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// |reftest| async
// Copyright (C) 2020 Alexey Shvayka. All rights reserved.
// This code is governed by the BSD license found in the LICENSE file.
/*---
esid: sec-generator-function-definitions-runtime-semantics-evaluation
description: >
If iterator's "throw" method is `null`,
AsyncIteratorClose is called before rising TypeError.
info: |
YieldExpression : yield * AssignmentExpression
[...]
7. Repeat,
[...]
b. Else if received.[[Type]] is throw, then
i. Let throw be ? GetMethod(iterator, "throw").
ii. If throw is not undefined, then
[...]
iii. Else,
[...]
3. If generatorKind is async, perform ? AsyncIteratorClose(iteratorRecord, closeCompletion).
[...]
6. Throw a TypeError exception.
GetMethod ( V, P )
[...]
2. Let func be ? GetV(V, P).
3. If func is either undefined or null, return undefined.
AsyncIteratorClose ( iteratorRecord, completion )
[...]
4. Let innerResult be GetMethod(iterator, "return").
5. If innerResult.[[Type]] is normal, then
a. Let return be innerResult.[[Value]].
b. If return is undefined, return Completion(completion).
features: [Symbol.asyncIterator, async-iteration]
flags: [async]
---*/
var throwGets = 0;
var returnGets = 0;
var asyncIterable = {
[Symbol.asyncIterator]: function() {
return this;
},
next: function() {
return {value: 1, done: false};
},
get throw() {
throwGets += 1;
return null;
},
get return() {
returnGets += 1;
},
};
async function* asyncGenerator() {
yield* asyncIterable;
}
var asyncIterator = asyncGenerator();
asyncIterator.next().then(function() {
return asyncIterator.throw();
}).then(function(result) {
throw new Test262Error("Promise should be rejected, got: " + result.value);
}, function(err) {
assert.sameValue(err.constructor, TypeError);
assert.sameValue(throwGets, 1);
assert.sameValue(returnGets, 1);
}).then($DONE, $DONE);