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pkg/dev_compiler/tool/input_sdk/lib/convert/json.dart

Index: pkg/dev_compiler/tool/input_sdk/lib/convert/json.dart
diff --git a/pkg/dev_compiler/tool/input_sdk/lib/convert/json.dart b/pkg/dev_compiler/tool/input_sdk/lib/convert/json.dart
deleted file mode 100644
index 24931df19496e9b18f0a7f6aa101a553b1ddebb0..0000000000000000000000000000000000000000
--- a/pkg/dev_compiler/tool/input_sdk/lib/convert/json.dart
+++ /dev/null
@@ -1,1064 +0,0 @@
-// Copyright (c) 2013, 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.
-
-part of dart.convert;
-
-/**
- * Error thrown by JSON serialization if an object cannot be serialized.
- *
- * The [unsupportedObject] field holds that object that failed to be serialized.
- *
- * If an object isn't directly serializable, the serializer calls the `toJson`
- * method on the object. If that call fails, the error will be stored in the
- * [cause] field. If the call returns an object that isn't directly
- * serializable, the [cause] is null.
- */
-class JsonUnsupportedObjectError extends Error {
-  /** The object that could not be serialized. */
-  final unsupportedObject;
-  /** The exception thrown when trying to convert the object. */
-  final cause;
-
-  JsonUnsupportedObjectError(this.unsupportedObject, { this.cause });
-
-  String toString() {
-    if (cause != null) {
-      return "Converting object to an encodable object failed.";
-    } else {
-      return "Converting object did not return an encodable object.";
-    }
-  }
-}
-
-
-/**
- * Reports that an object could not be stringified due to cyclic references.
- *
- * An object that references itself cannot be serialized by [stringify].
- * When the cycle is detected, a [JsonCyclicError] is thrown.
- */
-class JsonCyclicError extends JsonUnsupportedObjectError {
-  /** The first object that was detected as part of a cycle. */
-  JsonCyclicError(Object object): super(object);
-  String toString() => "Cyclic error in JSON stringify";
-}
-
-
-/**
- * An instance of the default implementation of the [JsonCodec].
- *
- * This instance provides a convenient access to the most common JSON
- * use cases.
- *
- * Examples:
- *
- *     var encoded = JSON.encode([1, 2, { "a": null }]);
- *     var decoded = JSON.decode('["foo", { "bar": 499 }]');
- */
-const JsonCodec JSON = const JsonCodec();
-
-typedef _Reviver(var key, var value);
-typedef _ToEncodable(var o);
-
-
-/**
- * A [JsonCodec] encodes JSON objects to strings and decodes strings to
- * JSON objects.
- *
- * Examples:
- *
- *     var encoded = JSON.encode([1, 2, { "a": null }]);
- *     var decoded = JSON.decode('["foo", { "bar": 499 }]');
- */
-class JsonCodec extends Codec<Object, String> {
-  final _Reviver _reviver;
-  final _ToEncodable _toEncodable;
-
-  /**
-   * Creates a `JsonCodec` with the given reviver and encoding function.
-   *
-   * The [reviver] function is called during decoding. It is invoked once for
-   * each object or list property that has been parsed.
-   * The `key` argument is either the integer list index for a list property,
-   * the string map key for object properties, or `null` for the final result.
-   *
-   * If [reviver] is omitted, it defaults to returning the value argument.
-   *
-   * The [toEncodable] function is used during encoding. It is invoked for
-   * values that are not directly encodable to a string (a value that is not a
-   * number, boolean, string, null, list or a map with string keys). The
-   * function must return an object that is directly encodable. The elements of
-   * a returned list and values of a returned map do not need to be directly
-   * encodable, and if they aren't, `toEncodable` will be used on them as well.
-   * Please notice that it is possible to cause an infinite recursive regress
-   * in this way, by effectively creating an infinite data structure through
-   * repeated call to `toEncodable`.
-   *
-   * If [toEncodable] is omitted, it defaults to a function that returns the
-   * result of calling `.toJson()` on the unencodable object.
-   */
-  const JsonCodec({reviver(var key, var value), toEncodable(var object)})
-      : _reviver = reviver,
-        _toEncodable = toEncodable;
-
-  /**
-   * Creates a `JsonCodec` with the given reviver.
-   *
-   * The [reviver] function is called once for each object or list property
-   * that has been parsed during decoding. The `key` argument is either the
-   * integer list index for a list property, the string map key for object
-   * properties, or `null` for the final result.
-   */
-  JsonCodec.withReviver(reviver(var key, var value)) : this(reviver: reviver);
-
-  /**
-   * Parses the string and returns the resulting Json object.
