https://hg.python.org/cpython/rev/18ed518d2eef changeset: 105388:18ed518d2eef parent: 105386:9ded2433dc2c parent: 105387:6b8f7d1e2ba4 user: Serhiy Storchaka <storchaka@gmail.com> date: Tue Nov 29 09:56:07 2016 +0200 summary: Issue #28797: Modifying the class __dict__ inside the __set_name__ method of a descriptor that is used inside that class no longer prevents calling the __set_name__ method of other descriptors. files: Lib/test/test_subclassinit.py | 16 ++++++++++++++++ Misc/NEWS | 4 ++++ Objects/typeobject.c | 18 +++++++++++++----- 3 files changed, 33 insertions(+), 5 deletions(-) diff --git a/Lib/test/test_subclassinit.py b/Lib/test/test_subclassinit.py --- a/Lib/test/test_subclassinit.py +++ b/Lib/test/test_subclassinit.py @@ -198,6 +198,22 @@ self.assertIs(B.meta_owner, B) self.assertEqual(B.name, 'd') + def test_set_name_modifying_dict(self): + notified = [] + class Descriptor: + def __set_name__(self, owner, name): + setattr(owner, name + 'x', None) + notified.append(name) + + class A: + a = Descriptor() + b = Descriptor() + c = Descriptor() + d = Descriptor() + e = Descriptor() + + self.assertCountEqual(notified, ['a', 'b', 'c', 'd', 'e']) + def test_errors(self): class MyMeta(type): pass diff --git a/Misc/NEWS b/Misc/NEWS --- a/Misc/NEWS +++ b/Misc/NEWS @@ -10,6 +10,10 @@ Core and Builtins ----------------- +- Issue #28797: Modifying the class __dict__ inside the __set_name__ method of + a descriptor that is used inside that class no longer prevents calling the + __set_name__ method of other descriptors. + - Issue #28799: Remove the ``PyEval_GetCallStats()`` function and deprecate the untested and undocumented ``sys.callstats()`` function. Remove the ``CALL_PROFILE`` special build: use the :func:`sys.setprofile` function, diff --git a/Objects/typeobject.c b/Objects/typeobject.c --- a/Objects/typeobject.c +++ b/Objects/typeobject.c @@ -7004,10 +7004,14 @@ static int set_names(PyTypeObject *type) { - PyObject *key, *value, *set_name, *tmp; + PyObject *names_to_set, *key, *value, *set_name, *tmp; Py_ssize_t i = 0; - while (PyDict_Next(type->tp_dict, &i, &key, &value)) { + names_to_set = PyDict_Copy(type->tp_dict); + if (names_to_set == NULL) + return -1; + + while (PyDict_Next(names_to_set, &i, &key, &value)) { set_name = lookup_maybe(value, &PyId___set_name__); if (set_name != NULL) { tmp = PyObject_CallFunctionObjArgs(set_name, type, key, NULL); @@ -7017,15 +7021,19 @@ "Error calling __set_name__ on '%.100s' instance %R " "in '%.100s'", value->ob_type->tp_name, key, type->tp_name); + Py_DECREF(names_to_set); return -1; } else Py_DECREF(tmp); } - else if (PyErr_Occurred()) + else if (PyErr_Occurred()) { + Py_DECREF(names_to_set); return -1; - } - + } + } + + Py_DECREF(names_to_set); return 0; } -- Repository URL: https://hg.python.org/cpython