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// This file was procedurally generated from the following sources:
// - src/function-forms/dflt-params-arg-val-undefined.case
// - src/function-forms/default/gen-func-expr.template
/*---
description: Use of initializer when argument value is `undefined` (generator function expression)
esid: sec-generator-function-definitions-runtime-semantics-evaluation
features: [default-parameters, generators]
flags: [generated]
info: |
GeneratorExpression : function * ( FormalParameters ) { GeneratorBody }
[...]
3. Let closure be GeneratorFunctionCreate(Normal, FormalParameters,
GeneratorBody, scope, strict).
[...]
9.2.1 [[Call]] ( thisArgument, argumentsList)
[...]
7. Let result be OrdinaryCallEvaluateBody(F, argumentsList).
[...]
9.2.1.3 OrdinaryCallEvaluateBody ( F, argumentsList )
1. Let status be FunctionDeclarationInstantiation(F, argumentsList).
[...]
9.2.12 FunctionDeclarationInstantiation(func, argumentsList)
[...]
23. Let iteratorRecord be Record {[[iterator]]:
CreateListIterator(argumentsList), [[done]]: false}.
24. If hasDuplicates is true, then
[...]
25. Else,
b. Let formalStatus be IteratorBindingInitialization for formals with
iteratorRecord and env as arguments.
[...]
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;
ref = function*(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).next();
assert.sameValue(callCount, 1, 'generator function invoked exactly once');
reportCompare(0, 0);