trap-is-undefined-target-is-proxy.js (1300B)
1 // Copyright (C) 2020 Alexey Shvayka. All rights reserved. 2 // This code is governed by the BSD license found in the LICENSE file. 3 4 /*--- 5 esid: sec-proxy-object-internal-methods-and-internal-slots-getownproperty-p 6 description: > 7 If "getOwnPropertyDescriptor" trap is null or undefined, [[GetOwnProperty]] 8 call is properly forwarded to [[ProxyTarget]] (which is also a Proxy object). 9 info: | 10 [[GetOwnProperty]] ( P ) 11 12 [...] 13 5. Let target be O.[[ProxyTarget]]. 14 6. Let trap be ? GetMethod(handler, "getOwnPropertyDescriptor"). 15 7. If trap is undefined, then 16 a. Return ? target.[[GetOwnProperty]](P). 17 includes: [propertyHelper.js] 18 features: [Proxy] 19 ---*/ 20 21 var arrayTarget = new Proxy([42], {}); 22 var arrayProxy = new Proxy(arrayTarget, { 23 getOwnPropertyDescriptor: undefined, 24 }); 25 26 verifyProperty(arrayProxy, "0", { 27 value: 42, 28 writable: true, 29 enumerable: true, 30 configurable: true, 31 }); 32 33 verifyProperty(arrayProxy, "length", { 34 value: 1, 35 // writable: true, 36 enumerable: false, 37 configurable: false, 38 }); 39 40 41 var regExpTarget = new Proxy(/(?:)/, {}); 42 var regExpProxy = new Proxy(regExpTarget, { 43 getOwnPropertyDescriptor: undefined, 44 }); 45 46 verifyProperty(regExpProxy, "lastIndex", { 47 value: 0, 48 writable: true, 49 enumerable: false, 50 configurable: false, 51 }); 52 53 reportCompare(0, 0);