Add writeString method to OutputStream

runtime/bin/file_impl.dart

 // 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.
 
 class _FileInputStream extends _BaseDataInputStream implements InputStream {
   _FileInputStream(String name) {
     _file = new File(name);
     _data = [];
     _position = 0;
     _file.onError = (String s) {
@@ skipping 73 matching lines @@
     _closed = true;
   }
 
   File _file;
   List<int> _data;
   int _position;
   bool _closed = false;
 }
 
 
-class _FileOutputStream implements OutputStream {
+class _FileOutputStream extends _BaseOutputStream implements OutputStream {
   _FileOutputStream(String name, FileMode mode) {
     _pendingOperations = new List<List<int>>();
     var f = new File(name);
     f.open(mode, (openedFile) {
       _file = openedFile;
       _setupFileHandlers();
       _processPendingOperations();
     });
     f.onError = (e) {
       if (_onError != null) _onError();
@@ skipping 437 matching lines @@
     var length = opened.lengthSync();
     var result = new ByteArray(length);
     var read = opened.readListSync(result, 0, length);
     if (read != length) {
       throw new FileIOException("Failed reading file as bytes: $_name");
     }
     opened.closeSync();
     return result;
   }
 
-  _StringDecoder _getDecoder(encoding) {
-    if (encoding == "UTF-8") {
-      return new _UTF8Decoder();
-    } else if (encoding == "ISO-8859-1") {
-      return new _Latin1Decoder();
-    } else if (encoding == "ASCII") {
-      return new _AsciiDecoder();
-    }
-    throw new FileIOException("Unsupported encoding $_encoding");
-  }
-
-  void readAsText(String encoding, void callback(String text)) {
+  void readAsText(Encoding encoding, void callback(String text)) {
     _asyncUsed = true;
-    var decoder = _getDecoder(encoding);
+    var decoder = _StringDecoders.decoder(encoding);
     readAsBytes((bytes) {
       try {
         decoder.write(bytes);
       } catch (var e) {
         if (_onError != null) {
           _onError(e.toString());
           return;
         }
       }
       callback(decoder.decoded);
     });
   }
 
-  String readAsTextSync([String encoding = 'UTF-8']) {
+  String readAsTextSync([Encoding encoding = Encoding.UTF_8]) {
     if (_asyncUsed) {
       throw new FileIOException(
           "Mixed use of synchronous and asynchronous API");
     }
-    var decoder = _getDecoder(encoding);
+    var decoder = _StringDecoders.decoder(encoding);
     List<int> bytes = readAsBytesSync();
     decoder.write(bytes);
     return decoder.decoded;
   }
 
   List<String> _getDecodedLines(_StringDecoder decoder) {
     List<String> result = [];
     var line = decoder.decodedLine;
     while (line != null) {
       result.add(line);
       line = decoder.decodedLine;
     }
     // If there is more data with no terminating line break we treat
     // it as the last line.
     var data = decoder.decoded;
     if (data != null) {
       result.add(data);
     }
     return result;
   }
 
-  void readAsLines(String encoding, void callback(List<String> lines)) {
+  void readAsLines(Encoding encoding, void callback(List<String> lines)) {
     _asyncUsed = true;
-    var decoder = _getDecoder(encoding);
+    var decoder = _StringDecoders.decoder(encoding);
     readAsBytes((bytes) {
       try {
         decoder.write(bytes);
       } catch (var e) {
         if (_onError != null) {
           _onError(e.toString());
           return;
         }
       }
       callback(_getDecodedLines(decoder));
     });
   }
 
-  List<String> readAsLinesSync([String encoding = "UTF-8"]) {
+  List<String> readAsLinesSync([Encoding encoding = Encoding.UTF_8]) {
     if (_asyncUsed) {
       throw new FileIOException(
           "Mixed use of synchronous and asynchronous API");
     }
-    var decoder = _getDecoder(encoding);
+    var decoder = _StringDecoders.decoder(encoding);
     List<int> bytes = readAsBytesSync();
     decoder.write(bytes);
     return _getDecodedLines(decoder);
   }
 
   String get name() => _name;
 
   void set onError(void handler(String error)) {
     _onError = handler;
   }
@@ skipping 204 matching lines @@
     if (index != 0) {
       throw new IndexOutOfRangeException(index);
     }
     int result = _FileUtils.writeList(_id, buffer, offset, bytes);
     if (result == -1) {
       throw new FileIOException("writeList failed");
     }
     return result;
   }
 
-  void writeString(String string) {
+  void writeString(String string, [Encoding encoding = Encoding.UTF_8]) {
     _ensureFileService();
     _asyncUsed = true;
     List request = new List(3);
     request[0] = _FileUtils.kWriteStringRequest;
     request[1] = _id;
     request[2] = string;
     _writeEnqueued();
     _fileService.call(request).receive((result, replyTo) {
       _writeCompleted();
       if (result == -1 && _onError !== null) {
         _onError("writeString failed");
       }
     });
   }
 
-  int writeStringSync(String string) {
+  int writeStringSync(String string, [Encoding encoding = Encoding.UTF_8]) {
     if (_asyncUsed) {
       throw new FileIOException(
           "Mixed use of synchronous and asynchronous API");
     }
     int result = _FileUtils.checkedWriteString(_id, string);
     if (result == -1) {
       throw new FileIOException("writeString failed");
     }
     return result;
   }
@@ skipping 175 matching lines @@
   bool _asyncUsed;
   int _pendingWrites = 0;
 
   SendPort _fileService;
 
   Timer _noPendingWriteTimer;
 
   Function _onNoPendingWrites;
   Function _onError;
 }