优化

‘liusuyi’

2023-10-21 ae92b6823499cfab77201b4033922fa373fb37a3

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'use strict';
 
var GetIntrinsic = require('get-intrinsic');
 
var $SyntaxError = GetIntrinsic('%SyntaxError%');
var $TypeError = GetIntrinsic('%TypeError%');
var $Promise = GetIntrinsic('%Promise%', true);
 
var Call = require('./Call');
var CompletionRecord = require('./CompletionRecord');
var GetMethod = require('./GetMethod');
var Type = require('./Type');
 
var assertRecord = require('../helpers/assertRecord');
 
var callBound = require('call-bind/callBound');
 
var $then = callBound('Promise.prototype.then', true);
 
// https://262.ecma-international.org/9.0/#sec-asynciteratorclose
 
module.exports = function AsyncIteratorClose(iteratorRecord, completion) {
    assertRecord(Type, 'Iterator Record', 'iteratorRecord', iteratorRecord); // step 1
 
    if (!(completion instanceof CompletionRecord)) {
        throw new $TypeError('Assertion failed: completion is not a Completion Record instance'); // step 2
    }
 
    if (!$then) {
        throw new $SyntaxError('This environment does not support Promises.');
    }
 
    var iterator = iteratorRecord['[[Iterator]]']; // step 3
 
    return new $Promise(function (resolve) {
        var ret = GetMethod(iterator, 'return'); // step 4
 
        if (typeof ret === 'undefined') {
            resolve(completion); // step 5
        } else {
            resolve($then(
                new $Promise(function (resolve2) {
                    // process.exit(42);
                    resolve2(Call(ret, iterator, [])); // step 6
                }),
                function (innerResult) {
                    if (Type(innerResult) !== 'Object') {
                        throw new $TypeError('`innerResult` must be an Object'); // step 10
                    }
                    return completion;
                },
                function (e) {
                    if (completion.type() === 'throw') {
                        completion['?'](); // step 8
                    } else {
                        throw e; // step 9
                    }
                }
            ));
        }
    });
};