Add a "pub global run" command.

sdk/lib/_internal/pub/lib/src/command.dart

 // Copyright (c) 2013, 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.command;
 
 import 'dart:async';
 import 'dart:math' as math;
 
 import 'package:args/args.dart';
 import 'package:path/path.dart' as path;
 
 import 'command/build.dart';
 import 'command/cache.dart';
 import 'command/deps.dart';
 import 'command/get.dart';
 import 'command/global.dart';
 import 'command/help.dart';
 import 'command/lish.dart';
 import 'command/list_package_dirs.dart';
 import 'command/run.dart';
 import 'command/serve.dart';
 import 'command/upgrade.dart';
 import 'command/uploader.dart';
 import 'command/version.dart';
 import 'entrypoint.dart';
 import 'exceptions.dart';
-import 'exit_codes.dart' as exit_codes;
 import 'log.dart' as log;
 import 'global_packages.dart';
 import 'system_cache.dart';
 import 'utils.dart';
 
 /// The base class for commands for the pub executable.
 ///
 /// A command may either be a "leaf" command or it may be a parent for a set
 /// of subcommands. Only leaf commands are ever actually invoked. If a command
 /// has subcommands, then one of those must always be chosen.
@@ skipping 22 matching lines @@
     buffer.writeln(
         'See http://dartlang.org/tools/pub for detailed documentation.');
 
     log.message(buffer);
   }
 
   /// Fails with a usage error [message] when trying to select from one of
   /// [commands].
   static void usageErrorWithCommands(Map<String, PubCommand> commands,
                                 String message) {
-    throw new UsageException(message, _listCommands(commands));
+    throw new UsageException(message)..bindUsage(_listCommands(commands));
   }
 
   /// Writes [commands] in a nicely formatted list to [buffer].
   static String _listCommands(Map<String, PubCommand> commands) {
     // If there are no subcommands, do nothing.
     if (commands.isEmpty) return "";
 
     // Don't include aliases.
     var names = commands.keys
         .where((name) => !commands[name].aliases.contains(name));
@@ skipping 102 matching lines @@
     _cache = new SystemCache.withSources(cacheDir, isOffline: isOffline);
     _globals = new GlobalPackages(_cache);
 
     if (requiresEntrypoint) {
       // 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.
       entrypoint = new Entrypoint(path.current, cache);
     }
 
-    return syncFuture(onRun);
+    return syncFuture(onRun).catchError((error) {
+      if (error is UsageException) error.bindUsage(_getUsage());
+      throw error;
+    });
   }
 
   /// Override this to perform the specific command.
   ///
   /// Return a future that completes when the command is done or fails if the
   /// command fails. If the command is synchronous, it may return `null`. Only
   /// leaf command should override this.
   Future onRun() {
     // Leaf commands should override this and non-leaf commands should never
     // call it.
     assert(false);
     return null;
   }
 
   /// Displays usage information for this command.
   ///
   /// If [description] is omitted, defaults to the command's description.
   void printUsage([String description]) {
     if (description == null) description = this.description;
     log.message('$description\n\n${_getUsage()}');
   }
 
-  // TODO(rnystrom): Use this in other places handle usage failures.
-  /// Throw a [UsageException] for a usage error of this command with
-  /// [message].
-  void usageError(String message) {
-    throw new UsageException(message, _getUsage());
-  }
-
   /// Parses a user-supplied integer [intString] named [name].
   ///
   /// If the parsing fails, prints a usage message and exits.
   int parseInt(String intString, String name) {
     try {
       return int.parse(intString);
     } on FormatException catch (_) {
       usageError('Could not parse $name "$intString".');
     }
   }
@@ skipping 85 matching lines @@
 
 /// Registers a [command] with [name] on [parser].
 void _registerCommand(String name, PubCommand command, ArgParser parser) {
   parser.addCommand(name, command.commandParser);
 
   // Recursively wire up any subcommands.
   command.subcommands.forEach((name, subcommand) {
     _registerCommand(name, subcommand, command.commandParser);
   });
 }