anchor.diff:  class _PubLocalApp extends PubApp {
     bool _activated = false;
   
  -  _PubLocalApp(String appName) : super._(appName);
  +  _PubLocalApp(String packageName) : super._(packageName);
   
     bool get isGlobal => false;
   
  -  // TODO: For now, assume that local apps are installed?
  -  bool get isActivated => true;
  +  // TODO: Implement.
  +  bool get isActivated => throw new UnsupportedError('unimplemented');
   
     void activate() { }
   
     void update() { }
   
     String run(List<String> arguments, {String script, String workingDirectory}) {
  -    return Pub.run(script == null ? appName : '${appName}:${script}',
  +    return Pub.run(packageName,
  +        script: script,
           arguments: arguments,
           workingDirectory: workingDirectory);
     }
  
positive.code:   }
  
    /// Run the given installed Dart application.
    String run(String package, {List<String> arguments, String workingDirectory}) {
      List args = ['global', 'run', package];
      if (arguments != null) args.addAll(arguments);
      return runProcess(_sdkBin('pub'), arguments: args,
          workingDirectory: workingDirectory);
  
negative.code: 
  /// A Dart command-line application, installed via `pub global activate`.
  abstract class PubApp {
    final String packageName;
  
    PubApp._(this.packageName);
  
    /// Create a new reference to a pub application; [packageName] is the same as the
    /// package name.
    factory PubApp.global(String packageName) => new _PubGlobalApp(packageName);
  
    /// Create a new reference to a pub application; [packageName] is the same as the
    /// package name.
    factory PubApp.local(String packageName) => new _PubLocalApp(packageName);
  
    bool get isGlobal;
  
  