Roll Observatory packages and add a roll script

analyzer/lib/file_system/file_system.dart

-// Copyright (c) 2014, 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 file_system;
-
-import 'dart:async';
-
-import 'package:analyzer/src/generated/source.dart';
-import 'package:path/path.dart';
-import 'package:watcher/watcher.dart';
-
-/**
- * [File]s are leaf [Resource]s which contain data.
- */
-abstract class File extends Resource {
-  /**
-   * Watch for changes to this file
-   */
-  Stream<WatchEvent> get changes;
-
-  /**
-   * Return the last-modified stamp of the file.
-   * Throws [FileSystemException] if the file does not exist.
-   */
-  int get modificationStamp;
-
-  /**
-   * Create a new [Source] instance that serves this file.
-   */
-  Source createSource([Uri uri]);
-
-  /**
-   * Synchronously read the entire file contents as a [String].
-   * Throws [FileSystemException] if the file does not exist.
-   */
-  String readAsStringSync();
-}
-
-/**
- * Base class for all file system exceptions.
- */
-class FileSystemException implements Exception {
-  final String path;
-  final String message;
-
-  FileSystemException(this.path, this.message);
-
-  String toString() => 'FileSystemException(path=$path; message=$message)';
-}
-
-/**
- * [Folder]s are [Resource]s which may contain files and/or other folders.
- */
-abstract class Folder extends Resource {
-  /**
-   * Watch for changes to the files inside this folder (and in any nested
-   * folders, including folders reachable via links).
-   */
-  Stream<WatchEvent> get changes;
-
-  /**
-   * If the path [path] is a relative path, convert it to an absolute path
-   * by interpreting it relative to this folder.  If it is already an aboslute
-   * path, then don't change it.
-   *
-   * However, regardless of whether [path] is relative or absolute, normalize
-   * it by removing path components of the form '.' or '..'.
-   */
-  String canonicalizePath(String path);
-
-  /**
-   * Return `true` if absolute [path] references a resource in this folder.
-   */
-  bool contains(String path);
-
-  /**
-   * Return an existing child [Resource] with the given [relPath].
-   * Return a not existing [File] if no such child exist.
-   */
-  Resource getChild(String relPath);
-
-  /**
-   * Return a [Folder] representing a child [Resource] with the given
-   * [relPath].  This call does not check whether a folder with the given name
-   * exists on the filesystem--client must call the [Folder]'s `exists` getter
-   * to determine whether the folder actually exists.
-   */
-  Folder getChildAssumingFolder(String relPath);
-
-  /**
-   * Return a list of existing direct children [Resource]s (folders and files)
-   * in this folder, in no particular order.
-   */
-  List<Resource> getChildren();
-}
-
-/**
- * The abstract class [Resource] is an abstraction of file or folder.
- */
-abstract class Resource {
-  /**
-   * Return `true` if this resource exists.
-   */
-  bool get exists;
-
-  /**
-   * Return the [Folder] that contains this resource, or `null` if this resource
-   * is a root folder.
-   */
-  Folder get parent;
-
-  /**
-   * Return the full path to this resource.
-   */
-  String get path;
-
-  /**
-   * Return a short version of the name that can be displayed to the user to
-   * denote this resource.
-   */
-  String get shortName;
-
-  /**
-   * Return `true` if absolute [path] references this resource or a resource in
-   * this folder.
-   */
-  bool isOrContains(String path);
-}
-
-/**
- * Instances of the class [ResourceProvider] convert [String] paths into
- * [Resource]s.
- */
-abstract class ResourceProvider {
-  /**
-   * Get the path context used by this resource provider.
-   */
-  Context get pathContext;
-
-  /**
-   * Return a [File] that corresponds to the given [path].
-   * 
-   * A file may or may not exist at this location.
-   */
-  File getFile(String path);
-
-  /**
-   * Return a [Folder] that corresponds to the given [path].
-   * 
-   * A folder may or may not exist at this location.
-   */
-  Folder getFolder(String path);
-
-  /**
-   * Return the [Resource] that corresponds to the given [path].
-   */
-  Resource getResource(String path);
-
-  /**
-   * Return the folder in which the plugin with the given [pluginId] can store
-   * state that will persist across sessions. The folder returned for a given id
-   * will not be returned for a different id, ensuring that plugins do not need
-   * to be concerned with file name collisions with other plugins, assuming that
-   * the plugin ids are unique. The plugin ids must be valid folder names.
-   */
-  Folder getStateLocation(String pluginId);
-}
-
-/**
- * A [UriResolver] for [Resource]s.
- */
-class ResourceUriResolver extends UriResolver {
-  /**
-   * The name of the `file` scheme.
-   */
-  static String _FILE_SCHEME = "file";
-
-  final ResourceProvider _provider;
-
-  ResourceUriResolver(this._provider);
-
-  @override
-  Source resolveAbsolute(Uri uri) {
-    if (!_isFileUri(uri)) {
-      return null;
-    }
-    Resource resource =
-        _provider.getResource(_provider.pathContext.fromUri(uri));
-    if (resource is File) {
-      return resource.createSource(uri);
-    }
-    return null;
-  }
-
-  @override
-  Uri restoreAbsolute(Source source) => source.uri;
-
-  /**
-   * Return `true` if the given [uri] is a `file` URI.
-   */
-  static bool _isFileUri(Uri uri) => uri.scheme == _FILE_SCHEME;
-}