Fix PyTruffleTuple_SET_ITEM was not stealing

Author: msimacek

graalpython/com.oracle.graal.python.test/src/tests/cpyext/test_method.py

@@ -65,8 +65,10 @@ def test_methods(self):
                 PyObject *argTuple = PyTuple_New(nargs);
                 if (!argTuple)
                     return NULL;
-                for (int i = 0; i < nargs; i++)
+                for (int i = 0; i < nargs; i++) {
+                    Py_INCREF(args[i]);
                     PyTuple_SET_ITEM(argTuple, i, args[i]);
+                }
                 return argTuple;
             }
             static PyObject* keywordsToDict(PyObject *const *args, Py_ssize_t nargs, PyObject *kwnames) {

graalpython/com.oracle.graal.python.test/src/tests/cpyext/test_tuple.py

@@ -166,6 +166,7 @@ class TestPyTuple(CPyExtTestCase):
                     Py_DECREF(tuple);
                     return NULL;
                 }
+                Py_INCREF(item);
                 PyTuple_SET_ITEM(tuple, i, item);
             }
             Py_INCREF(value);

graalpython/com.oracle.graal.python/src/com/oracle/graal/python/builtins/modules/cext/PythonCextTupleBuiltins.java

@@ -158,7 +158,7 @@ protected static SetItemNode createSetItem() {
         }
     }
 
-    @CApiBuiltin(ret = Void, args = {PyObject, Py_ssize_t, PyObjectBorrowed}, call = Direct)
+    @CApiBuiltin(ret = Void, args = {PyObject, Py_ssize_t, PyObjectTransfer}, call = Direct)
     abstract static class PyTruffleTuple_SET_ITEM extends CApiTernaryBuiltinNode {
         @Specialization
         static Object doManaged(PTuple tuple, long index, Object element,