gh-106307: C API: Add PyMapping_GetOptionalItem() function (GH-106308)

Also add PyMapping_GetOptionalItemString() function.

1 files changed, 6 insertions, 9 deletions

diff --git a/Modules/_pickle.c b/Modules/_pickle.c
index a68a0aa..5ecf7ca 100644
--- a/Modules/_pickle.c
+++ b/Modules/_pickle.c
@@ -4438,16 +4438,13 @@ save(PickleState *st, PicklerObject *self, PyObject *obj, int pers_save)
                PyObject_GetItem and _PyObject_GetAttrId used below. */
             Py_INCREF(reduce_func);
         }
-    } else {
-        reduce_func = PyObject_GetItem(self->dispatch_table,
-                                       (PyObject *)type);
-        if (reduce_func == NULL) {
-            if (PyErr_ExceptionMatches(PyExc_KeyError))
-                PyErr_Clear();
-            else
-                goto error;
-        }
     }
+    else if (PyMapping_GetOptionalItem(self->dispatch_table, (PyObject *)type,
+                                       &reduce_func) < 0)
+    {
+        goto error;
+    }
+
     if (reduce_func != NULL) {
         reduce_value = _Pickle_FastCall(reduce_func, Py_NewRef(obj));
     }