1 files changed, 9 insertions, 0 deletions
diff --git a/Lib/test/test_importlib/util.py b/Lib/test/test_importlib/util.py
index ce20377..43896c5 100644
--- a/Lib/test/test_importlib/util.py
+++ b/Lib/test/test_importlib/util.py
@@ -378,3 +378,12 @@ def mock_path_hook(*entries, importer):
             raise ImportError
         return importer
     return hook
+
+
+class CASEOKTestBase:
+
+    def caseok_env_changed(self, *, should_exist):
+        possibilities = b'PYTHONCASEOK', 'PYTHONCASEOK'
+        if any(x in self.importlib._bootstrap_external._os.environ
+                    for x in possibilities) != should_exist:
+            self.skipTest('os.environ changes not reflected in _os.environ')