-   *
-   * The optional [reviver] function is called once for each object or list
-   * property that has been parsed during decoding. The `key` argument is either
-   * the integer list index for a list property, the string map key for object
-   * properties, or `null` for the final result.
-   *
-   * The default [reviver] (when not provided) is the identity function.
-   */
-  dynamic decode(String source, {reviver(var key, var value)}) {
-    if (reviver == null) reviver = _reviver;
-    if (reviver == null) return decoder.convert(source);
-    return new JsonDecoder(reviver).convert(source);
-  }
-
-  /**
-   * Converts [value] to a JSON string.
-   *
-   * If value contains objects that are not directly encodable to a JSON
-   * string (a value that is not a number, boolean, string, null, list or a map
-   * with string keys), the [toEncodable] function is used to convert it to an
-   * object that must be directly encodable.
-   *
-   * If [toEncodable] is omitted, it defaults to a function that returns the
-   * result of calling `.toJson()` on the unencodable object.
-   */
-  String encode(Object value, {toEncodable(object)}) {
-    if (toEncodable == null) toEncodable = _toEncodable;
-    if (toEncodable == null) return encoder.convert(value);
-    return new JsonEncoder(toEncodable).convert(value);
-  }
-
-  JsonEncoder get encoder {
-    if (_toEncodable == null) return const JsonEncoder();
-    return new JsonEncoder(_toEncodable);
-  }
-
-  JsonDecoder get decoder {
-    if (_reviver == null) return const JsonDecoder();
-    return new JsonDecoder(_reviver);
-  }
-}
-
-/**
- * This class converts JSON objects to strings.
- */
-class JsonEncoder extends Converter<Object, String> {
-  /**
-   * The string used for indention.
-   *
-   * When generating multi-line output, this string is inserted once at the
-   * beginning of each indented line for each level of indentation.
-   *
-   * If `null`, the output is encoded as a single line.
-   */
-  final String indent;
-
-  /**
-   * Function called on non-encodable objects to return a replacement
-   * encodable object that will be encoded in the orignal's place.
-   */
-  final _ToEncodable _toEncodable;
-
-  /**
-   * Creates a JSON encoder.
-   *
-   * The JSON encoder handles numbers, strings, booleans, null, lists and
-   * maps directly.
-   *
-   * Any other object is attempted converted by [toEncodable] to an
-   * object that is of one of the convertible types.
-   *
-   * If [toEncodable] is omitted, it defaults to calling `.toJson()` on
-   * the object.
-   */
-  const JsonEncoder([toEncodable(nonSerializable)])
-      : this.indent = null,
-        this._toEncodable = toEncodable;
-
-  /**
-   * Creates a JSON encoder that creates multi-line JSON.
-   *
-   * The encoding of elements of lists and maps are indented and put on separate
-   * lines. The [indent] string is prepended to these elements, once for each
-   * level of indentation.
-   *
-   * If [indent] is `null`, the output is encoded as a single line.
-   *
-   * The JSON encoder handles numbers, strings, booleans, null, lists and
-   * maps directly.
-   *
-   * Any other object is attempted converted by [toEncodable] to an
-   * object that is of one of the convertible types.
-   *
-   * If [toEncodable] is omitted, it defaults to calling `.toJson()` on
-   * the object.
-   */
-  const JsonEncoder.withIndent(this.indent, [toEncodable(nonSerializable)])
-      : this._toEncodable = toEncodable;
-
-  /**
-   * Converts [object] to a JSON [String].
-   *
-   * Directly serializable values are [num], [String], [bool], and [Null], as
-   * well as some [List] and [Map] values. For [List], the elements must all be
-   * serializable. For [Map], the keys must be [String] and the values must be
-   * serializable.
-   *
-   * If a value of any other type is attempted to be serialized, the
-   * `toEncodable` function provided in the constructor is called with the value
-   * as argument. The result, which must be a directly serializable value, is
-   * serialized instead of the original value.
-   *
-   * If the conversion throws, or returns a value that is not directly
-   * serializable, a [JsonUnsupportedObjectError] exception is thrown.
-   * If the call throws, the error is caught and stored in the
-   * [JsonUnsupportedObjectError]'s [:cause:] field.
-   *
-   * If a [List] or [Map] contains a reference to itself, directly or through
-   * other lists or maps, it cannot be serialized and a [JsonCyclicError] is
-   * thrown.
-   *
-   * [object] should not change during serialization.
-   *
-   * If an object is serialized more than once, [convert] may cache the text
-   * for it. In other words, if the content of an object changes after it is
-   * first serialized, the new values may not be reflected in the result.
