[Python-checkins] r78505 - in python/branches/py3k: Lib/test/test_metaclass.py Misc/NEWS Python/bltinmodule.c

[benjamin.peterson]

Author: benjamin.peterson
Date: Sat Feb 27 18:40:01 2010
New Revision: 78505

Log:
only accept AttributeError as indicating no __prepare__ attribute on a metaclass, allowing lookup errors to propogate

Modified:
   python/branches/py3k/Lib/test/test_metaclass.py
   python/branches/py3k/Misc/NEWS
   python/branches/py3k/Python/bltinmodule.c

Modified: python/branches/py3k/Lib/test/test_metaclass.py
==============================================================================
--- python/branches/py3k/Lib/test/test_metaclass.py	(original)
+++ python/branches/py3k/Lib/test/test_metaclass.py	Sat Feb 27 18:40:01 2010
@@ -230,6 +230,20 @@
     42
     >>>
 
+Test failures in looking up the __prepare__ method work.
+    >>> class ObscureException(Exception):
+    ...     pass
+    >>> class FailDescr:
+    ...     def __get__(self, instance, owner):
+    ...        raise ObscureException
+    >>> class Meta(type):
+    ...     __prepare__ = FailDescr()
+    >>> class X(metaclass=Meta):
+    ...     pass
+    Traceback (most recent call last):
+    [...]
+    test.test_metaclass.ObscureException
+
 """
 
 __test__ = {'doctests' : doctests}

Modified: python/branches/py3k/Misc/NEWS
==============================================================================
--- python/branches/py3k/Misc/NEWS	(original)
+++ python/branches/py3k/Misc/NEWS	Sat Feb 27 18:40:01 2010
@@ -12,6 +12,8 @@
 Core and Builtins
 -----------------
 
+- Handle errors from looking up __prepare__ correctly.
+
 - Issue #5939: Add additional runtime checking to ensure a valid capsule
   in Modules/_ctypes/callproc.c.
 

Modified: python/branches/py3k/Python/bltinmodule.c
==============================================================================
--- python/branches/py3k/Python/bltinmodule.c	(original)
+++ python/branches/py3k/Python/bltinmodule.c	Sat Feb 27 18:40:01 2010
@@ -108,8 +108,16 @@
 	}
 	prep = PyObject_GetAttrString(meta, "__prepare__");
 	if (prep == NULL) {
-		PyErr_Clear();
-		ns = PyDict_New();
+		if (PyErr_ExceptionMatches(PyExc_AttributeError)) {
+			PyErr_Clear();
+			ns = PyDict_New();
+		}
+		else {
+			Py_DECREF(meta);
+			Py_XDECREF(mkw);
+			Py_DECREF(bases);
+			return NULL;
+		}
 	}
 	else {
 		PyObject *pargs = PyTuple_Pack(2, name, bases);