bpo-35306: Avoid raising OSError from pathlib.Path.exists when passed an invalid filename (GH-25529)

(cherry picked from commit 4696f12) Co-authored-by: Steve Dower <steve.dower@python.org>

Author: miss-islington

Lib/pathlib.py

@@ -39,6 +39,7 @@
 
 _IGNORED_WINERRORS = (
  21, # ERROR_NOT_READY - drive exists but is not accessible
+ 123, # ERROR_INVALID_NAME - fix for bpo-35306
  1921, # ERROR_CANT_RESOLVE_FILENAME - fix for broken symlink pointing to itself
 )
 

Misc/NEWS.d/next/Windows/2021-04-22-20-39-49.bpo-35306.F0Cg6X.rst

@@ -0,0 +1,2 @@
+Avoid raising errors from :meth:`pathlib.Path.exists()` when passed an
+invalid filename.