sdk/lib/_internal/js_runtime/lib/core_patch.dart - sdk.git - Git at Google

 // Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.

 // Patch file for dart:core classes.
 import "dart:_internal" as _symbol_dev;
 import 'dart:_interceptors';
 import 'dart:_js_helper' show checkInt,
                               Closure,
                               ConstantMap,
                               getRuntimeType,
                               JsLinkedHashMap,
                               jsonEncodeNative,
                               JSSyntaxRegExp,
                               NoInline,
                               objectHashCode,
                               patch,
                               patch_full,
                               patch_lazy,
                               patch_startup,
                               Primitives,
                               stringJoinUnchecked,
                               getTraceFromException,
                               RuntimeError;

 import 'dart:_foreign_helper' show JS;

 import 'dart:_native_typed_data' show NativeUint8List;

 import 'dart:async' show StreamController;

 String _symbolToString(Symbol symbol) => _symbol_dev.Symbol.getName(symbol);

 _symbolMapToStringMap(Map<Symbol, dynamic> map) {
   if (map == null) return null;
   var result = new Map<String, dynamic>();
   map.forEach((Symbol key, value) {
     result[_symbolToString(key)] = value;
   });
   return result;
 }

 @patch
 int identityHashCode(Object object) => objectHashCode(object);

 // Patch for Object implementation.
 @patch
 class Object {
   @patch
   bool operator==(other) => identical(this, other);

   @patch
   int get hashCode => Primitives.objectHashCode(this);


   @patch
   String toString() => Primitives.objectToHumanReadableString(this);

   @patch
   dynamic noSuchMethod(Invocation invocation) {
     throw new NoSuchMethodError(
         this,
         invocation.memberName,
         invocation.positionalArguments,
         invocation.namedArguments);
   }

   @patch
   Type get runtimeType => getRuntimeType(this);
 }

 @patch
 class Null {
   @patch
   int get hashCode => super.hashCode;
 }

 // Patch for Function implementation.
 @patch
 class Function {
   @patch_full
   static apply(Function function,
                List positionalArguments,
                [Map<Symbol, dynamic> namedArguments]) {
     return Primitives.applyFunction(
         function, positionalArguments,
         namedArguments == null ? null : _toMangledNames(namedArguments));
   }

   @patch_lazy
   static apply(Function function,
                List positionalArguments,
                [Map<Symbol, dynamic> namedArguments]) {
     return Primitives.applyFunction2(function, positionalArguments,
         namedArguments == null ? null : _symbolMapToStringMap(namedArguments));
   }

   @patch_startup
   static apply(Function function,
                List positionalArguments,
                [Map<Symbol, dynamic> namedArguments]) {
     return Primitives.applyFunction2(function, positionalArguments,
         namedArguments == null ? null : _symbolMapToStringMap(namedArguments));
   }

   static Map<String, dynamic> _toMangledNames(
       Map<Symbol, dynamic> namedArguments) {
     Map<String, dynamic> result = {};
     namedArguments.forEach((symbol, value) {
       result[_symbolToString(symbol)] = value;
     });
     return result;
   }
 }

 // Patch for Expando implementation.
 @patch
 class Expando<T> {
   static const String _EXPANDO_PROPERTY_NAME = 'expando\$values';

   // Incremented to make unique keys.
   static int _keyCount = 0;

   // Stores either a JS WeakMap or a "unique" string key.
   final Object _jsWeakMapOrKey;

   @patch
   Expando([String name])
       : this.name = name,
         _jsWeakMapOrKey = JS('bool', 'typeof WeakMap == "function"')
             ? JS('=Object|Null', 'new WeakMap()')
             : _createKey();

   @patch
   T operator[](Object object) {
     if (_jsWeakMapOrKey is! String) {
       _checkType(object);  // WeakMap doesn't check on reading, only writing.
       return JS('', '#.get(#)', _jsWeakMapOrKey, object);
     }
     return _getFromObject(_jsWeakMapOrKey, object);
   }

   @patch
   void operator[]=(Object object, T value) {
     if (_jsWeakMapOrKey is! String) {
       JS('void', '#.set(#, #)', _jsWeakMapOrKey, object, value);
     } else {
       _setOnObject(_jsWeakMapOrKey, object, value);
     }
   }

   static Object _getFromObject(String key, Object object) {
     var values = Primitives.getProperty(object, _EXPANDO_PROPERTY_NAME);
     return (values == null) ? null : Primitives.getProperty(values, key);
   }

   static void _setOnObject(String key, Object object, Object value) {
     var values = Primitives.getProperty(object, _EXPANDO_PROPERTY_NAME);
     if (values == null) {
       values = new Object();
       Primitives.setProperty(object, _EXPANDO_PROPERTY_NAME, values);
     }
     Primitives.setProperty(values, key, value);
   }

   static String _createKey() => "expando\$key\$${_keyCount++}";

   static _checkType(object) {
     if (object == null || object is bool || object is num || object is String) {
       throw new ArgumentError.value(object,
           "Expandos are not allowed on strings, numbers, booleans or null");
     }
   }
 }

 @patch
 class int {
   @patch
   static int parse(String source,
                          { int radix,
                            int onError(String source) }) {
     return Primitives.parseInt(source, radix, onError);
   }

   @patch
   factory int.fromEnvironment(String name, {int defaultValue}) {
     throw new UnsupportedError(
         'int.fromEnvironment can only be used as a const constructor');
   }
 }

 @patch
 class double {
   @patch
   static double parse(String source,
                             [double onError(String source)]) {
     return Primitives.parseDouble(source, onError);
   }
 }

