[Python-checkins] bpo-45629: Improve test.support.skip_if_buildbot (GH-31094)

[gpshead]

https://github.com/python/cpython/commit/8726067ace98a27557e9fdf1a8e1c509c37cfcfc
commit: 8726067ace98a27557e9fdf1a8e1c509c37cfcfc
branch: main
author: Gregory P. Smith <greg at krypto.org>
committer: gpshead <greg at krypto.org>
date: 2022-02-02T21:36:16-08:00
summary:

bpo-45629: Improve test.support.skip_if_buildbot (GH-31094)

It was added as part of #29222 to avoid running freeze tool tests on the
buildbots but the logic was wrong so it did not skip tests on typical posix
setup buildbots where the worker is launched from cron via an @reboot task and
thus have no USER environment variable.  This uses the canonical
`getpass.getuser()` API rather than rolling its own attempt.

files:
M Lib/test/support/__init__.py

diff --git a/Lib/test/support/__init__.py b/Lib/test/support/__init__.py
index d71cfe5ee44fd..e5eb66e9068e7 100644
--- a/Lib/test/support/__init__.py
+++ b/Lib/test/support/__init__.py
@@ -5,6 +5,7 @@
 
 import contextlib
 import functools
+import getpass
 import os
 import re
 import stat
@@ -378,10 +379,11 @@ def skip_if_buildbot(reason=None):
     """Decorator raising SkipTest if running on a buildbot."""
     if not reason:
         reason = 'not suitable for buildbots'
-    if sys.platform == 'win32':
-        isbuildbot = os.environ.get('USERNAME') == 'Buildbot'
-    else:
-        isbuildbot = os.environ.get('USER') == 'buildbot'
+    try:
+        isbuildbot = getpass.getuser().lower() == 'buildbot'
+    except (KeyError, EnvironmentError) as err:
+        warnings.warn(f'getpass.getuser() failed {err}.', RuntimeWarning)
+        isbuildbot = False
     return unittest.skipIf(isbuildbot, reason)
 
 def check_sanitizer(*, address=False, memory=False, ub=False):