Ticket #8974: 8974.patch

django/forms/models.py

@@ -648 +648 @@
         try:
             key = self.to_field_name or 'pk'
             value = self.queryset.get(**{key: value})
-        except self.queryset.model.DoesNotExist:
+        except (self.queryset.model.DoesNotExist, ValueError):
             raise ValidationError(self.error_messages['invalid_choice'])
         return value
 
@@ -680 +680 @@
         for val in value:
             try:
                 obj = self.queryset.get(pk=val)
-            except self.queryset.model.DoesNotExist:
+            except (self.queryset.model.DoesNotExist, ValueError):
                 raise ValidationError(self.error_messages['invalid_choice'] % val)
             else:
                 final_values.append(obj)