30 lines
727 B
JavaScript
30 lines
727 B
JavaScript
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// Copyright 2018 the V8 project authors. All rights reserved.
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// Use of this source code is governed by a BSD-style license that can be
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// found in the LICENSE file.
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{
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class MyArray extends Array {
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static get [Symbol.species]() {
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return Array;
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}
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}
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const wannabe = new MyArray();
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const result = wannabe.flatMap(x => [x, x]);
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assertEquals(false, result instanceof MyArray);
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assertEquals(true, result instanceof Array);
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}
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{
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class MyArray extends Array {
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static get [Symbol.species]() {
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return this;
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}
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}
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const wannabe = new MyArray();
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const result = wannabe.flatMap(x => [x, x]);
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assertEquals(true, result instanceof MyArray);
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assertEquals(true, result instanceof Array);
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}
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