Add ignore-unrecognized-flags as an option to the command line options of analysis server

pkg/analyzer/lib/options.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 options;
 
 import 'dart:io';
 
 import 'package:args/args.dart';
 
@@ skipping 115 matching lines @@
       File versionFile = new File(versionPath);
       return versionFile.readAsStringSync().trim();
     } catch (_) {
       // This happens when the script is not running in the context of an SDK.
       return "<unknown>";
     }
   }
 
   static CommandLineOptions _parse(List<String> args) {
     args = args.expand((String arg) => arg.split('=')).toList();
-    var parser = new _CommandLineParser()
+    var parser = new CommandLineParser()
         ..addFlag(
             'batch',
             abbr: 'b',
             help: 'Run in batch mode',
             defaultsTo: false,
             negatable: false)
         ..addOption('dart-sdk', help: 'The path to the Dart SDK')
         ..addOption(
             'package-root',
             abbr: 'p',
@@ skipping 54 matching lines @@
             negatable: false)
         ..addFlag(
             'help',
             abbr: 'h',
             help: 'Display this help message',
             defaultsTo: false,
             negatable: false)
         ..addOption(
             'url-mapping',
             help: '--url-mapping=libraryUri,/path/to/library.dart directs the '
-                  'analyzer to use "library.dart" as the source for an import '
-                  'of "libraryUri"',
+                'analyzer to use "library.dart" as the source for an import ' 'of "libraryUri"',
             allowMultiple: true)
         //
         // Hidden flags.
         //
         ..addFlag(
             'enable-async',
             help: 'Enable support for the proposed async feature',
             defaultsTo: false,
             negatable: false,
             hide: true)
@@ skipping 52 matching lines @@
       Map<String, String> customUrlMappings = <String, String>{};
       for (String mapping in results['url-mapping']) {
         List<String> splitMapping = mapping.split(',');
         if (splitMapping.length != 2) {
           _showUsage(parser);
           exit(15);
         }
         customUrlMappings[splitMapping[0]] = splitMapping[1];
       }
       return new CommandLineOptions._fromArgs(
-          results, definedVariables, customUrlMappings);
+          results,
+          definedVariables,
+          customUrlMappings);
     } on FormatException catch (e) {
       print(e.message);
       _showUsage(parser);
       exit(15);
     }
 
   }
 
   static _showUsage(parser) {
     print('Usage: $_BINARY_NAME [options...] <libraries to analyze...>');
     print(parser.getUsage());
     print('');
     print('For more information, see http://www.dartlang.org/tools/analyzer.');
   }
 }
 
 /**
  * Commandline argument parser.
  *
  * TODO(pquitslund): when the args package supports ignoring unrecognized
  * options/flags, this class can be replaced with a simple [ArgParser] instance.
  */
-class _CommandLineParser {
+class CommandLineParser {
 
   final List<String> _knownFlags;
   final ArgParser _parser;
 
   /** Creates a new command line parser */
-  _CommandLineParser()
+  CommandLineParser()
       : _knownFlags = <String>[],
         _parser = new ArgParser(allowTrailingOptions: true);
 
 
+  ArgParser get parser => _parser;
+
   /**
    * Defines a flag.
    *
    * See [ArgParser.addFlag()].
    */
   void addFlag(String name, {String abbr, String help, bool defaultsTo: false,
       bool negatable: true, void callback(bool value), bool hide: false}) {
     _knownFlags.add(name);
     _parser.addFlag(
         name,
@@ skipping 95 matching lines @@
 
   _getNextFlagIndex(args, i) {
     for ( ; i < args.length; ++i) {
       if (args[i].startsWith('--')) {
         return i;
       }
     }
     return i;
   }
 }