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// |reftest| async
// This file was procedurally generated from the following sources:
// - src/dstr-binding/ary-ptrn-elem-id-iter-val-array-prototype.case
// - src/dstr-binding/default/async-gen-func-decl.template
/*---
description: Array destructuring uses overriden Array.prototype[Symbol.iterator] (async generator function declaration)
esid: sec-asyncgenerator-definitions-instantiatefunctionobject
features: [Symbol.iterator, 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).
[...]
Runtime Semantics: IteratorBindingInitialization
SingleNameBinding : BindingIdentifier Initializer_opt
1. Let bindingId be StringValue of BindingIdentifier.
2. Let lhs be ? ResolveBinding(bindingId, environment).
3. If iteratorRecord.[[Done]] is false, then
a. Let next be IteratorStep(iteratorRecord).
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.
e. Else,
i. Let v be IteratorValue(next).
ii. If v is an abrupt completion, set iteratorRecord.[[Done]] to true.
iii. ReturnIfAbrupt(v).
[...]
7. Return InitializeReferencedBinding(lhs, v).
---*/
Array.prototype[Symbol.iterator] = function* () {
if (this.length > 0) {
yield this[0];
}
if (this.length > 1) {
yield this[1];
}
if (this.length > 2) {
yield 42;
}
};
var callCount = 0;
async function* f([x, y, z]) {
assert.sameValue(x, 1);
assert.sameValue(y, 2);
assert.sameValue(z, 42);
callCount = callCount + 1;
};
f([1, 2, 3]).next().then(() => {
assert.sameValue(callCount, 1, 'invoked exactly once');
}).then($DONE, $DONE);
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