Issue #23934: Fix inspect.signature to fail correctly for builtin types.

Initial patch by James Powell.

1 files changed, 6 insertions, 1 deletions

diff --git a/Lib/test/test_inspect.py b/Lib/test/test_inspect.py
index 9f09b83..4695da8 100644
--- a/Lib/test/test_inspect.py
+++ b/Lib/test/test_inspect.py
@@ -1980,9 +1980,14 @@ class TestSignatureObject(unittest.TestCase):
     @cpython_only
     def test_signature_on_builtins_no_signature(self):
         import _testcapi
-        with self.assertRaisesRegex(ValueError, 'no signature found for builtin'):
+        with self.assertRaisesRegex(ValueError,
+                                    'no signature found for builtin'):
             inspect.signature(_testcapi.docstring_no_signature)
 
+        with self.assertRaisesRegex(ValueError,
+                                    'no signature found for builtin'):
+            inspect.signature(str)
+
     def test_signature_on_non_function(self):
         with self.assertRaisesRegex(TypeError, 'is not a callable object'):
             inspect.signature(42)