-   */
-  String convert(Object object) =>
-      _JsonStringStringifier.stringify(object, _toEncodable, indent);
-
-  /**
-   * Starts a chunked conversion.
-   *
-   * The converter works more efficiently if the given [sink] is a
-   * [StringConversionSink].
-   *
-   * Returns a chunked-conversion sink that accepts at most one object. It is
-   * an error to invoke `add` more than once on the returned sink.
-   */
-  ChunkedConversionSink<Object> startChunkedConversion(Sink<String> sink) {
-    if (sink is! StringConversionSink) {
-      sink = new StringConversionSink.from(sink);
-    } else if (sink is _Utf8EncoderSink) {
-      return new _JsonUtf8EncoderSink(sink._sink, _toEncodable,
-                                      JsonUtf8Encoder._utf8Encode(indent),
-                                      JsonUtf8Encoder.DEFAULT_BUFFER_SIZE);
-    }
-    return new _JsonEncoderSink(sink, _toEncodable, indent);
-  }
-
-  // Override the base class's bind, to provide a better type.
-  Stream<String> bind(Stream<Object> stream) => super.bind(stream);
-
-  Converter<Object, dynamic/*=T*/> fuse/*<T>*/(
-      Converter<String, dynamic/*=T*/> other) {
-    if (other is Utf8Encoder) {
-      return new JsonUtf8Encoder(indent, _toEncodable)
-          as dynamic/*=Converter<Object, T>*/;
-    }
-    return super.fuse/*<T>*/(other);
-  }
-}
-
-/**
- * Encoder that encodes a single object as a UTF-8 encoded JSON string.
- *
- * This encoder works equivalently to first converting the object to
- * a JSON string, and then UTF-8 encoding the string, but without
- * creating an intermediate string.
- */
-class JsonUtf8Encoder extends Converter<Object, List<int>> {
-  /** Default buffer size used by the JSON-to-UTF-8 encoder. */
-  static const int DEFAULT_BUFFER_SIZE = 256;
-  /** Indentation used in pretty-print mode, `null` if not pretty. */
-  final List<int> _indent;
-  /** Function called with each un-encodable object encountered. */
-  final _ToEncodable _toEncodable;
-  /** UTF-8 buffer size. */
-  final int _bufferSize;
-
-  /**
-   * Create converter.
-   *
-   * If [indent] is non-`null`, the converter attempts to "pretty-print" the
-   * JSON, and uses `indent` as the indentation. Otherwise the result has no
-   * whitespace outside of string literals.
-   * If `indent` contains characters that are not valid JSON whitespace
-   * characters, the result will not be valid JSON. JSON whitespace characters
-   * are space (U+0020), tab (U+0009), line feed (U+000a) and carriage return
-   * (U+000d) ([ECMA
-   * 404](http://www.ecma-international.org/publications/standards/Ecma-404.htm)).
-   *
-   * The [bufferSize] is the size of the internal buffers used to collect
-   * UTF-8 code units.
-   * If using [startChunkedConversion], it will be the size of the chunks.
-   *
-   * The JSON encoder handles numbers, strings, booleans, null, lists and maps
-   * directly.
-   *
-   * Any other object is attempted converted by [toEncodable] to an object that
-   * is of one of the convertible types.
-   *
-   * If [toEncodable] is omitted, it defaults to calling `.toJson()` on the
-   * object.
-   */
-  JsonUtf8Encoder([String indent,
-                   toEncodable(object),
-                   int bufferSize = DEFAULT_BUFFER_SIZE])
-      : _indent = _utf8Encode(indent),
-        _toEncodable = toEncodable,
-        _bufferSize = bufferSize;
-
-  static List<int> _utf8Encode(String string) {
-    if (string == null) return null;
-    if (string.isEmpty) return new Uint8List(0);
-    checkAscii: {
-      for (int i = 0; i < string.length; i++) {
-        if (string.codeUnitAt(i) >= 0x80) break checkAscii;
-      }
-      return string.codeUnits;
-    }
-    return UTF8.encode(string);
-  }
-
-  /** Convert [object] into UTF-8 encoded JSON. */
-  List<int> convert(Object object) {
-    List<List<int>> bytes = [];
-    // The `stringify` function always converts into chunks.
-    // Collect the chunks into the `bytes` list, then combine them afterwards.
