[3.12] gh-112155: Run typing.py doctests during tests (GH-112156) (#112230)

Author: sobolevn

Lib/test/test_typing.py

@@ -9282,5 +9282,11 @@ def test_is_not_instance_of_iterable(self):
             self.assertNotIsInstance(type_to_test, collections.abc.Iterable)
 
 
+def load_tests(loader, tests, pattern):
+    import doctest
+    tests.addTests(doctest.DocTestSuite(typing))
+    return tests
+
+
 if __name__ == '__main__':
     main()