nonconfigurable-nonenumerable-nonwritable-descriptors-set-by-arguments.js (1180B)
1 // Copyright (C) 2017 Caio Lima. All rights reserved. 2 // This code is governed by the BSD license found in the LICENSE file. 3 4 /*--- 5 description: Mapped arguments property descriptor change to non-configurable, non-enumerable and non-writable 6 info: | 7 Change the descriptor using [[DefineOwnProperty]] to {configurable: false, enumerable: false}, 8 set arguments[0] = 2 and then change property descriptor to {writable: false}. 9 The descriptor's enumerable property is the one set before the mapping removal. 10 flags: [noStrict] 11 esid: sec-arguments-exotic-objects-defineownproperty-p-desc 12 includes: [propertyHelper.js] 13 ---*/ 14 15 function fn(a) { 16 Object.defineProperty(arguments, "0", {configurable: false, enumerable: false}); 17 arguments[0] = 2; 18 Object.defineProperty(arguments, "0", {writable: false}); 19 20 assert.sameValue(a, 2); 21 22 verifyProperty(arguments, "0", { 23 value: 2, 24 writable: false, 25 enumerable: false, 26 configurable: false, 27 }); 28 29 // Postcondition: Arguments mapping is removed. 30 a = 3; 31 32 verifyProperty(arguments, "0", { 33 value: 2, 34 writable: false, 35 enumerable: false, 36 configurable: false, 37 }); 38 } 39 fn(1); 40 41 42 reportCompare(0, 0);