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// |reftest| async
// This file was procedurally generated from the following sources:
// - src/dstr-binding/ary-ptrn-elem-id-init-skipped.case
// - src/dstr-binding/default/async-gen-func-decl-dflt.template
/*---
description: Destructuring initializer is not evaluated when value is not `undefined` (async generator function declaration (default parameter))
esid: sec-asyncgenerator-definitions-instantiatefunctionobject
features: [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
SingleNameBinding : BindingIdentifier Initializeropt
[...]
6. If Initializer is present and v is undefined, then
[...]
7. If environment is undefined, return PutValue(lhs, v).
8. Return InitializeReferencedBinding(lhs, v).
---*/
var initCount = 0;
function counter() {
initCount += 1;
}
var callCount = 0;
async function* f([w = counter(), x = counter(), y = counter(), z = counter()] = [null, 0, false, '']) {
assert.sameValue(w, null);
assert.sameValue(x, 0);
assert.sameValue(y, false);
assert.sameValue(z, '');
assert.sameValue(initCount, 0);
callCount = callCount + 1;
};
f().next().then(() => {
assert.sameValue(callCount, 1, 'invoked exactly once');
}).then($DONE, $DONE);
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