Make isinstance() more permissive in what types of arguments it

accepts. Clarify exception messages for isinstance() and
issubclass().  Closes bug #124106.

diff --git a/Python/bltinmodule.c b/Python/bltinmodule.c
index 7c8cf187e3a7c0f5be29c4894485ae4a1ab62826..fa560f7dc8dccd91a9149c21706cc5472db0277e 100644 (file)
--- a/Python/bltinmodule.c
+++ b/Python/bltinmodule.c
@@ -1995,7 +1995,7 @@ Without arguments, equivalent to locals().\n\
 With an argument, equivalent to object.__dict__.";
 
 static int
-abstract_issubclass(PyObject *derived, PyObject *cls, char *err, int first)
+abstract_issubclass(PyObject *derived, PyObject *cls, int first)
 {
        static PyObject *__bases__ = NULL;
        PyObject *bases;
@@ -2012,7 +2012,8 @@ abstract_issubclass(PyObject *derived, PyObject *cls, char *err, int first)
                bases = PyObject_GetAttr(cls, __bases__);
                if (bases == NULL || !PyTuple_Check(bases)) {
                        Py_XDECREF(bases);
-                       PyErr_SetString(PyExc_TypeError, err);
+                       PyErr_SetString(PyExc_TypeError,
+                                       "arg 2 must be a class or type");
                        return -1;
                }
                Py_DECREF(bases);
@@ -2024,14 +2025,14 @@ abstract_issubclass(PyObject *derived, PyObject *cls, char *err, int first)
        bases = PyObject_GetAttr(derived, __bases__);
        if (bases == NULL || !PyTuple_Check(bases)) {
                Py_XDECREF(bases);
-               PyErr_SetString(PyExc_TypeError, err);
+               PyErr_SetString(PyExc_TypeError,
+                               "arg 2 must be a class or type");
                return -1;
        }
 
        n = PyTuple_GET_SIZE(bases);
        for (i = 0; i < n; i++) {
-               r = abstract_issubclass(PyTuple_GET_ITEM(bases, i),
-                                       cls, err, 0);
+               r = abstract_issubclass(PyTuple_GET_ITEM(bases, i), cls, 0);
                if (r != 0)
                        break;
        }
@@ -2071,25 +2072,17 @@ builtin_isinstance(PyObject *self, PyObject *args)
                }
                icls = PyObject_GetAttr(inst, __class__);
                if (icls != NULL) {
-                       retval = abstract_issubclass(
-                               icls, cls,
-                               "isinstance() arg 2 must be a class", 
-                               1);
+                       retval = abstract_issubclass( icls, cls, 1);
                        Py_DECREF(icls);
                        if (retval < 0)
                                return NULL;
                }
                else {
                        PyErr_SetString(PyExc_TypeError,
-                                       "isinstance() arg 2 must be a class");
+                                       "arg 2 must be a class or type");
                        return NULL;
                }
        }
-        else {
-               PyErr_SetString(PyExc_TypeError,
-                               "isinstance() arg 2 must be a class");
-               return NULL;
-       }
        return PyInt_FromLong(retval);
 }
 
@@ -2111,8 +2104,7 @@ builtin_issubclass(PyObject *self, PyObject *args)
                return NULL;
 
        if (!PyClass_Check(derived) || !PyClass_Check(cls)) {
-               retval = abstract_issubclass(
-                               derived, cls, "arguments must be classes", 1);
+               retval = abstract_issubclass(derived, cls, 1);
                if (retval < 0) 
                        return NULL;
        }