| 'use strict'; |
| |
| var $TypeError = require('es-errors/type'); |
| var isObject = require('es-object-atoms/isObject'); |
| |
| var Call = require('./Call'); |
| var CompletionRecord = require('./CompletionRecord'); |
| var GetMethod = require('./GetMethod'); |
| var IsCallable = require('./IsCallable'); |
| |
| // https://262.ecma-international.org/6.0/#sec-iteratorclose |
| |
| module.exports = function IteratorClose(iterator, completion) { |
| if (!isObject(iterator)) { |
| throw new $TypeError('Assertion failed: Type(iterator) is not Object'); |
| } |
| if (!IsCallable(completion) && !(completion instanceof CompletionRecord)) { |
| throw new $TypeError('Assertion failed: completion is not a thunk representing a Completion Record, nor a Completion Record instance'); |
| } |
| var completionThunk = completion instanceof CompletionRecord ? function () { return completion['?'](); } : completion; |
| |
| var iteratorReturn = GetMethod(iterator, 'return'); |
| |
| if (typeof iteratorReturn === 'undefined') { |
| return completionThunk(); |
| } |
| |
| var completionRecord; |
| try { |
| var innerResult = Call(iteratorReturn, iterator, []); |
| } catch (e) { |
| // if we hit here, then "e" is the innerResult completion that needs re-throwing |
| |
| // if the completion is of type "throw", this will throw. |
| completionThunk(); |
| completionThunk = null; // ensure it's not called twice. |
| |
| // if not, then return the innerResult completion |
| throw e; |
| } |
| completionRecord = completionThunk(); // if innerResult worked, then throw if the completion does |
| completionThunk = null; // ensure it's not called twice. |
| |
| if (!isObject(innerResult)) { |
| throw new $TypeError('iterator .return must return an object'); |
| } |
| |
| return completionRecord; |
| }; |