Ben Murdoch | 4a90d5f | 2016-03-22 12:00:34 +0000 | [diff] [blame] | 1 | // Copyright 2014 the V8 project authors. All rights reserved. |
| 2 | // Use of this source code is governed by a BSD-style license that can be |
| 3 | // found in the LICENSE file. |
| 4 | |
| 5 | (function(global, utils) { |
| 6 | |
| 7 | "use strict"; |
| 8 | |
| 9 | %CheckIsBootstrapping(); |
| 10 | |
| 11 | // ------------------------------------------------------------------- |
| 12 | // Imports |
| 13 | |
| 14 | var GlobalString = global.String; |
| 15 | var IteratorPrototype = utils.ImportNow("IteratorPrototype"); |
| 16 | var iteratorSymbol = utils.ImportNow("iterator_symbol"); |
| 17 | var MakeTypeError; |
| 18 | var stringIteratorIteratedStringSymbol = |
| 19 | utils.ImportNow("string_iterator_iterated_string_symbol"); |
| 20 | var stringIteratorNextIndexSymbol = |
| 21 | utils.ImportNow("string_iterator_next_index_symbol"); |
| 22 | var toStringTagSymbol = utils.ImportNow("to_string_tag_symbol"); |
| 23 | |
| 24 | utils.Import(function(from) { |
| 25 | MakeTypeError = from.MakeTypeError; |
| 26 | }); |
| 27 | |
| 28 | // ------------------------------------------------------------------- |
| 29 | |
| 30 | function StringIterator() {} |
| 31 | |
| 32 | |
| 33 | // 21.1.5.1 CreateStringIterator Abstract Operation |
| 34 | function CreateStringIterator(string) { |
Ben Murdoch | da12d29 | 2016-06-02 14:46:10 +0100 | [diff] [blame] | 35 | CHECK_OBJECT_COERCIBLE(string, 'String.prototype[Symbol.iterator]'); |
Ben Murdoch | 4a90d5f | 2016-03-22 12:00:34 +0000 | [diff] [blame] | 36 | var s = TO_STRING(string); |
| 37 | var iterator = new StringIterator; |
| 38 | SET_PRIVATE(iterator, stringIteratorIteratedStringSymbol, s); |
| 39 | SET_PRIVATE(iterator, stringIteratorNextIndexSymbol, 0); |
| 40 | return iterator; |
| 41 | } |
| 42 | |
| 43 | |
| 44 | // ES6 section 21.1.5.2.1 %StringIteratorPrototype%.next ( ) |
| 45 | function StringIteratorNext() { |
| 46 | var iterator = this; |
| 47 | var value = UNDEFINED; |
| 48 | var done = true; |
| 49 | |
| 50 | if (!IS_RECEIVER(iterator) || |
| 51 | !HAS_DEFINED_PRIVATE(iterator, stringIteratorNextIndexSymbol)) { |
| 52 | throw MakeTypeError(kIncompatibleMethodReceiver, |
| 53 | 'String Iterator.prototype.next'); |
| 54 | } |
| 55 | |
| 56 | var s = GET_PRIVATE(iterator, stringIteratorIteratedStringSymbol); |
| 57 | if (!IS_UNDEFINED(s)) { |
| 58 | var position = GET_PRIVATE(iterator, stringIteratorNextIndexSymbol); |
| 59 | var length = TO_UINT32(s.length); |
| 60 | if (position >= length) { |
| 61 | SET_PRIVATE(iterator, stringIteratorIteratedStringSymbol, UNDEFINED); |
| 62 | } else { |
| 63 | var first = %_StringCharCodeAt(s, position); |
| 64 | value = %_StringCharFromCode(first); |
| 65 | done = false; |
| 66 | position++; |
| 67 | |
| 68 | if (first >= 0xD800 && first <= 0xDBFF && position < length) { |
| 69 | var second = %_StringCharCodeAt(s, position); |
| 70 | if (second >= 0xDC00 && second <= 0xDFFF) { |
| 71 | value += %_StringCharFromCode(second); |
| 72 | position++; |
| 73 | } |
| 74 | } |
| 75 | |
| 76 | SET_PRIVATE(iterator, stringIteratorNextIndexSymbol, position); |
| 77 | } |
| 78 | } |
| 79 | return %_CreateIterResultObject(value, done); |
| 80 | } |
| 81 | |
| 82 | |
| 83 | // 21.1.3.27 String.prototype [ @@iterator ]( ) |
| 84 | function StringPrototypeIterator() { |
| 85 | return CreateStringIterator(this); |
| 86 | } |
| 87 | |
| 88 | //------------------------------------------------------------------- |
| 89 | |
| 90 | %FunctionSetPrototype(StringIterator, {__proto__: IteratorPrototype}); |
| 91 | %FunctionSetInstanceClassName(StringIterator, 'String Iterator'); |
| 92 | |
| 93 | utils.InstallFunctions(StringIterator.prototype, DONT_ENUM, [ |
| 94 | 'next', StringIteratorNext |
| 95 | ]); |
| 96 | %AddNamedProperty(StringIterator.prototype, toStringTagSymbol, |
| 97 | "String Iterator", READ_ONLY | DONT_ENUM); |
| 98 | |
| 99 | utils.SetFunctionName(StringPrototypeIterator, iteratorSymbol); |
| 100 | %AddNamedProperty(GlobalString.prototype, iteratorSymbol, |
| 101 | StringPrototypeIterator, DONT_ENUM); |
| 102 | |
| 103 | }) |