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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-iteratorprototype.flatMap
description: >
Iterator.prototype.flatMap falls back to treating mapper return values as iterators if the Symbol.iterator property is null/undefined
info: |
%Iterator.prototype%.flatMap ( mapper )
5.b.vi. Let innerIterator be Completion(GetIteratorFlattenable(mapped)).
includes: [compareArray.js]
features: [iterator-helpers]
flags: []
---*/
function* g() {
yield 0;
}
function* h() {
yield 0;
yield 1;
yield 2;
}
let iter = g().flatMap(v => {
let n = h();
return {
[Symbol.iterator]: 0,
next: () => n.next(),
};
});
assert.throws(TypeError, function () {
iter.next();
});
iter = g().flatMap(v => {
let n = h();
return {
[Symbol.iterator]: null,
next: () => n.next(),
};
});
assert.compareArray(Array.from(iter), [0, 1, 2]);
iter = g().flatMap(v => {
let n = h();
return {
[Symbol.iterator]: undefined,
next: () => n.next(),
};
});
assert.compareArray(Array.from(iter), [0, 1, 2]);
reportCompare(0, 0);
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