Fixed #31762 -- Made reloading the database for tests use the base manager.

Co-authored-by: Eugene Kulak <kulak.eugene@gmail.com>

django/db/backends/base/creation.py

@@ -122,7 +122,7 @@ class BaseDatabaseCreation:
                             model._meta.can_migrate(self.connection) and
                             router.allow_migrate_model(self.connection.alias, model)
                         ):
-                            queryset = model._default_manager.using(
+                            queryset = model._base_manager.using(
                                 self.connection.alias,
                             ).order_by(model._meta.pk.name)
                             yield from queryset.iterator()

tests/backends/base/test_creation.py

@@ -1,4 +1,5 @@
 import copy
+import datetime
 from unittest import mock
 
 from django.db import DEFAULT_DB_ALIAS, connection, connections
@@ -10,6 +11,7 @@ from django.test.utils import override_settings
 
 from ..models import (
     CircularA, CircularB, Object, ObjectReference, ObjectSelfReference,
+    SchoolClass,
 )
 
 
@@ -175,3 +177,14 @@ class TestDeserializeDbFromString(TransactionTestCase):
         obj_b = CircularB.objects.get()
         self.assertEqual(obj_a.obj, obj_b)
         self.assertEqual(obj_b.obj, obj_a)
+
+    def test_serialize_db_to_string_base_manager(self):
+        SchoolClass.objects.create(year=1000, last_updated=datetime.datetime.now())
+        with mock.patch('django.db.migrations.loader.MigrationLoader') as loader:
+            # serialize_db_to_string() serializes only migrated apps, so mark
+            # the backends app as migrated.
+            loader_instance = loader.return_value
+            loader_instance.migrated_apps = {'backends'}
+            data = connection.creation.serialize_db_to_string()
+        self.assertIn('"model": "backends.schoolclass"', data)
+        self.assertIn('"year": 1000', data)

tests/backends/models.py

@@ -21,11 +21,18 @@ class Person(models.Model):
         return '%s %s' % (self.first_name, self.last_name)
 
 
+class SchoolClassManager(models.Manager):
+    def get_queryset(self):
+        return super().get_queryset().exclude(year=1000)
+
+
 class SchoolClass(models.Model):
     year = models.PositiveIntegerField()
     day = models.CharField(max_length=9, blank=True)
     last_updated = models.DateTimeField()
 
+    objects = SchoolClassManager()
+
 
 class VeryLongModelNameZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZ(models.Model):
     primary_key_is_quite_long_zzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzz = models.AutoField(primary_key=True)