gh-105035: fix super() calls on unusual types (e.g. meta-types) (#105094)

Author: carljm

Lib/test/test_super.py

@@ -410,6 +410,18 @@ def method(self):
 
         self.assertEqual(C().method(), mysuper)
 
+    def test_unusual_getattro(self):
+        class MyType(type):
+            pass
+
+        def test(name):
+            mytype = MyType(name, (MyType,), {})
+            super(MyType, type(mytype)).__setattr__(mytype, "bar", 1)
+            self.assertEqual(mytype.bar, 1)
+
+        test("foo1")
+        test("foo2")
+
 
 if __name__ == "__main__":
     unittest.main()

Misc/NEWS.d/next/Core and Builtins/2023-05-30-08-09-43.gh-issue-105035.OWUlHy.rst

@@ -0,0 +1,2 @@
+Fix :func:`super` calls on types with custom :attr:`tp_getattro`
+implementation (e.g. meta-types.)

Python/bytecodes.c

@@ -1660,8 +1660,10 @@ dummy_func(
             DEOPT_IF(!PyType_Check(class), LOAD_SUPER_ATTR);
             STAT_INC(LOAD_SUPER_ATTR, hit);
             PyObject *name = GETITEM(frame->f_code->co_names, oparg >> 2);
+            PyTypeObject *cls = (PyTypeObject *)class;
             int method_found = 0;
-            res2 = _PySuper_Lookup((PyTypeObject *)class, self, name, &method_found);
+            res2 = _PySuper_Lookup(cls, self, name,
+                                   cls->tp_getattro == PyObject_GenericGetAttr ? &method_found : NULL);
             Py_DECREF(global_super);
             Py_DECREF(class);
             if (res2 == NULL) {