Fixed #30328 -- Fixed crash of IntegerField.validators when limit_value in a…

Fixed #30328 -- Fixed crash of IntegerField.validators when limit_value in a custom validator is callable.

AUTHORS

@@ -765,6 +765,7 @@ answer newbie questions, and generally made Django that much better:
     schwank@gmail.com
     Scot Hacker <shacker@birdhouse.org>
     Scott Barr <scott@divisionbyzero.com.au>
+    Scott Fitsimones <scott@airgara.ge>
     Scott Pashley <github@scottpashley.co.uk>
     scott@staplefish.com
     Sean Brant

django/db/models/fields/__init__.py

@@ -1792,13 +1792,25 @@ class IntegerField(Field):
         validators_ = super().validators
         internal_type = self.get_internal_type()
         min_value, max_value = connection.ops.integer_field_range(internal_type)
-        if (min_value is not None and not
-            any(isinstance(validator, validators.MinValueValidator) and
-                validator.limit_value >= min_value for validator in validators_)):
+        if min_value is not None and not any(
+            (
+                isinstance(validator, validators.MinValueValidator) and (
+                    validator.limit_value()
+                    if callable(validator.limit_value)
+                    else validator.limit_value
+                ) >= min_value
+            ) for validator in validators_
+        ):
             validators_.append(validators.MinValueValidator(min_value))
-        if (max_value is not None and not
-            any(isinstance(validator, validators.MaxValueValidator) and
-                validator.limit_value <= max_value for validator in validators_)):
+        if max_value is not None and not any(
+            (
+                isinstance(validator, validators.MaxValueValidator) and (
+                    validator.limit_value()
+                    if callable(validator.limit_value)
+                    else validator.limit_value
+                ) <= max_value
+            ) for validator in validators_
+        ):
             validators_.append(validators.MaxValueValidator(max_value))
         return validators_
 

docs/releases/2.2.1.txt

@@ -38,3 +38,7 @@ Bugfixes
   :class:`~django.core.paginator.Paginator` crashed when ``object_list`` was
   a queryset ordered or aggregated over a nested ``JSONField`` key transform
   (:ticket:`30335`).
+
+* Fixed a regression in Django 2.2 where ``IntegerField`` validation of
+  database limits crashes if ``limit_value`` attribute in a custom validator is
+  callable (:ticket:`30328`).

tests/model_fields/test_integerfield.py

@@ -98,27 +98,31 @@ class IntegerFieldTests(TestCase):
         """
         min_backend_value, max_backend_value = self.backend_range
 
-        if min_backend_value is not None:
-            min_custom_value = min_backend_value + 1
-            ranged_value_field = self.model._meta.get_field('value').__class__(
-                validators=[validators.MinValueValidator(min_custom_value)]
-            )
-            field_range_message = validators.MinValueValidator.message % {
-                'limit_value': min_custom_value,
-            }
-            with self.assertRaisesMessage(ValidationError, "[%r]" % field_range_message):
-                ranged_value_field.run_validators(min_backend_value - 1)
-
-        if max_backend_value is not None:
-            max_custom_value = max_backend_value - 1
-            ranged_value_field = self.model._meta.get_field('value').__class__(
-                validators=[validators.MaxValueValidator(max_custom_value)]
-            )
-            field_range_message = validators.MaxValueValidator.message % {
-                'limit_value': max_custom_value,
-            }
-            with self.assertRaisesMessage(ValidationError, "[%r]" % field_range_message):
-                ranged_value_field.run_validators(max_backend_value + 1)
+        for callable_limit in (True, False):
+            with self.subTest(callable_limit=callable_limit):
+                if min_backend_value is not None:
+                    min_custom_value = min_backend_value + 1
+                    limit_value = (lambda: min_custom_value) if callable_limit else min_custom_value
+                    ranged_value_field = self.model._meta.get_field('value').__class__(
+                        validators=[validators.MinValueValidator(limit_value)]
+                    )
+                    field_range_message = validators.MinValueValidator.message % {
+                        'limit_value': min_custom_value,
+                    }
+                    with self.assertRaisesMessage(ValidationError, '[%r]' % field_range_message):
+                        ranged_value_field.run_validators(min_backend_value - 1)
+
+                if max_backend_value is not None:
+                    max_custom_value = max_backend_value - 1
+                    limit_value = (lambda: max_custom_value) if callable_limit else max_custom_value
+                    ranged_value_field = self.model._meta.get_field('value').__class__(
+                        validators=[validators.MaxValueValidator(limit_value)]
+                    )
+                    field_range_message = validators.MaxValueValidator.message % {
+                        'limit_value': max_custom_value,
+                    }
+                    with self.assertRaisesMessage(ValidationError, '[%r]' % field_range_message):
+                        ranged_value_field.run_validators(max_backend_value + 1)
 
     def test_types(self):
         instance = self.model(value=0)