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// |reftest| async
// This file was procedurally generated from the following sources:
// - src/dstr-binding/ary-ptrn-elem-ary-empty-init.case
// - src/dstr-binding/default/async-gen-func-named-expr-dflt.template
/*---
description: BindingElement with array binding pattern and initializer is used (async generator named function expression (default parameter))
esid: sec-asyncgenerator-definitions-evaluation
features: [generators, async-iteration]
flags: [generated, async]
info: |
AsyncGeneratorExpression : async [no LineTerminator here] function * BindingIdentifier
( FormalParameters ) { AsyncGeneratorBody }
[...]
7. Let closure be ! AsyncGeneratorFunctionCreate(Normal, FormalParameters,
AsyncGeneratorBody, funcEnv, strict).
[...]
13.3.3.6 Runtime Semantics: IteratorBindingInitialization
BindingElement : BindingPatternInitializer opt
[...]
2. If iteratorRecord.[[done]] is true, let v be undefined.
3. If Initializer is present and v is undefined, then
a. Let defaultValue be the result of evaluating Initializer.
b. Let v be ? GetValue(defaultValue).
4. Return the result of performing BindingInitialization of BindingPattern
with v and environment as the arguments.
---*/
var initCount = 0;
var iterCount = 0;
var iter = function*() { iterCount += 1; }();
var callCount = 0;
var f;
f = async function* h([[] = function() { initCount += 1; return iter; }()] = []) {
assert.sameValue(initCount, 1);
assert.sameValue(iterCount, 0);
callCount = callCount + 1;
};
f().next().then(() => {
assert.sameValue(callCount, 1, 'invoked exactly once');
}).then($DONE, $DONE);