test262/test/language/statements/for-await-of/async-gen-dstr-var-obj-ptrn-prop-obj-init.js

// This file was procedurally generated from the following sources:
// - src/dstr-binding/obj-ptrn-prop-obj-init.case
// - src/dstr-binding/default/for-await-of-async-gen-var.template
/*---
description: Object binding pattern with "nested" object binding pattern using initializer (for-await-of statement)
esid: sec-for-in-and-for-of-statements-runtime-semantics-labelledevaluation
features: [destructuring-binding, async-iteration]
flags: [generated, async]
info: |
    IterationStatement :
        for await ( var ForBinding of AssignmentExpression ) Statement

    [...]
    2. Return ? ForIn/OfBodyEvaluation(ForBinding, Statement, keyResult,
        varBinding, 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
              1. Assert: lhs is a ForBinding.
              2. Let status be the result of performing BindingInitialization
                 for lhs passing nextValue and undefined as the arguments.
          [...]

    13.3.3.7 Runtime Semantics: KeyedBindingInitialization

    [...]
    3. If Initializer is present and v is undefined, then
       a. Let defaultValue be the result of evaluating Initializer.
       b. Let v be GetValue(defaultValue).
       c. ReturnIfAbrupt(v).
    4. Return the result of performing BindingInitialization for BindingPattern
       passing v and environment as arguments.
---*/

var iterCount = 0;

async function *fn() {
  for await (var { w: { x, y, z } = { x: 4, y: 5, z: 6 } } of [{ w: undefined }]) {
    assert.sameValue(x, 4);
    assert.sameValue(y, 5);
    assert.sameValue(z, 6);

    assert.throws(ReferenceError, function() {
      w;
    });

    iterCount += 1;
  }
}

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