| // 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 : |
| [ AssignmentElementList , Elisionopt AssignmentRestElementopt ] |
| |
| [...] |
| 3. Let iteratorRecord be Record {[[iterator]]: iterator, [[done]]: false}. |
| 4. Let status be the result of performing |
| IteratorDestructuringAssignmentEvaluation of AssignmentElementList using |
| iteratorRecord as the argument. |
| 5. If status is an abrupt completion, then |
| a. If iteratorRecord.[[done]] is false, return IteratorClose(iterator, |
| status). |
| b. Return Completion(status). |
| |
| 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 x; |
| 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 |
| [ x , ] |
| //- vals |
| iterable |