Add named groups for command-line options.

lib/src/runner/configuration.dart

 // Copyright (c) 2015, 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.
 
 import 'dart:io';
 import 'dart:math' as math;
 
 import 'package:args/args.dart';
 import 'package:path/path.dart' as p;
 
@@ skipping 17 matching lines @@
 
     var allPlatforms = TestPlatform.all.toList();
     if (!Platform.isMacOS) allPlatforms.remove(TestPlatform.safari);
     if (!Platform.isWindows) allPlatforms.remove(TestPlatform.internetExplorer);
 
     parser.addFlag("help", abbr: "h", negatable: false,
         help: "Shows this usage information.");
     parser.addFlag("version", negatable: false,
         help: "Shows the package's version.");
     parser.addOption("package-root", hide: true);
+
+    parser.addSeparator("======== Selecting Tests");
     parser.addOption("name",
         abbr: 'n',
         help: 'A substring of the name of the test to run.\n'
             'Regular expression syntax is supported.');
     parser.addOption("plain-name",
         abbr: 'N',
         help: 'A plain-text substring of the name of the test to run.');
     // TODO(nweiz): Support the full platform-selector syntax for choosing which
     // tags to run. In the shorter term, disallow non-"identifier" tags.
     parser.addOption("tags",
         abbr: 't',
         help: 'Run only tests with all of the specified tags.',
         allowMultiple: true);
     parser.addOption("tag", hide: true, allowMultiple: true);
     parser.addOption("exclude-tags",
         abbr: 'x',
         help: "Don't run tests with any of the specified tags.",
         allowMultiple: true);
     parser.addOption("exclude-tag", hide: true, allowMultiple: true);
+
+    parser.addSeparator("======== Running Tests");
     parser.addOption("platform",
         abbr: 'p',
         help: 'The platform(s) on which to run the tests.',
         allowed: allPlatforms.map((platform) => platform.identifier).toList(),
         defaultsTo: 'vm',
         allowMultiple: true);
     parser.addOption("concurrency",
         abbr: 'j',
         help: 'The number of concurrent test suites run.\n'
             '(defaults to $_defaultConcurrency)',
         valueHelp: 'threads');
     parser.addOption("pub-serve",
         help: 'The port of a pub serve instance serving "test/".',
         valueHelp: 'port');
     parser.addFlag("pause-after-load",
         help: 'Pauses for debugging before any tests execute.\n'
             'Implies --concurrency=1.\n'
             'Currently only supported for browser tests.',
         negatable: false);
+
+    parser.addSeparator("======== Output");
     parser.addOption("reporter",
         abbr: 'r',
         help: 'The runner used to print test results.',
         allowed: ['compact', 'expanded', 'json'],
         defaultsTo: Platform.isWindows ? 'expanded' : 'compact',
         allowedHelp: {
       'compact': 'A single line, updated continuously.',
       'expanded': 'A separate line for each update.',
       'json': 'A machine-readable format (see https://goo.gl/0HRhdZ).'
     });
@@ skipping 155 matching lines @@
             : Uri.parse("http://localhost:$pubServePort"),
         concurrency = pauseAfterLoad
             ? 1
             : (concurrency == null ? _defaultConcurrency : concurrency),
         platforms = platforms == null ? [TestPlatform.vm] : platforms.toList(),
         paths = paths == null ? ["test"] : paths.toList(),
         explicitPaths = paths != null,
         this.tags = tags,
         this.excludeTags = excludeTags;
 }