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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: >
Iterator.from does not respect the iterability of any primitive except Strings
info: |
Iterator.from ( O )
1. If O is a String, set O to ! ToObject(O).
2. Let iteratorRecord be ? GetIteratorFlattenable(O).
includes: [compareArray.js]
features: [iterator-helpers]
flags: []
---*/
function* g() {
yield 0;
}
Number.prototype[Symbol.iterator] = function* () {
let i = 0;
let target = this >>> 0;
while (i < target) {
yield i;
++i;
}
};
assert.compareArray(Array.from(5), [0, 1, 2, 3, 4]);
assert.throws(TypeError, function () {
Iterator.from(5);
});
assert.compareArray(Array.from(Iterator.from(new Number(5))), [0, 1, 2, 3, 4]);
assert.compareArray(Array.from(Iterator.from('string')), ['s', 't', 'r', 'i', 'n', 'g']);
const originalStringIterator = String.prototype[Symbol.iterator];
let observedType;
Object.defineProperty(String.prototype, Symbol.iterator, {
get() {
'use strict';
observedType = typeof this;
return originalStringIterator;
}
});
Iterator.from('');
assert.sameValue(observedType, 'string');
Iterator.from(new String(''));
assert.sameValue(observedType, 'object');
reportCompare(0, 0);
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