SF #532767: isinstance(x, X) should work when x is a proxy for an X
instance, as long as x.__class__ is X or a subclass thereof.
Did a little cleanup of PyObject_IsInstance() too.
diff --git a/Objects/abstract.c b/Objects/abstract.c
index abc7e70..45d2206 100644
--- a/Objects/abstract.c
+++ b/Objects/abstract.c
@@ -2040,6 +2040,12 @@
static PyObject *__class__ = NULL;
int retval = 0;
+ if (__class__ == NULL) {
+ __class__ = PyString_FromString("__class__");
+ if (__class__ == NULL)
+ return -1;
+ }
+
if (PyClass_Check(cls) && PyInstance_Check(inst)) {
PyObject *inclass =
(PyObject*)((PyInstanceObject*)inst)->in_class;
@@ -2047,6 +2053,19 @@
}
else if (PyType_Check(cls)) {
retval = PyObject_TypeCheck(inst, (PyTypeObject *)cls);
+ if (retval == 0) {
+ PyObject *c = PyObject_GetAttr(inst, __class__);
+ if (c == NULL) {
+ PyErr_Clear();
+ }
+ else {
+ if (c != inst->ob_type && PyType_Check(c))
+ retval = PyType_IsSubtype(
+ (PyTypeObject *)c,
+ (PyTypeObject *)cls);
+ Py_DECREF(c);
+ }
+ }
}
else if (PyTuple_Check(cls)) {
/* Not a general sequence -- that opens up the road to
@@ -2060,18 +2079,12 @@
if (retval != 0)
break;
}
- return retval;
}
else {
if (!check_class(cls,
"isinstance() arg 2 must be a class, type,"
" or tuple of classes and types"))
return -1;
- if (__class__ == NULL) {
- __class__ = PyString_FromString("__class__");
- if (__class__ == NULL)
- return -1;
- }
icls = PyObject_GetAttr(inst, __class__);
if (icls == NULL) {
PyErr_Clear();