Improve the detection lockfile freshness.

lib/src/global_packages.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 pub.global_packages;
 
 import 'dart:async';
 import 'dart:io';
 
 import 'package:path/path.dart' as p;
@@ skipping 150 matching lines @@
       // If the package specified by the user doesn't exist, we want to
       // surface that as a [DataError] with the associated exit code.
       if (result.error.package != dep.name) throw result.error;
       if (result.error is NoVersionException) dataError(result.error.message);
       throw result.error;
     }
     result.showReport(SolveType.GET);
 
     // Make sure all of the dependencies are locally installed.
     await Future.wait(result.packages.map(_cacheDependency));
-    var lockFile = new LockFile(result.packages, cache.sources);
 
     // Load the package graph from [result] so we don't need to re-parse all
     // the pubspecs.
     var entrypoint = new Entrypoint.fromSolveResult(root, cache, result,
         isGlobal: true);
     var snapshots = await _precompileExecutables(entrypoint, dep.name);
+
+    var lockFile = result.lockFile;
     _writeLockFile(dep.name, lockFile);
     writeTextFile(_getPackagesFilePath(dep.name), lockFile.packagesFile());
 
     _updateBinStubs(entrypoint.packageGraph.packages[dep.name], executables,
         overwriteBinStubs: overwriteBinStubs, snapshots: snapshots);
   }
 
   /// Precompiles the executables for [package] and saves them in the global
   /// cache.
   ///
@@ skipping 114 matching lines @@
     // could find and load the [Package] object, but normally an entrypoint
     // doesn't expect to be in its own lockfile.
     var id = lockFile.packages[name];
     lockFile = lockFile.removePackage(name);
 
     var source = cache.sources[id.source];
     var entrypoint;
     if (source is CachedSource) {
       // For cached sources, the package itself is in the cache and the
       // lockfile is the one we just loaded.
-      var dir = cache.sources[id.source].getDirectory(id);
-      var package = new Package.load(name, dir, cache.sources);
       entrypoint = new Entrypoint.inMemory(
-          package, lockFile, cache, isGlobal: true);
+          cache.sources.load(id), lockFile, cache, isGlobal: true);
     } else {
       // For uncached sources (i.e. path), the ID just points to the real
       // directory for the package.
       assert(id.source == "path");
       entrypoint = new Entrypoint(
           PathSource.pathFromDescription(id.description), cache,
           isGlobal: true);
     }
 
     if (entrypoint.root.pubspec.environment.sdkVersion.allows(sdk.version)) {
@@ skipping 465 matching lines @@
   }
 
   /// Returns the value of the property named [name] in the bin stub script
   /// [source].
   String _binStubProperty(String source, String name) {
     var pattern = new RegExp(quoteRegExp(name) + r": ([a-zA-Z0-9_-]+)");
     var match = pattern.firstMatch(source);
     return match == null ? null : match[1];
   }
 }