merge 3.1

Lib/test/test_descr.py

@@ -1587,6 +1587,7 @@ def format_impl(self, spec):
             ("__floor__", math.floor, zero, set(), {}),
             ("__trunc__", math.trunc, zero, set(), {}),
             ("__ceil__", math.ceil, zero, set(), {}),
+            ("__dir__", dir, empty_seq, set(), {}),
             ]
 
         class Checker(object):

Misc/NEWS

@@ -13,6 +13,9 @@ Core and Builtins
 Library
 -------
 
+- Correct lookup of __dir__ on objects. Among other things, this causes errors
+  besides AttributeError found on lookup to be propagated.
+
 - Issue #12124: zipimport doesn't keep a reference to zlib.decompress() anymore
   to be able to unload the module.
 

Objects/object.c

@@ -1366,14 +1366,15 @@ _generic_dir(PyObject *obj)
 static PyObject *
 _dir_object(PyObject *obj)
 {
-    PyObject * result = NULL;
-    PyObject * dirfunc = PyObject_GetAttrString((PyObject*)obj->ob_type,
-                                                "__dir__");
+    PyObject *result = NULL;
+    static PyObject *dir_str = NULL;
+    PyObject *dirfunc = _PyObject_LookupSpecial(obj, "__dir__", &dir_str);
 
     assert(obj);
     if (dirfunc == NULL) {
+        if (PyErr_Occurred())
+            return NULL;
         /* use default implementation */
-        PyErr_Clear();
         if (PyModule_Check(obj))
             result = _specialized_dir_module(obj);
         else if (PyType_Check(obj))
@@ -1383,7 +1384,7 @@ _dir_object(PyObject *obj)
     }
     else {
         /* use __dir__ */
-        result = PyObject_CallFunctionObjArgs(dirfunc, obj, NULL);
+        result = PyObject_CallFunctionObjArgs(dirfunc, NULL);
         Py_DECREF(dirfunc);
         if (result == NULL)
             return NULL;