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// |reftest| async
// This file was procedurally generated from the following sources:
// - src/dstr-assignment-for-await/array-rest-nested-obj-undefined.case
// - src/dstr-assignment-for-await/default/async-gen-decl.template
/*---
description: When DestructuringAssignmentTarget is an obect literal and the iterable is emits no values, an empty array should be used as the value of the nested DestructuringAssignment. (for-await-of statement in an async generator declaration)
esid: sec-for-in-and-for-of-statements-runtime-semantics-labelledevaluation
features: [destructuring-binding, async-iteration]
flags: [generated, async]
info: |
IterationStatement :
for await ( LeftHandSideExpression of AssignmentExpression ) Statement
1. Let keyResult be the result of performing ? ForIn/OfHeadEvaluation(« »,
AssignmentExpression, iterate).
2. Return ? ForIn/OfBodyEvaluation(LeftHandSideExpression, Statement,
keyResult, assignment, labelSet).
13.7.5.13 Runtime Semantics: ForIn/OfBodyEvaluation
[...]
5. If destructuring is true and if lhsKind is assignment, then
a. Assert: lhs is a LeftHandSideExpression.
b. Let assignmentPattern be the parse of the source text corresponding to
lhs using AssignmentPattern as the goal symbol.
[...]
---*/
let x = null;
// Use the the top-level lexical scope for 'length' to provide compatibility with browsers
// where length and name are properties of WindowProxy
let length;
let iterCount = 0;
async function * fn() {
for await ([...{ 0: x, length }] of [[]]) {
assert.sameValue(x, undefined);
assert.sameValue(length, 0);
iterCount += 1;
}
}
let promise = fn().next();
promise
.then(() => assert.sameValue(iterCount, 1, 'iteration occurred as expected'), $DONE)
.then($DONE, $DONE);