gh-105873: Make _xxsubinterpreters use exception type name in shared exception (#105874)

Author: chgnrdv

Lib/test/test__xxsubinterpreters.py

@@ -731,10 +731,10 @@ def assert_run_failed(self, exctype, msg=None):
             yield
         if msg is None:
             self.assertEqual(str(caught.exception).split(':')[0],
-                             str(exctype))
+                             exctype.__name__)
         else:
             self.assertEqual(str(caught.exception),
-                             "{}: {}".format(exctype, msg))
+                             "{}: {}".format(exctype.__name__, msg))
 
     def test_invalid_syntax(self):
         with self.assert_run_failed(SyntaxError):

Lib/test/test_importlib/test_util.py

@@ -655,7 +655,7 @@ def test_magic_number(self):
 @unittest.skipIf(_interpreters is None, 'subinterpreters required')
 class IncompatibleExtensionModuleRestrictionsTests(unittest.TestCase):
 
-    ERROR = re.compile("^<class 'ImportError'>: module (.*) does not support loading in subinterpreters")
+    ERROR = re.compile("^ImportError: module (.*) does not support loading in subinterpreters")
 
     def run_with_own_gil(self, script):
         interpid = _interpreters.create(isolated=True)

Modules/_xxsubinterpretersmodule.c

@@ -273,7 +273,7 @@ _sharedexception_bind(PyObject *exc, _sharedexception *sharedexc)
     assert(exc != NULL);
     const char *failure = NULL;
 
-    PyObject *nameobj = PyUnicode_FromFormat("%S", Py_TYPE(exc));
+    PyObject *nameobj = PyUnicode_FromString(Py_TYPE(exc)->tp_name);
     if (nameobj == NULL) {
         failure = "unable to format exception type name";
         goto error;