gh-129033: Remove _PyInterpreterState_SetConfig() function

Include/internal/pycore_interp.h

@@ -341,43 +341,6 @@ extern void _PyInterpreterState_SetWhence(
 
 extern const PyConfig* _PyInterpreterState_GetConfig(PyInterpreterState *interp);
 
-// Get a copy of the current interpreter configuration.
-//
-// Return 0 on success. Raise an exception and return -1 on error.
-//
-// The caller must initialize 'config', using PyConfig_InitPythonConfig()
-// for example.
-//
-// Python must be preinitialized to call this method.
-// The caller must hold the GIL.
-//
-// Once done with the configuration, PyConfig_Clear() must be called to clear
-// it.
-//
-// Export for '_testinternalcapi' shared extension.
-PyAPI_FUNC(int) _PyInterpreterState_GetConfigCopy(
-    struct PyConfig *config);
-
-// Set the configuration of the current interpreter.
-//
-// This function should be called during or just after the Python
-// initialization.
-//
-// Update the sys module with the new configuration. If the sys module was
-// modified directly after the Python initialization, these changes are lost.
-//
-// Some configuration like faulthandler or warnoptions can be updated in the
-// configuration, but don't reconfigure Python (don't enable/disable
-// faulthandler and don't reconfigure warnings filters).
-//
-// Return 0 on success. Raise an exception and return -1 on error.
-//
-// The configuration should come from _PyInterpreterState_GetConfigCopy().
-//
-// Export for '_testinternalcapi' shared extension.
-PyAPI_FUNC(int) _PyInterpreterState_SetConfig(
-    const struct PyConfig *config);
-
 
 /*
 Runtime Feature Flags

Lib/test/support/__init__.py

@@ -505,10 +505,10 @@ def requires_lzma(reason='requires lzma'):
 
 def has_no_debug_ranges():
     try:
-        import _testinternalcapi
+        import _testcapi
     except ImportError:
         raise unittest.SkipTest("_testinternalcapi required")
-    config = _testinternalcapi.get_config()
+    return not _testcapi.config_get('code_debug_ranges')
     return not bool(config['code_debug_ranges'])
 
 def requires_debug_ranges(reason='requires co_positions / debug_ranges'):

Lib/test/test_capi/test_misc.py

@@ -2141,28 +2141,27 @@ async def foo(arg): return await arg  # Py 3.5
             self.assertEqual(ret, 0)
             self.assertEqual(pickle.load(f), {'a': '123x', 'b': '123'})
 
+    # _testcapi cannot be imported in a subinterpreter on a Free Threaded build
+    @support.requires_gil_enabled()
     def test_py_config_isoloated_per_interpreter(self):
         # A config change in one interpreter must not leak to out to others.
         #
         # This test could verify ANY config value, it just happens to have been
         # written around the time of int_max_str_digits. Refactoring is okay.
         code = """if 1:
-        import sys, _testinternalcapi
+        import sys, _testcapi
 
         # Any config value would do, this happens to be the one being
         # double checked at the time this test was written.
-        config = _testinternalcapi.get_config()
-        config['int_max_str_digits'] = 55555
-        config['parse_argv'] = 0
-        _testinternalcapi.set_config(config)
-        sub_value = _testinternalcapi.get_config()['int_max_str_digits']
+        _testcapi.config_set('int_max_str_digits', 55555)
+        sub_value = _testcapi.config_get('int_max_str_digits')
         assert sub_value == 55555, sub_value
         """
-        before_config = _testinternalcapi.get_config()
-        assert before_config['int_max_str_digits'] != 55555
+        before_config = _testcapi.config_get('int_max_str_digits')
+        assert before_config != 55555
         self.assertEqual(support.run_in_subinterp(code), 0,
                          'subinterp code failure, check stderr.')
-        after_config = _testinternalcapi.get_config()
+        after_config = _testcapi.config_get('int_max_str_digits')
         self.assertIsNot(
                 before_config, after_config,
                 "Expected get_config() to return a new dict on each call")