-    void addChunk(Uint8List chunk, int start, int end) {
-      if (start > 0 || end < chunk.length) {
-        int length = end - start;
-        chunk = new Uint8List.view(chunk.buffer,
-                                   chunk.offsetInBytes + start,
-                                   length);
-      }
-      bytes.add(chunk);
-    }
-    _JsonUtf8Stringifier.stringify(object,
-                                   _indent,
-                                   _toEncodable,
-                                   _bufferSize,
-                                   addChunk);
-    if (bytes.length == 1) return bytes[0];
-    int length = 0;
-    for (int i = 0; i < bytes.length; i++) {
-      length += bytes[i].length;
-    }
-    Uint8List result = new Uint8List(length);
-    for (int i = 0, offset = 0; i < bytes.length; i++) {
-      var byteList = bytes[i];
-      int end = offset + byteList.length;
-      result.setRange(offset, end, byteList);
-      offset = end;
-    }
-    return result;
-  }
-
-  /**
-   * Start a chunked conversion.
-   *
-   * Only one object can be passed into the returned sink.
-   *
-   * The argument [sink] will receive byte lists in sizes depending on the
-   * `bufferSize` passed to the constructor when creating this encoder.
-   */
-  ChunkedConversionSink<Object> startChunkedConversion(Sink<List<int>> sink) {
-    ByteConversionSink byteSink;
-    if (sink is ByteConversionSink) {
-      byteSink = sink;
-    } else {
-      byteSink = new ByteConversionSink.from(sink);
-    }
-    return new _JsonUtf8EncoderSink(byteSink, _toEncodable,
-                                    _indent, _bufferSize);
-  }
-
-  // Override the base class's bind, to provide a better type.
-  Stream<List<int>> bind(Stream<Object> stream) {
-    return super.bind(stream);
-  }
-}
-
-/**
- * Implements the chunked conversion from object to its JSON representation.
- *
- * The sink only accepts one value, but will produce output in a chunked way.
- */
-class _JsonEncoderSink extends ChunkedConversionSink<Object> {
-  final String _indent;
-  final _ToEncodable _toEncodable;
-  final StringConversionSink _sink;
-  bool _isDone = false;
-
-  _JsonEncoderSink(this._sink, this._toEncodable, this._indent);
-
-  /**
-   * Encodes the given object [o].
-   *
-   * It is an error to invoke this method more than once on any instance. While
-   * this makes the input effectly non-chunked the output will be generated in
-   * a chunked way.
-   */
-  void add(Object o) {
-    if (_isDone) {
-      throw new StateError("Only one call to add allowed");
-    }
-    _isDone = true;
-    ClosableStringSink stringSink = _sink.asStringSink();
-    _JsonStringStringifier.printOn(o, stringSink, _toEncodable, _indent);
-    stringSink.close();
-  }
-
-  void close() { /* do nothing */ }
-}
-
-/**
- * Sink returned when starting a chunked conversion from object to bytes.
- */
-class _JsonUtf8EncoderSink extends ChunkedConversionSink<Object> {
-  /** The byte sink receiveing the encoded chunks. */
-  final ByteConversionSink _sink;
-  final List<int> _indent;
-  final _ToEncodable _toEncodable;
-  final int _bufferSize;
-  bool _isDone = false;
-  _JsonUtf8EncoderSink(this._sink, this._toEncodable, this._indent,
-                       this._bufferSize);
-
-  /** Callback called for each slice of result bytes. */
-  void _addChunk(Uint8List chunk, int start, int end) {
-    _sink.addSlice(chunk, start, end, false);
-  }
-
-  void add(Object object) {
-    if (_isDone) {
-      throw new StateError("Only one call to add allowed");
-    }
-    _isDone = true;
-    _JsonUtf8Stringifier.stringify(object, _indent, _toEncodable,
-                                   _bufferSize,
-                                   _addChunk);
-    _sink.close();
-  }
-
-  void close() {
-    if (!_isDone) {
-      _isDone = true;
-      _sink.close();
-    }
-  }
-}
-
-/**
- * This class parses JSON strings and builds the corresponding objects.
- */
-class JsonDecoder extends Converter<String, Object> {
-  final _Reviver _reviver;
-  /**
-   * Constructs a new JsonDecoder.
-   *
-   * The [reviver] may be `null`.
-   */
-  const JsonDecoder([reviver(var key, var value)]) : this._reviver = reviver;
-
-  /**
-   * Converts the given JSON-string [input] to its corresponding object.
-   *
-   * Parsed JSON values are of the types [num], [String], [bool], [Null],
-   * [List]s of parsed JSON values or [Map]s from [String] to parsed JSON
-   * values.
-   *
-   * If `this` was initialized with a reviver, then the parsing operation
-   * invokes the reviver on every object or list property that has been parsed.
-   * The arguments are the property name ([String]) or list index ([int]), and
-   * the value is the parsed value. The return value of the reviver is used as
-   * the value of that property instead the parsed value.
