format code, removed unused variables and deprecated usage

test/trailing_options_test.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 trailing_options_test;
 
 import 'package:unittest/unittest.dart';
 import 'package:args/args.dart';
 
 void main() {
   test('allowTrailingOptions defaults to false', () {
     var parser = new ArgParser();
     expect(parser.allowTrailingOptions, isFalse);
   });
 
   group('when trailing options are allowed', () {
     var parser;
     setUp(() {
       parser = new ArgParser(allowTrailingOptions: true);
     });
 
-    void expectThrows(List<String> args) =>
-      expect(() => parser.parse(args), throwsFormatException,
-          reason: "with allowTrailingOptions: true");
+    void expectThrows(List<String> args) => expect(
+        () => parser.parse(args), throwsFormatException,
+        reason: "with allowTrailingOptions: true");
 
     test('collects non-options in rest', () {
       parser.addFlag('flag');
       parser.addOption('opt', abbr: 'o');
       var results = parser.parse(['a', '--flag', 'b', '-o', 'value', 'c']);
       expect(results['flag'], isTrue);
       expect(results['opt'], equals('value'));
       expect(results.rest, equals(['a', 'b', 'c']));
     });
 
@@ skipping 42 matching lines @@
 
     test('throws on a command', () {
       parser.addCommand('com');
       expectThrows(['arg', 'com']);
     });
   });
 
   test("uses the innermost command's trailing options behavior", () {
     var parser = new ArgParser(allowTrailingOptions: true);
     parser.addFlag('flag', abbr: 'f');
-    var command = parser.addCommand('cmd',
-        new ArgParser(allowTrailingOptions: false));
+    var command =
+        parser.addCommand('cmd', new ArgParser(allowTrailingOptions: false));
     command.addFlag('verbose', abbr: 'v');
 
     var results = parser.parse(['a', '-f', 'b']);
     expect(results['flag'], isTrue);
     expect(results.rest, equals(['a', 'b']));
 
     results = parser.parse(['cmd', '-f', 'a', '-v', '--unknown']);
     expect(results['flag'], isTrue); // Not trailing.
     expect(results.command['verbose'], isFalse);
     expect(results.command.rest, equals(['a', '-v', '--unknown']));
   });
 }