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// |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%.return
description: return() will return a iterator result object when built-in sync throw is called
info: |
%AsyncFromSyncIteratorPrototype%.return ( value )
...
2. Let promiseCapability be ! NewPromiseCapability(%Promise%).
...
5. Let return be GetMethod(syncIterator, "return").
...
8. Let returnResult be Call(return, syncIterator, « value »).
...
22. Return promiseCapability.[[Promise]].
Generator.prototype.return ( value )
1. Let g be the this value.
2. Let C be Completion{[[Type]]: return, [[Value]]: value, [[Target]]: empty}.
3. Return ? GeneratorResumeAbrupt(g, C).
flags: [async]
features: [async-iteration]
---*/
function* g() {
yield 42;
throw new Test262Error('return closes iter');
yield 43;
}
async function* asyncg() {
yield* g();
}
var iter = asyncg();
var val = 'some specific return value'
iter.next().then(function(result) {
// return will call sync generator prototype built-in function return
iter.return(val).then(function(result) {
assert.sameValue(result.done, true, 'the iterator is completed');
assert.sameValue(result.value, val, 'expect agrument to `return`');
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);
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