gh-129027: Raise DeprecationWarning for sys._clear_type_cache (#129043)

Co-authored-by: Bénédikt Tran <10796600+picnixz@users.noreply.github.com>
Co-authored-by: Hugo van Kemenade <1324225+hugovk@users.noreply.github.com>

1 files changed, 8 insertions, 0 deletions

diff --git a/Python/sysmodule.c b/Python/sysmodule.c
index 3e0165acd6f..1a7b01bf97f 100644
--- a/Python/sysmodule.c
+++ b/Python/sysmodule.c
@@ -2208,6 +2208,14 @@ static PyObject *
 sys__clear_type_cache_impl(PyObject *module)
 /*[clinic end generated code: output=20e48ca54a6f6971 input=127f3e04a8d9b555]*/
 {
+    if (PyErr_WarnEx(PyExc_DeprecationWarning,
+                     "sys._clear_type_cache() is deprecated and"
+                     " scheduled for removal in a future version."
+                     " Use sys._clear_internal_caches() instead.",
+                     1) < 0)
+    {
+        return NULL;
+    }
     PyType_ClearCache();
     Py_RETURN_NONE;
 }