dflt-obj-ptrn-id-init-skipped.js (2021B)
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-expr-dflt.template 4 /*--- 5 description: Destructuring initializer is not evaluated when value is not `undefined` (function expression (default parameter)) 6 esid: sec-function-definitions-runtime-semantics-evaluation 7 features: [destructuring-binding, default-parameters] 8 flags: [generated] 9 info: | 10 FunctionExpression : function ( FormalParameters ) { FunctionBody } 11 12 [...] 13 3. Let closure be FunctionCreate(Normal, FormalParameters, FunctionBody, 14 scope, strict). 15 [...] 16 17 9.2.1 [[Call]] ( thisArgument, argumentsList) 18 19 [...] 20 7. Let result be OrdinaryCallEvaluateBody(F, argumentsList). 21 [...] 22 23 9.2.1.3 OrdinaryCallEvaluateBody ( F, argumentsList ) 24 25 1. Let status be FunctionDeclarationInstantiation(F, argumentsList). 26 [...] 27 28 9.2.12 FunctionDeclarationInstantiation(func, argumentsList) 29 30 [...] 31 23. Let iteratorRecord be Record {[[iterator]]: 32 CreateListIterator(argumentsList), [[done]]: false}. 33 24. If hasDuplicates is true, then 34 [...] 35 25. Else, 36 b. Let formalStatus be IteratorBindingInitialization for formals with 37 iteratorRecord and env as arguments. 38 [...] 39 40 13.3.3.7 Runtime Semantics: KeyedBindingInitialization 41 42 SingleNameBinding : BindingIdentifier Initializeropt 43 44 [...] 45 6. If Initializer is present and v is undefined, then 46 [...] 47 [...] 48 ---*/ 49 var initCount = 0; 50 function counter() { 51 initCount += 1; 52 } 53 54 var callCount = 0; 55 var f; 56 f = function({ 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 65 f(); 66 assert.sameValue(callCount, 1, 'function invoked exactly once'); 67 68 reportCompare(0, 0);