bpo-40943: Fix skipitem() didn't raise SystemError (GH-25937)

`convertitem()` raises `SystemError` when 'GH-' is used without `PY_SSIZE_T_CLEAN`.
This commit makes `skipitem()` raise it too.
(cherry picked from commit 4ebf4a6bfad4afcbab3baf9c0159c7767e2a64c0)

Co-authored-by: Inada Naoki <songofacandy@gmail.com>

1 files changed, 20 insertions, 3 deletions

diff --git a/Modules/_testcapimodule.c b/Modules/_testcapimodule.c
index 0a3040f..d926ad8 100644
--- a/Modules/_testcapimodule.c
+++ b/Modules/_testcapimodule.c
@@ -5455,9 +5455,6 @@ pynumber_tobase(PyObject *module, PyObject *args)
 }
 
 
-static PyObject *test_buildvalue_issue38913(PyObject *, PyObject *);
-
-
 static PyObject*
 test_set_type_size(PyObject *self, PyObject *Py_UNUSED(ignored))
 {
@@ -5596,6 +5593,8 @@ test_fatal_error(PyObject *self, PyObject *args)
 }
 
 
+static PyObject *test_buildvalue_issue38913(PyObject *, PyObject *);
+static PyObject *getargs_s_hash_int(PyObject *, PyObject *, PyObject*);
 
 static PyMethodDef TestMethods[] = {
     {"raise_exception",         raise_exception,                 METH_VARARGS},
@@ -5703,6 +5702,8 @@ static PyMethodDef TestMethods[] = {
     {"getargs_s",               getargs_s,                       METH_VARARGS},
     {"getargs_s_star",          getargs_s_star,                  METH_VARARGS},
     {"getargs_s_hash",          getargs_s_hash,                  METH_VARARGS},
+    {"getargs_s_hash_int",      (PyCFunction)(void(*)(void))getargs_s_hash_int,
+      METH_VARARGS|METH_KEYWORDS},
     {"getargs_z",               getargs_z,                       METH_VARARGS},
     {"getargs_z_star",          getargs_z_star,                  METH_VARARGS},
     {"getargs_z_hash",          getargs_z_hash,                  METH_VARARGS},
@@ -7375,3 +7376,19 @@ test_buildvalue_issue38913(PyObject *self, PyObject *Py_UNUSED(ignored))
 
     Py_RETURN_NONE;
 }
+
+#undef PyArg_ParseTupleAndKeywords
+PyAPI_FUNC(int) PyArg_ParseTupleAndKeywords(PyObject *, PyObject *,
+                                            const char *, char **, ...);
+
+static PyObject *
+getargs_s_hash_int(PyObject *self, PyObject *args, PyObject *kwargs)
+{
+    static char *keywords[] = {"", "x", NULL};
+    const char *s;
+    int len;
+    int i = 0;
+    if (!PyArg_ParseTupleAndKeywords(args, kwargs, "|s#i", keywords, &s, &len, &i))
+        return NULL;
+    Py_RETURN_NONE;
+}