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// |reftest| shell-option(--enable-iterator-helpers) skip-if(!this.hasOwnProperty('Iterator')||!xulRuntime.shell) -- iterator-helpers is not enabled unconditionally, requires shell-options
// Copyright (C) 2023 Michael Ficarra. All rights reserved.
// This code is governed by the BSD license found in the LICENSE file.
/*---
esid: sec-iterator.from
description: >
The value of the [[Prototype]] internal slot of the return value of Iterator.from is the
intrinsic object %WrapForValidIteratorPrototype%, whose [[Prototype]] is %IteratorHelperPrototype%.
features: [iterator-helpers]
---*/
let iter = {
next() {
return {
done: true,
value: undefined,
};
},
};
const WrapForValidIteratorPrototype = Object.getPrototypeOf(Iterator.from(iter));
assert.sameValue(Object.getPrototypeOf(WrapForValidIteratorPrototype), Iterator.prototype);
class SubIterator extends Iterator {}
assert.sameValue(Object.getPrototypeOf(SubIterator.from(iter)), WrapForValidIteratorPrototype);
function* g() {}
const GeneratorPrototype = Object.getPrototypeOf(g());
assert.sameValue(Object.getPrototypeOf(Iterator.from(g())), GeneratorPrototype);
reportCompare(0, 0);