Constnium/node_modules/es-abstract/2020/IteratorClose.js
2022-06-23 02:27:43 +02:00

50 lines
1.4 KiB
JavaScript

'use strict';
var GetIntrinsic = require('get-intrinsic');
var $TypeError = GetIntrinsic('%TypeError%');
var Call = require('./Call');
var GetMethod = require('./GetMethod');
var IsCallable = require('./IsCallable');
var Type = require('./Type');
// https://ecma-international.org/ecma-262/6.0/#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)) {
throw new $TypeError('Assertion failed: completion is not a thunk for a Completion Record');
}
var completionThunk = 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;
};