Issue #5692: In :class:`zipfile.Zipfile`, fix wrong path calculation when extracting a file to the root directory.

Lib/zipfile.py

@@ -952,7 +952,9 @@ class ZipFile:
         """
         # build the destination pathname, replacing
         # forward slashes to platform specific separators.
-        if targetpath[-1:] in (os.path.sep, os.path.altsep):
+        # Strip trailing path separator, unless it represents the root.
+        if (targetpath[-1:] in (os.path.sep, os.path.altsep)
+            and len(os.path.splitdrive(targetpath)[1]) > 1):
             targetpath = targetpath[:-1]
 
         # don't include leading "/" from file name if present

Misc/NEWS

@@ -269,6 +269,9 @@ Core and Builtins
 Library
 -------
 
+- Issue #5692: In :class:`zipfile.Zipfile`, fix wrong path calculation when
+  extracting a file to the root directory.
+
 - Issue #5913: os.listdir() should fail for empty path on windows.
 
 - Issue #5084: unpickling now interns the attribute names of pickled objects,