-   *
-   * Throws [FormatException] if the input is not valid JSON text.
-   */
-  dynamic convert(String input) => _parseJson(input, _reviver);
-
-  /**
-   * Starts a conversion from a chunked JSON string to its corresponding object.
-   *
-   * The output [sink] receives exactly one decoded element through `add`.
-   */
-  external StringConversionSink startChunkedConversion(Sink<Object> sink);
-
-  // Override the base class's bind, to provide a better type.
-  Stream<Object> bind(Stream<String> stream) => super.bind(stream);
-}
-
-// Internal optimized JSON parsing implementation.
-external _parseJson(String source, reviver(key, value));
-
-
-// Implementation of encoder/stringifier.
-
-dynamic _defaultToEncodable(dynamic object) => object.toJson();
-
-/**
- * JSON encoder that traverses an object structure and writes JSON source.
- *
- * This is an abstract implementation that doesn't decide on the output
- * format, but writes the JSON through abstract methods like [writeString].
- */
-abstract class _JsonStringifier {
-  // Character code constants.
-  static const int BACKSPACE       = 0x08;
-  static const int TAB             = 0x09;
-  static const int NEWLINE         = 0x0a;
-  static const int CARRIAGE_RETURN = 0x0d;
-  static const int FORM_FEED       = 0x0c;
-  static const int QUOTE           = 0x22;
-  static const int CHAR_0          = 0x30;
-  static const int BACKSLASH       = 0x5c;
-  static const int CHAR_b          = 0x62;
-  static const int CHAR_f          = 0x66;
-  static const int CHAR_n          = 0x6e;
-  static const int CHAR_r          = 0x72;
-  static const int CHAR_t          = 0x74;
-  static const int CHAR_u          = 0x75;
-
-  /** List of objects currently being traversed. Used to detect cycles. */
-  final List _seen = new List();
-  /** Function called for each un-encodable object encountered. */
-  final _ToEncodable _toEncodable;
-
-  _JsonStringifier(toEncodable(o))
-      : _toEncodable = toEncodable ?? _defaultToEncodable;
-
-  /** Append a string to the JSON output. */
-  void writeString(String characters);
-  /** Append part of a string to the JSON output. */
-  void writeStringSlice(String characters, int start, int end);
-  /** Append a single character, given by its code point, to the JSON output. */
-  void writeCharCode(int charCode);
-  /** Write a number to the JSON output. */
-  void writeNumber(num number);
-
-  // ('0' + x) or ('a' + x - 10)
-  static int hexDigit(int x) => x < 10 ? 48 + x : 87 + x;
-
-  /**
-   * Write, and suitably escape, a string's content as a JSON string literal.
-   */
-  void writeStringContent(String s) {
-    int offset = 0;
-    final int length = s.length;
-    for (int i = 0; i < length; i++) {
-      int charCode = s.codeUnitAt(i);
-      if (charCode > BACKSLASH) continue;
-      if (charCode < 32) {
-        if (i > offset) writeStringSlice(s, offset, i);
-        offset = i + 1;
-        writeCharCode(BACKSLASH);
-        switch (charCode) {
-        case BACKSPACE:
-          writeCharCode(CHAR_b);
-          break;
-        case TAB:
-          writeCharCode(CHAR_t);
-          break;
-        case NEWLINE:
-          writeCharCode(CHAR_n);
-          break;
-        case FORM_FEED:
-          writeCharCode(CHAR_f);
-          break;
-        case CARRIAGE_RETURN:
-          writeCharCode(CHAR_r);
-          break;
-        default:
-          writeCharCode(CHAR_u);
-          writeCharCode(CHAR_0);
-          writeCharCode(CHAR_0);
-          writeCharCode(hexDigit((charCode >> 4) & 0xf));
-          writeCharCode(hexDigit(charCode & 0xf));
-          break;
-        }
-      } else if (charCode == QUOTE || charCode == BACKSLASH) {
-        if (i > offset) writeStringSlice(s, offset, i);
-        offset = i + 1;
-        writeCharCode(BACKSLASH);
-        writeCharCode(charCode);
-      }
-    }
-    if (offset == 0) {
-      writeString(s);
-    } else if (offset < length) {
-      writeStringSlice(s, offset, length);
-    }
-  }
-
-  /**
-   * Check if an encountered object is already being traversed.
-   *
-   * Records the object if it isn't already seen. Should have a matching call to
-   * [_removeSeen] when the object is no longer being traversed.
