From 59ab3fd0e9e606d7f0f7ca26609c06ee679ece97 Mon Sep 17 00:00:00 2001
From: Carlton Gibson <carlton.gibson@noumenal.es>
Date: Thu, 24 Mar 2022 11:09:55 +0100
Subject: [PATCH] Refs #32365 -- Deprecated django.utils.timezone.utc.

---
 django/utils/timezone.py        | 23 +++++++++++++++++++++--
 docs/internals/deprecation.txt  |  3 +++
 docs/ref/utils.txt              |  5 +++++
 docs/releases/4.1.txt           |  3 +++
 tests/migrations/test_writer.py |  7 +++++--
 tests/timezones/tests.py        | 13 +++++++++++++
 6 files changed, 50 insertions(+), 4 deletions(-)

diff --git a/django/utils/timezone.py b/django/utils/timezone.py
index 33c0440095..d22e358538 100644
--- a/django/utils/timezone.py
+++ b/django/utils/timezone.py
@@ -19,7 +19,7 @@ from asgiref.local import Local
 from django.conf import settings
 from django.utils.deprecation import RemovedInDjango50Warning
 
-__all__ = [
+__all__ = [  # noqa for utc RemovedInDjango50Warning.
     "utc",
     "get_fixed_timezone",
     "get_default_timezone",
@@ -41,7 +41,18 @@ __all__ = [
 NOT_PASSED = object()
 
 
-utc = timezone.utc
+def __getattr__(name):
+    if name != "utc":
+        raise AttributeError(f"module {__name__!r} has no attribute {name!r}")
+
+    warnings.warn(
+        "The django.utils.timezone.utc alias is deprecated. "
+        "Please update your code to use datetime.timezone.utc instead.",
+        RemovedInDjango50Warning,
+        stacklevel=2,
+    )
+
+    return timezone.utc
 
 
 def get_fixed_timezone(offset):
@@ -339,3 +350,11 @@ def _datetime_ambiguous_or_imaginary(dt, tz):
             return False
 
     return tz.utcoffset(dt.replace(fold=not dt.fold)) != tz.utcoffset(dt)
+
+
+# RemovedInDjango50Warning.
+_DIR = dir()
+
+
+def __dir__():
+    return sorted([*_DIR, "utc"])
diff --git a/docs/internals/deprecation.txt b/docs/internals/deprecation.txt
index 31eb732297..ab147725c1 100644
--- a/docs/internals/deprecation.txt
+++ b/docs/internals/deprecation.txt
@@ -94,6 +94,9 @@ details on these changes.
   ``django.contrib.auth.views.LogoutView`` and
   ``django.contrib.auth.views.logout_then_login()`` will be removed.
 
+* The ``django.utils.timezone.utc`` alias to ``datetime.timezone.utc`` will be
+  removed.
+
 .. _deprecation-removed-in-4.1:
 
 4.1
diff --git a/docs/ref/utils.txt b/docs/ref/utils.txt
index 8c12294cd6..a2be25f168 100644
--- a/docs/ref/utils.txt
+++ b/docs/ref/utils.txt
@@ -843,6 +843,11 @@ appropriate entities.
 
     :class:`~datetime.tzinfo` instance that represents UTC.
 
+    .. deprecated:: 4.1
+
+        This is an alias to :attr:`datetime.timezone.utc`. Use
+        :attr:`datetime.timezone.utc` directly.
+
 .. function:: get_fixed_timezone(offset)
 
     Returns a :class:`~datetime.tzinfo` instance that represents a time zone
diff --git a/docs/releases/4.1.txt b/docs/releases/4.1.txt
index eb4bde652b..8fc81e5ee7 100644
--- a/docs/releases/4.1.txt
+++ b/docs/releases/4.1.txt
@@ -545,6 +545,9 @@ Miscellaneous
   :meth:`.RemoteUserBackend.configure_user`. Support  for ``RemoteUserBackend``
   subclasses that do not accept this argument is deprecated.
 
+* The :data:`django.utils.timezone.utc` alias to :attr:`datetime.timezone.utc`
+  is deprecated. Use :attr:`datetime.timezone.utc` directly.
+
 Features removed in 4.1
 =======================
 
diff --git a/tests/migrations/test_writer.py b/tests/migrations/test_writer.py
index 3e95ca6c15..6ec6d938b9 100644
--- a/tests/migrations/test_writer.py
+++ b/tests/migrations/test_writer.py
@@ -29,10 +29,11 @@ from django.core.validators import EmailValidator, RegexValidator
 from django.db import migrations, models
 from django.db.migrations.serializer import BaseSerializer
 from django.db.migrations.writer import MigrationWriter, OperationWriter
-from django.test import SimpleTestCase
+from django.test import SimpleTestCase, ignore_warnings
 from django.utils.deconstruct import deconstructible
+from django.utils.deprecation import RemovedInDjango50Warning
 from django.utils.functional import SimpleLazyObject
-from django.utils.timezone import get_default_timezone, get_fixed_timezone, utc
+from django.utils.timezone import get_default_timezone, get_fixed_timezone
 from django.utils.translation import gettext_lazy as _
 
 from .models import FoodManager, FoodQuerySet
@@ -532,6 +533,8 @@ class WriterTests(SimpleTestCase):
             datetime.datetime(2014, 1, 1, 1, 1),
             ("datetime.datetime(2014, 1, 1, 1, 1)", {"import datetime"}),
         )
+        with ignore_warnings(category=RemovedInDjango50Warning):
+            from django.utils.timezone import utc
         for tzinfo in (utc, datetime.timezone.utc):
             with self.subTest(tzinfo=tzinfo):
                 self.assertSerializedResultEqual(
diff --git a/tests/timezones/tests.py b/tests/timezones/tests.py
index 4e26516041..f2617f4d0f 100644
--- a/tests/timezones/tests.py
+++ b/tests/timezones/tests.py
@@ -88,6 +88,19 @@ def get_timezones(key):
     return [constructor(key) for constructor in ZONE_CONSTRUCTORS]
 
 
+class UTCAliasTests(SimpleTestCase):
+    def test_alias_deprecation_warning(self):
+        msg = (
+            "The django.utils.timezone.utc alias is deprecated. "
+            "Please update your code to use datetime.timezone.utc instead."
+        )
+        with self.assertRaisesMessage(RemovedInDjango50Warning, msg):
+            timezone.utc
+
+    def test_timezone_module_dir_includes_utc(self):
+        self.assertIn("utc", dir(timezone))
+
+
 @contextmanager
 def override_database_connection_timezone(timezone):
     try: