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// |reftest| async
// This file was procedurally generated from the following sources:
// - src/dstr-binding/ary-ptrn-rest-ary-elision.case
// - src/dstr-binding/default/async-gen-func-decl-dflt.template
/*---
description: Rest element containing an elision (async generator function declaration (default parameter))
esid: sec-asyncgenerator-definitions-instantiatefunctionobject
features: [generators, async-iteration]
flags: [generated, async]
info: |
AsyncGeneratorDeclaration : async [no LineTerminator here] function * BindingIdentifier
( FormalParameters ) { AsyncGeneratorBody }
[...]
3. Let F be ! AsyncGeneratorFunctionCreate(Normal, FormalParameters, AsyncGeneratorBody,
scope, strict).
[...]
13.3.3.6 Runtime Semantics: IteratorBindingInitialization
BindingRestElement : ... BindingPattern
1. Let A be ArrayCreate(0).
[...]
3. Repeat
[...]
b. If iteratorRecord.[[done]] is true, then
i. Return the result of performing BindingInitialization of
BindingPattern with A and environment as the 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 callCount = 0;
async function* f([...[,]] = g()) {
assert.sameValue(first, 1);
assert.sameValue(second, 1);
callCount = callCount + 1;
};
f().next().then(() => {
assert.sameValue(callCount, 1, 'invoked exactly once');
}).then($DONE, $DONE);
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