// Copyright 2024 the V8 project authors. All rights reserved. // Use of this source code is governed by a BSD-style license that can be // found in the LICENSE file. // Flags: --allow-natives-syntax --expose-gc --move-prototype-transitions-first // Check proto transitions are applied first (function() { var p = {}; var x1 = {}; x1.a = 1; x1.__proto__ = p; var x2 = {}; x2.__proto__ = p; x2.a = 1; assertTrue(%HaveSameMap(x1, x2)); })(); // Check proto transitions can be undone (function() { var x1 = {}; x1.a = 1; var x2 = {}; x2.a = 1; x2.__proto__ = {}; x2.__proto__ = x1.__proto__; assertTrue(%HaveSameMap(x1, x2)); })(); // Checks that intermediate maps don't die after proto transitions (function() { function foo() {} function goo() {} var p = new goo(); function test() { var o = new foo(); o.middle = 2; o.__proto__ = p; return o; } var a = test(); gc();gc();gc(); var b = test(); assertTrue(%HaveSameMap(a,b)); })(); // Checks if slack tracking on derived maps updates actual root map (function() { function bla(a,b){} pro = new Proxy({},{}); var co = function(){} co.prototype = new Proxy({}, {get(target, property) {return 1}}); Reflect.construct(bla, [], co); Reflect.construct(bla, [], co); Reflect.construct(bla, [], co); Reflect.construct(bla, [], co); Reflect.construct(bla, [], co); Reflect.construct(bla, [], co); Reflect.construct(bla, [], co); var x = new bla(); x.__proto__ = co.prototype; })();