Fix: wrap native descriptor get/set functions.

Author: fangerer

graalpython/com.oracle.graal.python.cext/src/typeobject.c

@@ -95,6 +95,18 @@ static PyObject* wrap_setattrofunc(setattrofunc f, PyObject* obj, PyObject* key,
 	return PyLong_FromLong(f(obj, key, item));
 }
 
+/* Basically the same as 'wrap_setattrofunc' but has a different function type. */
+static PyObject* wrap_descrsetfunc(descrsetfunc f, PyObject* obj, PyObject* key, PyObject* item) {
+	if(f(obj, key, item) < 0) {
+		return NULL;
+	}
+	return Py_None;
+}
+
+static PyObject* wrap_descrgetfunc(descrgetfunc f, PyObject* self, PyObject* obj, PyObject* type) {
+	return native_to_java(f(self, obj, type));
+}
+
 static PyObject* wrap_richcmpfunc(richcmpfunc f, PyObject* a, PyObject* b, PyObject* n) {
 	return f(a, b, (int)PyLong_AsLong(n));
 }
@@ -424,8 +436,8 @@ int PyType_Ready(PyTypeObject* cls) {
     }
     ADD_SLOT("__iter__", cls->tp_iter, -1);
     ADD_SLOT("__next__", cls->tp_iternext, -1);
-    ADD_SLOT("__get__", cls->tp_descr_get, -3);
-    ADD_SLOT("__set__", cls->tp_descr_set, -3);
+    ADD_SLOT_CONV("__get__", wrap_descrgetfunc, cls->tp_descr_get, -3);
+    ADD_SLOT_CONV("__set__", wrap_descrsetfunc, cls->tp_descr_set, -3);
     ADD_SLOT_CONV("__init__", wrap_initproc, cls->tp_init, METH_KEYWORDS | METH_VARARGS);
     ADD_SLOT_CONV("__alloc__", wrap_allocfunc, cls->tp_alloc, -2);
     ADD_SLOT("__new__", cls->tp_new, METH_KEYWORDS | METH_VARARGS);

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

@@ -505,8 +505,8 @@ def CPyExtType(name, code, **kwargs):
         0,                          /* tp_getset */
         {tp_base},                  /* tp_base */
         {tp_dict},                  /* tp_dict */
-        0,                          /* tp_descr_get */
-        0,                          /* tp_descr_set */
+        {tp_descr_get},             /* tp_descr_get */
+        {tp_descr_set},             /* tp_descr_set */
         {tp_dictoffset},            /* tp_dictoffset */
         {tp_init},                  /* tp_init */
         PyType_GenericAlloc,        /* tp_alloc */

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

@@ -315,6 +315,33 @@ class TestCustomBasicsizeSubclass(TestCustomBasicsize):
         assert expected_basicsize == actual_basicsize, "expected = %s, actual = %s" % (expected_basicsize, actual_basicsize)
 
 
+    def test_descrset(self):
+        TestDescrSet = CPyExtType("TestDescrSet",
+                             '''
+                             int testdescr_set(PyObject* self, PyObject* key, PyObject* value) {
+                                     Py_XDECREF(((TestDescrSetObject*)self)->payload);
+                                     Py_XINCREF(value);
+                                     ((TestDescrSetObject*)self)->payload = value;
+                                     return 0;
+                             }
+
+                             PyObject* testdescr_get(PyObject* self, PyObject* key, PyObject* type) {
+                                     return ((TestDescrSetObject*)self)->payload;
+                             }
+                             ''',
+                             cmembers='PyObject* payload;',
+                             tp_descr_set="(descrsetfunc) testdescr_set",
+                             tp_descr_get="(descrgetfunc) testdescr_get",
+        )
+        
+        class Uff:
+            hello = TestDescrSet()
+        
+        obj = Uff()
+        obj.hello = "world"
+        assert obj.hello == "world", 'expected "world" but was %s' % obj.hello
+
+
 class TestObjectFunctions(CPyExtTestCase):
     def compile_module(self, name):
         type(self).mro()[1].__dict__["test_%s" % name].create_module(name)