| // Copyright 2016 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. |
| |
| // Create a prototype object which has a lot of fast properties. |
| var body = ""; |
| for (var i = 0; i < 100; i++) { |
| body += `this.a${i} = 0;\n`; |
| } |
| var Proto = new Function(body); |
| |
| function A() {} |
| A.prototype = new Proto(); |
| |
| // Create a object and add properties that already exist in the prototype. |
| // At some point the object will turn into a dictionary mode and one of |
| // the fast details from the prototype will be reinterpreted as a details |
| // for a new property ... |
| var o = new A(); |
| for (var i = 0; i < 100; i++) { |
| o["a" + i] = i; |
| } |
| |
| // ... which will break the enumeration order of the slow properties. |
| var names = Object.getOwnPropertyNames(o); |
| for (var i = 0; i < 100; i++) { |
| assertEquals("a" + i, names[i]); |
| } |