 @patch
 class Error {
   @patch
   static String _objectToString(Object object) {
     // Closures all have useful and safe toString methods.
     if (object is Closure) return object.toString();
     return Primitives.objectToHumanReadableString(object);
   }

   @patch
   static String _stringToSafeString(String string) {
     return jsonEncodeNative(string);
   }

   @patch
   StackTrace get stackTrace => Primitives.extractStackTrace(this);
 }

 @patch
 class FallThroughError {
   @patch
   String toString() => super.toString();
 }

 @patch
 class AbstractClassInstantiationError {
   @patch
   String toString() => "Cannot instantiate abstract class: '$_className'";
 }

 // Patch for DateTime implementation.
 @patch
 class DateTime {
   @patch
   DateTime.fromMillisecondsSinceEpoch(int millisecondsSinceEpoch,
                                       {bool isUtc: false})
       : this._withValue(millisecondsSinceEpoch, isUtc: isUtc);

   @patch
   DateTime.fromMicrosecondsSinceEpoch(int microsecondsSinceEpoch,
                                       {bool isUtc: false})
       : this._withValue(
           _microsecondInRoundedMilliseconds(microsecondsSinceEpoch),
           isUtc: isUtc);

   @patch
   DateTime._internal(int year,
                      int month,
                      int day,
                      int hour,
                      int minute,
                      int second,
                      int millisecond,
                      int microsecond,
                      bool isUtc)
         // checkBool is manually inlined here because dart2js doesn't inline it
         // and [isUtc] is usually a constant.
       : this.isUtc = isUtc is bool
             ? isUtc
             : throw new ArgumentError.value(isUtc, 'isUtc'),
         _value = checkInt(Primitives.valueFromDecomposedDate(
             year, month, day, hour, minute, second,
             millisecond + _microsecondInRoundedMilliseconds(microsecond),
             isUtc));

   @patch
   DateTime._now()
       : isUtc = false,
         _value = Primitives.dateNow();

   /// Rounds the given [microsecond] to the nearest milliseconds value.
   ///
   /// For example, invoked with argument `2600` returns `3`.
   static int _microsecondInRoundedMilliseconds(int microsecond) {
     return (microsecond / 1000).round();
   }

   @patch
   static int _brokenDownDateToValue(
       int year, int month, int day, int hour, int minute, int second,
       int millisecond, int microsecond, bool isUtc) {
     return Primitives.valueFromDecomposedDate(
         year, month, day, hour, minute, second,
         millisecond + _microsecondInRoundedMilliseconds(microsecond),
         isUtc);
   }

   @patch
   String get timeZoneName {
     if (isUtc) return "UTC";
     return Primitives.getTimeZoneName(this);
   }

   @patch
   Duration get timeZoneOffset {
     if (isUtc) return new Duration();
     return new Duration(minutes: Primitives.getTimeZoneOffsetInMinutes(this));
   }

   @patch
   DateTime add(Duration duration) {
     return new DateTime._withValue(
         _value + duration.inMilliseconds, isUtc: isUtc);
   }

   @patch
   DateTime subtract(Duration duration) {
     return new DateTime._withValue(
         _value - duration.inMilliseconds, isUtc: isUtc);
   }

   @patch
   Duration difference(DateTime other) {
     return new Duration(milliseconds: _value - other._value);
   }

   @patch
   int get millisecondsSinceEpoch => _value;

   @patch
   int get microsecondsSinceEpoch => _value * 1000;

   @patch
   int get year => Primitives.getYear(this);

   @patch
   int get month => Primitives.getMonth(this);

   @patch
   int get day => Primitives.getDay(this);

   @patch
   int get hour => Primitives.getHours(this);

   @patch
   int get minute => Primitives.getMinutes(this);

   @patch
   int get second => Primitives.getSeconds(this);

   @patch
   int get millisecond => Primitives.getMilliseconds(this);

   @patch
   int get microsecond => 0;

   @patch
   int get weekday => Primitives.getWeekday(this);
 }


 // Patch for Stopwatch implementation.
 @patch
 class Stopwatch {
   @patch
   static void _initTicker() {
     Primitives.initTicker();
     _frequency = Primitives.timerFrequency;
   }

   @patch
   static int _now() => Primitives.timerTicks();
 }

 // Patch for List implementation.
 @patch
 class List<E> {
   @patch
   factory List([int length]) = JSArray<E>.list;

   @patch
   factory List.filled(int length, E fill, {bool growable: false}) {
     List result = growable ? new JSArray<E>.growable(length)
                            : new JSArray<E>.fixed(length);
     if (length != 0 && fill != null) {
       for (int i = 0; i < result.length; i++) {
         result[i] = fill;
       }
     }
     return result;
   }

   @patch
   factory List.from(Iterable elements, { bool growable: true }) {
     List<E> list = new List<E>();
     for (E e in elements) {
       list.add(e);
     }
     if (growable) return list;
     return makeListFixedLength(list);
   }

   @patch
   factory List.unmodifiable(Iterable elements) {
     List result = new List<E>.from(elements, growable: false);
     return makeFixedListUnmodifiable(result);
   }
 }

 @patch
 class Map<K, V> {
   @patch
   factory Map.unmodifiable(Map other) = ConstantMap<K, V>.from;

