tor-browser

The Tor Browser
git clone https://git.dasho.dev/tor-browser.git
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ary-ptrn-elem-id-init-skipped.js (2033B)

      1 // This file was procedurally generated from the following sources:
      2 // - src/dstr-binding/ary-ptrn-elem-id-init-skipped.case
      3 // - src/dstr-binding/default/arrow-function.template
      4 /*---
      5 description: Destructuring initializer is not evaluated when value is not `undefined` (arrow function expression)
      6 esid: sec-arrow-function-definitions-runtime-semantics-evaluation
      7 features: [destructuring-binding]
      8 flags: [generated]
      9 info: |
     10    ArrowFunction : ArrowParameters => ConciseBody
     11 
     12    [...]
     13    4. Let closure be FunctionCreate(Arrow, parameters, ConciseBody, scope, strict).
     14    [...]
     15 
     16    9.2.1 [[Call]] ( thisArgument, argumentsList)
     17 
     18    [...]
     19    7. Let result be OrdinaryCallEvaluateBody(F, argumentsList).
     20    [...]
     21 
     22    9.2.1.3 OrdinaryCallEvaluateBody ( F, argumentsList )
     23 
     24    1. Let status be FunctionDeclarationInstantiation(F, argumentsList).
     25    [...]
     26 
     27    9.2.12 FunctionDeclarationInstantiation(func, argumentsList)
     28 
     29    [...]
     30    23. Let iteratorRecord be Record {[[iterator]]:
     31        CreateListIterator(argumentsList), [[done]]: false}.
     32    24. If hasDuplicates is true, then
     33        [...]
     34    25. Else,
     35        b. Let formalStatus be IteratorBindingInitialization for formals with
     36           iteratorRecord and env as arguments.
     37    [...]
     38 
     39    13.3.3.6 Runtime Semantics: IteratorBindingInitialization
     40 
     41    SingleNameBinding : BindingIdentifier Initializeropt
     42 
     43    [...]
     44    6. If Initializer is present and v is undefined, then
     45       [...]
     46    7. If environment is undefined, return PutValue(lhs, v).
     47    8. Return InitializeReferencedBinding(lhs, v).
     48 ---*/
     49 var initCount = 0;
     50 function counter() {
     51  initCount += 1;
     52 }
     53 
     54 var callCount = 0;
     55 var f;
     56 f = ([w = counter(), x = counter(), y = counter(), z = counter()]) => {
     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([null, 0, false, '']);
     66 assert.sameValue(callCount, 1, 'arrow function invoked exactly once');
     67 
     68 reportCompare(0, 0);