Filtering on a field named `negate` raises a TypeError

[Aaron Kirkbride]

Filtering on a model with a field named negate raises a TypeError.

For example:

class Foo(models.Model):
    negate = models.BooleanField()

Foo.objects.filter(negate=True)

raises TypeError: _filter_or_exclude() got multiple values for argument 'negate'

negate is not documented as a reserved argument for .filter(). I'm currently using .filter(negate__exact=True) as a workaround.

[Simon Charette]

We should either document this limitation or change _filter_or_exclude and friends signature from (negate, *args, **kwargs) to (negate, args, kwargs).

I think the second approach is favourable as there's not much benefits in using arguments unpacking in these private methods as long as the public methods filter and exclude preserve their signature.

[Simon Charette]

Aaron, would you be interested in submitting a PR with the changes below plus a regression test in tests/query/tests.py?

django/db/models/query.py

@@ -204 +204 @@
     def query(self):
         if self._deferred_filter:
             negate, args, kwargs = self._deferred_filter
-            self._filter_or_exclude_inplace(negate, *args, **kwargs)
+            self._filter_or_exclude_inplace(negate, args, kwargs)
             self._deferred_filter = None
         return self._query
 
@@ -939 +939 @@
         set.
         """
         self._not_support_combined_queries('filter')
-        return self._filter_or_exclude(False, *args, **kwargs)
+        return self._filter_or_exclude(False, args, kwargs)
 
     def exclude(self, *args, **kwargs):
         """
@@ -947 +947 @@
         set.
         """
         self._not_support_combined_queries('exclude')
-        return self._filter_or_exclude(True, *args, **kwargs)
+        return self._filter_or_exclude(True, args, kwargs)
 
-    def _filter_or_exclude(self, negate, *args, **kwargs):
+    def _filter_or_exclude(self, negate, args, kwargs):
         if args or kwargs:
             assert not self.query.is_sliced, \
                 "Cannot filter a query once a slice has been taken."
@@ -959 +959 @@
             self._defer_next_filter = False
             clone._deferred_filter = negate, args, kwargs
         else:
-            clone._filter_or_exclude_inplace(negate, *args, **kwargs)
+            clone._filter_or_exclude_inplace(negate, args, kwargs)
         return clone
 
-    def _filter_or_exclude_inplace(self, negate, *args, **kwargs):
+    def _filter_or_exclude_inplace(self, negate, args, kwargs):
         if negate:
             self._query.add_q(~Q(*args, **kwargs))
         else:
@@ -983 +983 @@
             clone.query.add_q(filter_obj)
             return clone
         else:
-            return self._filter_or_exclude(False, **filter_obj)
+            return self._filter_or_exclude(False, args=(), kwargs=filter_obj)
 
     def _combinator_query(self, combinator, *other_qs, all=False):
         # Clone the query to inherit the select list and everything

[Aaron Kirkbride]

Replying to Simon Charette:

Aaron, would you be interested in submitting a PR with the changes below plus a regression test in tests/query/tests.py?

Sure! I can do that this evening. Thanks for the patch :)

[Aaron Kirkbride]

Replying to Hasan Ramezani:

Thanks Hasan for creating the PR :) Sorry I didn't get round to this earlier.

[Mariusz Felisiak <felisiak.mariusz@…>]

In 9c9a3fe1:

Fixed #31783 -- Fixed crash when filtering againts "negate" field.

Thanks Simon Charette for the initial patch.