'use strict';
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var GetIntrinsic = require('get-intrinsic');
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var $SyntaxError = require('es-errors/syntax');
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var $TypeError = require('es-errors/type');
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var $Promise = GetIntrinsic('%Promise%', true);
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var Call = require('./Call');
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var CreateIterResultObject = require('./CreateIterResultObject');
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var Get = require('./Get');
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var GetMethod = require('./GetMethod');
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var IteratorComplete = require('./IteratorComplete');
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var IteratorNext = require('./IteratorNext');
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var IteratorValue = require('./IteratorValue');
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var ObjectCreate = require('./ObjectCreate');
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var PromiseResolve = require('./PromiseResolve');
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var Type = require('./Type');
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var isIteratorRecord = require('../helpers/records/iterator-record');
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var SLOT = require('internal-slot');
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var callBound = require('call-bind/callBound');
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var $then = callBound('Promise.prototype.then', true);
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var AsyncFromSyncIteratorContinuation = function AsyncFromSyncIteratorContinuation(result) {
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if (Type(result) !== 'Object') {
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throw new $TypeError('Assertion failed: Type(O) is not Object');
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}
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if (arguments.length > 1) {
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throw new $TypeError('although AsyncFromSyncIteratorContinuation should take a second argument, it is not used in this implementation');
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}
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if (!$Promise) {
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throw new $SyntaxError('This environment does not support Promises.');
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}
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return new $Promise(function (resolve) {
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var done = IteratorComplete(result); // step 2
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var value = IteratorValue(result); // step 4
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var valueWrapper = PromiseResolve($Promise, value); // step 6
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// eslint-disable-next-line no-shadow
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var onFulfilled = function (value) { // steps 8-9
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return CreateIterResultObject(value, done); // step 8.a
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};
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resolve($then(valueWrapper, onFulfilled)); // step 11
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}); // step 12
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};
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var $AsyncFromSyncIteratorPrototype = GetIntrinsic('%AsyncFromSyncIteratorPrototype%', true) || {
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next: function next(value) {
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if (!$Promise) {
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throw new $SyntaxError('This environment does not support Promises.');
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}
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var O = this; // step 1
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SLOT.assert(O, '[[SyncIteratorRecord]]'); // step 2
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var argsLength = arguments.length;
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return new $Promise(function (resolve) { // step 3
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var syncIteratorRecord = SLOT.get(O, '[[SyncIteratorRecord]]'); // step 4
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var result;
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if (argsLength > 0) {
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result = IteratorNext(syncIteratorRecord['[[Iterator]]'], value); // step 5.a
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} else { // step 6
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result = IteratorNext(syncIteratorRecord['[[Iterator]]']);// step 6.a
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}
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resolve(AsyncFromSyncIteratorContinuation(result)); // step 8
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});
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},
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'return': function () {
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if (!$Promise) {
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throw new $SyntaxError('This environment does not support Promises.');
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}
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var O = this; // step 1
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SLOT.assert(O, '[[SyncIteratorRecord]]'); // step 2
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var valueIsPresent = arguments.length > 0;
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var value = valueIsPresent ? arguments[0] : void undefined;
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return new $Promise(function (resolve, reject) { // step 3
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var syncIterator = SLOT.get(O, '[[SyncIteratorRecord]]')['[[Iterator]]']; // step 4
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var iteratorReturn = GetMethod(syncIterator, 'return'); // step 5
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if (typeof iteratorReturn === 'undefined') { // step 7
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var iterResult = CreateIterResultObject(value, true); // step 7.a
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Call(resolve, undefined, [iterResult]); // step 7.b
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return;
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}
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var result;
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if (valueIsPresent) { // step 8
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result = Call(iteratorReturn, syncIterator, [value]); // step 8.a
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} else { // step 9
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result = Call(iteratorReturn, syncIterator); // step 9.a
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}
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if (Type(result) !== 'Object') { // step 11
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Call(reject, undefined, [new $TypeError('Iterator `return` method returned a non-object value.')]); // step 11.a
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return;
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}
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resolve(AsyncFromSyncIteratorContinuation(result)); // step 12
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});
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},
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'throw': function () {
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if (!$Promise) {
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throw new $SyntaxError('This environment does not support Promises.');
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}
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var O = this; // step 1
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SLOT.assert(O, '[[SyncIteratorRecord]]'); // step 2
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var valueIsPresent = arguments.length > 0;
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var value = valueIsPresent ? arguments[0] : void undefined;
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return new $Promise(function (resolve, reject) { // step 3
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var syncIterator = SLOT.get(O, '[[SyncIteratorRecord]]')['[[Iterator]]']; // step 4
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var throwMethod = GetMethod(syncIterator, 'throw'); // step 5
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if (typeof throwMethod === 'undefined') { // step 7
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Call(reject, undefined, [value]); // step 7.a
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return;
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}
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var result;
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if (valueIsPresent) { // step 8
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result = Call(throwMethod, syncIterator, [value]); // step 8.a
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} else { // step 9
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result = Call(throwMethod, syncIterator); // step 9.a
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}
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if (Type(result) !== 'Object') { // step 11
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Call(reject, undefined, [new $TypeError('Iterator `throw` method returned a non-object value.')]); // step 11.a
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return;
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}
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resolve(AsyncFromSyncIteratorContinuation(result/* , promiseCapability */)); // step 12
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});
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}
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};
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// https://262.ecma-international.org/9.0/#sec-createasyncfromsynciterator
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module.exports = function CreateAsyncFromSyncIterator(syncIteratorRecord) {
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if (!isIteratorRecord(syncIteratorRecord)) {
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throw new $TypeError('Assertion failed: `syncIteratorRecord` is not an Iterator Record');
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}
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// var asyncIterator = ObjectCreate(%AsyncFromSyncIteratorPrototype%, « [[SyncIteratorRecord]] »); // step 1
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var asyncIterator = ObjectCreate($AsyncFromSyncIteratorPrototype);
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SLOT.set(asyncIterator, '[[SyncIteratorRecord]]', syncIteratorRecord); // step 2
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var nextMethod = Get(asyncIterator, 'next'); // step 3
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return { // steps 3-4
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'[[Iterator]]': asyncIterator,
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'[[NextMethod]]': nextMethod,
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'[[Done]]': false
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};
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};
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