@jaraco I also took the time to investigate the GitHub pull request's "Files changed" page, where I noticed that the HTML included the invisible character, although it wasn't explicitly displayed.

I believe it would be beneficial to suggest a feature to the GitHub development team to improve the visibility of invisible characters in code difference pages, making it easier for developers to identify and address these issues.

Update:
Ooh, in fact, there's already a long-standing feature request to GitHub, dating back to 2022, highlighting the need for this capability: https://github.com/orgs/community/discussions/10966

Thanks @xyb. I was planning to let the fix in zipp to make its way here naturally, but I'm also happy to have this fixed here sooner.

Since cpython uses ruff for linting

I don't think it's the case that CPython uses ruff for linting. in fact, I don't think any linters are used. It's only the case that zipp uses ruff for linting and the code is subsequently merged into CPython.

FYI, we can show the invisible characters in the git commit history using cat -A:

$ git show 572b48f7f2dd8ef795417f08f2cd70b2140e3446 | cat -A

diff --git a/Lib/zipfile/_path/__init__.py b/Lib/zipfile/_path/__init__.py$
index 5079db90648..c0e53e273cf 100644$
--- a/Lib/zipfile/_path/__init__.py$
+++ b/Lib/zipfile/_path/__init__.py$
@@ -280,7 +280,7 @@ class Path:$
     >>> str(path.parent)$
     'mem'$
 $
-    If the zipfile has no filename, such M-oM-;M-?attributes are not$
+    If the zipfile has no filename, such attributes are not$
     valid and accessing them will raise an Exception.$
 $
     >>> zf.filename = None$

I don't think it's the case that CPython uses ruff for linting. in fact, I don't think any linters are used.

We use some specific Ruff rules on some specific areas of the CPython codebase. But we do not currently run Ruff on any parts of the standard library (and I think it would have to be extensively discussed before we did so). See https://github.com/python/cpython/blob/main/.pre-commit-config.yaml for details.