save(): Fix for SF bug #494904: Cannot pickle a class with a
metaclass, reported by Dan Parisien.
Objects that are instances of custom metaclasses, i.e. whose ob_type
is a subclass of PyType_Type, should be pickled the same as new-style
classes (objects whose ob_type is PyType_Type). This can't be done
through the existing dispatch switches, and the __reduce__ trick
doesn't work for these, since it finds the unbound __reduce__ for
instances of the class (inherited from PyBaseObject_Type). So check
explicitly using PyType_IsSubtype().
diff --git a/Modules/cPickle.c b/Modules/cPickle.c
index 425ff10..a4943ce 100644
--- a/Modules/cPickle.c
+++ b/Modules/cPickle.c
@@ -1990,6 +1990,11 @@
}
}
+ if (PyType_IsSubtype(type, &PyType_Type)) {
+ res = save_global(self, args, NULL);
+ goto finally;
+ }
+
if (!pers_save && self->inst_pers_func) {
if ((tmp = save_pers(self, args, self->inst_pers_func)) != 0) {
res = tmp;