   @patch
   factory Map() = JsLinkedHashMap<K, V>.es6;
 }

 @patch
 class String {
   @patch
   factory String.fromCharCodes(Iterable<int> charCodes,
                                [int start = 0, int end]) {

     if (charCodes is JSArray) {
       return _stringFromJSArray(charCodes, start, end);
     }
     if (charCodes is NativeUint8List) {
       return _stringFromUint8List(charCodes, start, end);
     }
     return _stringFromIterable(charCodes, start, end);
   }

   @patch
   factory String.fromCharCode(int charCode) {
     return Primitives.stringFromCharCode(charCode);
   }

   @patch
   factory String.fromEnvironment(String name, {String defaultValue}) {
     throw new UnsupportedError(
         'String.fromEnvironment can only be used as a const constructor');
   }

   static String _stringFromJSArray(List list, int start, int endOrNull) {
     int len = list.length;
     int end = RangeError.checkValidRange(start, endOrNull, len);
     if (start > 0 || end < len) {
       list = list.sublist(start, end);
     }
     return Primitives.stringFromCharCodes(list);
   }

   static String _stringFromUint8List(
       NativeUint8List charCodes, int start, int endOrNull) {
     int len = charCodes.length;
     int end = RangeError.checkValidRange(start, endOrNull, len);
     return Primitives.stringFromNativeUint8List(charCodes, start, end);
   }

   static String _stringFromIterable(Iterable<int> charCodes,
                                     int start, int end) {
     if (start < 0) throw new RangeError.range(start, 0, charCodes.length);
     if (end != null && end < start) {
       throw new RangeError.range(end, start, charCodes.length);
     }
     var it = charCodes.iterator;
     for (int i = 0; i < start; i++) {
       if (!it.moveNext()) {
         throw new RangeError.range(start, 0, i);
       }
     }
     var list = [];
     if (end == null) {
       while (it.moveNext()) list.add(it.current);
     } else {
       for (int i = start; i < end; i++) {
         if (!it.moveNext()) {
           throw new RangeError.range(end, start, i);
         }
         list.add(it.current);
       }
     }
     return Primitives.stringFromCharCodes(list);
   }
 }

 @patch
 class bool {
   @patch
   factory bool.fromEnvironment(String name, {bool defaultValue: false}) {
     throw new UnsupportedError(
         'bool.fromEnvironment can only be used as a const constructor');
   }

   @patch
   int get hashCode => super.hashCode;
 }

 @patch
 class RegExp {
   @NoInline()
   @patch
   factory RegExp(String source,
                        {bool multiLine: false,
                         bool caseSensitive: true})
     => new JSSyntaxRegExp(source,
                           multiLine: multiLine,
                           caseSensitive: caseSensitive);
 }

 // Patch for 'identical' function.
 @NoInline() // No inlining since we recognize the call in optimizer.
 @patch
 bool identical(Object a, Object b) {
   return JS('bool', '(# == null ? # == null : # === #)', a, b, a, b);
 }

 @patch
 class StringBuffer {
   String _contents;

   @patch
   StringBuffer([Object content = ""]) : _contents = '$content';

   @patch
   int get length => _contents.length;

   @patch
   void write(Object obj) {
     _writeString('$obj');
   }

   @patch
   void writeCharCode(int charCode) {
     _writeString(new String.fromCharCode(charCode));
   }

   @patch
   void writeAll(Iterable objects, [String separator = ""]) {
     _contents = _writeAll(_contents, objects, separator);
   }

   @patch
   void writeln([Object obj = ""]) {
     _writeString('$obj\n');
   }

   @patch
   void clear() {
     _contents = "";
   }

   @patch
   String toString() => Primitives.flattenString(_contents);

   void _writeString(str) {
     _contents = Primitives.stringConcatUnchecked(_contents, str);
   }

   static String _writeAll(String string, Iterable objects, String separator) {
     Iterator iterator = objects.iterator;
     if (!iterator.moveNext()) return string;
     if (separator.isEmpty) {
       do {
         string = _writeOne(string, iterator.current);
       } while (iterator.moveNext());
     } else {
       string = _writeOne(string, iterator.current);
       while (iterator.moveNext()) {
         string = _writeOne(string, separator);
         string = _writeOne(string, iterator.current);
       }
     }
     return string;
   }

   static String _writeOne(String string, Object obj) {
     return Primitives.stringConcatUnchecked(string, '$obj');
   }
 }

 @patch
 class NoSuchMethodError {
   @patch
   NoSuchMethodError(Object receiver,
                     Symbol memberName,
                     List positionalArguments,
                     Map<Symbol, dynamic> namedArguments,
                     [List existingArgumentNames = null])
       : _receiver = receiver,
         _memberName = memberName,
         _arguments = positionalArguments,
         _namedArguments = namedArguments,
         _existingArgumentNames = existingArgumentNames;

   @patch
   String toString() {
     StringBuffer sb = new StringBuffer('');
     String comma = '';
     if (_arguments != null) {
       for (var argument in _arguments) {
         sb.write(comma);
         sb.write(Error.safeToString(argument));
         comma = ', ';
       }
     }
     if (_namedArguments != null) {
       _namedArguments.forEach((Symbol key, var value) {
         sb.write(comma);
         sb.write(_symbolToString(key));
         sb.write(": ");
         sb.write(Error.safeToString(value));
         comma = ', ';
       });
     }
     String memberName = _symbolToString(_memberName);
     String receiverText = Error.safeToString(_receiver);
     String actualParameters = '$sb';
     if (_existingArgumentNames == null) {
       return "NoSuchMethodError: method not found: '$memberName'\n"
           "Receiver: ${receiverText}\n"
           "Arguments: [$actualParameters]";
     } else {
       String formalParameters = _existingArgumentNames.join(', ');
       return "NoSuchMethodError: incorrect number of arguments passed to "
           "method named '$memberName'\n"
           "Receiver: ${receiverText}\n"
           "Tried calling: $memberName($actualParameters)\n"
           "Found: $memberName($formalParameters)";
     }
   }
 }

