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// |reftest| skip-if(!this.hasOwnProperty('Iterator'))
//
/*---
esid: pending
description: Lazy %Iterator.prototype% methods access specified properties only.
info: >
features: [iterator-helpers]
---*/
class TestIterator extends Iterator {
value = 0;
next() {
if (this.value < 2)
return { done: false, value: this.value++ };
return { done: true, value: undefined };
}
}
const handlerProxy = log => new Proxy({}, {
get: (target, key, receiver) => (...args) => {
const target = args[0];
const item = Reflect[key](...args);
log.push(`${key}: ${args.filter(x => typeof x != 'object').map(x => x.toString())}`);
return item;
},
});
const methods = [
[iter => iter.map(x => x), 'map'],
[iter => iter.filter(x => true), 'filter'],
[iter => iter.take(4), 'take'],
[iter => iter.drop(0), 'drop'],
[iter => iter.flatMap(x => [x]), 'flatMap'],
];
for (const method of methods) {
const log = [];
const iteratorProxy = new Proxy(new TestIterator(), handlerProxy(log));
const iteratorHelper = method[0](iteratorProxy);
const methodName = method[1];
iteratorHelper.next();
iteratorHelper.next();
iteratorHelper.next();
assertEq(iteratorHelper.next().done, true);
assertEq(
log.join('\n'),
`get: ${methodName}
get: next
get: value
get: value
getOwnPropertyDescriptor: value
defineProperty: value
set: value,1
get: value
get: value
getOwnPropertyDescriptor: value
defineProperty: value
set: value,2
get: value`
)
}
if (typeof reportCompare == 'function')
reportCompare(0, 0);