// |reftest| async // Copyright (C) 2018 Valerie Young. All rights reserved. // This code is governed by the BSD license found in the LICENSE file. /*--- esid: sec-%asyncfromsynciteratorprototype%.throw description: return() will return value undefined if sync `return` is undefined info: | %AsyncFromSyncIteratorPrototype%.return ( value ) ... 2. Let promiseCapability be ! NewPromiseCapability(%Promise%). ... 5. Let return be GetMethod(syncIterator, "return"). 6. IfAbruptRejectPromise(return, promiseCapability). 7. If return is undefined, then a. Let iterResult be ! CreateIterResultObject(value, true). b. Perform ! Call(promiseCapability.[[Resolve]], undefined, « iterResult »). c. Return promiseCapability.[[Promise]]. flags: [async] features: [async-iteration] ---*/ var obj = { [Symbol.iterator]() { return { next() { return { value: 1, done: false }; } }; } }; async function* asyncg() { yield* obj; } var iter = asyncg(); iter.next().then(function(result) { iter.return().then(function(result) { assert.sameValue(result.done, true, 'the iterator is completed'); assert.sameValue(result.value, undefined, 'expect value to be undefined'); iter.next().then(({ done, value }) => { assert.sameValue(done, true, 'the iterator is completed'); assert.sameValue(value, undefined, 'value is undefined'); }).then($DONE, $DONE); }).catch($DONE); }).catch($DONE);