1 files changed, 14 insertions, 4 deletions
diff --git a/Lib/test/test_tuple.py b/Lib/test/test_tuple.py
index 51875a1cbd..fb113ab29a 100644
--- a/Lib/test/test_tuple.py
+++ b/Lib/test/test_tuple.py
@@ -6,6 +6,11 @@ import pickle
 class TupleTest(seq_tests.CommonTest):
     type2test = tuple
 
+    def test_getitem_error(self):
+        msg = "tuple indices must be integers or slices"
+        with self.assertRaisesRegex(TypeError, msg):
+            ()['a']
+
     def test_constructors(self):
         super().test_constructors()
         # calling built-in types without argument must return empty
@@ -203,8 +208,13 @@ class TupleTest(seq_tests.CommonTest):
         with self.assertRaises(TypeError):
             [3,] + T((1,2))
 
-def test_main():
-    support.run_unittest(TupleTest)
+    def test_lexicographic_ordering(self):
+        # Issue 21100
+        a = self.type2test([1, 2])
+        b = self.type2test([1, 2, 0])
+        c = self.type2test([1, 3])
+        self.assertLess(a, b)
+        self.assertLess(b, c)
 
-if __name__=="__main__":
-    test_main()
+if __name__ == "__main__":
+    unittest.main()