traverseda
/
cpython
1
0
Fork 0
Code Issues Pull Requests Releases Wiki Activity

Fix error checking done by abstract_issubclass and abstract_isinstance. 

isinstance() now allows any object as the first argument and a class, a
type or something with a __bases__ tuple attribute for the second
argument.  This closes SF patch #464992.
This commit is contained in:
Neil Schemenauer 2001-10-18 03:18:43 +00:00
parent 9f6c37df26
commit 6b47129424
1 changed files with 62 additions and 45 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

107
Objects/abstract.c
View File

@ -1740,45 +1740,46 @@ PyObject_CallMethod(PyObject *o, char *name, char *format, ...)
/* isinstance(), issubclass() */
static int
abstract_issubclass(PyObject *derived, PyObject *cls, int first)
static PyObject *
abstract_get_bases(PyObject *cls)
{
static PyObject *__bases__ = NULL;
PyObject *bases;
int i, n;
int r = 0;
if (__bases__ == NULL) {
__bases__ = PyString_FromString("__bases__");
if (__bases__ == NULL)
return -1;
return NULL;
}
if (first) {
bases = PyObject_GetAttr(cls, __bases__);
if (bases == NULL || !PyTuple_Check(bases)) {
Py_XDECREF(bases);
PyErr_SetString(PyExc_TypeError,
"issubclass() arg 2 must be a class");
return -1;
}
Py_DECREF(bases);
bases = PyObject_GetAttr(cls, __bases__);
if (bases == NULL || !PyTuple_Check(bases)) {
Py_XDECREF(bases);
return NULL;
}
return bases;
}
static int
abstract_issubclass(PyObject *derived, PyObject *cls)
{
PyObject *bases;
int i, n;
int r = 0;
if (derived == cls)
return 1;
bases = PyObject_GetAttr(derived, __bases__);
if (bases == NULL || !PyTuple_Check(bases)) {
Py_XDECREF(bases);
PyErr_SetString(PyExc_TypeError,
"issubclass() arg 1 must be a class");
return -1;
}
bases = abstract_get_bases(derived);
if (bases == NULL)
return 0;
n = PyTuple_GET_SIZE(bases);
for (i = 0; i < n; i++) {
r = abstract_issubclass(PyTuple_GET_ITEM(bases, i), cls, 0);
r = abstract_issubclass(PyTuple_GET_ITEM(bases, i), cls);
if (r != 0)
break;
}
@ -1795,12 +1796,10 @@ PyObject_IsInstance(PyObject *inst, PyObject *cls)
static PyObject *__class__ = NULL;
int retval = 0;
if (PyClass_Check(cls)) {
if (PyInstance_Check(inst)) {
PyObject *inclass =
(PyObject*)((PyInstanceObject*)inst)->in_class;
retval = PyClass_IsSubclass(inclass, cls);
}
if (PyClass_Check(cls) && PyInstance_Check(inst)) {
PyObject *inclass =
(PyObject*)((PyInstanceObject*)inst)->in_class;
retval = PyClass_IsSubclass(inclass, cls);
}
else if (PyType_Check(cls)) {
retval = PyObject_TypeCheck(inst, (PyTypeObject *)cls);
@ -1819,31 +1818,30 @@ PyObject_IsInstance(PyObject *inst, PyObject *cls)
}
return retval;
}
else if (!PyInstance_Check(inst)) {
else {
PyObject *cls_bases = abstract_get_bases(cls);
if (cls_bases == NULL) {
PyErr_SetString(PyExc_TypeError,
"isinstance() arg 2 must be a class or type");
return -1;
}
Py_DECREF(cls_bases);
if (__class__ == NULL) {
__class__ = PyString_FromString("__class__");
if (__class__ == NULL)
return -1;
}
icls = PyObject_GetAttr(inst, __class__);
if (icls != NULL) {
retval = abstract_issubclass(icls, cls, 1);
Py_DECREF(icls);
if (retval < 0 &&
!PyErr_ExceptionMatches(PyExc_TypeError))
return -1;
if (icls == NULL) {
PyErr_Clear();
retval = 0;
}
else {
retval = abstract_issubclass(icls, cls);
Py_DECREF(icls);
}
else
retval = -1;
}
else
retval = -1;
if (retval < 0) {
PyErr_SetString(PyExc_TypeError,
"isinstance() arg 2 must be a class or type "
"or tuple of those");
}
return retval;
}
@ -1853,7 +1851,26 @@ PyObject_IsSubclass(PyObject *derived, PyObject *cls)
int retval;
if (!PyClass_Check(derived) || !PyClass_Check(cls)) {
retval = abstract_issubclass(derived, cls, 1);
PyObject *derived_bases;
PyObject *cls_bases;
derived_bases = abstract_get_bases(derived);
if (derived_bases == NULL) {
PyErr_SetString(PyExc_TypeError,
"issubclass() arg 1 must be a class");
return -1;
}
Py_DECREF(derived_bases);
cls_bases = abstract_get_bases(cls);
if (cls_bases == NULL) {
PyErr_SetString(PyExc_TypeError,
"issubclass() arg 2 must be a class");
return -1;
}
Py_DECREF(cls_bases);
retval = abstract_issubclass(derived, cls);
}
else {
/* shortcut */