Ticket #10244: filefield_null.patch

db/models/fields/files.py

@@ -168 +168 @@
         # in __set__.
         file = instance.__dict__[self.field.name]
 
+        if file is None:
+            return None
+
         # If this value is a string (instance.file = "path/to/file") or None
         # then we simply wrap it with the appropriate attribute class according
         # to the file field. [This is FieldFile for FileFields and
@@ -175 +178 @@
         # subclasses might also want to subclass the attribute class]. This
         # object understands how to convert a path to a file, and also how to
         # handle None.
-        if isinstance(file, six.string_types) or file is None:
+        if isinstance(file, six.string_types):
             attr = self.field.attr_class(instance, self.field, file)
             instance.__dict__[self.field.name] = attr
 
@@ -238 +241 @@
     def get_prep_value(self, value):
         "Returns field's value prepared for saving into a database."
         # Need to convert File objects provided via a form to unicode for database insertion
-        if value is None:
+        if (value is None) or not value:
             return None
         return six.text_type(value)