Strict mode Passingnon-Strict mode Passing
Features:
- ∅
// Copyright (C) 2022 Apple Inc. All rights reserved. // This code is governed by the BSD license found in the LICENSE file. /*--- esid: sec-array.prototype.unshift description: > A TypeError is thrown when "length" is [[Set]] on a frozen array. info: | Array.prototype.unshift ( ...items ) [...] 4. If argCount > 0, then [...] d. Let j be +0𝔽. e. For each element E of items, do i. Perform ? Set(O, ! ToString(j), E, true). ii. Set j to j + 1𝔽. 5. Perform ? Set(O, "length", 𝔽(len + argCount), true). OrdinarySetWithOwnDescriptor ( O, P, V, Receiver, ownDesc ) [...] 2. If IsDataDescriptor(ownDesc) is true, then a. If ownDesc.[[Writable]] is false, return false. Set ( O, P, V, Throw ) [...] 1. Let success be ? O.[[Set]](P, V, O). 2. If success is false and Throw is true, throw a TypeError exception. ---*/ var array = []; var arrayPrototypeSet0Calls = 0; Object.defineProperty(Array.prototype, "0", { set(_val) { Object.freeze(array); arrayPrototypeSet0Calls++; }, }); assert.throws(TypeError, function() { array.unshift(1); }); assert(!array.hasOwnProperty(0)); assert.sameValue(array.length, 0); assert.sameValue(arrayPrototypeSet0Calls, 1);