Ticket #10121: 10121.diff

django/db/models/fields/files.py

@@ -213 +213 @@
     def generate_filename(self, instance, filename):
         return os.path.join(self.get_directory_name(), self.get_filename(filename))
 
+    def save_form_data(self, instance, data):
+        if data and isinstance(data, UploadedFile):
+            getattr(instance, self.name).save(data.name, data, save=False)
+
     def formfield(self, **kwargs):
         defaults = {'form_class': forms.FileField}
         # If a file has been provided previously, then the form doesn't require

tests/modeltests/model_forms/models.py

@@ -1030 +1030 @@
 >>> instance.file
 <FieldFile: tests/test3.txt>
 
+# Instance can be edited w/out re-uploading the file and existing file should be preserved.
+
+>>> f = TextFileForm(data={'description': u'New Description'}, instance=instance)
+>>> f.fields['file'].required = False
+>>> f.is_valid()
+True
+>>> instance = f.save()
+>>> instance.description
+u'New Description'
+>>> instance.file
+<FieldFile: tests/test3.txt>
+
 # Delete the current file since this is not done by Django.
 >>> instance.file.delete()
 >>> instance.delete()