Add a Pub source that checks packages out from Git.

utils/pub/pub.dart

Index: utils/pub/pub.dart
diff --git a/utils/pub/pub.dart b/utils/pub/pub.dart
index 45c6c9815aad625a4abd0c22919f842aea331d9e..23037fef81e2a7202ab0d732328cd3ab222bd37d 100644
--- a/utils/pub/pub.dart
+++ b/utils/pub/pub.dart
@@ -20,7 +20,9 @@
 #source('command_version.dart');
 #source('package.dart');
 #source('source.dart');
+#source('source_registry.dart');
 #source('sdk_source.dart');
+#source('git_source.dart');
 
 main() {
   final args = new Options().arguments;
@@ -72,8 +74,9 @@ main() {
 
   // TODO(rnystrom): Do we want this to be global?

[Bob Nystrom, 2012/05/08 17:01:49]

If you don't mind, remove this TODO. I think we've decided we don't. :)

[nweiz, 2012/05/09 00:21:04]

Done.

   final cache = new SystemCache(cacheDir);
-
-  Source.defaultSource = new SdkSource(sdkDir);
+  cache.sources.register(new SdkSource(sdkDir));
+  cache.sources.register(new GitSource());
+  cache.sources.setDefault('sdk');
 
   // Select the command.
   final command = commands[args[0]];
@@ -137,7 +140,7 @@ class PubCommand {
     // TODO(rnystrom): Will eventually need better logic to walk up
     // subdirectories until we hit one that looks package-like. For now, just
     // assume the cwd is it.
-    Package.load(workingDir).then((pkg) {
+    Package.load(workingDir, cache.sources).then((pkg) {
       packagesDir = new PackagesDir(pkg, cache);
       onRun();
     });