 @patch
 class Uri {
   @patch
   static Uri get base {
     String uri = Primitives.currentUri();
     if (uri != null) return Uri.parse(uri);
     throw new UnsupportedError("'Uri.base' is not supported");
   }
 }

 @patch
 class _Uri {
   @patch
   static bool get _isWindows => false;

   // Matches a String that _uriEncodes to itself regardless of the kind of
   // component.  This corresponds to [_unreservedTable], i.e. characters that
   // are not encoded by any encoding table.
   static final RegExp _needsNoEncoding = new RegExp(r'^[\-\.0-9A-Z_a-z~]*$');

   /**
    * This is the internal implementation of JavaScript's encodeURI function.
    * It encodes all characters in the string [text] except for those
    * that appear in [canonicalTable], and returns the escaped string.
    */
   @patch
   static String _uriEncode(List<int> canonicalTable,
                            String text,
                            Encoding encoding,
                            bool spaceToPlus) {
     if (identical(encoding, UTF8) && _needsNoEncoding.hasMatch(text)) {
       return text;
     }

     // Encode the string into bytes then generate an ASCII only string
     // by percent encoding selected bytes.
     StringBuffer result = new StringBuffer('');
     var bytes = encoding.encode(text);
     for (int i = 0; i < bytes.length; i++) {
       int byte = bytes[i];
       if (byte < 128 &&
           ((canonicalTable[byte >> 4] & (1 << (byte & 0x0f))) != 0)) {
         result.writeCharCode(byte);
       } else if (spaceToPlus && byte == _SPACE) {
         result.write('+');
       } else {
         const String hexDigits = '0123456789ABCDEF';
         result.write('%');
         result.write(hexDigits[(byte >> 4) & 0x0f]);
         result.write(hexDigits[byte & 0x0f]);
       }
     }
     return result.toString();
   }
 }

 Uri _resolvePackageUri(Uri packageUri) {
   assert(packageUri.scheme == "package");
   if (packageUri.hasAuthority) {
     throw new ArgumentError("Package-URI must not have a host: $packageUri");
   }
   var resolved = Uri.base.resolve("packages/${packageUri.path}");
   return resolved;
 }

 @patch
 class StackTrace {
   @patch
   @NoInline()
   static StackTrace get current {
     if (JS('', 'Error.captureStackTrace') != null) {
       var error = JS('', 'new Error()');
       JS('void', 'Error.captureStackTrace(#)', error);
       return getTraceFromException(error);
     }
     // Fallback if Error.captureStackTrace does not exist.
     try {
       throw '';
     } catch (_, stackTrace) {
       return stackTrace;
     }
   }
 }

 // Called from kernel generated code.
 _malformedTypeError(message) => new RuntimeError(message);

 // Called from kernel generated code.
 _genericNoSuchMethod(receiver, memberName, positionalArguments, namedArguments,
     existingArguments) {
   return new NoSuchMethodError(
       receiver,
       memberName,
       positionalArguments,
       namedArguments);
 }

 // Called from kernel generated code.
 _unresolvedConstructorError(receiver, memberName, positionalArguments,
     namedArguments, existingArguments) {
   // TODO(sra): Generate an error that reads:
   //
   //     No constructor '$memberName' declared in class '$receiver'.

   return new NoSuchMethodError(
       receiver,
       memberName,
       positionalArguments,
       namedArguments);
 }

 // Called from kernel generated code.
 _unresolvedStaticGetterError(receiver, memberName, positionalArguments,
     namedArguments, existingArguments) {
   // TODO(sra): Generate customized message.
   return new NoSuchMethodError(
       receiver,
       memberName,
       positionalArguments,
       namedArguments);
 }

 // Called from kernel generated code.
 _unresolvedStaticSetterError(receiver, memberName, positionalArguments,
     namedArguments, existingArguments) {
   // TODO(sra): Generate customized message.
   return new NoSuchMethodError(
       receiver,
       memberName,
       positionalArguments,
       namedArguments);
 }

 // Called from kernel generated code.
 _unresolvedStaticMethodError(receiver, memberName, positionalArguments,
     namedArguments, existingArguments) {
   // TODO(sra): Generate customized message.
   return new NoSuchMethodError(
       receiver,
       memberName,
       positionalArguments,
       namedArguments);
 }

 // Called from kernel generated code.
 _unresolvedTopLevelGetterError(receiver, memberName, positionalArguments,
     namedArguments, existingArguments) {
   // TODO(sra): Generate customized message.
   return new NoSuchMethodError(
       receiver,
       memberName,
       positionalArguments,
       namedArguments);
 }

 // Called from kernel generated code.
 _unresolvedTopLevelSetterError(receiver, memberName, positionalArguments,
     namedArguments, existingArguments) {
   // TODO(sra): Generate customized message.
   return new NoSuchMethodError(
       receiver,
       memberName,
       positionalArguments,
       namedArguments);
 }

 // Called from kernel generated code.
 _unresolvedTopLevelMethodError(receiver, memberName, positionalArguments,
     namedArguments, existingArguments) {
   // TODO(sra): Generate customized message.
   return new NoSuchMethodError(
       receiver,
       memberName,
       positionalArguments,
       namedArguments);
 }
	// Copyright (c) 2012, the Dart project authors. Please see the AUTHORS file
	// for details. All rights reserved. Use of this source code is governed by a
	// BSD-style license that can be found in the LICENSE file.

