Add verbosity levels for warnings and errors.

lib/src/command_runner.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.command_runner;
 
 import 'dart:async';
 import 'dart:io';
 
 import 'package:args/args.dart';
@@ skipping 27 matching lines @@
       "documentation.";
 
   PubCommandRunner()
       : super("pub", "Pub is a package manager for Dart.") {
     argParser.addFlag('version', negatable: false,
         help: 'Print pub version.');
     argParser.addFlag('trace',
          help: 'Print debugging information when an error occurs.');
     argParser.addOption('verbosity',
         help: 'Control output verbosity.',
-        allowed: ['normal', 'io', 'solver', 'all'],
+        allowed: ['error', 'warning', 'normal', 'io', 'solver', 'all'],
         allowedHelp: {
-          'normal': 'Show errors, warnings, and user messages.',
-          'io':     'Also show IO operations.',
-          'solver': 'Show steps during version resolution.',
-          'all':    'Show all output including internal tracing messages.'
+          'error':   'Show only errors.',
+          'warning': 'Show only errors and warnings.',
+          'normal':  'Show errors, warnings, and user messages.',
+          'io':      'Also show IO operations.',
+          'solver':  'Show steps during version resolution.',
+          'all':     'Show all output including internal tracing messages.'
         });
     argParser.addFlag('verbose', abbr: 'v', negatable: false,
         help: 'Shortcut for "--verbosity=all".');
     argParser.addFlag('with-prejudice', hide: !isAprilFools,
         negatable: false, help: 'Execute commands with prejudice.');
     argParser.addFlag('package-symlinks',
         negatable: true, defaultsTo: true,
         help: "Generate packages/ directories when installing packages.");
 
     addCommand(new BuildCommand());
@@ skipping 28 matching lines @@
     if (options['version']) {
       log.message('Pub ${sdk.version}');
       return;
     }
 
     if (options['trace']) {
       log.recordTranscript();
     }
 
     switch (options['verbosity']) {
-      case 'normal': log.verbosity = log.Verbosity.NORMAL; break;
-      case 'io':     log.verbosity = log.Verbosity.IO; break;
-      case 'solver': log.verbosity = log.Verbosity.SOLVER; break;
-      case 'all':    log.verbosity = log.Verbosity.ALL; break;
+      case 'error':   log.verbosity = log.Verbosity.ERROR; break;
+      case 'warning': log.verbosity = log.Verbosity.WARNING; break;
+      case 'normal':  log.verbosity = log.Verbosity.NORMAL; break;
+      case 'io':      log.verbosity = log.Verbosity.IO; break;
+      case 'solver':  log.verbosity = log.Verbosity.SOLVER; break;
+      case 'all':     log.verbosity = log.Verbosity.ALL; break;
       default:
         // No specific verbosity given, so check for the shortcut.
         if (options['verbose']) log.verbosity = log.Verbosity.ALL;
         break;
     }
 
     log.fine('Pub ${sdk.version}');
 
     await _validatePlatform();
 
@@ skipping 59 matching lines @@
   Future _validatePlatform() async {
     if (Platform.operatingSystem != 'windows') return;
 
     var result = await runProcess('ver', []);
     if (result.stdout.join('\n').contains('XP')) {
       log.error('Sorry, but pub is not supported on Windows XP.');
       await flushThenExit(exit_codes.USAGE);
     }
   }
 }