From f73a97aba7f6a586bf96ad970294a332109ab558 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Zbigniew=20J=C4=99drzejewski-Szmek?= Date: Sun, 24 Apr 2022 12:54:57 +0200 Subject: [PATCH] py3.11: fix Enum formatting to work with python3.11-a7 Something strange is happening with .__repr__() access in python3.11: >>> mkosi.backend.ManifestFormat.mro() [, , , ] >>> mkosi.backend.ManifestFormat.changelog.__repr__() Traceback (most recent call last): File "", line 1, in File "/usr/lib64/python3.11/enum.py", line 1194, in __repr__ return "<%s.%s: %s>" % (self.__class__.__name__, self._name_, v_repr(self._value_)) ^^^^^^^^^^^^^^^^^^^^ File "/home/zbyszek/src/mkosi/mkosi/backend.py", line 95, in __repr__ return cast(str, getattr(self, "name")) ^^^^^^^^^^^^^^^^^^^^^ AttributeError: 'str' object has no attribute 'name' Enum somehow subverts normal lookup and makes its own __repr__ function be used, even though Parseable is listed first in MRO. This seems to be related to PEP 663, which was rejected, and the changes reverted for -a4 [1], but then the revert was reverted [2]. Let's just sidestep MRO with a method redefinition: >>> mkosi.backend.ManifestFormat.changelog.__repr__ >>> mkosi.backend.ManifestFormat.changelog.__repr__() 'changelog' This should work on all python versions. If python3.11 returns to previous semantics before the final release, we can remove the workaround. [1] commit acf7403f9baea3ae1119fc6b4a3298522188bf96 Author: Ethan Furman Date: Sat Jan 15 22:41:43 2022 -0800 bpo-40066: [Enum] update str() and format() output (GH-30582) Undo rejected PEP-663 changes: - restore `repr()` to its 3.10 status - restore `str()` to its 3.10 status [2] commit 42a64c03ec5c443f2a5c2ee4284622f5d1f5326c Author: Victor Stinner Date: Mon Jan 17 13:58:40 2022 +0100 Revert "bpo-40066: [Enum] update str() and format() output (GH-30582)" (GH-30632) This reverts commit acf7403f9baea3ae1119fc6b4a3298522188bf96. --- mkosi/backend.py | 8 ++++++++ 1 file changed, 8 insertions(+) diff --git a/mkosi/backend.py b/mkosi/backend.py index 78006f392a..3c57ec6295 100644 --- a/mkosi/backend.py +++ b/mkosi/backend.py @@ -217,11 +217,19 @@ class OutputFormat(Parseable, enum.Enum): def has_fs_compression(self) -> bool: return self.is_squashfs() or self.is_btrfs() + def __repr__(self) -> str: + return Parseable.__repr__(self) + def __str__(self) -> str: + return Parseable.__str__(self) class ManifestFormat(Parseable, enum.Enum): json = "json" # the standard manifest in json format changelog = "changelog" # human-readable text file with package changelogs + def __repr__(self) -> str: + return Parseable.__repr__(self) + def __str__(self) -> str: + return Parseable.__str__(self) class PartitionIdentifier(enum.Enum): esp = 'esp'