regular-subclassing.js (785B)
1 // Copyright (C) 2016 the V8 project authors. All rights reserved. 2 // This code is governed by the BSD license found in the LICENSE file. 3 /*--- 4 es6id: 23.2.1 5 description: Subclassing the Set object 6 info: | 7 23.2.1 The Set Constructor 8 9 ... 10 11 The Set constructor is designed to be subclassable. It may be used as the 12 value in an extends clause of a class definition. Subclass constructors that 13 intend to inherit the specified Set behaviour must include a super call to the 14 Set constructor to create and initialize the subclass instance with the 15 internal state necessary to support the Set.prototype built-in methods. 16 ---*/ 17 18 class S extends Set {} 19 20 var set = new S([{}, {}]); 21 22 assert.sameValue(set.size, 2); 23 24 set.add({}); 25 26 assert.sameValue(set.size, 3); 27 28 reportCompare(0, 0);