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// This file was procedurally generated from the following sources:
// - src/dstr-binding/ary-ptrn-elem-id-init-skipped.case
// - src/dstr-binding/default/func-expr.template
/*---
description: Destructuring initializer is not evaluated when value is not `undefined` (function expression)
esid: sec-function-definitions-runtime-semantics-evaluation
features: [destructuring-binding]
flags: [generated]
info: |
FunctionExpression : function ( FormalParameters ) { FunctionBody }
[...]
3. Let closure be FunctionCreate(Normal, FormalParameters, FunctionBody,
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.
[...]
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;
var f;
f = function([w = counter(), x = counter(), y = counter(), z = counter()]) {
assert.sameValue(w, null);
assert.sameValue(x, 0);
assert.sameValue(y, false);
assert.sameValue(z, '');
assert.sameValue(initCount, 0);
callCount = callCount + 1;
};
f([null, 0, false, '']);
assert.sameValue(callCount, 1, 'function invoked exactly once');
reportCompare(0, 0);