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Configuration error
Configuration error
; | |
var GetIntrinsic = require('get-intrinsic'); | |
var $TypeError = GetIntrinsic('%TypeError%'); | |
var Call = require('./Call'); | |
var CompletionRecord = require('./CompletionRecord'); | |
var GetMethod = require('./GetMethod'); | |
var IsCallable = require('./IsCallable'); | |
var Type = require('./Type'); | |
// https://262.ecma-international.org/6.0/#sec-iteratorclose | |
module.exports = function IteratorClose(iterator, completion) { | |
if (Type(iterator) !== 'Object') { | |
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 (Type(innerResult) !== 'Object') { | |
throw new $TypeError('iterator .return must return an object'); | |
} | |
return completionRecord; | |
}; | |