#5471: fix expanduser() for $HOME set to "/".

Lib/posixpath.py

@@ -262,7 +262,7 @@ def expanduser(path):
         except KeyError:
             return path
         userhome = pwent.pw_dir
-    userhome = userhome.rstrip('/')
+    userhome = userhome.rstrip('/') or userhome
     return userhome + path[i:]
 
 

Lib/test/test_posixpath.py

@@ -345,6 +345,11 @@ class PosixPathTest(unittest.TestCase):
             self.assert_(isinstance(posixpath.expanduser("~root/"), basestring))
             self.assert_(isinstance(posixpath.expanduser("~foo/"), basestring))
 
+            orig_home = os.environ['HOME']
+            os.environ['HOME'] = '/'
+            self.assertEqual(posixpath.expanduser("~"), "/")
+            os.environ['HOME'] = orig_home
+
         self.assertRaises(TypeError, posixpath.expanduser)
 
     def test_expandvars(self):

Misc/NEWS

@@ -212,6 +212,8 @@ Core and Builtins
 Library
 -------
 
+- Issue 5471: Fix os.path.expanduser() for $HOME set to '/'.
+
 - Issue 1326077: fix the formatting of SyntaxErrors by the traceback module.
 
 - Issue 1726172: fix IndexError in the case of and empty response in ftplib.