From 456e274578dc9863f42ab24d62adc0d8c511b50f Mon Sep 17 00:00:00 2001 From: Mariusz Felisiak Date: Fri, 26 Jan 2024 09:33:13 +0100 Subject: [PATCH] gh-112451: Prohibit subclassing of datetime.timezone. (#114190) This is consistent with C-extension datetime.timezone. --- Lib/_pydatetime.py | 3 +++ Lib/test/datetimetester.py | 4 ++++ .../Library/2024-01-24-20-11-46.gh-issue-112451.7YrG4p.rst | 2 ++ 3 files changed, 9 insertions(+) create mode 100644 Misc/NEWS.d/next/Library/2024-01-24-20-11-46.gh-issue-112451.7YrG4p.rst diff --git a/Lib/_pydatetime.py b/Lib/_pydatetime.py index bca2acf1fc88cf..355145387e355b 100644 --- a/Lib/_pydatetime.py +++ b/Lib/_pydatetime.py @@ -2347,6 +2347,9 @@ def __new__(cls, offset, name=_Omitted): "timedelta(hours=24).") return cls._create(offset, name) + def __init_subclass__(cls): + raise TypeError("type 'datetime.timezone' is not an acceptable base type") + @classmethod def _create(cls, offset, name=None): self = tzinfo.__new__(cls) diff --git a/Lib/test/datetimetester.py b/Lib/test/datetimetester.py index 8bda17358db87f..53ad5e57ada017 100644 --- a/Lib/test/datetimetester.py +++ b/Lib/test/datetimetester.py @@ -301,6 +301,10 @@ def test_inheritance(self): self.assertIsInstance(timezone.utc, tzinfo) self.assertIsInstance(self.EST, tzinfo) + def test_cannot_subclass(self): + with self.assertRaises(TypeError): + class MyTimezone(timezone): pass + def test_utcoffset(self): dummy = self.DT for h in [0, 1.5, 12]: diff --git a/Misc/NEWS.d/next/Library/2024-01-24-20-11-46.gh-issue-112451.7YrG4p.rst b/Misc/NEWS.d/next/Library/2024-01-24-20-11-46.gh-issue-112451.7YrG4p.rst new file mode 100644 index 00000000000000..126ca36a3b7cb1 --- /dev/null +++ b/Misc/NEWS.d/next/Library/2024-01-24-20-11-46.gh-issue-112451.7YrG4p.rst @@ -0,0 +1,2 @@ +Prohibit subclassing pure-Python :class:`datetime.timezone`. This is consistent +with C-extension implementation. Patch by Mariusz Felisiak.