Revert "Revert "Use native async/await support in pub.""

sdk/lib/_internal/pub_generated/lib/src/source/path.dart

Index: sdk/lib/_internal/pub_generated/lib/src/source/path.dart
diff --git a/sdk/lib/_internal/pub_generated/lib/src/source/path.dart b/sdk/lib/_internal/pub_generated/lib/src/source/path.dart
deleted file mode 100644
index d6f7b8c0c70a9ce04e576216835edb1cc805533e..0000000000000000000000000000000000000000
--- a/sdk/lib/_internal/pub_generated/lib/src/source/path.dart
+++ /dev/null
@@ -1,162 +0,0 @@
-// 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 pub.source.path;
-
-import 'dart:async';
-
-import 'package:path/path.dart' as p;
-
-import '../exceptions.dart';
-import '../io.dart';
-import '../package.dart';
-import '../pubspec.dart';
-import '../source.dart';
-import '../utils.dart';
-
-/// A package [Source] that gets packages from a given local file path.
-class PathSource extends Source {
-  /// Returns a valid description for a reference to a package at [path].
-  static describePath(String path) {
-    return {
-      "path": path,
-      "relative": p.isRelative(path)
-    };
-  }
-
-  /// Given a valid path reference description, returns the file path it
-  /// describes.
-  ///
-  /// This returned path may be relative or absolute and it is up to the caller
-  /// to know how to interpret a relative path.
-  static String pathFromDescription(description) => description["path"];
-
-  final name = 'path';
-
-  Future<Pubspec> doDescribe(PackageId id) {
-    return new Future.sync(() {
-      var dir = _validatePath(id.name, id.description);
-      return new Pubspec.load(dir, systemCache.sources, expectedName: id.name);
-    });
-  }
-
-  bool descriptionsEqual(description1, description2) {
-    // Compare real paths after normalizing and resolving symlinks.
-    var path1 = canonicalize(description1["path"]);
-    var path2 = canonicalize(description2["path"]);
-    return path1 == path2;
-  }
-
-  Future get(PackageId id, String symlink) {
-    return new Future.sync(() {
-      var dir = _validatePath(id.name, id.description);
-      createPackageSymlink(
-          id.name,
-          dir,
-          symlink,
-          relative: id.description["relative"]);
-    });
-  }
-
-  Future<String> getDirectory(PackageId id) =>
-      newFuture(() => _validatePath(id.name, id.description));
-
-  /// Parses a path dependency.
-  ///
-  /// This takes in a path string and returns a map. The "path" key will be the
-  /// original path but resolved relative to the containing path. The
-  /// "relative" key will be `true` if the original path was relative.
-  ///
-  /// A path coming from a pubspec is a simple string. From a lock file, it's
-  /// an expanded {"path": ..., "relative": ...} map.
-  dynamic parseDescription(String containingPath, description,
-      {bool fromLockFile: false}) {
-    if (fromLockFile) {
-      if (description is! Map) {
-        throw new FormatException("The description must be a map.");
-      }
-
-      if (description["path"] is! String) {
-        throw new FormatException(
-            "The 'path' field of the description must " "be a string.");
-      }
-
-      if (description["relative"] is! bool) {
-        throw new FormatException(
-            "The 'relative' field of the description " "must be a boolean.");
-      }
-
-      return description;
-    }
-
-    if (description is! String) {
-      throw new FormatException("The description must be a path string.");
-    }
-
-    // Resolve the path relative to the containing file path, and remember
-    // whether the original path was relative or absolute.
-    var isRelative = p.isRelative(description);
-    if (isRelative) {
-      // Relative paths coming from pubspecs that are not on the local file
-      // system aren't allowed. This can happen if a hosted or git dependency
-      // has a path dependency.
-      if (containingPath == null) {
-        throw new FormatException(
-            '"$description" is a relative path, but this ' 'isn\'t a local pubspec.');
-      }
-
-      description = p.normalize(p.join(p.dirname(containingPath), description));
-    }
-
-    return {
-      "path": description,
-      "relative": isRelative
-    };
-  }
-
-  /// Serializes path dependency's [description].
-  ///
-  /// For the descriptions where `relative` attribute is `true`, tries to make
-  /// `path` relative to the specified [containingPath].
-  dynamic serializeDescription(String containingPath, description) {
-    if (description["relative"]) {
-      return {
-        "path": p.relative(description['path'], from: containingPath),
-        "relative": true
-      };
-    }
-    return description;
-  }
-
-  /// Converts a parsed relative path to its original relative form.
-  String formatDescription(String containingPath, description) {
-    var sourcePath = description["path"];
-    if (description["relative"]) {
-      sourcePath = p.relative(description['path'], from: containingPath);
-    }
-
-    return sourcePath;
-  }
-
-  /// Ensures that [description] is a valid path description and returns a
-  /// normalized path to the package.
-  ///
-  /// It must be a map, with a "path" key containing a path that points to an
-  /// existing directory. Throws an [ApplicationException] if the path is
-  /// invalid.
-  String _validatePath(String name, description) {
-    var dir = description["path"];
-
-    if (dirExists(dir)) return dir;
-
-    if (fileExists(dir)) {
-      fail(
-          'Path dependency for package $name must refer to a directory, '
-              'not a file. Was "$dir".');
-    }
-
-    throw new PackageNotFoundException(
-        'Could not find package $name at "$dir".');
-  }
-}