	// Patch file for dart:core classes.
	import "dart:_internal" as _symbol_dev;
	import 'dart:_interceptors';
	import 'dart:_js_helper' show checkInt,
	Closure,
	ConstantMap,
	getRuntimeType,
	JsLinkedHashMap,
	jsonEncodeNative,
	JSSyntaxRegExp,
	NoInline,
	objectHashCode,
	patch,
	patch_full,
	patch_lazy,
	patch_startup,
	Primitives,
	stringJoinUnchecked,
	getTraceFromException,
	RuntimeError;

	import 'dart:_foreign_helper' show JS;

	import 'dart:_native_typed_data' show NativeUint8List;

	import 'dart:async' show StreamController;

	String _symbolToString(Symbol symbol) => _symbol_dev.Symbol.getName(symbol);

	_symbolMapToStringMap(Map<Symbol, dynamic> map) {
	if (map == null) return null;
	var result = new Map<String, dynamic>();
	map.forEach((Symbol key, value) {
	result[_symbolToString(key)] = value;
	});
	return result;
	}

	@patch
	int identityHashCode(Object object) => objectHashCode(object);

	// Patch for Object implementation.
	@patch
	class Object {
	@patch
	bool operator==(other) => identical(this, other);

	@patch
	int get hashCode => Primitives.objectHashCode(this);


	@patch
	String toString() => Primitives.objectToHumanReadableString(this);

	@patch
	dynamic noSuchMethod(Invocation invocation) {
	throw new NoSuchMethodError(
	this,
	invocation.memberName,
	invocation.positionalArguments,
	invocation.namedArguments);
	}

	@patch
	Type get runtimeType => getRuntimeType(this);
	}

	@patch
	class Null {
	@patch
	int get hashCode => super.hashCode;
	}

	// Patch for Function implementation.
	@patch
	class Function {
	@patch_full
	static apply(Function function,
	List positionalArguments,
	[Map<Symbol, dynamic> namedArguments]) {
	return Primitives.applyFunction(
	function, positionalArguments,
	namedArguments == null ? null : _toMangledNames(namedArguments));
	}

	@patch_lazy
	static apply(Function function,
	List positionalArguments,
	[Map<Symbol, dynamic> namedArguments]) {
	return Primitives.applyFunction2(function, positionalArguments,
	namedArguments == null ? null : _symbolMapToStringMap(namedArguments));
	}

	@patch_startup
	static apply(Function function,
	List positionalArguments,
	[Map<Symbol, dynamic> namedArguments]) {
	return Primitives.applyFunction2(function, positionalArguments,
	namedArguments == null ? null : _symbolMapToStringMap(namedArguments));
	}

	static Map<String, dynamic> _toMangledNames(
	Map<Symbol, dynamic> namedArguments) {
	Map<String, dynamic> result = {};
	namedArguments.forEach((symbol, value) {
	result[_symbolToString(symbol)] = value;
	});
	return result;
	}
	}

	// Patch for Expando implementation.
	@patch
	class Expando<T> {
	static const String _EXPANDO_PROPERTY_NAME = 'expando\$values';

	// Incremented to make unique keys.
	static int _keyCount = 0;

	// Stores either a JS WeakMap or a "unique" string key.
	final Object _jsWeakMapOrKey;

	@patch
	Expando([String name])
	: this.name = name,
	_jsWeakMapOrKey = JS('bool', 'typeof WeakMap == "function"')
	? JS('=Object\|Null', 'new WeakMap()')
	: _createKey();

	@patch
	T operator[](Object object) {
	if (_jsWeakMapOrKey is! String) {
	_checkType(object); // WeakMap doesn't check on reading, only writing.
	return JS('', '#.get(#)', _jsWeakMapOrKey, object);
	}
	return _getFromObject(_jsWeakMapOrKey, object);
	}

	@patch
	void operator[]=(Object object, T value) {
	if (_jsWeakMapOrKey is! String) {
	JS('void', '#.set(#, #)', _jsWeakMapOrKey, object, value);
	} else {
	_setOnObject(_jsWeakMapOrKey, object, value);
	}
	}

	static Object _getFromObject(String key, Object object) {
	var values = Primitives.getProperty(object, _EXPANDO_PROPERTY_NAME);
	return (values == null) ? null : Primitives.getProperty(values, key);
	}

	static void _setOnObject(String key, Object object, Object value) {
	var values = Primitives.getProperty(object, _EXPANDO_PROPERTY_NAME);
	if (values == null) {
	values = new Object();
	Primitives.setProperty(object, _EXPANDO_PROPERTY_NAME, values);
	}
	Primitives.setProperty(values, key, value);
	}

	static String _createKey() => "expando\$key\$${_keyCount++}";

	static _checkType(object) {
	if (object == null \|\| object is bool \|\| object is num \|\| object is String) {
	throw new ArgumentError.value(object,
	"Expandos are not allowed on strings, numbers, booleans or null");
	}
	}
	}

	@patch
	class int {
	@patch
	static int parse(String source,
	{ int radix,
	int onError(String source) }) {
	return Primitives.parseInt(source, radix, onError);
	}

	@patch
	factory int.fromEnvironment(String name, {int defaultValue}) {
	throw new UnsupportedError(
	'int.fromEnvironment can only be used as a const constructor');
	}
	}

