diff options
| -rw-r--r-- | Objects/typeobject.c | 74 |
1 files changed, 46 insertions, 28 deletions
diff --git a/Objects/typeobject.c b/Objects/typeobject.c index a3fefe6..c369ff7 100644 --- a/Objects/typeobject.c +++ b/Objects/typeobject.c @@ -1236,8 +1236,8 @@ static PyObject * type_getattro(PyTypeObject *type, PyObject *name) { PyTypeObject *metatype = type->ob_type; - PyObject *descr, *res; - descrgetfunc f; + PyObject *meta_attribute, *attribute; + descrgetfunc meta_get; /* Initialize this type (we'll assume the metatype is initialized) */ if (type->tp_dict == NULL) { @@ -1245,40 +1245,58 @@ type_getattro(PyTypeObject *type, PyObject *name) return NULL; } - /* Get a descriptor from the metatype */ - descr = _PyType_Lookup(metatype, name); - f = NULL; - if (descr != NULL) { - f = descr->ob_type->tp_descr_get; - if (f != NULL && PyDescr_IsData(descr)) - return f(descr, - (PyObject *)type, (PyObject *)metatype); + /* No readable descriptor found yet */ + meta_get = NULL; + + /* Look for the attribute in the metatype */ + meta_attribute = _PyType_Lookup(metatype, name); + + if (meta_attribute != NULL) { + meta_get = meta_attribute->ob_type->tp_descr_get; + + if (meta_get != NULL && PyDescr_IsData(meta_attribute)) { + /* Data descriptors implement tp_descr_set to intercept + * writes. Assume the attribute is not overridden in + * type's tp_dict (and bases): call the descriptor now. + */ + return meta_get(meta_attribute, (PyObject *)type, + (PyObject *)metatype); + } } - /* Look in tp_dict of this type and its bases */ - res = _PyType_Lookup(type, name); - if (res != NULL) { - f = res->ob_type->tp_descr_get; - if (f != NULL) - return f(res, (PyObject *)NULL, (PyObject *)type); - Py_INCREF(res); - return res; + /* No data descriptor found on metatype. Look in tp_dict of this + * type and its bases */ + attribute = _PyType_Lookup(type, name); + if (attribute != NULL) { + /* Implement descriptor functionality, if any */ + descrgetfunc local_get = attribute->ob_type->tp_descr_get; + if (local_get != NULL) { + /* NULL 2nd argument indicates the descriptor was + * found on the target object itself (or a base) */ + return local_get(attribute, (PyObject *)NULL, + (PyObject *)type); + } + + Py_INCREF(attribute); + return attribute; } - /* Use the descriptor from the metatype */ - if (f != NULL) { - res = f(descr, (PyObject *)type, (PyObject *)metatype); - return res; - } - if (descr != NULL) { - Py_INCREF(descr); - return descr; + /* No attribute found in local __dict__ (or bases): use the + * descriptor from the metatype, if any */ + if (meta_get != NULL) + return meta_get(meta_attribute, (PyObject *)type, + (PyObject *)metatype); + + /* If an ordinary attribute was found on the metatype, return it now */ + if (meta_attribute != NULL) { + Py_INCREF(meta_attribute); + return meta_attribute; } /* Give up */ PyErr_Format(PyExc_AttributeError, - "type object '%.50s' has no attribute '%.400s'", - type->tp_name, PyString_AS_STRING(name)); + "type object '%.50s' has no attribute '%.400s'", + type->tp_name, PyString_AS_STRING(name)); return NULL; } |