test/language/statements/for-await-of/dstr-const-ary-ptrn-rest-ary-elision.js

// This file was procedurally generated from the following sources:
// - src/dstr-binding/ary-ptrn-rest-ary-elision.case
// - src/dstr-binding/default/for-await-of-const.template
/*---
description: Rest element containing an elision (for-await-of statement)
esid: sec-for-in-and-for-of-statements-runtime-semantics-labelledevaluation
features: [generators, destructuring-binding, async-iteration]
flags: [generated, async]
info: |
    IterationStatement :
        for await ( ForDeclaration of AssignmentExpression ) Statement

    [...]
    2. Return ? ForIn/OfBodyEvaluation(ForDeclaration, Statement, keyResult,
        lexicalBinding, labelSet, async).

    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

    BindingRestElement : ... BindingPattern

    1. Let A be ArrayCreate(0).
    [...]
    3. Repeat
       [...]
       b. If iteratorRecord.[[done]] is true, then
          i. Return the result of performing BindingInitialization of
             BindingPattern with A and environment as the arguments.
       [...]

    13.3.3.6 Runtime Semantics: IteratorBindingInitialization

    ArrayBindingPattern : [ Elision ]

    1. Return the result of performing
       IteratorDestructuringAssignmentEvaluation of Elision with iteratorRecord
       as the argument.

    12.14.5.3 Runtime Semantics: IteratorDestructuringAssignmentEvaluation

    Elision : ,

    1. If iteratorRecord.[[done]] is false, then
       a. Let next be IteratorStep(iteratorRecord.[[iterator]]).
       b. If next is an abrupt completion, set iteratorRecord.[[done]] to true.
       c. ReturnIfAbrupt(next).
       d. If next is false, set iteratorRecord.[[done]] to true.
    2. Return NormalCompletion(empty).

---*/
var first = 0;
var second = 0;
function* g() {
  first += 1;
  yield;
  second += 1;
};

var iterCount = 0;

async function fn() {
  for await (const [...[,]] of [g()]) {
    assert.sameValue(first, 1);
    assert.sameValue(second, 1);

    iterCount += 1;
  }
}

fn()
  .then(() => assert.sameValue(iterCount, 1, 'iteration occurred as expected'), $DONE)
  .then($DONE, $DONE);