From cee9efc0ab3068e05a853ffb27c82ada869372fe Mon Sep 17 00:00:00 2001
From: Adam Turner <9087854+aa-turner@users.noreply.github.com>
Date: Tue, 30 Jul 2024 01:51:27 +0100
Subject: [PATCH] Use ``classmethod`` for a class method

---
 CHANGES.rst                | 2 ++
 sphinx/highlighting.py     | 2 +-
 tests/test_highlighting.py | 2 +-
 3 files changed, 4 insertions(+), 2 deletions(-)

diff --git a/CHANGES.rst b/CHANGES.rst
index b94c08f089e..0f39c01cbd7 100644
--- a/CHANGES.rst
+++ b/CHANGES.rst
@@ -4,6 +4,8 @@ Release 8.0.2 (in development)
 Bugs fixed
 ----------
 
+* Fix the ``pygments.Formatter.__class_getitem__`` patch.
+  Patch by Adam Turner.
 
 Release 8.0.1 (released Jul 30, 2024)
 =====================================
diff --git a/sphinx/highlighting.py b/sphinx/highlighting.py
index bb2687a2bc8..86bdd234430 100644
--- a/sphinx/highlighting.py
+++ b/sphinx/highlighting.py
@@ -34,7 +34,7 @@
 if tuple(map(int, pygments.__version__.split('.')))[:2] < (2, 18):
     from pygments.formatter import Formatter  # NoQA: F811
 
-    Formatter.__class_getitem__ = lambda cls, name: cls  # type: ignore[attr-defined]
+    Formatter.__class_getitem__ = classmethod(lambda cls, name: cls)  # type: ignore[attr-defined]
 
 logger = logging.getLogger(__name__)
 
diff --git a/tests/test_highlighting.py b/tests/test_highlighting.py
index 1b8c2fbff73..95d0b4513a8 100644
--- a/tests/test_highlighting.py
+++ b/tests/test_highlighting.py
@@ -11,7 +11,7 @@
 
 if tuple(map(int, pygments.__version__.split('.')))[:2] < (2, 18):
     from pygments.formatter import Formatter
-    Formatter.__class_getitem__ = lambda cls, name: cls  # type: ignore[attr-defined]
+    Formatter.__class_getitem__ = classmethod(lambda cls, name: cls)  # type: ignore[attr-defined]
 
 
 class MyLexer(RegexLexer):