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// |reftest| shell-option(--enable-iterator-sequencing) skip-if(!Iterator.concat||!xulRuntime.shell) -- iterator-sequencing is not enabled unconditionally, requires shell-options
// Copyright (C) 2024 André Bargull and Michael Ficarra. All rights reserved.
// This code is governed by the BSD license found in the LICENSE file.
/*---
esid: sec-iterator.concat
description: >
The value of the [[Prototype]] internal slot of the return value of Iterator.concat
is the intrinsic object %IteratorHelperPrototype%.
features: [iterator-sequencing]
---*/
var iter = Iterator.concat();
assert(iter instanceof Iterator, "Iterator.concat() must return an Iterator");
var customIter = { next() { return { done: true, value: undefined }; } };
iter = Iterator.concat({ [Symbol.iterator]() { return customIter; } });
assert(iter instanceof Iterator, "Iterator.concat(...) must return an Iterator");
reportCompare(0, 0);