IS NOT NULL')
+    end
+
+    # Actually delete the model, bypassing the safety net.  Because
+    # this method is called internally by Model.delete(id) and on the
+    # delete method in each instance, we don't need to specify those
+    # methods separately
+    def delete_all(conditions = nil)
+      with_exclusive_scope { super conditions }
+    end
+
+    # Return a count that includes the soft-deleted models.
+    def count_with_destroyed
+      unscoped.count
+    end
+
+    # Perform a count only on destroyed instances.
+    def count_only_destroyed
+      destroyed.count
+    end
+
+    # Return instances of all models matching the query regardless
+    # of whether or not they have been soft-deleted.
+    def find_with_destroyed(*args)
+      unscoped.find(*args)
+    end
+
+    # Returns true if the requested record exists, even if it has
+    # been soft-deleted.
+    def exists_with_destroyed?(*args)
+      unscoped.exists?(*args)
+    end
+
+    # Returns true if the requested record has been soft-deleted.
+    def exists_only_destroyed?(*args)
+      destroyed.exists?(*args)
+    end
+  end
 
-        def destroy
-          _run_destroy_callbacks do
-            set_deleted_at(current_time_from_proper_timezone)
-          end
-        end
-
-        # Set deleted_at flag on a model to nil, effectively undoing the
-        # soft-deletion.
-        def restore
-          set_deleted_at(nil)
-        end
-
-        # Has this model been soft-deleted?
-        def destroyed?
-          !deleted_at.nil?
-        end
-
-        protected
-
-          def set_deleted_at(value)            
-            self.class.unscoped.update_all({:deleted_at => value}, {:id => self.id})
-            self.deleted_at = value
-          end
+  module InstanceMethods
+    def destroy
+      _run_destroy_callbacks do
+        set_deleted_at(current_time_from_proper_timezone)
       end
     end
+
+    # Set deleted_at flag on a model to nil, effectively undoing the
+    # soft-deletion.
+    def restore
+      set_deleted_at(nil)
+    end
+
+    # Has this model been soft-deleted?
+    def destroyed?
+      !deleted_at.nil?
+    end
+  protected
+
+    def set_deleted_at(value)
+      self.class.unscoped.update_all({:deleted_at => value}, {:id => self.id})
+      self.deleted_at = value
+    end
   end
 end