commit 595b516965ee88b817dc1b3d7713e1f3f263634d
author Miss Islington (bot) <31488909+miss-islington@users.noreply.github.com> Tue Jan 28 01:59:43 2020 -0800
committer GitHub <noreply@github.com> Tue Jan 28 01:59:43 2020 -0800
tree fd9f482a0fd5a39057bec69349325c089520b43c
parent 41f4dc3bcf30cb8362a062a26818311c704ea89f

bpo-38883: Don't use POSIX `$HOME` in `pathlib.Path.home/expanduser` on Windows (GH-17961)


In bpo-36264 os.path.expanduser was changed to ignore HOME on Windows.

Path.expanduser/home still honored HOME despite being documented as behaving the same
as os.path.expanduser. This makes them also ignore HOME so that both implementations
behave the same way again.
(cherry picked from commit c45a2aa9e255b5c7c211faa79f6b23895b64ab27)

Co-authored-by: Christoph Reiter <reiter.christoph@gmail.com>

Lib/pathlib.py

diff --git a/Lib/pathlib.py b/Lib/pathlib.py
index 8ed3c88..015370a 100644
--- a/Lib/pathlib.py
+++ b/Lib/pathlib.py
@@ -253,9 +253,7 @@
             return 'file:' + urlquote_from_bytes(path.as_posix().encode('utf-8'))
 
     def gethomedir(self, username):
-        if 'HOME' in os.environ:
-            userhome = os.environ['HOME']
-        elif 'USERPROFILE' in os.environ:
+        if 'USERPROFILE' in os.environ:
             userhome = os.environ['USERPROFILE']
         elif 'HOMEPATH' in os.environ:
             try:

Lib/test/test_pathlib.py

diff --git a/Lib/test/test_pathlib.py b/Lib/test/test_pathlib.py
index b127343..97fc5d8 100644
--- a/Lib/test/test_pathlib.py
+++ b/Lib/test/test_pathlib.py
@@ -1296,8 +1296,16 @@
         self.assertTrue(p.is_absolute())
 
     def test_home(self):
-        p = self.cls.home()
-        self._test_home(p)
+        with support.EnvironmentVarGuard() as env:
+            self._test_home(self.cls.home())
+
+            env.clear()
+            env['USERPROFILE'] = os.path.join(BASE, 'userprofile')
+            self._test_home(self.cls.home())
+
+            # bpo-38883: ignore `HOME` when set on windows
+            env['HOME'] = os.path.join(BASE, 'home')
+            self._test_home(self.cls.home())
 
     def test_samefile(self):
         fileA_path = os.path.join(BASE, 'fileA')
@@ -2348,12 +2356,6 @@
                 self.assertEqual(p5.expanduser(), p5)
                 self.assertEqual(p6.expanduser(), p6)
 
-            # Test the first lookup key in the env vars.
-            env['HOME'] = 'C:\\Users\\alice'
-            check()
-
-            # Test that HOMEPATH is available instead.
-            env.pop('HOME', None)
             env['HOMEPATH'] = 'C:\\Users\\alice'
             check()
 
@@ -2366,6 +2368,10 @@
             env['USERPROFILE'] = 'C:\\Users\\alice'
             check()
 
+            # bpo-38883: ignore `HOME` when set on windows
+            env['HOME'] = 'C:\\Users\\eve'
+            check()
+
 
 class CompatiblePathTest(unittest.TestCase):
     """