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// |reftest| skip-if(!this.hasOwnProperty('Iterator'))
//
//
/*---
esid: pending
description: Calling `.return()` on a lazy %Iterator.prototype% method multiple times closes the source iterator once.
info: >
Iterator Helpers proposal 2.1.5
features: [iterator-helpers]
---*/
class TestIterator extends Iterator {
next() {
return {done: false, value: 1};
}
closeCount = 0;
return(value) {
this.closeCount++;
return {done: true, value};
}
}
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]),
];
// Call `return` after stepping the iterator once:
for (const method of methods) {
const iter = new TestIterator();
const iterHelper = method(iter);
iterHelper.next();
assertEq(iter.closeCount, 0);
iterHelper.return();
assertEq(iter.closeCount, 1);
iterHelper.return();
assertEq(iter.closeCount, 1);
}
// Call `return` before stepping the iterator:
for (const method of methods) {
const iter = new TestIterator();
const iterHelper = method(iter);
assertEq(iter.closeCount, 0);
iterHelper.return();
assertEq(iter.closeCount, 1);
iterHelper.return();
assertEq(iter.closeCount, 1);
}
if (typeof reportCompare == 'function')
reportCompare(0, 0);