INTPYTHON-602 Fix QuerySet results of embedded model fields that have field converters

Follow up to 4633a9e.

Author: timgraham

django_mongodb_backend/operations.py

@@ -157,7 +157,9 @@ def convert_embeddedmodelfield_value(self, value, expression, connection):
             # Apply database converters to each field of the embedded model.
             for field in expression.output_field.embedded_model._meta.fields:
                 field_expr = Expression(output_field=field)
-                converters = connection.ops.get_db_converters(field_expr)
+                converters = connection.ops.get_db_converters(
+                    field_expr
+                ) + field_expr.get_db_converters(connection)
                 for converter in converters:
                     value[field.attname] = converter(value[field.attname], field_expr, connection)
         return value

tests/model_fields_/test_embedded_model.py

@@ -71,6 +71,11 @@ def test_save_load_null(self):
         obj = Holder.objects.get()
         self.assertIsNone(obj.data)
 
+    def test_save_load_json(self):
+        obj = Holder.objects.create(data=Data(json_value={"a": 1}))
+        obj.refresh_from_db()
+        self.assertEqual(obj.data.json_value, {"a": 1})
+
     def test_pre_save(self):
         """Field.pre_save() is called on embedded model fields."""
         obj = Holder.objects.create(data=Data())