1 files changed, 42 insertions, 0 deletions
diff --git a/activerecord/lib/active_record/attribute_methods/serialization.rb b/activerecord/lib/active_record/attribute_methods/serialization.rb
new file mode 100644
index 0000000000..686754fbc2
--- /dev/null
+++ b/activerecord/lib/active_record/attribute_methods/serialization.rb
@@ -0,0 +1,42 @@
+module ActiveRecord
+  module AttributeMethods
+    module Serialization
+      extend ActiveSupport::Concern
+
+      module ClassMethods
+        def define_method_attribute(attr_name)
+          if serialized_attributes.include?(attr_name)
+            generated_attribute_methods.module_eval(<<-CODE, __FILE__, __LINE__)
+              def _#{attr_name}
+                @attributes_cache['#{attr_name}'] ||= @attributes['#{attr_name}']
+              end
+              alias #{attr_name} _#{attr_name}
+            CODE
+          else
+            super
+          end
+        end
+
+        def cacheable_column?(column)
+          serialized_attributes.include?(column.name) || super
+        end
+      end
+
+      def type_cast_attribute(column, value)
+        coder = self.class.serialized_attributes[column.name]
+
+        if column.text? && coder
+          unserialized_object = coder.load(@attributes[column.name])
+
+          if @attributes.frozen?
+            unserialized_object
+          else
+            @attributes[column.name] = unserialized_object
+          end
+        else
+          super
+        end
+      end
+    end
+  end
+end