--- a/tests/common.py	Wed Mar 09 15:08:11 2022 +0100
+++ b/tests/common.py	Wed Mar 08 17:04:58 2023 +0100
@@ -14,6 +14,22 @@
 
 class basetest(unittest.TestCase):
     def setUp(self):
+        os.environ['LANG'] = os.environ['LC_ALL'] = os.environ['LANGUAGE'] = 'C'
+        os.environ["EMAIL"] = "Foo Bar <foo.bar@example.com>"
+        os.environ['CDPATH'] = ''
+        os.environ['COLUMNS'] = '80'
+        os.environ['GREP_OPTIONS'] = ''
+        os.environ['http_proxy'] = ''
+
+        os.environ["HGEDITOR"] = sys.executable + ' -c "import sys; sys.exit(0)"'
+        os.environ["HGMERGE"] = "internal:merge"
+        os.environ["HGUSER"]   = "test"
+        os.environ["HGENCODING"] = "ascii"
+        os.environ["HGENCODINGMODE"] = "strict"
+        tmpdir = tempfile.mkdtemp('', 'python-hglib.')
+        os.environ["HGTMP"] = os.path.realpath(tmpdir)
+        os.environ["HGRCPATH"] = os.pathsep
+
         self._testtmp = os.environ["TESTTMP"] = os.environ["HOME"] = \
             os.path.join(os.environ["HGTMP"], self.__class__.__name__)
 
@@ -37,8 +53,9 @@
             if client.server is not None:
                 client.close()
         os.chdir('..')
+
         try:
-            shutil.rmtree(self._testtmp)
+            shutil.rmtree(self._testtmp, ignore_errors=True)
         except AttributeError:
             pass # if our setUp was overriden