// Copyright (C) 2017 Caio Lima. All rights reserved. // This code is governed by the BSD license found in the LICENSE file. /*--- description: Mapped arguments property descriptor change to non-configurable and non-writable info: > Mapping just stop working when property is set to non-writable. Change the descriptor using [[DefineOwnProperty]] to {configurable: false}, set arguments[0] = 2 and then change property descriptor to {writable: false}. The descriptor's value need to be the one set before the property be configured as {writable: false}. flags: [noStrict] esid: sec-arguments-exotic-objects-defineownproperty-p-desc includes: [propertyHelper.js] ---*/ function fn(a) { Object.defineProperty(arguments, "0", {configurable: false}); arguments[0] = 2; Object.defineProperty(arguments, "0", {writable: false}); let propertyDescriptor = Object.getOwnPropertyDescriptor(arguments, "0"); assert.sameValue(propertyDescriptor.value, 2); assert.sameValue(a, 2) verifyEnumerable(arguments, "0"); verifyNotWritable(arguments, "0"); verifyNotConfigurable(arguments, "0"); // Postcondition: Arguments mapping is removed. a = 3; propertyDescriptor = Object.getOwnPropertyDescriptor(arguments, "0"); assert.sameValue(propertyDescriptor.value, 2); verifyEnumerable(arguments, "0"); verifyNotWritable(arguments, "0"); verifyNotConfigurable(arguments, "0"); } fn(1);