Add JS_GetMethod to the JS API, to cope with E4X's breaking the var f=o.m;f.apply(o,arguments)===o.m() invariant; qualify bogus assert in jsemit.c to make it righteous; use JS_GetMethod from nsXPCWrappedJSClass::CallMethod (246441, r=me).

js/src/jsapi.c

@@ -2597,6 +2597,35 @@ JS_GetProperty(JSContext *cx, JSObject *obj, const char *name, jsval *vp)
     return OBJ_GET_PROPERTY(cx, obj, ATOM_TO_JSID(atom), vp);
 }
 
+JS_PUBLIC_API(JSBool)
+JS_GetMethod(JSContext *cx, JSObject *obj, const char *name, JSObject **objp,
+             jsval *vp)
+{
+    JSAtom *atom;
+    jsid id;
+
+    CHECK_REQUEST(cx);
+    atom = js_Atomize(cx, name, strlen(name), 0);
+    if (!atom)
+        return JS_FALSE;
+    id = ATOM_TO_JSID(atom);
+
+    if (OBJECT_IS_XML(cx, obj)) {
+        JSXMLObjectOps *ops;
+
+        ops = (JSXMLObjectOps *) obj->map->ops;
+        obj = ops->getMethod(cx, obj, id, vp);
+        if (!obj)
+            return JS_FALSE;
+    } else {
+        if (!OBJ_GET_PROPERTY(cx, obj, id, vp))
+            return JS_FALSE;
+    }
+
+    *objp = obj;
+    return JS_TRUE;
+}
+
 JS_PUBLIC_API(JSBool)
 JS_SetProperty(JSContext *cx, JSObject *obj, const char *name, jsval *vp)
 {

js/src/jsapi.h

@@ -1097,6 +1097,10 @@ JS_LookupPropertyWithFlags(JSContext *cx, JSObject *obj, const char *name,
 extern JS_PUBLIC_API(JSBool)
 JS_GetProperty(JSContext *cx, JSObject *obj, const char *name, jsval *vp);
 
+extern JS_PUBLIC_API(JSBool)
+JS_GetMethod(JSContext *cx, JSObject *obj, const char *name, JSObject **objp,
+             jsval *vp);
+
 extern JS_PUBLIC_API(JSBool)
 JS_SetProperty(JSContext *cx, JSObject *obj, const char *name, jsval *vp);
 

js/src/jsemit.c

@@ -4289,7 +4289,9 @@ js_EmitTree(JSContext *cx, JSCodeGenerator *cg, JSParseNode *pn)
          */
         pn2 = pn->pn_head;
 #if JS_HAS_XML_SUPPORT
-        if (JS_HAS_XML_OPTION(cx) && pn2->pn_type == TOK_DOT) {
+        if (JS_HAS_XML_OPTION(cx) &&
+            pn2->pn_type == TOK_DOT &&
+            pn2->pn_op != JSOP_GETMETHOD) {
             JS_ASSERT(pn2->pn_op == JSOP_GETPROP);
             pn2->pn_op = JSOP_GETMETHOD;
         }

js/src/xpconnect/src/xpcwrappedjsclass.cpp

@@ -1118,7 +1118,7 @@ nsXPCWrappedJSClass::CallMethod(nsXPCWrappedJS* wrapper, uint16 methodIndex,
                 }
             }
         }
-        else if(!JS_GetProperty(cx, obj, name, &fval))
+        else if(!JS_GetMethod(cx, obj, name, &thisObj, &fval))
         {
             // XXX We really want to factor out the error reporting better and
             // specifically report the failure to find a function with this name.