JSTests/test262/test/language/statements/for-of/dstr-let-ary-ptrn-elem-id-init-undef.js

// This file was procedurally generated from the following sources:
// - src/dstr-binding/ary-ptrn-elem-id-init-undef.case
// - src/dstr-binding/default/for-of-let.template
/*---
description: Destructuring initializer with an undefined value (for-of statement)
esid: sec-for-in-and-for-of-statements-runtime-semantics-labelledevaluation
es6id: 13.7.5.11
features: [destructuring-binding]
flags: [generated]
info: |
    IterationStatement :
        for ( ForDeclaration of AssignmentExpression ) Statement

    [...]
    3. Return ForIn/OfBodyEvaluation(ForDeclaration, Statement, keyResult,
       lexicalBinding, labelSet).

    13.7.5.13 Runtime Semantics: ForIn/OfBodyEvaluation

    [...]
    3. Let destructuring be IsDestructuring of lhs.
    [...]
    5. Repeat
       [...]
       h. If destructuring is false, then
          [...]
       i. Else
          i. If lhsKind is assignment, then
             [...]
          ii. Else if lhsKind is varBinding, then
              [...]
          iii. Else,
               1. Assert: lhsKind is lexicalBinding.
               2. Assert: lhs is a ForDeclaration.
               3. Let status be the result of performing BindingInitialization
                  for lhs passing nextValue and iterationEnv 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 iterCount = 0;

for (let [x = 23] of [[undefined]]) {
  assert.sameValue(x, 23);

  iterCount += 1;
}

assert.sameValue(iterCount, 1, 'Iteration occurred as expected');