Fixed #29595 -- Allowed using timedelta in migrations questioner.

Refs #29600 -- Removed usage of django.utils.datetime_safe in migrations.

django/db/migrations/questioner.py

+import datetime
 import importlib
 import os
 import sys
 
 from django.apps import apps
 from django.db.models.fields import NOT_PROVIDED
-from django.utils import datetime_safe, timezone
+from django.utils import timezone
 
 from .loader import MigrationLoader
 
@@ -135,7 +136,7 @@ class InteractiveMigrationQuestioner(MigrationQuestioner):
                 sys.exit(1)
             else:
                 try:
-                    return eval(code, {}, {"datetime": datetime_safe, "timezone": timezone})
+                    return eval(code, {}, {'datetime': datetime, 'timezone': timezone})
                 except (SyntaxError, NameError) as e:
                     print("Invalid input: %s" % e)
 

django/db/migrations/serializer.py

@@ -12,7 +12,6 @@ import uuid
 from django.db import models
 from django.db.migrations.operations.base import Operation
 from django.db.migrations.utils import COMPILED_REGEX_TYPE, RegexObject
-from django.utils import datetime_safe
 from django.utils.functional import LazyObject, Promise
 from django.utils.timezone import utc
 from django.utils.version import get_docs_version
@@ -46,25 +45,21 @@ class BaseSimpleSerializer(BaseSerializer):
         return repr(self.value), set()
 
 
-class DatetimeSerializer(BaseSerializer):
+class DateTimeSerializer(BaseSerializer):
+    """For datetime.*, except datetime.datetime."""
+    def serialize(self):
+        return repr(self.value), {'import datetime'}
+
+
+class DatetimeDatetimeSerializer(BaseSerializer):
+    """For datetime.datetime."""
     def serialize(self):
         if self.value.tzinfo is not None and self.value.tzinfo != utc:
             self.value = self.value.astimezone(utc)
-        value_repr = repr(self.value).replace("<UTC>", "utc")
-        if isinstance(self.value, datetime_safe.datetime):
-            value_repr = "datetime.%s" % value_repr
         imports = ["import datetime"]
         if self.value.tzinfo is not None:
             imports.append("from django.utils.timezone import utc")
-        return value_repr, set(imports)
-
-
-class DateSerializer(BaseSerializer):
-    def serialize(self):
-        value_repr = repr(self.value)
-        if isinstance(self.value, datetime_safe.date):
-            value_repr = "datetime.%s" % value_repr
-        return value_repr, {"import datetime"}
+        return repr(self.value).replace('<UTC>', 'utc'), set(imports)
 
 
 class DecimalSerializer(BaseSerializer):
@@ -246,19 +241,6 @@ class SettingsReferenceSerializer(BaseSerializer):
         return "settings.%s" % self.value.setting_name, {"from django.conf import settings"}
 
 
-class TimedeltaSerializer(BaseSerializer):
-    def serialize(self):
-        return repr(self.value), {"import datetime"}
-
-
-class TimeSerializer(BaseSerializer):
-    def serialize(self):
-        value_repr = repr(self.value)
-        if isinstance(self.value, datetime_safe.time):
-            value_repr = "datetime.%s" % value_repr
-        return value_repr, {"import datetime"}
-
-
 class TupleSerializer(BaseSequenceSerializer):
     def _format(self):
         # When len(value)==0, the empty tuple should be serialized as "()",
@@ -322,13 +304,9 @@ def serializer_factory(value):
     if isinstance(value, enum.Enum):
         return EnumSerializer(value)
     if isinstance(value, datetime.datetime):
-        return DatetimeSerializer(value)
-    if isinstance(value, datetime.date):
-        return DateSerializer(value)
-    if isinstance(value, datetime.time):
-        return TimeSerializer(value)
-    if isinstance(value, datetime.timedelta):
-        return TimedeltaSerializer(value)
+        return DatetimeDatetimeSerializer(value)
+    if isinstance(value, (datetime.date, datetime.timedelta, datetime.time)):
+        return DateTimeSerializer(value)
     if isinstance(value, SettingsReference):
         return SettingsReferenceSerializer(value)
     if isinstance(value, float):

tests/migrations/test_questioner.py

-from django.db.migrations.questioner import MigrationQuestioner
+import datetime
+from unittest import mock
+
+from django.db.migrations.questioner import (
+    InteractiveMigrationQuestioner, MigrationQuestioner,
+)
 from django.test import SimpleTestCase
-from django.test.utils import override_settings
+from django.test.utils import captured_stdout, override_settings
 
 
 class QuestionerTests(SimpleTestCase):
@@ -11,3 +16,10 @@ class QuestionerTests(SimpleTestCase):
     def test_ask_initial_with_disabled_migrations(self):
         questioner = MigrationQuestioner()
         self.assertIs(False, questioner.ask_initial('migrations'))
+
+    @mock.patch('builtins.input', return_value='datetime.timedelta(days=1)')
+    def test_timedelta_default(self, mock):
+        questioner = InteractiveMigrationQuestioner()
+        with captured_stdout():
+            value = questioner._ask_default()
+        self.assertEqual(value, datetime.timedelta(days=1))

tests/migrations/test_writer.py

@@ -19,7 +19,6 @@ from django.db.migrations.writer import (
     MigrationWriter, OperationWriter, SettingsReference,
 )
 from django.test import SimpleTestCase
-from django.utils import datetime_safe
 from django.utils.deconstruct import deconstructible
 from django.utils.functional import SimpleLazyObject
 from django.utils.timezone import get_default_timezone, get_fixed_timezone, utc
@@ -364,20 +363,6 @@ class WriterTests(SimpleTestCase):
             )
         )
 
-    def test_serialize_datetime_safe(self):
-        self.assertSerializedResultEqual(
-            datetime_safe.date(2014, 3, 31),
-            ("datetime.date(2014, 3, 31)", {'import datetime'})
-        )
-        self.assertSerializedResultEqual(
-            datetime_safe.time(10, 25),
-            ("datetime.time(10, 25)", {'import datetime'})
-        )
-        self.assertSerializedResultEqual(
-            datetime_safe.datetime(2014, 3, 31, 16, 4, 31),
-            ("datetime.datetime(2014, 3, 31, 16, 4, 31)", {'import datetime'})
-        )
-
     def test_serialize_fields(self):
         self.assertSerializedFieldEqual(models.CharField(max_length=255))
         self.assertSerializedResultEqual(