	@patch
	class double {
	@patch
	static double parse(String source,
	[double onError(String source)]) {
	return Primitives.parseDouble(source, onError);
	}
	}

	@patch
	class Error {
	@patch
	static String _objectToString(Object object) {
	// Closures all have useful and safe toString methods.
	if (object is Closure) return object.toString();
	return Primitives.objectToHumanReadableString(object);
	}

	@patch
	static String _stringToSafeString(String string) {
	return jsonEncodeNative(string);
	}

	@patch
	StackTrace get stackTrace => Primitives.extractStackTrace(this);
	}

	@patch
	class FallThroughError {
	@patch
	String toString() => super.toString();
	}

	@patch
	class AbstractClassInstantiationError {
	@patch
	String toString() => "Cannot instantiate abstract class: '$_className'";
	}

	// Patch for DateTime implementation.
	@patch
	class DateTime {
	@patch
	DateTime.fromMillisecondsSinceEpoch(int millisecondsSinceEpoch,
	{bool isUtc: false})
	: this._withValue(millisecondsSinceEpoch, isUtc: isUtc);

	@patch
	DateTime.fromMicrosecondsSinceEpoch(int microsecondsSinceEpoch,
	{bool isUtc: false})
	: this._withValue(
	_microsecondInRoundedMilliseconds(microsecondsSinceEpoch),
	isUtc: isUtc);

	@patch
	DateTime._internal(int year,
	int month,
	int day,
	int hour,
	int minute,
	int second,
	int millisecond,
	int microsecond,
	bool isUtc)
	// checkBool is manually inlined here because dart2js doesn't inline it
	// and [isUtc] is usually a constant.
	: this.isUtc = isUtc is bool
	? isUtc
	: throw new ArgumentError.value(isUtc, 'isUtc'),
	_value = checkInt(Primitives.valueFromDecomposedDate(
	year, month, day, hour, minute, second,
	millisecond + _microsecondInRoundedMilliseconds(microsecond),
	isUtc));

	@patch
	DateTime._now()
	: isUtc = false,
	_value = Primitives.dateNow();

	/// Rounds the given [microsecond] to the nearest milliseconds value.
	///
	/// For example, invoked with argument `2600` returns `3`.
	static int _microsecondInRoundedMilliseconds(int microsecond) {
	return (microsecond / 1000).round();
	}

	@patch
	static int _brokenDownDateToValue(
	int year, int month, int day, int hour, int minute, int second,
	int millisecond, int microsecond, bool isUtc) {
	return Primitives.valueFromDecomposedDate(
	year, month, day, hour, minute, second,
	millisecond + _microsecondInRoundedMilliseconds(microsecond),
	isUtc);
	}

	@patch
	String get timeZoneName {
	if (isUtc) return "UTC";
	return Primitives.getTimeZoneName(this);
	}

	@patch
	Duration get timeZoneOffset {
	if (isUtc) return new Duration();
	return new Duration(minutes: Primitives.getTimeZoneOffsetInMinutes(this));
	}

	@patch
	DateTime add(Duration duration) {
	return new DateTime._withValue(
	_value + duration.inMilliseconds, isUtc: isUtc);
	}

	@patch
	DateTime subtract(Duration duration) {
	return new DateTime._withValue(
	_value - duration.inMilliseconds, isUtc: isUtc);
	}

	@patch
	Duration difference(DateTime other) {
	return new Duration(milliseconds: _value - other._value);
	}

	@patch
	int get millisecondsSinceEpoch => _value;

	@patch
	int get microsecondsSinceEpoch => _value * 1000;

	@patch
	int get year => Primitives.getYear(this);

	@patch
	int get month => Primitives.getMonth(this);

	@patch
	int get day => Primitives.getDay(this);

	@patch
	int get hour => Primitives.getHours(this);

	@patch
	int get minute => Primitives.getMinutes(this);

	@patch
	int get second => Primitives.getSeconds(this);

	@patch
	int get millisecond => Primitives.getMilliseconds(this);

	@patch
	int get microsecond => 0;

	@patch
	int get weekday => Primitives.getWeekday(this);
	}


	// Patch for Stopwatch implementation.
	@patch
	class Stopwatch {
	@patch
	static void _initTicker() {
	Primitives.initTicker();
	_frequency = Primitives.timerFrequency;
	}

	@patch
	static int _now() => Primitives.timerTicks();
	}

	// Patch for List implementation.
	@patch
	class List<E> {
	@patch
	factory List([int length]) = JSArray<E>.list;

	@patch
	factory List.filled(int length, E fill, {bool growable: false}) {
	List result = growable ? new JSArray<E>.growable(length)
	: new JSArray<E>.fixed(length);
	if (length != 0 && fill != null) {
	for (int i = 0; i < result.length; i++) {
	result[i] = fill;
	}
	}
	return result;
	}

	@patch
	factory List.from(Iterable elements, { bool growable: true }) {
	List<E> list = new List<E>();
	for (E e in elements) {
	list.add(e);
	}
	if (growable) return list;
	return makeListFixedLength(list);
	}

	@patch
	factory List.unmodifiable(Iterable elements) {
	List result = new List<E>.from(elements, growable: false);
	return makeFixedListUnmodifiable(result);
	}
	}

	@patch
	class Map<K, V> {
	@patch
	factory Map.unmodifiable(Map other) = ConstantMap<K, V>.from;

