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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 mapper is passed the yielded value and a counter as arguments
info: |
%Iterator.prototype%.flatMap ( mapper )
5.b.iv. Let mapped be Completion(Call(mapper, undefined, « value, 𝔽(counter) »)).
features: [iterator-helpers]
flags: []
---*/
function* g() {
yield 'a';
yield 'b';
yield 'c';
yield 'd';
yield 'e';
}
let assertionCount = 0;
let iter = g().flatMap((v, count) => {
switch (v) {
case 'a':
assert.sameValue(count, 0);
++assertionCount;
return [0];
case 'b':
assert.sameValue(count, 1);
++assertionCount;
return [0];
case 'c':
assert.sameValue(count, 2);
++assertionCount;
return [1, 2];
case 'd':
assert.sameValue(count, 3);
++assertionCount;
return [3, 4, 5];
case 'e':
assert.sameValue(count, 4);
++assertionCount;
return [6, 7, 8, 9];
default:
throw new Error();
}
});
assert.sameValue(assertionCount, 0);
for (let i of iter);
assert.sameValue(assertionCount, 5);
reportCompare(0, 0);
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