Roll Observatory packages and add a roll script

path/lib/src/style/windows.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.
-
-library path.style.windows;
-
-import '../characters.dart' as chars;
-import '../internal_style.dart';
-import '../parsed_path.dart';
-import '../utils.dart';
-
-/// The style for Windows paths.
-class WindowsStyle extends InternalStyle {
-  WindowsStyle();
-
-  final name = 'windows';
-  final separator = '\\';
-  final separators = const ['/', '\\'];
-
-  // Deprecated properties.
-
-  final separatorPattern = new RegExp(r'[/\\]');
-  final needsSeparatorPattern = new RegExp(r'[^/\\]$');
-  final rootPattern = new RegExp(r'^(\\\\[^\\]+\\[^\\/]+|[a-zA-Z]:[/\\])');
-  final relativeRootPattern = new RegExp(r"^[/\\](?![/\\])");
-
-  bool containsSeparator(String path) => path.contains('/');
-
-  bool isSeparator(int codeUnit) =>
-      codeUnit == chars.SLASH || codeUnit == chars.BACKSLASH;
-
-  bool needsSeparator(String path) {
-    if (path.isEmpty) return false;
-    return !isSeparator(path.codeUnitAt(path.length - 1));
-  }
-
-  int rootLength(String path) {
-    if (path.isEmpty) return 0;
-    if (path.codeUnitAt(0) == chars.SLASH) return 1;
-    if (path.codeUnitAt(0) == chars.BACKSLASH) {
-      if (path.length < 2 || path.codeUnitAt(1) != chars.BACKSLASH) return 1;
-      // The path is a network share. Search for up to two '\'s, as they are
-      // the server and share - and part of the root part.
-      var index = path.indexOf('\\', 2);
-      if (index > 0) {
-        index = path.indexOf('\\', index + 1);
-        if (index > 0) return index;
-      }
-      return path.length;
-    }
-    // If the path is of the form 'C:/' or 'C:\', with C being any letter, it's
-    // a root part.
-    if (path.length < 3) return 0;
-    // Check for the letter.
-    if (!isAlphabetic(path.codeUnitAt(0))) return 0;
-    // Check for the ':'.
-    if (path.codeUnitAt(1) != chars.COLON) return 0;
-    // Check for either '/' or '\'.
-    if (!isSeparator(path.codeUnitAt(2))) return 0;
-    return 3;
-  }
-
-  bool isRootRelative(String path) => rootLength(path) == 1;
-
-  String getRelativeRoot(String path) {
-    var length = rootLength(path);
-    if (length == 1) return path[0];
-    return null;
-  }
-
-  String pathFromUri(Uri uri) {
-    if (uri.scheme != '' && uri.scheme != 'file') {
-      throw new ArgumentError("Uri $uri must have scheme 'file:'.");
-    }
-
-    var path = uri.path;
-    if (uri.host == '') {
-      // Drive-letter paths look like "file:///C:/path/to/file". The
-      // replaceFirst removes the extra initial slash.
-      if (path.startsWith('/')) path = path.replaceFirst("/", "");
-    } else {
-      // Network paths look like "file://hostname/path/to/file".
-      path = '\\\\${uri.host}$path';
-    }
-    return Uri.decodeComponent(path.replaceAll("/", "\\"));
-  }
-
-  Uri absolutePathToUri(String path) {
-    var parsed = new ParsedPath.parse(path, this);
-    if (parsed.root.startsWith(r'\\')) {
-      // Network paths become "file://server/share/path/to/file".
-
-      // The root is of the form "\\server\share". We want "server" to be the
-      // URI host, and "share" to be the first element of the path.
-      var rootParts = parsed.root.split('\\').where((part) => part != '');
-      parsed.parts.insert(0, rootParts.last);
-
-      if (parsed.hasTrailingSeparator) {
-        // If the path has a trailing slash, add a single empty component so the
-        // URI has a trailing slash as well.
-        parsed.parts.add("");
-      }
-
-      return new Uri(
-          scheme: 'file', host: rootParts.first, pathSegments: parsed.parts);
-    } else {
-      // Drive-letter paths become "file:///C:/path/to/file".
-
-      // If the path is a bare root (e.g. "C:\"), [parsed.parts] will currently
-      // be empty. We add an empty component so the URL constructor produces
-      // "file:///C:/", with a trailing slash. We also add an empty component if
-      // the URL otherwise has a trailing slash.
-      if (parsed.parts.length == 0 || parsed.hasTrailingSeparator) {
-        parsed.parts.add("");
-      }
-
-      // Get rid of the trailing "\" in "C:\" because the URI constructor will
-      // add a separator on its own.
-      parsed.parts.insert(
-          0, parsed.root.replaceAll("/", "").replaceAll("\\", ""));
-
-      return new Uri(scheme: 'file', pathSegments: parsed.parts);
-    }
-  }
-}