Fixed setting callable choices on Django <5.0. (#1648)

* Failing test for ChoiceField eagerly evaluating choices
* Fixed regression in choices setter for Django 4.2.

---------

Co-authored-by: Carlton Gibson <carlton.gibson@noumenal.es>

django_filters/fields.py

@@ -275,13 +275,13 @@ def choices(self):
     def choices(self, value):
         if DJANGO_50:
             value = self.iterator(self, value)
+            # Simple `super()` syntax for calling a parent property setter is
+            # unsupported. See https://github.com/python/cpython/issues/59170
+            super(ChoiceIteratorMixin, self.__class__).choices.__set__(self, value)
         else:
             super()._set_choices(value)
             value = self.iterator(self, self._choices)
-
-        # Simple `super()` syntax for calling a parent property setter is
-        # unsupported. See https://github.com/python/cpython/issues/59170
-        super(ChoiceIteratorMixin, self.__class__).choices.__set__(self, value)
+            self._choices = self.widget.choices = value
 
 
 # Unlike their Model* counterparts, forms.ChoiceField and forms.MultipleChoiceField do not set empty_label

tests/test_fields.py

@@ -12,6 +12,7 @@
 from django_filters.fields import (
     BaseCSVField,
     BaseRangeField,
+    ChoiceField,
     DateRangeField,
     DateTimeRangeField,
     IsoDateTimeField,
@@ -58,6 +59,14 @@ def test_clean(self):
         self.assertIsNone(f.clean([]))
 
 
+class ChoiceFieldTests(TestCase):
+    def test_callable_choices_is_lazy(self):
+        def choices():
+            self.fail("choices should not be called during initialization")
+
+        ChoiceField(choices=choices)
+
+
 class DateRangeFieldTests(TestCase):
     def test_field(self):
         f = DateRangeField()