1 files changed, 50 insertions, 0 deletions
diff --git a/Lib/test/test_importlib/extension/test_case_sensitivity.py b/Lib/test/test_importlib/extension/test_case_sensitivity.py
new file mode 100644
index 0000000000..76c53e4fd6
--- /dev/null
+++ b/Lib/test/test_importlib/extension/test_case_sensitivity.py
@@ -0,0 +1,50 @@
+import imp
+import sys
+from test import support
+import unittest
+from importlib import _bootstrap
+from .. import util
+from . import util as ext_util
+
+
+@util.case_insensitive_tests
+class ExtensionModuleCaseSensitivityTest(unittest.TestCase):
+
+    def find_module(self):
+        good_name = ext_util.NAME
+        bad_name = good_name.upper()
+        assert good_name != bad_name
+        finder = _bootstrap.FileFinder(ext_util.PATH,
+                                        (_bootstrap.ExtensionFileLoader,
+                                         _bootstrap.EXTENSION_SUFFIXES))
+        return finder.find_module(bad_name)
+
+    def test_case_sensitive(self):
+        with support.EnvironmentVarGuard() as env:
+            env.unset('PYTHONCASEOK')
+            if b'PYTHONCASEOK' in _bootstrap._os.environ:
+                self.skipTest('os.environ changes not reflected in '
+                              '_os.environ')
+            loader = self.find_module()
+            self.assertIsNone(loader)
+
+    def test_case_insensitivity(self):
+        with support.EnvironmentVarGuard() as env:
+            env.set('PYTHONCASEOK', '1')
+            if b'PYTHONCASEOK' not in _bootstrap._os.environ:
+                self.skipTest('os.environ changes not reflected in '
+                              '_os.environ')
+            loader = self.find_module()
+            self.assertTrue(hasattr(loader, 'load_module'))
+
+
+
+
+def test_main():
+    if ext_util.FILENAME is None:
+        return
+    support.run_unittest(ExtensionModuleCaseSensitivityTest)
+
+
+if __name__ == '__main__':
+    test_main()