3 files changed, 20 insertions, 6 deletions
diff --git a/activerecord/lib/active_record/type/internal/abstract_json.rb b/activerecord/lib/active_record/type/internal/abstract_json.rb
index 097d1bd363..513c938088 100644
--- a/activerecord/lib/active_record/type/internal/abstract_json.rb
+++ b/activerecord/lib/active_record/type/internal/abstract_json.rb
@@ -17,11 +17,7 @@ module ActiveRecord
         end
 
         def serialize(value)
-          if value.is_a?(::Array) || value.is_a?(::Hash)
-            ::ActiveSupport::JSON.encode(value)
-          else
-            value
-          end
+          ::ActiveSupport::JSON.encode(value)
         end
 
         def accessor
diff --git a/activerecord/lib/active_record/type/serialized.rb b/activerecord/lib/active_record/type/serialized.rb
index 4ff0740cfb..a3a5241780 100644
--- a/activerecord/lib/active_record/type/serialized.rb
+++ b/activerecord/lib/active_record/type/serialized.rb
@@ -32,7 +32,7 @@ module ActiveRecord
 
       def changed_in_place?(raw_old_value, value)
         return false if value.nil?
-        raw_new_value = serialize(value)
+        raw_new_value = encoded(value)
         raw_old_value.nil? != raw_new_value.nil? ||
           subtype.changed_in_place?(raw_old_value, raw_new_value)
       end
@@ -52,6 +52,12 @@ module ActiveRecord
       def default_value?(value)
         value == coder.load(nil)
       end
+
+      def encoded(value)
+        unless default_value?(value)
+          coder.dump(value)
+        end
+      end
     end
   end
 end
diff --git a/activerecord/lib/active_record/type/time.rb b/activerecord/lib/active_record/type/time.rb
index 70988d84ff..7da49e43c7 100644
--- a/activerecord/lib/active_record/type/time.rb
+++ b/activerecord/lib/active_record/type/time.rb
@@ -2,6 +2,18 @@ module ActiveRecord
   module Type
     class Time < ActiveModel::Type::Time
       include Internal::Timezone
+
+      class Value < DelegateClass(::Time) # :nodoc:
+      end
+
+      def serialize(value)
+        case value = super
+        when ::Time
+          Value.new(value)
+        else
+          value
+        end
+      end
     end
   end
 end