add cache list command to pub

utils/pub/hosted_source.dart

Index: utils/pub/hosted_source.dart
===================================================================
--- utils/pub/hosted_source.dart	(revision 19836)
+++ utils/pub/hosted_source.dart	(working copy)
@@ -118,6 +118,22 @@
     return description;
   }
 
+  /// Returns a list of packages in the default cache

[Bob Nystrom, 2013/03/12 22:12:03]

Remove this comment.

[keertip, 2013/03/13 15:55:00]

Done.

+  Future<List<Package>> getCachedPackages() {
+    var url = _defaultUrl.replaceAll(new RegExp(r"^https?://"), "");

[Bob Nystrom, 2013/03/12 22:12:03]

Can you pull this out into a separate function and call it from here and line
96?

[keertip, 2013/03/13 15:55:00]

Done.

+    return listDir(path.join(systemCacheRoot,url)).then((entries){

[Bob Nystrom, 2013/03/12 22:12:03]

Space after "," and between ")" and "{".

[keertip, 2013/03/13 15:55:00]

Done.

+      var list = new List();
+      for (var entry in entries) {
+        var name = path.basename(entry).replaceAll(new RegExp(r"-(.*)"),"");

[Bob Nystrom, 2013/03/12 22:12:03]

How about:

path.basename(entry).split('-')[0];

[nweiz, 2013/03/12 22:58:48]

Both of these are dangerous if a package has a hyphen in its name. If you pass
null here, it should detect the name from the pubspec, which is safer.

+        var p = new Package.load(name, entry, systemCache.sources);
+        list.add(p);
+      }
+      return list;

[Bob Nystrom, 2013/03/12 22:12:03]

return entries.map((entry) {
  var name = ...
  return new Package.load...
});

[keertip, 2013/03/13 15:55:00]

Done.

+    }).catchError((ex) {
+      throw 'Could not list packages in pub cache ${ex}';

[Bob Nystrom, 2013/03/12 22:12:03]

Don't bother catching this.

[keertip, 2013/03/13 15:55:00]

Done.

+    });
+  }
+  
   /// When an error occurs trying to read something about [package] from [url],
   /// this tries to translate into a more user friendly error message. Always
   /// throws an error, either the original one or a better one.