-   */
-  void _checkCycle(object) {
-    for (int i = 0; i < _seen.length; i++) {
-      if (identical(object, _seen[i])) {
-        throw new JsonCyclicError(object);
-      }
-    }
-    _seen.add(object);
-  }
-
-  /**
-   * Remove [object] from the list of currently traversed objects.
-   *
-   * Should be called in the opposite order of the matching [_checkCycle]
-   * calls.
-   */
-  void _removeSeen(object) {
-    assert(!_seen.isEmpty);
-    assert(identical(_seen.last, object));
-    _seen.removeLast();
-  }
-
-  /**
-   * Write an object.
-   *
-   * If [object] isn't directly encodable, the [_toEncodable] function gets one
-   * chance to return a replacement which is encodable.
-   */
-  void writeObject(object) {
-    // Tries stringifying object directly. If it's not a simple value, List or
-    // Map, call toJson() to get a custom representation and try serializing
-    // that.
-    if (writeJsonValue(object)) return;
-    _checkCycle(object);
-    try {
-      var customJson = _toEncodable(object);
-      if (!writeJsonValue(customJson)) {
-        throw new JsonUnsupportedObjectError(object);
-      }
-      _removeSeen(object);
-    } catch (e) {
-      throw new JsonUnsupportedObjectError(object, cause: e);
-    }
-  }
-
-  /**
-   * Serialize a [num], [String], [bool], [Null], [List] or [Map] value.
-   *
-   * Returns true if the value is one of these types, and false if not.
-   * If a value is both a [List] and a [Map], it's serialized as a [List].
-   */
-  bool writeJsonValue(object) {
-    if (object is num) {
-      if (!object.isFinite) return false;
-      writeNumber(object);
-      return true;
-    } else if (identical(object, true)) {
-      writeString('true');
-      return true;
-    } else if (identical(object, false)) {
-      writeString('false');
-       return true;
-    } else if (object == null) {
-      writeString('null');
-      return true;
-    } else if (object is String) {
-      writeString('"');
-      writeStringContent(object);
-      writeString('"');
-      return true;
-    } else if (object is List) {
-      _checkCycle(object);
-      writeList(object);
-      _removeSeen(object);
-      return true;
-    } else if (object is Map) {
-      _checkCycle(object);
-      // writeMap can fail if keys are not all strings.
-      var success = writeMap(object);
-      _removeSeen(object);
-      return success;
-    } else {
-      return false;
-    }
-  }
-
-  /** Serialize a [List]. */
-  void writeList(List list) {
-    writeString('[');
-    if (list.length > 0) {
-      writeObject(list[0]);
-      for (int i = 1; i < list.length; i++) {
-        writeString(',');
-        writeObject(list[i]);
-      }
-    }
-    writeString(']');
-  }
-
-  /** Serialize a [Map]. */
-  bool writeMap(Map map) {
-    if (map.isEmpty) {
-      writeString("{}");
-      return true;
-    }
-    List keyValueList = new List(map.length * 2);
-    int i = 0;
-    bool allStringKeys = true;
-    map.forEach((key, value) {
-      if (key is! String) {
-        allStringKeys = false;
-      }
-      keyValueList[i++] = key;
-      keyValueList[i++] = value;
-    });
-    if (!allStringKeys) return false;
-    writeString('{');
-    String separator = '"';
-    for (int i = 0; i < keyValueList.length; i += 2) {
-      writeString(separator);
-      separator = ',"';
-      writeStringContent(keyValueList[i]);
-      writeString('":');
-      writeObject(keyValueList[i + 1]);
-    }
-    writeString('}');
-    return true;
-  }
-}
-
-/**
- * A modification of [_JsonStringifier] which indents the contents of [List] and
- * [Map] objects using the specified indent value.
- *
- * Subclasses should implement [writeIndentation].
- */
-abstract class _JsonPrettyPrintMixin implements _JsonStringifier {
-  int _indentLevel = 0;
-
-  /**
-   * Add [indentLevel] indentations to the JSON output.
