[Python-checkins] bpo-36160: Fix test_site so that it can run independently of other tests (GH-12131) (GH-26262)

[iritkatriel]

https://github.com/python/cpython/commit/4389711ce935bef3844dd24d7fe8460a5fef62e6
commit: 4389711ce935bef3844dd24d7fe8460a5fef62e6
branch: 3.10
author: Miss Islington (bot) <31488909+miss-islington at users.noreply.github.com>
committer: iritkatriel <iritkatriel at yahoo.com>
date: 2021-05-20T11:42:00+01:00
summary:

bpo-36160: Fix test_site so that it can run independently of other tests (GH-12131) (GH-26262)

(cherry picked from commit 1270ad6ec8fe1f71e7d88086474f96f99670ac3a)

Co-authored-by: native-api <vano at mail.mipt.ru>

files:
M Lib/test/test_site.py

diff --git a/Lib/test/test_site.py b/Lib/test/test_site.py
index 9b4ab42a727b4..fa74e7770ede2 100644
--- a/Lib/test/test_site.py
+++ b/Lib/test/test_site.py
@@ -79,8 +79,10 @@ def tearDown(self):
         site.USER_SITE = self.old_site
         site.PREFIXES = self.old_prefixes
         sysconfig._CONFIG_VARS = self.original_vars
-        sysconfig._CONFIG_VARS.clear()
-        sysconfig._CONFIG_VARS.update(self.old_vars)
+        # _CONFIG_VARS is None before get_config_vars() is called
+        if sysconfig._CONFIG_VARS is not None:
+            sysconfig._CONFIG_VARS.clear()
+            sysconfig._CONFIG_VARS.update(self.old_vars)
 
     def test_makepath(self):
         # Test makepath() have an absolute path for its first return value