dflt-obj-ptrn-id-init-skipped.js (2048B)
1 // This file was procedurally generated from the following sources: 2 // - src/dstr-binding/obj-ptrn-id-init-skipped.case 3 // - src/dstr-binding/default/func-decl-dflt.template 4 /*--- 5 description: Destructuring initializer is not evaluated when value is not `undefined` (function declaration (default parameter)) 6 esid: sec-function-definitions-runtime-semantics-instantiatefunctionobject 7 features: [destructuring-binding, default-parameters] 8 flags: [generated] 9 info: | 10 FunctionDeclaration : 11 function BindingIdentifier ( FormalParameters ) { FunctionBody } 12 13 [...] 14 3. Let F be FunctionCreate(Normal, FormalParameters, FunctionBody, 15 scope, strict). 16 [...] 17 18 9.2.1 [[Call]] ( thisArgument, argumentsList) 19 20 [...] 21 7. Let result be OrdinaryCallEvaluateBody(F, argumentsList). 22 [...] 23 24 9.2.1.3 OrdinaryCallEvaluateBody ( F, argumentsList ) 25 26 1. Let status be FunctionDeclarationInstantiation(F, argumentsList). 27 [...] 28 29 9.2.12 FunctionDeclarationInstantiation(func, argumentsList) 30 31 [...] 32 23. Let iteratorRecord be Record {[[iterator]]: 33 CreateListIterator(argumentsList), [[done]]: false}. 34 24. If hasDuplicates is true, then 35 [...] 36 25. Else, 37 b. Let formalStatus be IteratorBindingInitialization for formals with 38 iteratorRecord and env as arguments. 39 [...] 40 41 13.3.3.7 Runtime Semantics: KeyedBindingInitialization 42 43 SingleNameBinding : BindingIdentifier Initializeropt 44 45 [...] 46 6. If Initializer is present and v is undefined, then 47 [...] 48 [...] 49 ---*/ 50 var initCount = 0; 51 function counter() { 52 initCount += 1; 53 } 54 55 var callCount = 0; 56 function f({ w = counter(), x = counter(), y = counter(), z = counter() } = { w: null, x: 0, y: false, z: '' }) { 57 assert.sameValue(w, null); 58 assert.sameValue(x, 0); 59 assert.sameValue(y, false); 60 assert.sameValue(z, ''); 61 assert.sameValue(initCount, 0); 62 callCount = callCount + 1; 63 }; 64 f(); 65 assert.sameValue(callCount, 1, 'function invoked exactly once'); 66 67 reportCompare(0, 0);