// This file was procedurally generated from the following sources: // - src/dstr-binding/ary-ptrn-elem-id-init-undef.case // - src/dstr-binding/default/func-decl-dflt.template /*--- description: Destructuring initializer with an undefined value (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 a. Let defaultValue be the result of evaluating Initializer. b. Let v be GetValue(defaultValue). [...] 7. If environment is undefined, return PutValue(lhs, v). 8. Return InitializeReferencedBinding(lhs, v). ---*/ var callCount = 0; function f([x = 23] = [undefined]) { assert.sameValue(x, 23); callCount = callCount + 1; }; f(); assert.sameValue(callCount, 1, 'function invoked exactly once');