array-species-constructor-delete.js 986 Bytes
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// Copyright 2016 the V8 project authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

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// Flags: --allow-natives-syntax
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// Overwriting the constructor of an instance updates the protector

let x = [];

assertEquals(Array, x.map(()=>{}).constructor);
assertEquals(Array, x.filter(()=>{}).constructor);
assertEquals(Array, x.slice().constructor);
assertEquals(Array, x.splice().constructor);
assertEquals(Array, x.concat([1]).constructor);
assertEquals(1, x.concat([1])[0]);

class MyArray extends Array { }

Object.prototype.constructor = MyArray;
delete Array.prototype.constructor;
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assertFalse(%ArraySpeciesProtector());
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assertEquals(MyArray, x.map(()=>{}).constructor);
assertEquals(MyArray, x.filter(()=>{}).constructor);
assertEquals(MyArray, x.slice().constructor);
assertEquals(MyArray, x.splice().constructor);
assertEquals(MyArray, x.concat([1]).constructor);
assertEquals(1, x.concat([1])[0]);