1 files changed, 17 insertions, 4 deletions
diff --git a/activerecord/lib/active_record/attribute.rb b/activerecord/lib/active_record/attribute.rb
index 73bb059495..73dd3fa041 100644
--- a/activerecord/lib/active_record/attribute.rb
+++ b/activerecord/lib/active_record/attribute.rb
@@ -43,7 +43,7 @@ module ActiveRecord
     end
 
     def value_for_database
-      type.type_cast_for_database(value)
+      type.serialize(value)
     end
 
     def changed_from?(old_value)
@@ -66,6 +66,10 @@ module ActiveRecord
       self.class.with_cast_value(name, value, type)
     end
 
+    def with_type(type)
+      self.class.new(name, value_before_type_cast, type)
+    end
+
     def type_cast(*)
       raise NotImplementedError
     end
@@ -88,6 +92,11 @@ module ActiveRecord
         value_before_type_cast == other.value_before_type_cast &&
         type == other.type
     end
+    alias eql? ==
+
+    def hash
+      [self.class, name, value_before_type_cast, type].hash
+    end
 
     protected
 
@@ -99,13 +108,13 @@ module ActiveRecord
 
     class FromDatabase < Attribute # :nodoc:
       def type_cast(value)
-        type.type_cast_from_database(value)
+        type.deserialize(value)
       end
     end
 
     class FromUser < Attribute # :nodoc:
       def type_cast(value)
-        type.type_cast_from_user(value)
+        type.cast(value)
       end
 
       def came_from_user?
@@ -132,6 +141,10 @@ module ActiveRecord
         nil
       end
 
+      def with_type(type)
+        self.class.with_cast_value(name, nil, type)
+      end
+
       def with_value_from_database(value)
         raise ActiveModel::MissingAttributeError, "can't write unknown attribute `#{name}`"
       end
@@ -156,6 +169,6 @@ module ActiveRecord
         false
       end
     end
-    private_constant :FromDatabase, :FromUser, :Null, :Uninitialized
+    private_constant :FromDatabase, :FromUser, :Null, :Uninitialized, :WithCastValue
   end
 end