src/dstr-assignment/array-elem-iter-rtrn-close-err.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 is called when reference evaluation produces a "return"
    completion
info: |
    ArrayAssignmentPattern : [ AssignmentElementList ]

    [...]
    5. If iteratorRecord.[[done]] is false, return IteratorClose(iterator,
       result).
    6. Return 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).
features: [Symbol.iterator, generators]
template: default
esid: sec-runtime-semantics-destructuringassignmentevaluation
---*/

//- setup
var returnCount = 0;
var unreachable = 0;
var iterable = {};
var iterator = {
  return: function() {
    returnCount += 1;
    throw new Test262Error();
  }
};
var iter;
iterable[Symbol.iterator] = function() {
  return iterator;
};

function* g() {
//- elems
[ {}[ yield ] ]
//- vals
iterable
//- body
unreachable += 1;
//- teardown
}
iter = g();
iter.next();
assert.throws(Test262Error, function() {
  iter.return();
});

assert.sameValue(returnCount, 1);
assert.sameValue(unreachable, 0, 'Unreachable statement was not executed');