1 files changed, 18 insertions, 0 deletions
diff --git a/activerecord/lib/active_record/attribute_methods/serialization.rb b/activerecord/lib/active_record/attribute_methods/serialization.rb
index 00023b0b6c..deb89f3ac1 100644
--- a/activerecord/lib/active_record/attribute_methods/serialization.rb
+++ b/activerecord/lib/active_record/attribute_methods/serialization.rb
@@ -90,6 +90,14 @@ module ActiveRecord
         end
       end
 
+      def _field_changed?(attr, old, value)
+        if self.class.serialized_attributes.include?(attr)
+          old != value
+        else
+          super
+        end
+      end
+
       def read_attribute_before_type_cast(attr_name)
         if serialized_attributes.include?(attr_name)
           super.unserialized_value
@@ -97,6 +105,16 @@ module ActiveRecord
           super
         end
       end
+
+      def attributes_before_type_cast
+        super.dup.tap do |attributes|
+          self.class.serialized_attributes.each_key do |key|
+            if attributes.key?(key)
+              attributes[key] = attributes[key].unserialized_value
+            end
+          end
+        end
+      end
     end
   end
 end