	@patch
	factory Map() = JsLinkedHashMap<K, V>.es6;
	}

	@patch
	class String {
	@patch
	factory String.fromCharCodes(Iterable<int> charCodes,
	[int start = 0, int end]) {

	if (charCodes is JSArray) {
	return _stringFromJSArray(charCodes, start, end);
	}
	if (charCodes is NativeUint8List) {
	return _stringFromUint8List(charCodes, start, end);
	}
	return _stringFromIterable(charCodes, start, end);
	}

	@patch
	factory String.fromCharCode(int charCode) {
	return Primitives.stringFromCharCode(charCode);
	}

	@patch
	factory String.fromEnvironment(String name, {String defaultValue}) {
	throw new UnsupportedError(
	'String.fromEnvironment can only be used as a const constructor');
	}

	static String _stringFromJSArray(List list, int start, int endOrNull) {
	int len = list.length;
	int end = RangeError.checkValidRange(start, endOrNull, len);
	if (start > 0 \|\| end < len) {
	list = list.sublist(start, end);
	}
	return Primitives.stringFromCharCodes(list);
	}

	static String _stringFromUint8List(
	NativeUint8List charCodes, int start, int endOrNull) {
	int len = charCodes.length;
	int end = RangeError.checkValidRange(start, endOrNull, len);
	return Primitives.stringFromNativeUint8List(charCodes, start, end);
	}

	static String _stringFromIterable(Iterable<int> charCodes,
	int start, int end) {
	if (start < 0) throw new RangeError.range(start, 0, charCodes.length);
	if (end != null && end < start) {
	throw new RangeError.range(end, start, charCodes.length);
	}
	var it = charCodes.iterator;
	for (int i = 0; i < start; i++) {
	if (!it.moveNext()) {
	throw new RangeError.range(start, 0, i);
	}
	}
	var list = [];
	if (end == null) {
	while (it.moveNext()) list.add(it.current);
	} else {
	for (int i = start; i < end; i++) {
	if (!it.moveNext()) {
	throw new RangeError.range(end, start, i);
	}
	list.add(it.current);
	}
	}
	return Primitives.stringFromCharCodes(list);
	}
	}

	@patch
	class bool {
	@patch
	factory bool.fromEnvironment(String name, {bool defaultValue: false}) {
	throw new UnsupportedError(
	'bool.fromEnvironment can only be used as a const constructor');
	}

	@patch
	int get hashCode => super.hashCode;
	}

	@patch
	class RegExp {
	@NoInline()
	@patch
	factory RegExp(String source,
	{bool multiLine: false,
	bool caseSensitive: true})
	=> new JSSyntaxRegExp(source,
	multiLine: multiLine,
	caseSensitive: caseSensitive);
	}

	// Patch for 'identical' function.
	@NoInline() // No inlining since we recognize the call in optimizer.
	@patch
	bool identical(Object a, Object b) {
	return JS('bool', '(# == null ? # == null : # === #)', a, b, a, b);
	}

	@patch
	class StringBuffer {
	String _contents;

	@patch
	StringBuffer([Object content = ""]) : _contents = '$content';

	@patch
	int get length => _contents.length;

	@patch
	void write(Object obj) {
	_writeString('$obj');
	}

	@patch
	void writeCharCode(int charCode) {
	_writeString(new String.fromCharCode(charCode));
	}

	@patch
	void writeAll(Iterable objects, [String separator = ""]) {
	_contents = _writeAll(_contents, objects, separator);
	}

	@patch
	void writeln([Object obj = ""]) {
	_writeString('$obj\n');
	}

	@patch
	void clear() {
	_contents = "";
	}

	@patch
	String toString() => Primitives.flattenString(_contents);

	void _writeString(str) {
	_contents = Primitives.stringConcatUnchecked(_contents, str);
	}

	static String _writeAll(String string, Iterable objects, String separator) {
	Iterator iterator = objects.iterator;
	if (!iterator.moveNext()) return string;
	if (separator.isEmpty) {
	do {
	string = _writeOne(string, iterator.current);
	} while (iterator.moveNext());
	} else {
	string = _writeOne(string, iterator.current);
	while (iterator.moveNext()) {
	string = _writeOne(string, separator);
	string = _writeOne(string, iterator.current);
	}
	}
	return string;
	}

	static String _writeOne(String string, Object obj) {
	return Primitives.stringConcatUnchecked(string, '$obj');
	}
	}

	@patch
	class NoSuchMethodError {
	@patch
	NoSuchMethodError(Object receiver,
	Symbol memberName,
	List positionalArguments,
	Map<Symbol, dynamic> namedArguments,
	[List existingArgumentNames = null])
	: _receiver = receiver,
	_memberName = memberName,
	_arguments = positionalArguments,
	_namedArguments = namedArguments,
	_existingArgumentNames = existingArgumentNames;

	@patch
	String toString() {
	StringBuffer sb = new StringBuffer('');
	String comma = '';
	if (_arguments != null) {
	for (var argument in _arguments) {
	sb.write(comma);
	sb.write(Error.safeToString(argument));
	comma = ', ';
	}
	}
	if (_namedArguments != null) {
	_namedArguments.forEach((Symbol key, var value) {
	sb.write(comma);
	sb.write(_symbolToString(key));
	sb.write(": ");
	sb.write(Error.safeToString(value));
	comma = ', ';
	});
	}
	String memberName = _symbolToString(_memberName);
	String receiverText = Error.safeToString(_receiver);
	String actualParameters = '$sb';
	if (_existingArgumentNames == null) {
	return "NoSuchMethodError: method not found: '$memberName'\n"
	"Receiver: ${receiverText}\n"
	"Arguments: [$actualParameters]";
	} else {
	String formalParameters = _existingArgumentNames.join(', ');
	return "NoSuchMethodError: incorrect number of arguments passed to "
	"method named '$memberName'\n"
	"Receiver: ${receiverText}\n"
	"Tried calling: $memberName($actualParameters)\n"
	"Found: $memberName($formalParameters)";
	}
	}
	}

