Migrate dart2js stubs for dart:io

tool/input_sdk/lib/io/string_transformer.dart

+// 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.io;
+
+/// The current system encoding.
+///
+/// This us used for converting from bytes to/from String when
+/// communicating on stdin, stdout and stderr.
+///
+/// On Windows this will use the currently active code page for the
+/// conversion. On all other systems it will always use UTF-8.
+const SystemEncoding SYSTEM_ENCODING = const SystemEncoding();
+
+/**
+ * The system encoding is the current code page on Windows and UTF-8 on
+ * Linux and Mac.
+ */
+class SystemEncoding extends Encoding {
+  const SystemEncoding();
+
+  String get name => 'system';
+
+  List<int> encode(String input) => encoder.convert(input);
+  String decode(List<int> encoded) => decoder.convert(encoded);
+
+  Converter<String, List<int>> get encoder {
+    if (Platform.operatingSystem == "windows") {
+      return const _WindowsCodePageEncoder();
+    } else {
+      return const Utf8Encoder();
+    }
+  }
+
+  Converter<List<int>, String> get decoder {
+    if (Platform.operatingSystem == "windows") {
+      return const _WindowsCodePageDecoder();
+    } else {
+      return const Utf8Decoder();
+    }
+  }
+}
+
+class _WindowsCodePageEncoder extends Converter<String, List<int>> {
+
+  const _WindowsCodePageEncoder();
+
+  List<int> convert(String input) {
+    List<int> encoded = _encodeString(input);
+    if (encoded == null) {
+      throw new FormatException("Invalid character for encoding");
+    }
+    return encoded;
+  }
+
+  /**
+   * Starts a chunked conversion.
+   */
+  StringConversionSink startChunkedConversion(Sink<List<int>> sink) {
+    return new _WindowsCodePageEncoderSink(sink);
+  }
+
+  external static List<int> _encodeString(String string);
+}
+
+class _WindowsCodePageEncoderSink extends StringConversionSinkBase {
+  // TODO(floitsch): provide more efficient conversions when the input is
+  // not a String.
+
+  final Sink<List<int>> _sink;
+
+  _WindowsCodePageEncoderSink(this._sink);
+
+  void close() {
+    _sink.close();
+  }
+
+  void add(String string) {
+    List<int> encoded = _WindowsCodePageEncoder._encodeString(string);
+    if (encoded == null) {
+      throw new FormatException("Invalid character for encoding");
+    }
+    _sink.add(encoded);
+  }
+
+  void addSlice(String source, int start, int end, bool isLast) {
+    if (start != 0 || end != source.length) {
+      source = source.substring(start, end);
+    }
+    add(source);
+    if (isLast) close();
+  }
+}
+
+
+class _WindowsCodePageDecoder extends Converter<List<int>, String> {
+
+  const _WindowsCodePageDecoder();
+
+  String convert(List<int> input) {
+    return _decodeBytes(input);
+  }
+
+  /**
+   * Starts a chunked conversion.
+   */
+  ByteConversionSink startChunkedConversion(Sink<String> sink) {
+    return new _WindowsCodePageDecoderSink(sink);
+  }
+
+  external static String _decodeBytes(List<int> bytes);
+}
+
+class _WindowsCodePageDecoderSink extends ByteConversionSinkBase {
+  // TODO(floitsch): provide more efficient conversions when the input is
+  // a slice.
+
+  final Sink<String> _sink;
+
+  _WindowsCodePageDecoderSink(this._sink);
+
+  void close() {
+    _sink.close();
+  }
+
+  void add(List<int> bytes) {
+    _sink.add(_WindowsCodePageDecoder._decodeBytes(bytes));
+  }
+}