#6428: py3k requires that __bool__ return a bool (and not an int)

Fix the error message and the documentation.

Doc/reference/datamodel.rst

@@ -1254,11 +1254,11 @@ Basic customization
    .. index:: single: __len__() (mapping object method)
 
    Called to implement truth value testing and the built-in operation
-   ``bool()``; should return ``False`` or ``True``, or their integer equivalents
+   ``bool()``; should return ``False`` or ``True``.  When this method is not
-   ``0`` or ``1``.  When this method is not defined, :meth:`__len__` is called,
+   defined, :meth:`__len__` is called, if it is defined, and the object is
-   if it is defined, and the object is considered true if its result is nonzero.
+   considered true if its result is nonzero.  If a class defines neither
-   If a class defines neither :meth:`__len__` nor :meth:`__bool__`, all its
+   :meth:`__len__` nor :meth:`__bool__`, all its instances are considered
-   instances are considered true.
+   true.
 
 
 .. _attribute-access:

Misc/NEWS

@@ -12,6 +12,10 @@ What's New in Python 3.2 Alpha 1?
 Core and Builtins
 -----------------
 
+- Issue #6428: Since Python 3.0, the __bool__ method must return a bool
+  object, and not an int.  Fix the corresponding error message, and the
+  documentation.
+
 - The deprecated PyCObject has been removed.
 
 - Issue #6347: Include inttypes.h as well as stdint.h in pyport.h.

Objects/typeobject.c

@@ -4807,10 +4807,8 @@ slot_nb_bool(PyObject *self)
 			}
 			else {
 				PyErr_Format(PyExc_TypeError,
-					     "%s should return "
+					     "__bool__ should return "
-					     "bool or int, returned %s",
+					     "bool, returned %s",
-					     (using_len ? "__len__"
-					                : "__bool__"),
 					     Py_TYPE(temp)->tp_name);
 				result = -1;
 			}