src/dstr-assignment/array-elision-iter-nrml-close-null.case

// Copyright (C) 2016 the V8 project authors. All rights reserved.
// This code is governed by the BSD license found in the LICENSE file.
/*---
desc: >
    IteratorClose throws a TypeError when `return` returns a non-Object value
info: |
    ArrayAssignmentPattern : [ Elision ]

    1. Let iterator be GetIterator(value).
    [...]
    5. If iteratorRecord.[[done]] is false, return IteratorClose(iterator,
       result).
    [...]

    7.4.6 IteratorClose( iterator, completion )

    [...]
    6. Let innerResult be Call(return, iterator, « »).
    7. If completion.[[type]] is throw, return Completion(completion).
    8. If innerResult.[[type]] is throw, return Completion(innerResult).
    9. If Type(innerResult.[[value]]) is not Object, throw a TypeError
       exception.
features: [Symbol.iterator]
template: error
esid: sec-runtime-semantics-destructuringassignmentevaluation
---*/

//- setup
var iterable = {};
var nextCount = 0;
var iterator = {
  next: function() {
    nextCount += 1;
    // Set an upper-bound to limit unnecessary iteration in non-conformant
    // implementations
    return { done: nextCount > 10 };
  },
  return: function() {
    return null;
  }
};
iterable[Symbol.iterator] = function() {
  return iterator;
};
//- error
TypeError
//- elems
[ , ]
//- vals
iterable