Validate packages against their SDK constraints.

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';
@@ skipping 42 matching lines @@
       return _clone(_repoCachePath(id), revisionCachePath, mirror: false);
     }).then((_) {
       var ref = _getEffectiveRef(id);
       if (ref == 'HEAD') return;
       return _checkOut(revisionCachePath, ref);
     }).then((_) {
       return Package.load(id.name, revisionCachePath, systemCache.sources);
     });
   }
 
+  Future<String> systemCacheDirectory(PackageId id) => _revisionCachePath(id);
+
   /// 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 "
           "with a 'url' key.");
     }
     description = new Map.from(description);
     description.remove('url');
@@ skipping 118 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;
   }
 }