From: Miss Islington (bot) <31488909+miss-islington@users.noreply.github.com>
Date: Thu, 20 Feb 2025 11:52:06 +0000 (+0100)
Subject: [3.13] gh-130250: use support.swap_attr() in test and don't assume we're beginning... 
X-Git-Tag: v3.13.3~244
X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=d103357785e239edd1a3b0881fff3d6682a7bfc2;p=thirdparty%2FPython%2Fcpython.git

[3.13] gh-130250: use support.swap_attr() in test and don't assume we're beginning with a clean system state (GH-130342) (#130344)

gh-130250: use support.swap_attr() in test and don't assume we're beginning with a clean system state (GH-130342)
(cherry picked from commit 048ee2d5ec761296ef67f5c59aee1f24408b12db)

Co-authored-by: Irit Katriel <1055913+iritkatriel@users.noreply.github.com>
---

diff --git a/Lib/test/test_traceback.py b/Lib/test/test_traceback.py
index 321ee2294b9f..d104402f2fd6 100644
--- a/Lib/test/test_traceback.py
+++ b/Lib/test/test_traceback.py
@@ -517,14 +517,10 @@ class TracebackCases(unittest.TestCase):
         self.assertEqual(output.getvalue(), "Exception: projector\n")
 
     def test_print_last(self):
-        self.assertIsNone(getattr(sys, "last_exc", None))
-        try:
-            sys.last_exc = ValueError(42)
+        with support.swap_attr(sys, 'last_exc', ValueError(42)):
             output = StringIO()
             traceback.print_last(file=output)
             self.assertEqual(output.getvalue(), "ValueError: 42\n")
-        finally:
-            sys.last_exc = None
 
     def test_format_exception_exc(self):
         e = Exception("projector")