// 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.push description: > A TypeError is thrown when "length" is [[Set]] on an array with non-writable "length". info: | Array.prototype.push ( ...items ) [...] 5. For each element E of items, do a. Perform ? Set(O, ! ToString(𝔽(len)), E, true). b. Set len to len + 1. 6. Perform ? Set(O, "length", 𝔽(len), 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.defineProperty(array, "length", { writable: false }); arrayPrototypeSet0Calls++; }, }); assert.throws(TypeError, function() { array.push(1); }); assert(!array.hasOwnProperty(0)); assert.sameValue(array.length, 0); assert.sameValue(arrayPrototypeSet0Calls, 1); reportCompare(0, 0);