| // Copyright 2014 the V8 project authors. All rights reserved. |
| // Use of this source code is governed by a BSD-style license that can be |
| // found in the LICENSE file. |
| |
| (function(global, utils) { |
| |
| "use strict"; |
| |
| %CheckIsBootstrapping(); |
| |
| // ------------------------------------------------------------------- |
| // Imports |
| |
| var GlobalString = global.String; |
| var IteratorPrototype = utils.ImportNow("IteratorPrototype"); |
| var iteratorSymbol = utils.ImportNow("iterator_symbol"); |
| var MakeTypeError; |
| var stringIteratorIteratedStringSymbol = |
| utils.ImportNow("string_iterator_iterated_string_symbol"); |
| var stringIteratorNextIndexSymbol = |
| utils.ImportNow("string_iterator_next_index_symbol"); |
| var toStringTagSymbol = utils.ImportNow("to_string_tag_symbol"); |
| |
| utils.Import(function(from) { |
| MakeTypeError = from.MakeTypeError; |
| }); |
| |
| // ------------------------------------------------------------------- |
| |
| function StringIterator() {} |
| |
| |
| // 21.1.5.1 CreateStringIterator Abstract Operation |
| function CreateStringIterator(string) { |
| var s = TO_STRING(string); |
| var iterator = new StringIterator; |
| SET_PRIVATE(iterator, stringIteratorIteratedStringSymbol, s); |
| SET_PRIVATE(iterator, stringIteratorNextIndexSymbol, 0); |
| return iterator; |
| } |
| |
| |
| // ES6 section 21.1.5.2.1 %StringIteratorPrototype%.next ( ) |
| function StringIteratorNext() { |
| var iterator = this; |
| var value = UNDEFINED; |
| var done = true; |
| |
| if (!IS_RECEIVER(iterator) || |
| !HAS_DEFINED_PRIVATE(iterator, stringIteratorNextIndexSymbol)) { |
| throw MakeTypeError(kIncompatibleMethodReceiver, |
| 'String Iterator.prototype.next'); |
| } |
| |
| var s = GET_PRIVATE(iterator, stringIteratorIteratedStringSymbol); |
| if (!IS_UNDEFINED(s)) { |
| var position = GET_PRIVATE(iterator, stringIteratorNextIndexSymbol); |
| var length = TO_UINT32(s.length); |
| if (position >= length) { |
| SET_PRIVATE(iterator, stringIteratorIteratedStringSymbol, UNDEFINED); |
| } else { |
| var first = %_StringCharCodeAt(s, position); |
| value = %_StringCharFromCode(first); |
| done = false; |
| position++; |
| |
| if (first >= 0xD800 && first <= 0xDBFF && position < length) { |
| var second = %_StringCharCodeAt(s, position); |
| if (second >= 0xDC00 && second <= 0xDFFF) { |
| value += %_StringCharFromCode(second); |
| position++; |
| } |
| } |
| |
| SET_PRIVATE(iterator, stringIteratorNextIndexSymbol, position); |
| } |
| } |
| return %_CreateIterResultObject(value, done); |
| } |
| |
| |
| // 21.1.3.27 String.prototype [ @@iterator ]( ) |
| function StringPrototypeIterator() { |
| return CreateStringIterator(this); |
| } |
| |
| //------------------------------------------------------------------- |
| |
| %FunctionSetPrototype(StringIterator, {__proto__: IteratorPrototype}); |
| %FunctionSetInstanceClassName(StringIterator, 'String Iterator'); |
| |
| utils.InstallFunctions(StringIterator.prototype, DONT_ENUM, [ |
| 'next', StringIteratorNext |
| ]); |
| %AddNamedProperty(StringIterator.prototype, toStringTagSymbol, |
| "String Iterator", READ_ONLY | DONT_ENUM); |
| |
| utils.SetFunctionName(StringPrototypeIterator, iteratorSymbol); |
| %AddNamedProperty(GlobalString.prototype, iteratorSymbol, |
| StringPrototypeIterator, DONT_ENUM); |
| |
| }) |