63 lines
2.1 KiB
JavaScript
63 lines
2.1 KiB
JavaScript
|
'use strict';
|
||
|
|
|
||
|
|
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');
|
||
|
|
|
||
|
|
var assertRecord = require('../helpers/assertRecord');
|
||
|
|
|
||
|
|
// https://262.ecma-international.org/14.0/#sec-iteratorclose
|
||
|
|
|
||
|
|
module.exports = function IteratorClose(iteratorRecord, completion) {
|
||
|
|
assertRecord(Type, 'Iterator Record', 'iteratorRecord', iteratorRecord);
|
||
|
|
if (Type(iteratorRecord['[[Iterator]]']) !== 'Object') {
|
||
|
|
throw new $TypeError('Assertion failed: iteratorRecord.[[Iterator]] must be an Object'); // step 1
|
||
|
|
}
|
||
|
|
|
||
|
|
if (!IsCallable(completion) && !(completion instanceof CompletionRecord)) { // step 2
|
||
|
|
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 iterator = iteratorRecord['[[Iterator]]']; // step 3
|
||
|
|
|
||
|
|
var iteratorReturn;
|
||
|
|
try {
|
||
|
|
iteratorReturn = GetMethod(iterator, 'return'); // step 4
|
||
|
|
} catch (e) {
|
||
|
|
completionThunk(); // throws if `completion` is a throw completion // step 6
|
||
|
|
completionThunk = null; // ensure it's not called twice.
|
||
|
|
throw e; // step 7
|
||
|
|
}
|
||
|
|
if (typeof iteratorReturn === 'undefined') {
|
||
|
|
return completionThunk(); // step 5.a - 5.b
|
||
|
|
}
|
||
|
|
|
||
|
|
var innerResult;
|
||
|
|
try {
|
||
|
|
innerResult = Call(iteratorReturn, iterator, []);
|
||
|
|
} catch (e) {
|
||
|
|
// if we hit here, then "e" is the innerResult completion that needs re-throwing
|
||
|
|
|
||
|
|
completionThunk(); // throws if `completion` is a throw completion // step 6
|
||
|
|
completionThunk = null; // ensure it's not called twice.
|
||
|
|
|
||
|
|
// if not, then return the innerResult completion
|
||
|
|
throw e; // step 7
|
||
|
|
}
|
||
|
|
var 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;
|
||
|
|
};
|