Use patching for dart:io.

runtime/bin/path_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 _Path implements Path {
-  final String _path;
-
-  _Path(String source) : _path = source;
-  _Path.fromNative(String source) : _path = _clean(source);
-
-  int get hashCode => _path.hashCode;
-
-  static String _clean(String source) {
-    switch (Platform.operatingSystem) {
-      case 'windows':
-        return _cleanWindows(source);
-      default:
-        return source;
-    }
-  }
-
-  static String _cleanWindows(source) {
-    // Change \ to /.
-    var clean = source.replaceAll('\\', '/');
-    // Add / before intial [Drive letter]:
-    if (clean.length >= 2 && clean[1] == ':') {
-      clean = '/$clean';
-    }
-    return clean;
-  }
-
-  bool get isEmpty => _path.isEmpty;
-  bool get isAbsolute => _path.startsWith('/');
-  bool get hasTrailingSeparator => _path.endsWith('/');
-
-  String toString() => _path;
-
-  Path relativeTo(Path base) {
-    // Throws exception if an unimplemented or impossible case is reached.
-    // Returns a path "relative" such that
-    //    base.join(relative) == this.canonicalize.
-    // Throws an exception if no such path exists, or the case is not
-    // implemented yet.
-    var basePath = base.toString();
-    if (base.isAbsolute && _path.startsWith(basePath)) {
-      if (_path == basePath) return new Path('.');
-      if (base.hasTrailingSeparator) {
-        return new Path(_path.substring(basePath.length));
-      }
-      if (_path[basePath.length] == '/') {
-        return new Path(_path.substring(basePath.length + 1));
-      }
-    } else if (base.isAbsolute && isAbsolute) {
-      List<String> baseSegments = base.canonicalize().segments();
-      List<String> pathSegments = canonicalize().segments();
-      int common = 0;
-      int length = min(pathSegments.length, baseSegments.length);
-      while (common < length && pathSegments[common] == baseSegments[common]) {
-        common++;
-      }
-      final sb = new StringBuffer();
-
-      for (int i = common + 1; i < baseSegments.length; i++) {
-        sb.add('../');
-      }
-      if (base.hasTrailingSeparator) {
-        sb.add('../');
-      }
-      for (int i = common; i < pathSegments.length - 1; i++) {
-        sb.add('${pathSegments[i]}/');
-      }
-      sb.add('${pathSegments.last}');
-      if (hasTrailingSeparator) {
-        sb.add('/');
-      }
-      return new Path(sb.toString());
-    }
-    throw new NotImplementedException(
-      "Unimplemented case of Path.relativeTo(base):\n"
-      "  Only absolute paths are handled at present.\n"
-      "  Arguments: $_path.relativeTo($base)");
-  }
-
-  Path join(Path further) {
-    if (further.isAbsolute) {
-      throw new ArgumentError(
-          "Path.join called with absolute Path as argument.");
-    }
-    if (isEmpty) {
-      return further.canonicalize();
-    }
-    if (hasTrailingSeparator) {
-      return new Path('$_path${further}').canonicalize();
-    }
-    return new Path('$_path/${further}').canonicalize();
-  }
-
-  // Note: The URI RFC names for these operations are normalize, resolve, and
-  // relativize.
-  Path canonicalize() {
-    if (isCanonical) return this;
-    return makeCanonical();
-  }
-
-  bool get isCanonical {
-    // Contains no consecutive path separators.
-    // Contains no segments that are '.'.
-    // Absolute paths have no segments that are '..'.
-    // All '..' segments of a relative path are at the beginning.
-    if (isEmpty) return false;  // The canonical form of '' is '.'.
-    if (_path == '.') return true;
-    List segs = _path.split('/');  // Don't mask the getter 'segments'.
-    if (segs[0] == '') {  // Absolute path
-      segs[0] = null;  // Faster than removeRange().
-    } else {  // A canonical relative path may start with .. segments.
-      for (int pos = 0;
-           pos < segs.length && segs[pos] == '..';
-           ++pos) {
-        segs[pos] = null;
-      }
-    }
-    if (segs.last == '') segs.removeLast();  // Path ends with /.
-    // No remaining segments can be ., .., or empty.
-    return !segs.some((s) => s == '' || s == '.' || s == '..');
-  }
-
-  Path makeCanonical() {
-    bool isAbs = isAbsolute;
-    List segs = segments();
-    String drive;
-    if (isAbs &&
-        !segs.isEmpty &&
-        segs[0].length == 2 &&
-        segs[0][1] == ':') {
-      drive = segs[0];
-      segs.removeRange(0, 1);
-    }
-    List newSegs = [];
-    for (String segment in segs) {
-      switch (segment) {
-        case '..':
-          // Absolute paths drop leading .. markers, including after a drive.
-          if (newSegs.isEmpty) {
-            if (isAbs) {
-              // Do nothing: drop the segment.
-            } else {
-              newSegs.add('..');
-            }
-          } else if (newSegs.last == '..') {
-            newSegs.add('..');
-          } else {
-            newSegs.removeLast();
-          }
-          break;
-        case '.':
-        case '':
-          // Do nothing - drop the segment.
-          break;
-        default:
-          newSegs.add(segment);
-          break;
-      }
-    }
-
-    List segmentsToJoin = [];
-    if (isAbs) {
-      segmentsToJoin.add('');
-      if (drive != null) {
-        segmentsToJoin.add(drive);
-      }
-    }
-
-    if (newSegs.isEmpty) {
-      if (isAbs) {
-        segmentsToJoin.add('');
-      } else {
-        segmentsToJoin.add('.');
-      }
-    } else {
-      segmentsToJoin.addAll(newSegs);
-      if (hasTrailingSeparator) {
-        segmentsToJoin.add('');
-      }
-    }
-    return new Path(Strings.join(segmentsToJoin, '/'));
-  }
-
-  String toNativePath() {
-    if (Platform.operatingSystem == 'windows') {
-      String nativePath = _path;
-      // Drop '/' before a drive letter.
-      if (nativePath.length > 3 &&
-          nativePath.startsWith('/') &&
-          nativePath[2] == ':') {
-        nativePath = nativePath.substring(1);
-      }
-      nativePath = nativePath.replaceAll('/', '\\');
-      return nativePath;
-    }
-    return _path;
-  }
-
-  List<String> segments() {
-    List result = _path.split('/');
-    if (isAbsolute) result.removeRange(0, 1);
-    if (hasTrailingSeparator) result.removeLast();
-    return result;
-  }
-
-  Path append(String finalSegment) {
-    if (isEmpty) {
-      return new Path(finalSegment);
-    } else if (hasTrailingSeparator) {
-      return new Path('$_path$finalSegment');
-    } else {
-      return new Path('$_path/$finalSegment');
-    }
-  }
-
-  String get filenameWithoutExtension {
-    var name = filename;
-    if (name == '.' || name == '..') return name;
-    int pos = name.lastIndexOf('.');
-    return (pos < 0) ? name : name.substring(0, pos);
-  }
-
-  String get extension {
-    var name = filename;
-    int pos = name.lastIndexOf('.');
-    return (pos < 0) ? '' : name.substring(pos + 1);
-  }
-
-  Path get directoryPath {
-    int pos = _path.lastIndexOf('/');
-    if (pos < 0) return new Path('');
-    while (pos > 0 && _path[pos - 1] == '/') --pos;
-    return new Path((pos > 0) ? _path.substring(0, pos) : '/');
-  }
-
-  String get filename {
-    int pos = _path.lastIndexOf('/');
-    return _path.substring(pos + 1);
-  }
-}