source: imaps-frontend/node_modules/es-abstract/2021/CreateAsyncFromSyncIterator.js

main
Last change on this file was d565449, checked in by stefan toskovski <stefantoska84@…>, 4 weeks ago

Update repo after prototype presentation

  • Property mode set to 100644
File size: 4.5 KB
Line 
1'use strict';
2
3var GetIntrinsic = require('get-intrinsic');
4
5var $SyntaxError = require('es-errors/syntax');
6var $TypeError = require('es-errors/type');
7var $Promise = GetIntrinsic('%Promise%', true);
8
9var AsyncFromSyncIteratorContinuation = require('./AsyncFromSyncIteratorContinuation');
10var Call = require('./Call');
11var CreateIterResultObject = require('./CreateIterResultObject');
12var Get = require('./Get');
13var GetMethod = require('./GetMethod');
14var IteratorNext = require('./IteratorNext');
15var OrdinaryObjectCreate = require('./OrdinaryObjectCreate');
16var Type = require('./Type');
17
18var isIteratorRecord = require('../helpers/records/iterator-record');
19
20var SLOT = require('internal-slot');
21
22var $AsyncFromSyncIteratorPrototype = GetIntrinsic('%AsyncFromSyncIteratorPrototype%', true) || {
23 next: function next(value) {
24 if (!$Promise) {
25 throw new $SyntaxError('This environment does not support Promises.');
26 }
27
28 var O = this; // step 1
29
30 SLOT.assert(O, '[[SyncIteratorRecord]]'); // step 2
31
32 var argsLength = arguments.length;
33
34 return new $Promise(function (resolve) { // step 3
35 var syncIteratorRecord = SLOT.get(O, '[[SyncIteratorRecord]]'); // step 4
36 var result;
37 if (argsLength > 0) {
38 result = IteratorNext(syncIteratorRecord['[[Iterator]]'], value); // step 5.a
39 } else { // step 6
40 result = IteratorNext(syncIteratorRecord['[[Iterator]]']);// step 6.a
41 }
42 resolve(AsyncFromSyncIteratorContinuation(result)); // step 8
43 });
44 },
45 'return': function () {
46 if (!$Promise) {
47 throw new $SyntaxError('This environment does not support Promises.');
48 }
49
50 var O = this; // step 1
51
52 SLOT.assert(O, '[[SyncIteratorRecord]]'); // step 2
53
54 var valueIsPresent = arguments.length > 0;
55 var value = valueIsPresent ? arguments[0] : void undefined;
56
57 return new $Promise(function (resolve, reject) { // step 3
58 var syncIterator = SLOT.get(O, '[[SyncIteratorRecord]]')['[[Iterator]]']; // step 4
59 var iteratorReturn = GetMethod(syncIterator, 'return'); // step 5
60
61 if (typeof iteratorReturn === 'undefined') { // step 7
62 var iterResult = CreateIterResultObject(value, true); // step 7.a
63 Call(resolve, undefined, [iterResult]); // step 7.b
64 return;
65 }
66 var result;
67 if (valueIsPresent) { // step 8
68 result = Call(iteratorReturn, syncIterator, [value]); // step 8.a
69 } else { // step 9
70 result = Call(iteratorReturn, syncIterator); // step 9.a
71 }
72 if (Type(result) !== 'Object') { // step 11
73 Call(reject, undefined, [new $TypeError('Iterator `return` method returned a non-object value.')]); // step 11.a
74 return;
75 }
76
77 resolve(AsyncFromSyncIteratorContinuation(result)); // step 12
78 });
79 },
80 'throw': function () {
81 if (!$Promise) {
82 throw new $SyntaxError('This environment does not support Promises.');
83 }
84
85 var O = this; // step 1
86
87 SLOT.assert(O, '[[SyncIteratorRecord]]'); // step 2
88
89 var valueIsPresent = arguments.length > 0;
90 var value = valueIsPresent ? arguments[0] : void undefined;
91
92 return new $Promise(function (resolve, reject) { // step 3
93 var syncIterator = SLOT.get(O, '[[SyncIteratorRecord]]')['[[Iterator]]']; // step 4
94
95 var throwMethod = GetMethod(syncIterator, 'throw'); // step 5
96
97 if (typeof throwMethod === 'undefined') { // step 7
98 Call(reject, undefined, [value]); // step 7.a
99 return;
100 }
101
102 var result;
103 if (valueIsPresent) { // step 8
104 result = Call(throwMethod, syncIterator, [value]); // step 8.a
105 } else { // step 9
106 result = Call(throwMethod, syncIterator); // step 9.a
107 }
108 if (Type(result) !== 'Object') { // step 11
109 Call(reject, undefined, [new $TypeError('Iterator `throw` method returned a non-object value.')]); // step 11.a
110 return;
111 }
112
113 resolve(AsyncFromSyncIteratorContinuation(result/* , promiseCapability */)); // step 12
114 });
115 }
116};
117
118// https://262.ecma-international.org/11.0/#sec-createasyncfromsynciterator
119
120module.exports = function CreateAsyncFromSyncIterator(syncIteratorRecord) {
121 if (!isIteratorRecord(syncIteratorRecord)) {
122 throw new $TypeError('Assertion failed: `syncIteratorRecord` must be an Iterator Record');
123 }
124
125 // var asyncIterator = OrdinaryObjectCreate(%AsyncFromSyncIteratorPrototype%, « [[SyncIteratorRecord]] »); // step 1
126 var asyncIterator = OrdinaryObjectCreate($AsyncFromSyncIteratorPrototype);
127
128 SLOT.set(asyncIterator, '[[SyncIteratorRecord]]', syncIteratorRecord); // step 2
129
130 var nextMethod = Get(asyncIterator, 'next'); // step 3
131
132 return { // steps 3-4
133 '[[Iterator]]': asyncIterator,
134 '[[NextMethod]]': nextMethod,
135 '[[Done]]': false
136 };
137};
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