	@patch
	class Uri {
	@patch
	static Uri get base {
	String uri = Primitives.currentUri();
	if (uri != null) return Uri.parse(uri);
	throw new UnsupportedError("'Uri.base' is not supported");
	}
	}

	@patch
	class _Uri {
	@patch
	static bool get _isWindows => false;

	// Matches a String that _uriEncodes to itself regardless of the kind of
	// component. This corresponds to [_unreservedTable], i.e. characters that
	// are not encoded by any encoding table.
	static final RegExp _needsNoEncoding = new RegExp(r'^[\-\.0-9A-Z_a-z~]*$');

	/**
	* This is the internal implementation of JavaScript's encodeURI function.
	* It encodes all characters in the string [text] except for those
	* that appear in [canonicalTable], and returns the escaped string.
	*/
	@patch
	static String _uriEncode(List<int> canonicalTable,
	String text,
	Encoding encoding,
	bool spaceToPlus) {
	if (identical(encoding, UTF8) && _needsNoEncoding.hasMatch(text)) {
	return text;
	}

	// Encode the string into bytes then generate an ASCII only string
	// by percent encoding selected bytes.
	StringBuffer result = new StringBuffer('');
	var bytes = encoding.encode(text);
	for (int i = 0; i < bytes.length; i++) {
	int byte = bytes[i];
	if (byte < 128 &&
	((canonicalTable[byte >> 4] & (1 << (byte & 0x0f))) != 0)) {
	result.writeCharCode(byte);
	} else if (spaceToPlus && byte == _SPACE) {
	result.write('+');
	} else {
	const String hexDigits = '0123456789ABCDEF';
	result.write('%');
	result.write(hexDigits[(byte >> 4) & 0x0f]);
	result.write(hexDigits[byte & 0x0f]);
	}
	}
	return result.toString();
	}
	}

	Uri _resolvePackageUri(Uri packageUri) {
	assert(packageUri.scheme == "package");
	if (packageUri.hasAuthority) {
	throw new ArgumentError("Package-URI must not have a host: $packageUri");
	}
	var resolved = Uri.base.resolve("packages/${packageUri.path}");
	return resolved;
	}

	@patch
	class StackTrace {
	@patch
	@NoInline()
	static StackTrace get current {
	if (JS('', 'Error.captureStackTrace') != null) {
	var error = JS('', 'new Error()');
	JS('void', 'Error.captureStackTrace(#)', error);
	return getTraceFromException(error);
	}
	// Fallback if Error.captureStackTrace does not exist.
	try {
	throw '';
	} catch (_, stackTrace) {
	return stackTrace;
	}
	}
	}

	// Called from kernel generated code.
	_malformedTypeError(message) => new RuntimeError(message);

	// Called from kernel generated code.
	_genericNoSuchMethod(receiver, memberName, positionalArguments, namedArguments,
	existingArguments) {
	return new NoSuchMethodError(
	receiver,
	memberName,
	positionalArguments,
	namedArguments);
	}

	// Called from kernel generated code.
	_unresolvedConstructorError(receiver, memberName, positionalArguments,
	namedArguments, existingArguments) {
	// TODO(sra): Generate an error that reads:
	//
	// No constructor '$memberName' declared in class '$receiver'.

	return new NoSuchMethodError(
	receiver,
	memberName,
	positionalArguments,
	namedArguments);
	}

	// Called from kernel generated code.
	_unresolvedStaticGetterError(receiver, memberName, positionalArguments,
	namedArguments, existingArguments) {
	// TODO(sra): Generate customized message.
	return new NoSuchMethodError(
	receiver,
	memberName,
	positionalArguments,
	namedArguments);
	}

	// Called from kernel generated code.
	_unresolvedStaticSetterError(receiver, memberName, positionalArguments,
	namedArguments, existingArguments) {
	// TODO(sra): Generate customized message.
	return new NoSuchMethodError(
	receiver,
	memberName,
	positionalArguments,
	namedArguments);
	}

	// Called from kernel generated code.
	_unresolvedStaticMethodError(receiver, memberName, positionalArguments,
	namedArguments, existingArguments) {
	// TODO(sra): Generate customized message.
	return new NoSuchMethodError(
	receiver,
	memberName,
	positionalArguments,
	namedArguments);
	}

	// Called from kernel generated code.
	_unresolvedTopLevelGetterError(receiver, memberName, positionalArguments,
	namedArguments, existingArguments) {
	// TODO(sra): Generate customized message.
	return new NoSuchMethodError(
	receiver,
	memberName,
	positionalArguments,
	namedArguments);
	}

	// Called from kernel generated code.
	_unresolvedTopLevelSetterError(receiver, memberName, positionalArguments,
	namedArguments, existingArguments) {
	// TODO(sra): Generate customized message.
	return new NoSuchMethodError(
	receiver,
	memberName,
	positionalArguments,
	namedArguments);
	}

	// Called from kernel generated code.
	_unresolvedTopLevelMethodError(receiver, memberName, positionalArguments,
	namedArguments, existingArguments) {
	// TODO(sra): Generate customized message.
	return new NoSuchMethodError(
	receiver,
	memberName,
	positionalArguments,
	namedArguments);
	}