properly implement cmp() for class instances

diff --git a/Objects/object.c b/Objects/object.c
index c19d96ff371f4a1bffd4e64a460ba76ca5e2b828..be3cce7e809909a3a94d9783733c536bf94b3ada 100644 (file)
--- a/Objects/object.c
+++ b/Objects/object.c
@@ -201,6 +201,19 @@ strobject(v)
        }
 }
 
+static object *
+do_cmp(v, w)
+       object *v, *w;
+{
+       /* __rcmp__ actually won't be called unless __cmp__ isn't defined,
+          because the check in cmpobject() reverses the objects first.
+          This is intentional -- it makes no sense to define cmp(x,y) different
+          than -cmp(y,x). */
+       if (is_instanceobject(v) || is_instanceobject(w))
+               return instancebinop(v, w, "__cmp__", "__rcmp__", do_cmp);
+       return newintobject((long)cmpobject(v, w));
+}
+
 int
 cmpobject(v, w)
        object *v, *w;
@@ -212,6 +225,24 @@ cmpobject(v, w)
                return -1;
        if (w == NULL)
                return 1;
+       if (is_instanceobject(v) || is_instanceobject(w)) {
+               object *res;
+               int c;
+               if (!is_instanceobject(v))
+                       return -cmpobject(w, v);
+               res = do_cmp(v, w);
+               if (res == NULL) {
+                       err_clear();
+                       return (v < w) ? -1 : 1;
+               }
+               if (!is_intobject(res)) {
+                       DECREF(res);
+                       return (v < w) ? -1 : 1;
+               }
+               c = getintvalue(res);
+               DECREF(res);
+               return (c < 0) ? -1 : (c > 0) ? 1 : 0;  
+       }
        if ((tp = v->ob_type) != w->ob_type) {
                if (tp->tp_as_number != NULL &&
                                w->ob_type->tp_as_number != NULL) {