Fix #11583. Changed os.path.isdir to use GetFileAttributes instead of os.stat.
By changing to the Windows GetFileAttributes API in nt._isdir we can figure
out if the path is a directory without opening the file via os.stat. This has
the minor benefit of speeding up os.path.isdir by at least 2x for regular
files and 10-15x improvements were seen on symbolic links (which opened the
file multiple times during os.stat). Since os.path.isdir is used in
several places on interpreter startup, we get a minor speedup in startup time.
diff --git a/Misc/NEWS b/Misc/NEWS
index 1995b14..6f10ba6 100644
--- a/Misc/NEWS
+++ b/Misc/NEWS
@@ -187,6 +187,9 @@
Library
-------
+- Issue #11583: Speed up os.path.isdir on Windows by using GetFileAttributes
+ instead of os.stat.
+
- Issue #12021: Make mmap's read() method argument optional. Patch by Petri
Lehtinen.