Issue #25583: Avoid incorrect errors raised by os.makedirs(exist_ok=True)
diff --git a/Lib/os.py b/Lib/os.py
index a8f6a0b..27b241a 100644
--- a/Lib/os.py
+++ b/Lib/os.py
@@ -226,7 +226,7 @@
try:
makedirs(head, mode, exist_ok)
except FileExistsError:
- # be happy if someone already created the path
+ # Defeats race condition when another thread created the path
pass
cdir = curdir
if isinstance(tail, bytes):
@@ -235,8 +235,10 @@
return
try:
mkdir(name, mode)
- except OSError as e:
- if not exist_ok or e.errno != errno.EEXIST or not path.isdir(name):
+ except OSError:
+ # Cannot rely on checking for EEXIST, since the operating system
+ # could give priority to other errors like EACCES or EROFS
+ if not exist_ok or not path.isdir(name):
raise
def removedirs(name):
diff --git a/Lib/test/test_os.py b/Lib/test/test_os.py
index 1f7e49c..e29b0d5 100644
--- a/Lib/test/test_os.py
+++ b/Lib/test/test_os.py
@@ -971,6 +971,9 @@
os.makedirs(path, mode=mode, exist_ok=True)
os.umask(old_mask)
+ # Issue #25583: A drive root could raise PermissionError on Windows
+ os.makedirs(os.path.abspath('/'), exist_ok=True)
+
@unittest.skipUnless(hasattr(os, 'chown'), 'test needs os.chown')
def test_chown_uid_gid_arguments_must_be_index(self):
stat = os.stat(support.TESTFN)