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

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

Index: sdk/lib/_internal/pub_generated/lib/src/source.dart
diff --git a/sdk/lib/_internal/pub_generated/lib/src/source.dart b/sdk/lib/_internal/pub_generated/lib/src/source.dart
deleted file mode 100644
index d7b00f1adbc13f51382da2eaab226cf9489822ac..0000000000000000000000000000000000000000
--- a/sdk/lib/_internal/pub_generated/lib/src/source.dart
+++ /dev/null
@@ -1,187 +0,0 @@
-// 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.
-
-library pub.source;
-
-import 'dart:async';
-
-import 'package:pub_semver/pub_semver.dart';
-
-import 'package.dart';
-import 'pubspec.dart';
-import 'system_cache.dart';
-
-/// A source from which to get packages.
-///
-/// Each source has many packages that it looks up using [PackageId]s. Sources
-/// that inherit this directly (currently just [PathSource]) are *uncached*
-/// sources. They deliver a package directly to the package that depends on it.
-///
-/// Other sources are *cached* sources. These extend [CachedSource]. When a
-/// package needs a dependency from a cached source, it is first installed in
-/// the [SystemCache] and then acquired from there.
-abstract class Source {
-  /// The name of the source.
-  ///
-  /// Should be lower-case, suitable for use in a filename, and unique accross
-  /// all sources.
-  String get name;
-
-  /// Whether this source can choose between multiple versions of the same
-  /// package during version solving.
-  ///
-  /// Defaults to `false`.
-  final bool hasMultipleVersions = false;
-
-  /// Whether or not this source is the default source.
-  bool get isDefault => systemCache.sources.defaultSource == this;
-
-  /// The system cache with which this source is registered.
-  SystemCache get systemCache {
-    assert(_systemCache != null);
-    return _systemCache;
-  }
-
-  /// The system cache variable.
-  ///
-  /// Set by [_bind].
-  SystemCache _systemCache;
-
-  /// Records the system cache to which this source belongs.
-  ///
-  /// This should only be called once for each source, by
-  /// [SystemCache.register]. It should not be overridden by base classes.
-  void bind(SystemCache systemCache) {
-    assert(_systemCache == null);
-    this._systemCache = systemCache;
-  }
-
-  /// Get the list of all versions that exist for the package described by
-  /// [description].
-  ///
-  /// [name] is the expected name of the package.
-  ///
-  /// Note that this does *not* require the packages to be downloaded locally,
-  /// which is the point. This is used during version resolution to determine
-  /// which package versions are available to be downloaded (or already
-  /// downloaded).
-  ///
-  /// By default, this assumes that each description has a single version and
-  /// uses [describe] to get that version.
-  Future<List<Version>> getVersions(String name, description) {
-    var id = new PackageId(name, this.name, Version.none, description);
-    return describe(id).then((pubspec) => [pubspec.version]);
-  }
-
-  /// Loads the (possibly remote) pubspec for the package version identified by
-  /// [id].
-  ///
-  /// This may be called for packages that have not yet been downloaded during
-  /// the version resolution process.
-  ///
-  /// Sources should not override this. Instead, they implement [doDescribe].
-  Future<Pubspec> describe(PackageId id) {
-    if (id.isRoot) throw new ArgumentError("Cannot describe the root package.");
-    if (id.source != name) {
-      throw new ArgumentError("Package $id does not use source $name.");
-    }
-
-    // Delegate to the overridden one.
-    return doDescribe(id);
-  }
-
-  /// Loads the (possibly remote) pubspec for the package version identified by
-  /// [id].
-  ///
-  /// This may be called for packages that have not yet been downloaded during
-  /// the version resolution process.
-  ///
-  /// This method is effectively protected: subclasses must implement it, but
-  /// external code should not call this. Instead, call [describe].
-  Future<Pubspec> doDescribe(PackageId id);
-
-  /// Ensures [id] is available locally and creates a symlink at [symlink]
-  /// pointing it.
-  Future get(PackageId id, String symlink);
-
-  /// Returns the directory where this package can (or could) be found locally.
-  ///
-  /// If the source is cached, this will be a path in the system cache. In that
-  /// case, this will return a directory even if the package has not been
-  /// installed into the cache yet.
-  Future<String> getDirectory(PackageId id);
-
-  /// Gives the source a chance to interpret and validate the description for
-  /// a package coming from this source.
-  ///
-  /// When a [Pubspec] or [LockFile] is parsed, it reads in the description for
-  /// each dependency. It is up to the dependency's [Source] to determine how
-  /// that should be interpreted. This will be called during parsing to validate
-  /// that the given [description] is well-formed according to this source, and
-  /// to give the source a chance to canonicalize the description.
-  ///
-  /// [containingPath] is the path to the local file (pubspec or lockfile)
-  /// where this description appears. It may be `null` if the description is
-  /// coming from some in-memory source (such as pulling down a pubspec from
-  /// pub.dartlang.org).
-  ///
-  /// It should return if a (possibly modified) valid description, or throw a
-  /// [FormatException] if not valid.
-  ///
-  /// [fromLockFile] is true when the description comes from a [LockFile], to
-  /// allow the source to use lockfile-specific descriptions via [resolveId].
-  dynamic parseDescription(String containingPath, description,
-      {bool fromLockFile: false});
-
-  /// When a [LockFile] is serialized, it uses this method to get the
-  /// [description] in the right format.
-  ///
-  /// [containingPath] is the containing directory of the root package.
-  dynamic serializeDescription(String containingPath, description) {
-    return description;
-  }
-
-  /// When a package [description] is shown to the user, this is called to
-  /// convert it into a human-friendly form.
-  ///
-  /// By default, it just converts the description to a string, but sources
-  /// may customize this. [containingPath] is the containing directory of the
-  /// root package.
-  String formatDescription(String containingPath, description) {
-    return description.toString();
-  }
-
-  /// Returns whether or not [description1] describes the same package as
-  /// [description2] for this source.
-  ///
-  /// This method should be light-weight. It doesn't need to validate that
-  /// either package exists.
-  bool descriptionsEqual(description1, description2);
-
-  /// Resolves [id] to a more possibly more precise that will uniquely identify
-  /// a package regardless of when the package is requested.
-  ///
-  /// For some sources, [PackageId]s can point to different chunks of code at
-  /// different times. This takes such an [id] and returns a future that
-  /// completes to a [PackageId] that will uniquely specify a single chunk of
-  /// code forever.
-  ///
-  /// For example, [GitSource] might take an [id] with description
-  /// `http://github.com/dart-lang/some-lib.git` and return an id with a
-  /// description that includes the current commit of the Git repository.
-  ///
-  /// Pub calls this after getting a package, so the source can use the local
-  /// package to determine information about the resolved id.
-  ///
-  /// The returned [PackageId] may have a description field that's invalid
-  /// according to [parseDescription], although it must still be serializable
-  /// to JSON and YAML. It must also be equal to [id] according to
-  /// [descriptionsEqual].
-  ///
-  /// By default, this just returns [id].
-  Future<PackageId> resolveId(PackageId id) => new Future.value(id);
-
-  /// Returns the source's name.
-  String toString() => name;
-}