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// |reftest| async
// This file was procedurally generated from the following sources:
// - src/function-forms/dflt-params-arg-val-undefined.case
// - src/function-forms/default/async-arrow-function.template
/*---
description: Use of initializer when argument value is `undefined` (async arrow function expression)
esid: sec-async-arrow-function-definitions
features: [default-parameters, async-functions]
flags: [generated, async]
info: |
14.7 Async Arrow Function Definitions
AsyncArrowFunction :
...
CoverCallExpressionAndAsyncArrowHead => AsyncConciseBody
AsyncConciseBody :
{ AsyncFunctionBody }
...
Supplemental Syntax
When processing an instance of the production AsyncArrowFunction :
CoverCallExpressionAndAsyncArrowHead => AsyncConciseBody the interpretation of
CoverCallExpressionAndAsyncArrowHead is refined using the following grammar:
AsyncArrowHead :
async ArrowFormalParameters
14.1.19 Runtime Semantics: IteratorBindingInitialization
FormalsList : FormalsList , FormalParameter
[...]
23. Let iteratorRecord be Record {[[Iterator]]:
CreateListIterator(argumentsList), [[Done]]: false}.
24. If hasDuplicates is true, then
[...]
25. Else,
a. Perform ? IteratorBindingInitialization for formals with
iteratorRecord and env as arguments.
[...]
---*/
var callCount = 0;
// Stores a reference `ref` for case evaluation
var ref = async (fromLiteral = 23, fromExpr = 45, fromHole = 99) => {
assert.sameValue(fromLiteral, 23);
assert.sameValue(fromExpr, 45);
assert.sameValue(fromHole, 99);
callCount = callCount + 1;
};
ref(undefined, void 0).then(() => {
assert.sameValue(callCount, 1, 'async arrow function invoked exactly once')
}).then($DONE, $DONE);