1 files changed, 20 insertions, 0 deletions
diff --git a/activerecord/lib/active_record/attribute.rb b/activerecord/lib/active_record/attribute.rb
index 24231dc9e1..701d24da88 100644
--- a/activerecord/lib/active_record/attribute.rb
+++ b/activerecord/lib/active_record/attribute.rb
@@ -108,6 +108,22 @@ module ActiveRecord
       [self.class, name, value_before_type_cast, type].hash
     end
 
+    def init_with(coder)
+      @name = coder["name"]
+      @value_before_type_cast = coder["value_before_type_cast"]
+      @type = coder["type"]
+      @original_attribute = coder["original_attribute"]
+      @value = coder["value"] if coder.map.key?("value")
+    end
+
+    def encode_with(coder)
+      coder["name"] = name
+      coder["value_before_type_cast"] = value_before_type_cast if value_before_type_cast
+      coder["type"] = type if type
+      coder["original_attribute"] = original_attribute if original_attribute
+      coder["value"] = value if defined?(@value)
+    end
+
     protected
 
     attr_reader :original_attribute
@@ -201,6 +217,10 @@ module ActiveRecord
       def initialized?
         false
       end
+
+      def with_type(type)
+        self.class.new(name, type)
+      end
     end
     private_constant :FromDatabase, :FromUser, :Null, :Uninitialized, :WithCastValue
   end