test262/test/language/statements/function/dstr-dflt-ary-ptrn-elem-id-...

68 lines
2.1 KiB
JavaScript

// This file was procedurally generated from the following sources:
// - src/dstr-binding/ary-ptrn-elem-id-init-skipped.case
// - src/dstr-binding/default/func-decl-dflt.template
/*---
description: Destructuring initializer is not evaluated when value is not `undefined` (function declaration (default parameter))
esid: sec-function-definitions-runtime-semantics-instantiatefunctionobject
es6id: 14.1.19
features: [destructuring-binding, default-parameters]
flags: [generated]
info: |
FunctionDeclaration :
function BindingIdentifier ( FormalParameters ) { FunctionBody }
[...]
3. Let F 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;
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();
assert.sameValue(callCount, 1, 'function invoked exactly once');