-   */
-  void writeIndentation(int indentLevel);
-
-  void writeList(List list) {
-    if (list.isEmpty) {
-      writeString('[]');
-    } else {
-      writeString('[\n');
-      _indentLevel++;
-      writeIndentation(_indentLevel);
-      writeObject(list[0]);
-      for (int i = 1; i < list.length; i++) {
-        writeString(',\n');
-        writeIndentation(_indentLevel);
-        writeObject(list[i]);
-      }
-      writeString('\n');
-      _indentLevel--;
-      writeIndentation(_indentLevel);
-      writeString(']');
-    }
-  }
-
-  bool writeMap(Map map) {
-    if (map.isEmpty) {
-      writeString("{}");
-      return true;
-    }
-    List keyValueList = new List(map.length * 2);
-    int i = 0;
-    bool allStringKeys = true;
-    map.forEach((key, value) {
-      if (key is! String) {
-        allStringKeys = false;
-      }
-      keyValueList[i++] = key;
-      keyValueList[i++] = value;
-    });
-    if (!allStringKeys) return false;
-    writeString('{\n');
-    _indentLevel++;
-    String separator = "";
-    for (int i = 0; i < keyValueList.length; i += 2) {
-      writeString(separator);
-      separator = ",\n";
-      writeIndentation(_indentLevel);
-      writeString('"');
-      writeStringContent(keyValueList[i]);
-      writeString('": ');
-      writeObject(keyValueList[i + 1]);
-    }
-    writeString('\n');
-    _indentLevel--;
-    writeIndentation(_indentLevel);
-    writeString('}');
-    return true;
-  }
-}
-
-/**
- * A specialziation of [_JsonStringifier] that writes its JSON to a string.
- */
-class _JsonStringStringifier extends _JsonStringifier {
-  final StringSink _sink;
-
-  _JsonStringStringifier(this._sink, _toEncodable) : super(_toEncodable);
-
-  /**
-   * Convert object to a string.
-   *
-   * The [toEncodable] function is used to convert non-encodable objects
-   * to encodable ones.
-   *
-   * If [indent] is not `null`, the resulting JSON will be "pretty-printed"
-   * with newlines and indentation. The `indent` string is added as indentation
-   * for each indentation level. It should only contain valid JSON whitespace
-   * characters (space, tab, carriage return or line feed).
-   */
-  static String stringify(object, toEncodable(o), String indent) {
-    StringBuffer output = new StringBuffer();
-    printOn(object, output, toEncodable, indent);
-    return output.toString();
-  }
-
-  /**
-   * Convert object to a string, and write the result to the [output] sink.
-   *
-   * The result is written piecemally to the sink.
-   */
-  static void printOn(
-      object, StringSink output, toEncodable(o), String indent) {
-    var stringifier;
-    if (indent == null) {
-      stringifier = new _JsonStringStringifier(output, toEncodable);
-    } else {
-      stringifier =
-          new _JsonStringStringifierPretty(output, toEncodable, indent);
-    }
-    stringifier.writeObject(object);
-  }
-
-  void writeNumber(num number) {
-    _sink.write(number.toString());
-  }
-  void writeString(String string) {
-    _sink.write(string);
-  }
-  void writeStringSlice(String string, int start, int end) {
-    _sink.write(string.substring(start, end));
-  }
-  void writeCharCode(int charCode) {
-    _sink.writeCharCode(charCode);
-  }
-}
-
-class _JsonStringStringifierPretty extends _JsonStringStringifier
-                                   with _JsonPrettyPrintMixin {
-  final String _indent;
-
-  _JsonStringStringifierPretty(StringSink sink, toEncodable(o), this._indent)
-      : super(sink, toEncodable);
-
-  void writeIndentation(int count) {
-    for (int i = 0; i < count; i++) writeString(_indent);
-  }
-}
-
-typedef void _AddChunk(Uint8List list, int start, int end);
-
-/**
- * Specialization of [_JsonStringifier] that writes the JSON as UTF-8.
- *
- * The JSON text is UTF-8 encoded and written to [Uint8List] buffers.
- * The buffers are then passed back to a user provided callback method.
- */
-class _JsonUtf8Stringifier extends _JsonStringifier {
-  final int bufferSize;
-  final _AddChunk addChunk;
-  Uint8List buffer;
-  int index = 0;
-
-  _JsonUtf8Stringifier(toEncodable(o), int bufferSize, this.addChunk)
-      : this.bufferSize = bufferSize,
-        buffer = new Uint8List(bufferSize),
-        super(toEncodable);
-
-  /**
-   * Convert [object] to UTF-8 encoded JSON.
-   *
-   * Calls [addChunk] with slices of UTF-8 code units.
-   * These will typically have size [bufferSize], but may be shorter.
-   * The buffers are not reused, so the [addChunk] call may keep and reuse the
-   * chunks.
-   *
-   * If [indent] is non-`null`, the result will be "pretty-printed" with extra
-   * newlines and indentation, using [indent] as the indentation.
