[Python-checkins] r77159 - in python/branches/release26-maint: Doc/c-api/structures.rst Lib/test/test_descr.py Misc/NEWS Python/structmember.c

[benjamin.peterson]

Author: benjamin.peterson
Date: Wed Dec 30 20:41:48 2009
New Revision: 77159

Log:
Merged revisions 77157 via svnmerge from 
svn+ssh://pythondev@svn.python.org/python/trunk

........
  r77157 | benjamin.peterson | 2009-12-30 13:34:10 -0600 (Wed, 30 Dec 2009) | 5 lines
  
  check if the attribute is set before deleting it with T_OBJECT_EX (fixes #7604)
  
  Also, add a note to the docs about the better behavior of T_OBJECT_EX as
  compared to T_OBJECT.
........


Modified:
   python/branches/release26-maint/   (props changed)
   python/branches/release26-maint/Doc/c-api/structures.rst
   python/branches/release26-maint/Lib/test/test_descr.py
   python/branches/release26-maint/Misc/NEWS
   python/branches/release26-maint/Python/structmember.c

Modified: python/branches/release26-maint/Doc/c-api/structures.rst
==============================================================================
--- python/branches/release26-maint/Doc/c-api/structures.rst	(original)
+++ python/branches/release26-maint/Doc/c-api/structures.rst	Wed Dec 30 20:41:48 2009
@@ -281,7 +281,10 @@
 
    :cmacro:`T_OBJECT` and :cmacro:`T_OBJECT_EX` differ in that
    :cmacro:`T_OBJECT` returns ``None`` if the member is *NULL* and
-   :cmacro:`T_OBJECT_EX` raises an :exc:`AttributeError`.
+   :cmacro:`T_OBJECT_EX` raises an :exc:`AttributeError`.  Try to use
+   :cmacro:`T_OBJECT_EX` over :cmacro:`T_OBJECT` because :cmacro:`T_OBJECT_EX`
+   handles use of the :stmt:`del` statement on that attribute more correctly
+   than :cmacro:`T_OBJECT`.
 
    :attr:`flags` can be 0 for write and read access or :cmacro:`READONLY` for
    read-only access.  Using :cmacro:`T_STRING` for :attr:`type` implies

Modified: python/branches/release26-maint/Lib/test/test_descr.py
==============================================================================
--- python/branches/release26-maint/Lib/test/test_descr.py	(original)
+++ python/branches/release26-maint/Lib/test/test_descr.py	Wed Dec 30 20:41:48 2009
@@ -1142,6 +1142,11 @@
             del h
         self.assertEqual(s.getvalue(), '')
 
+        class X(object):
+            __slots__ = "a"
+        with self.assertRaises(AttributeError):
+            del X().a
+
     def test_slots_special(self):
         # Testing __dict__ and __weakref__ in __slots__...
         class D(object):

Modified: python/branches/release26-maint/Misc/NEWS
==============================================================================
--- python/branches/release26-maint/Misc/NEWS	(original)
+++ python/branches/release26-maint/Misc/NEWS	Wed Dec 30 20:41:48 2009
@@ -12,6 +12,9 @@
 Core and Builtins
 -----------------
 
+- Issue #7604: Deleting an unset slotted attribute did not raise an
+  AttributeError.
+
 - Issue #7413: Passing '\0' as the separator to datetime.datetime.isoformat()
   used to drop the time part of the result.
 

Modified: python/branches/release26-maint/Python/structmember.c
==============================================================================
--- python/branches/release26-maint/Python/structmember.c	(original)
+++ python/branches/release26-maint/Python/structmember.c	Wed Dec 30 20:41:48 2009
@@ -170,6 +170,8 @@
 {
 	PyObject *oldv;
 
+	addr += l->offset;
+
 	if ((l->flags & READONLY) || l->type == T_STRING)
 	{
 		PyErr_SetString(PyExc_TypeError, "readonly attribute");
@@ -179,12 +181,20 @@
 		PyErr_SetString(PyExc_RuntimeError, "restricted attribute");
 		return -1;
 	}
-	if (v == NULL && l->type != T_OBJECT_EX && l->type != T_OBJECT) {
-		PyErr_SetString(PyExc_TypeError,
-				"can't delete numeric/char attribute");
-		return -1;
+	if (v == NULL) {
+		if (l->type == T_OBJECT_EX) {
+			/* Check if the attribute is set. */
+			if (*(PyObject **)addr == NULL) {
+				PyErr_SetString(PyExc_AttributeError, l->name);
+				return -1;
+			}
+		}
+		else if (l->type != T_OBJECT) {
+			PyErr_SetString(PyExc_TypeError,
+					"can't delete numeric/char attribute");
+			return -1;
+		}
 	}
-	addr += l->offset;
 	switch (l->type) {
 	case T_BOOL:{
 		if (!PyBool_Check(v)) {