Big merge from experimental to bleeding edge.

utils/pub/git_source.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.
 
 library git_source;
 
+import 'dart:async';
 import 'git.dart' as git;
 import 'io.dart';
 import 'package.dart';
 import 'source.dart';
 import 'source_registry.dart';
 import 'utils.dart';
 
 /// A package source that installs packages from Git repos.
 class GitSource extends Source {
   final String name = "git";
@@ skipping 10 matching lines @@
   /// linked to from the `packages/` directory.
   ///
   /// In addition, the Git system cache contains a subdirectory named `cache/`
   /// which contains a directory for each separate repository URL, named
   /// `<package name>-<url hash>`. These are used to check out the repository
   /// itself; each of the commit-specific directories are clones of a directory
   /// in `cache/`.
   Future<Package> installToSystemCache(PackageId id) {
     var revisionCachePath;
 
-    return git.isInstalled.chain((installed) {
+    return git.isInstalled.then((installed) {
       if (!installed) {
         throw new Exception(
             "Cannot install '${id.name}' from Git (${_getUrl(id)}).\n"
             "Please ensure Git is correctly installed.");
       }
 
       return ensureDir(join(systemCacheRoot, 'cache'));
-    }).chain((_) => _ensureRepoCache(id))
-      .chain((_) => _revisionCachePath(id))
-      .chain((path) {
+    }).then((_) => _ensureRepoCache(id))
+      .then((_) => _revisionCachePath(id))
+      .then((path) {
       revisionCachePath = path;
       return exists(revisionCachePath);
-    }).chain((exists) {
+    }).then((exists) {
       if (exists) return new Future.immediate(null);
       return _clone(_repoCachePath(id), revisionCachePath, mirror: false);
-    }).chain((_) {
+    }).then((_) {
       var ref = _getEffectiveRef(id);
       if (ref == 'HEAD') return new Future.immediate(null);
       return _checkOut(revisionCachePath, ref);
-    }).chain((_) {
+    }).then((_) {
       return Package.load(id.name, revisionCachePath, systemCache.sources);
     });
   }
 
   /// Ensures [description] is a Git URL.
   void validateDescription(description, {bool fromLockFile: false}) {
     // A single string is assumed to be a Git URL.
     if (description is String) return;
     if (description is! Map || !description.containsKey('url')) {
       throw new FormatException("The description must be a Git URL or a map "
@@ skipping 16 matching lines @@
   bool descriptionsEqual(description1, description2) {
     // TODO(nweiz): Do we really want to throw an error if you have two
     // dependencies on some repo, one of which specifies a ref and one of which
     // doesn't? If not, how do we handle that case in the version solver?
     return _getUrl(description1) == _getUrl(description2) &&
       _getRef(description1) == _getRef(description2);
   }
 
   /// Attaches a specific commit to [id] to disambiguate it.
   Future<PackageId> resolveId(PackageId id) {
-    return _revisionAt(id).transform((revision) {
+    return _revisionAt(id).then((revision) {
       var description = {'url': _getUrl(id), 'ref': _getRef(id)};
       description['resolved-ref'] = revision;
       return new PackageId(id.name, this, id.version, description);
     });
   }
 
   /// Ensure that the canonical clone of the repository referred to by [id] (the
   /// one in `<system cache>/git/cache`) exists and is up-to-date. Returns a
   /// future that completes once this is finished and throws an exception if it
   /// fails.
   Future _ensureRepoCache(PackageId id) {
     var path = _repoCachePath(id);
-    return exists(path).chain((exists) {
+    return exists(path).then((exists) {
       if (!exists) return _clone(_getUrl(id), path, mirror: true);
 
-      return git.run(["fetch"], workingDir: path).transform((result) => null);
+      return git.run(["fetch"], workingDir: path).then((result) => null);
     });
   }
 
   /// Returns a future that completes to the revision hash of [id].
   Future<String> _revisionAt(PackageId id) {
     return git.run(["rev-parse", _getEffectiveRef(id)],
-        workingDir: _repoCachePath(id)).transform((result) => result[0]);
+        workingDir: _repoCachePath(id)).then((result) => result[0]);
   }
 
   /// Returns the path to the revision-specific cache of [id].
   Future<String> _revisionCachePath(PackageId id) {
-    return _revisionAt(id).transform((rev) {
+    return _revisionAt(id).then((rev) {
       var revisionCacheName = '${id.name}-$rev';
       return join(systemCacheRoot, revisionCacheName);
     });
   }
 
   /// Clones the repo at the URI [from] to the path [to] on the local
   /// filesystem.
   ///
   /// If [mirror] is true, create a bare, mirrored clone. This doesn't check out
   /// the working tree, but instead makes the repository a local mirror of the
   /// remote repository. See the manpage for `git clone` for more information.
   Future _clone(String from, String to, {bool mirror: false}) {
     // Git on Windows does not seem to automatically create the destination
     // directory.
-    return ensureDir(to).chain((_) {
+    return ensureDir(to).then((_) {
       var args = ["clone", from, to];
       if (mirror) args.insertRange(1, 1, "--mirror");
       return git.run(args);
-    }).transform((result) => null);
+    }).then((result) => null);
   }
 
   /// Checks out the reference [ref] in [repoPath].
   Future _checkOut(String repoPath, String ref) {
-    return git.run(["checkout", ref], workingDir: repoPath).transform(
+    return git.run(["checkout", ref], workingDir: repoPath).then(
         (result) => null);
   }
 
   /// Returns the path to the canonical clone of the repository referred to by
   /// [id] (the one in `<system cache>/git/cache`).
   String _repoCachePath(PackageId id) {
     var repoCacheName = '${id.name}-${sha1(_getUrl(id))}';
     return join(systemCacheRoot, 'cache', repoCacheName);
   }
 
@@ skipping 33 matching lines @@
     return description['ref'];
   }
 
   /// Returns [description] if it's a description, or [PackageId.description] if
   /// it's a [PackageId].
   _getDescription(description) {
     if (description is PackageId) return description.description;
     return description;
   }
 }