Driver fix to decouple from analyzer front-end deps.

pkg/analysis_server/lib/src/server/driver.dart

Index: pkg/analysis_server/lib/src/server/driver.dart
===================================================================
--- pkg/analysis_server/lib/src/server/driver.dart	(revision 45355)
+++ pkg/analysis_server/lib/src/server/driver.dart	(working copy)
@@ -17,7 +17,6 @@
 import 'package:analyzer/file_system/physical_file_system.dart';
 import 'package:analyzer/instrumentation/file_instrumentation.dart';
 import 'package:analyzer/instrumentation/instrumentation.dart';
-import 'package:analyzer/options.dart';
 import 'package:analyzer/plugin/plugin.dart';
 import 'package:analyzer/src/generated/engine.dart';
 import 'package:analyzer/src/generated/incremental_logger.dart';
@@ -419,3 +418,127 @@
     return uuid;
   }
 }
+
+/// Commandline argument parser. (Copied from analyzer/lib/options.dart)
+/// TODO(pquitslund): replaces with a simple [ArgParser] instance
+/// when the args package supports ignoring unrecognized
+/// options/flags (https://github.com/dart-lang/args/issues/9).
+class CommandLineParser {
+  final List<String> _knownFlags;
+  final bool _alwaysIgnoreUnrecognized;
+  final ArgParser _parser;
+
+  /// Creates a new command line parser
+  CommandLineParser({bool alwaysIgnoreUnrecognized: false})
+      : _knownFlags = <String>[],
+        _alwaysIgnoreUnrecognized = alwaysIgnoreUnrecognized,
+        _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,
+        abbr: abbr,
+        help: help,
+        defaultsTo: defaultsTo,
+        negatable: negatable,
+        callback: callback,
+        hide: hide);
+  }
+
+  /// Defines a value-taking option.
+  /// See [ArgParser.addOption()].
+  void addOption(String name, {String abbr, String help, List<String> allowed,
+      Map<String, String> allowedHelp, String defaultsTo, void callback(value),
+      bool allowMultiple: false}) {
+    _knownFlags.add(name);
+    _parser.addOption(name,
+        abbr: abbr,
+        help: help,
+        allowed: allowed,
+        allowedHelp: allowedHelp,
+        defaultsTo: defaultsTo,
+        callback: callback,
+        allowMultiple: allowMultiple);
+  }
+
+  /// Generates a string displaying usage information for the defined options.
+  /// See [ArgParser.usage].
+  String getUsage() => _parser.usage;
+
+  /// Parses [args], a list of command-line arguments, matches them against the
+  /// flags and options defined by this parser, and returns the result. The
+  /// values of any defined variables are captured in the given map.
+  /// See [ArgParser].
+  ArgResults parse(
+      List<String> args, Map<String, String> definedVariables) => _parser
+      .parse(_filterUnknowns(parseDefinedVariables(args, definedVariables)));
+
+  List<String> parseDefinedVariables(
+      List<String> args, Map<String, String> definedVariables) {
+    int count = args.length;
+    List<String> remainingArgs = <String>[];
+    for (int i = 0; i < count; i++) {
+      String arg = args[i];
+      if (arg == '--') {
+        while (i < count) {
+          remainingArgs.add(args[i++]);
+        }
+      } else if (arg.startsWith("-D")) {
+        definedVariables[arg.substring(2)] = args[++i];
+      } else {
+        remainingArgs.add(arg);
+      }
+    }
+    return remainingArgs;
+  }
+
+  List<String> _filterUnknowns(List<String> args) {
+
+    // Only filter args if the ignore flag is specified, or if
+    // _alwaysIgnoreUnrecognized was set to true
+    if (_alwaysIgnoreUnrecognized ||
+        args.contains('--ignore-unrecognized-flags')) {
+      
+      // Filter all unrecognized flags and options.
+      List<String> filtered = <String>[];
+      for (int i = 0; i < args.length; ++i) {
+        String arg = args[i];
+        if (arg.startsWith('--') && arg.length > 2) {
+          String option = arg.substring(2);
+          // strip the last '=value'
+          int equalsOffset = option.lastIndexOf('=');
+          if (equalsOffset != -1) {
+            option = option.substring(0, equalsOffset);
+          }
+          // check the option
+          if (!_knownFlags.contains(option)) {
+            //"eat" params by advancing to the next flag/option
+            i = _getNextFlagIndex(args, i);
+          } else {
+            filtered.add(arg);
+          }
+        } else {
+          filtered.add(arg);
+        }
+      }
+
+      return filtered;
+    } else {
+      return args;
+    }
+  }
+
+  _getNextFlagIndex(args, i) {
+    for (; i < args.length; ++i) {
+      if (args[i].startsWith('--')) {
+        return i;
+      }
+    }
+    return i;
+  }
+}