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// |reftest| skip-if(!this.hasOwnProperty('Iterator'))
//
//
/*---
esid: pending
description: Lazy %Iterator.prototype% methods handle empty iterators.
info: >
Iterator Helpers proposal 2.1.5
features: [iterator-helpers]
---*/
class EmptyIterator extends Iterator {
next() {
return {done: true};
}
}
const emptyIterator1 = new EmptyIterator();
const emptyIterator2 = [].values();
const methods = [
iter => iter.map(x => x),
iter => iter.filter(x => x),
iter => iter.take(1),
iter => iter.drop(0),
iter => iter.flatMap(x => [x]),
];
for (const method of methods) {
for (const iterator of [emptyIterator1, emptyIterator2]) {
const result = method(iterator).next();
assertEq(result.done, true);
assertEq(result.value, undefined);
}
}
if (typeof reportCompare == 'function')
reportCompare(0, 0);