Fixed #17542 -- Gracefully handle errors when checking if the values of a SelectDateWidget has changed if it's not required. Thanks, pigletto.

git-svn-id: http://code.djangoproject.com/svn/django/trunk@17436 bcc190cf-cafb-0310-a4f2-bffc1f526a37

1 files changed, 6 insertions, 3 deletions

diff --git a/django/forms/extras/widgets.py b/django/forms/extras/widgets.py
index 4fb4869e68..65d6bf15f5 100644
--- a/django/forms/extras/widgets.py
+++ b/django/forms/extras/widgets.py
@@ -136,6 +136,9 @@ class SelectDateWidget(Widget):
         return select_html
 
     def _has_changed(self, initial, data):
-        input_format = get_format('DATE_INPUT_FORMATS')[0]
-        data = datetime_safe.datetime.strptime(data, input_format).date()
-        return super(SelectDateWidget, self)._has_changed(initial, data)
\ No newline at end of file
+        try:
+            input_format = get_format('DATE_INPUT_FORMATS')[0]
+            data = datetime_safe.datetime.strptime(data, input_format).date()
+        except (TypeError, ValueError):
+            pass
+        return super(SelectDateWidget, self)._has_changed(initial, data)