From 9775398f630842a3a143f622be3bc45b9f2fb268 Mon Sep 17 00:00:00 2001
From: Fabian Henze <32638720+henzef@users.noreply.github.com>
Date: Thu, 21 Sep 2023 13:16:44 +0200
Subject: [PATCH] B902: Add exceptions for standard library metaclasses

I faced a false positive when deriving my metaclass from ABCMeta, which should be fixed with this commit. I also added EnumMeta to this list, because it was the only other public metaclass in the standard library.
---
 bugbear.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/bugbear.py b/bugbear.py
index 5fbfa19..e296f55 100644
--- a/bugbear.py
+++ b/bugbear.py
@@ -1028,7 +1028,7 @@ def is_classmethod(decorators: Set[str]) -> bool:
             return
 
         bases = {b.id for b in cls.bases if isinstance(b, ast.Name)}
-        if "type" in bases:
+        if any(basetype in bases for basetype in ("type", "ABCMeta", "EnumMeta")):
             if is_classmethod(decorators):
                 expected_first_args = B902.metacls
                 kind = "metaclass class"