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