Fixed #36722 -- Allowed selecting zero in MySQL auto fields using expressions.

django/db/models/fields/__init__.py

@@ -2810,10 +2810,13 @@ class AutoFieldMixin:
         pass
 
     def get_db_prep_value(self, value, connection, prepared=False):
-        if not prepared:
+        return value if prepared else self.get_prep_value(value)
-            value = self.get_prep_value(value)
+
-            value = connection.ops.validate_autopk_value(value)
+    def get_db_prep_save(self, value, connection):
-        return value
+        if hasattr(value, "as_sql"):
+            return value
+        value = connection.ops.validate_autopk_value(value)
+        return self.get_db_prep_value(value, connection=connection, prepared=False)
 
     def contribute_to_class(self, cls, name, **kwargs):
         if cls._meta.auto_field:

tests/backends/tests.py

@@ -19,6 +19,7 @@ from django.db import (
 from django.db.backends.base.base import BaseDatabaseWrapper
 from django.db.backends.signals import connection_created
 from django.db.backends.utils import CursorWrapper
+from django.db.models import BigAutoField, Value
 from django.db.models.sql.constants import CURSOR
 from django.test import (
     TestCase,
@@ -966,7 +967,7 @@ class ThreadTests(TransactionTestCase):
             connection.dec_thread_sharing()
 
 
-class MySQLPKZeroTests(TestCase):
+class MySQLAutoPKZeroTests(TestCase):
     """
     Zero as id for AutoField should raise exception in MySQL, because MySQL
     does not allow zero for autoincrement primary key if the
@@ -975,8 +976,15 @@ class MySQLPKZeroTests(TestCase):
 
     @skipIfDBFeature("allows_auto_pk_0")
     def test_zero_as_autoval(self):
-        with self.assertRaises(ValueError):
+        msg = "The database backend does not accept 0 as a value for AutoField."
+        with self.assertRaisesMessage(ValueError, msg):
             Square.objects.create(id=0, root=0, square=1)
+        with self.assertRaisesMessage(ValueError, msg):
+            Square.objects.create(id=Value(0, BigAutoField()), root=0, square=1)
+
+    @skipIfDBFeature("allows_auto_pk_0")
+    def test_no_error_when_filtering_with_expression(self):
+        self.assertSequenceEqual(Square.objects.filter(id=Value(0, BigAutoField())), ())
 
 
 class DBConstraintTestCase(TestCase):

tests/model_fields/test_integerfield.py

@@ -198,7 +198,7 @@ class IntegerFieldTests(TestCase):
             (TypeError, {}),
             (TypeError, set()),
             (TypeError, object()),
-            (TypeError, complex()),
+            (TypeError, complex(0, 1)),
             (ValueError, "non-numeric string"),
             (ValueError, b"non-numeric byte-string"),
         ]