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// |reftest| async
// This file was procedurally generated from the following sources:
// - src/dstr-binding-for-await/ary-ptrn-elision.case
// - src/dstr-binding-for-await/default/for-await-of-async-gen-let-async.template
/*---
description: Elision advances iterator (for-await-of statement)
esid: sec-for-in-and-for-of-statements-runtime-semantics-labelledevaluation
features: [generators, destructuring-binding, async-iteration]
flags: [generated, async]
info: |
IterationStatement :
for await ( ForDeclaration of AssignmentExpression ) Statement
[...]
2. Return ? ForIn/OfBodyEvaluation(ForDeclaration, Statement, keyResult,
lexicalBinding, labelSet, async).
13.7.5.13 Runtime Semantics: ForIn/OfBodyEvaluation
[...]
4. Let destructuring be IsDestructuring of lhs.
[...]
6. Repeat
[...]
j. If destructuring is false, then
[...]
k. Else
i. If lhsKind is assignment, then
[...]
ii. Else if lhsKind is varBinding, then
[...]
iii. Else,
1. Assert: lhsKind is lexicalBinding.
2. Assert: lhs is a ForDeclaration.
3. Let status be the result of performing BindingInitialization
for lhs passing nextValue and iterationEnv as arguments.
[...]
13.3.3.6 Runtime Semantics: IteratorBindingInitialization
ArrayBindingPattern : [ Elision ]
1. Return the result of performing
IteratorDestructuringAssignmentEvaluation of Elision with iteratorRecord
as the argument.
12.14.5.3 Runtime Semantics: IteratorDestructuringAssignmentEvaluation
Elision : ,
1. If iteratorRecord.[[done]] is false, then
a. Let next be IteratorStep(iteratorRecord.[[iterator]]).
b. If next is an abrupt completion, set iteratorRecord.[[done]] to true.
c. ReturnIfAbrupt(next).
d. If next is false, set iteratorRecord.[[done]] to true.
2. Return NormalCompletion(empty).
---*/
var first = 0;
var second = 0;
function* g() {
first += 1;
yield;
second += 1;
};
var iterCount = 0;
var asyncIter = (async function*() {
yield* [g()];
})();
async function *fn() {
for await (let [,] of asyncIter) {
assert.sameValue(first, 1);
assert.sameValue(second, 0);
iterCount += 1;
}
}
fn().next()
.then(() => assert.sameValue(iterCount, 1, 'iteration occurred as expected'), $DONE)
.then($DONE, $DONE);