| // Copyright (C) 2015 André Bargull. All rights reserved. |
| // This code is governed by the BSD license found in the LICENSE file. |
| |
| /*--- |
| info: Mapped arguments object with non-configurable property |
| description: > |
| Mapped arguments property is changed to non-configurable and |
| non-writable. Perform property attribute changes with two |
| [[DefineOwnProperty]] calls. Add intervening call to |
| SetMutableBinding. |
| flags: [noStrict] |
| ---*/ |
| |
| function argumentsNonConfigurableThenNonWritableWithInterveningSetMutableBinding(a) { |
| Object.defineProperty(arguments, "0", {configurable: false}); |
| a = 2; |
| Object.defineProperty(arguments, "0", {writable: false}); |
| assert.sameValue(a, 2); |
| // `arguments[0] === 1` per ES2015, Rev 38, April 14, 2015 Final Draft. |
| // Specification bug: https://bugs.ecmascript.org/show_bug.cgi?id=4371 |
| assert.sameValue(arguments[0], 2); |
| |
| // Postcondition: Arguments mapping is removed. |
| a = 3; |
| assert.sameValue(a, 3); |
| assert.sameValue(arguments[0], 2); |
| } |
| argumentsNonConfigurableThenNonWritableWithInterveningSetMutableBinding(1); |