-   */
-  static void stringify(Object object,
-                        List<int> indent,
-                        toEncodable(o),
-                        int bufferSize,
-                        void addChunk(Uint8List chunk, int start, int end)) {
-    _JsonUtf8Stringifier stringifier;
-    if (indent != null) {
-      stringifier = new _JsonUtf8StringifierPretty(toEncodable, indent,
-                                                   bufferSize, addChunk);
-    } else {
-      stringifier = new _JsonUtf8Stringifier(toEncodable, bufferSize, addChunk);
-    }
-    stringifier.writeObject(object);
-    stringifier.flush();
-  }
-
-  /**
-   * Must be called at the end to push the last chunk to the [addChunk]
-   * callback.
-   */
-  void flush() {
-    if (index > 0) {
-      addChunk(buffer, 0, index);
-    }
-    buffer = null;
-    index = 0;
-  }
-
-  void writeNumber(num number) {
-    writeAsciiString(number.toString());
-  }
-
-  /** Write a string that is known to not have non-ASCII characters. */
-  void writeAsciiString(String string) {
-    // TODO(lrn): Optimize by copying directly into buffer instead of going
-    // through writeCharCode;
-    for (int i = 0; i < string.length; i++) {
-      int char = string.codeUnitAt(i);
-      assert(char <= 0x7f);
-      writeByte(char);
-    }
-  }
-
-  void writeString(String string) {
-    writeStringSlice(string, 0, string.length);
-  }
-
-  void writeStringSlice(String string, int start, int end) {
-    // TODO(lrn): Optimize by copying directly into buffer instead of going
-    // through writeCharCode/writeByte. Assumption is the most characters
-    // in starings are plain ASCII.
-    for (int i = start; i < end; i++) {
-      int char = string.codeUnitAt(i);
-      if (char <= 0x7f) {
-        writeByte(char);
-      } else {
-        if ((char & 0xFC00) == 0xD800 && i + 1 < end) {
-          // Lead surrogate.
-          int nextChar = string.codeUnitAt(i + 1);
-          if ((nextChar & 0xFC00) == 0xDC00) {
-            // Tail surrogate.
-            char = 0x10000 + ((char & 0x3ff) << 10) + (nextChar & 0x3ff);
-            writeFourByteCharCode(char);
-            i++;
-            continue;
-          }
-        }
-        writeMultiByteCharCode(char);
-      }
-    }
-  }
-
-  void writeCharCode(int charCode) {
-    if (charCode <= 0x7f) {
-      writeByte(charCode);
-      return;
-    }
-    writeMultiByteCharCode(charCode);
-  }
-
-  void writeMultiByteCharCode(int charCode) {
-    if (charCode <= 0x7ff) {
-      writeByte(0xC0 | (charCode >> 6));
-      writeByte(0x80 | (charCode & 0x3f));
-      return;
-    }
-    if (charCode <= 0xffff) {
-      writeByte(0xE0 | (charCode >> 12));
-      writeByte(0x80 | ((charCode >> 6) & 0x3f));
-      writeByte(0x80 | (charCode & 0x3f));
-      return;
-    }
-    writeFourByteCharCode(charCode);
-  }
-
-  void writeFourByteCharCode(int charCode) {
-    assert(charCode <= 0x10ffff);
-    writeByte(0xF0 | (charCode >> 18));
-    writeByte(0x80 | ((charCode >> 12) & 0x3f));
-    writeByte(0x80 | ((charCode >> 6) & 0x3f));
-    writeByte(0x80 | (charCode & 0x3f));
-  }
-
-  void writeByte(int byte) {
-    assert(byte <= 0xff);
-    if (index == buffer.length) {
-      addChunk(buffer, 0, index);
-      buffer = new Uint8List(bufferSize);
-      index = 0;
-    }
-    buffer[index++] = byte;
-  }
-}
-
-/**
- * Pretty-printing version of [_JsonUtf8Stringifier].
- */
-class _JsonUtf8StringifierPretty extends _JsonUtf8Stringifier
-                                 with _JsonPrettyPrintMixin {
-  final List<int> indent;
-  _JsonUtf8StringifierPretty(
-      toEncodable(o), this.indent,
-      bufferSize, void addChunk(Uint8List buffer, int start, int end))
-      : super(toEncodable, bufferSize, addChunk);
-
-  void writeIndentation(int count) {
-    List<int> indent = this.indent;
-    int indentLength = indent.length;
-    if (indentLength == 1) {
-      int char = indent[0];
-      while (count > 0) {
-        writeByte(char);
-        count -= 1;
-      }
-      return;
-    }
-    while (count > 0) {
-      count--;
-      int end = index + indentLength;
-      if (end <= buffer.length) {
-        buffer.setRange(index, end, indent);
-        index = end;
-      } else {
-        for (int i = 0; i < indentLength; i++) {
-          writeByte(indent[i]);
-        }
-      }
-    }
-  }
-}