refactor DDC to support --ignore-unrecognized-flags

pkg/dev_compiler/test/worker/worker_test.dart

 // Copyright (c) 2016, 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:async';
 import 'dart:convert';
 import 'dart:io';
 
 import 'package:bazel_worker/bazel_worker.dart';
 // TODO(jakemac): Remove once this is a part of the testing library.
@@ skipping 66 matching lines @@
     test('can compile in basic mode', () {
       var args = executableArgs.toList()..addAll(compilerArgs);
       var result = Process.runSync('dart', args);
 
       expect(result.exitCode, EXIT_CODE_OK);
       expect(result.stdout, isEmpty);
       expect(result.stderr, isEmpty);
       expect(outputJsFile.existsSync(), isTrue);
     });
 
+    test('unknown options', () {
+      var args = new List<String>.from(executableArgs)
+        ..add('--does-not-exist')
+        ..addAll(compilerArgs);
+      var result = Process.runSync('dart', args);
+
+      expect(result.exitCode, 64);
+      expect(result.stdout,
+          contains('Could not find an option named "does-not-exist"'));
+      expect(result.stderr, isEmpty);
+      expect(outputJsFile.existsSync(), isFalse);
+    });
+
+    test('unknown options ignored', () {
+      var args = new List<String>.from(executableArgs)
+        ..add('--does-not-exist')
+        ..add('--ignore-unrecognized-flags')
+        ..addAll(compilerArgs);
+      var result = Process.runSync('dart', args);
+
+      expect(result.exitCode, EXIT_CODE_OK);
+      expect(result.stdout, isEmpty);
+      expect(result.stderr, isEmpty);
+      expect(outputJsFile.existsSync(), isTrue);
+    });
+
     test('can compile in basic mode with args in a file', () async {
       argsFile.createSync();
       argsFile.writeAsStringSync(compilerArgs.join('\n'));
       var args = executableArgs.toList()..add('@${argsFile.path}');
       var process = await Process.start('dart', args);
       stderr.addStream(process.stderr);
       var futureProcessOutput = process.stdout.map(UTF8.decode).toList();
 
       expect(await process.exitCode, EXIT_CODE_OK);
       expect((await futureProcessOutput).join(), isEmpty);
@@ skipping 65 matching lines @@
     final dartSdkSummary = new File('lib/sdk/ddc_sdk.sum').absolute;
     final badFileDart = new File('test/worker/bad.dart').absolute;
     final badFileJs = new File('test/worker/bad.js').absolute;
 
     tearDown(() {
       if (badFileDart.existsSync()) badFileDart.deleteSync();
       if (badFileJs.existsSync()) badFileJs.deleteSync();
     });
 
     test('incorrect usage', () {
-      var result = Process.runSync('dart', ['bin/dartdevc.dart', '--dart-sdk-summary', dartSdkSummary.path, 'oops',]);
+      var result = Process.runSync('dart', [
+        'bin/dartdevc.dart',
+        '--dart-sdk-summary',
+        dartSdkSummary.path,
+        'oops',
+      ]);
       expect(result.exitCode, 64);
       expect(
           result.stdout, contains('Please include the output file location.'));
       expect(result.stdout, isNot(contains('#0')));
     });
 
     test('compile errors', () {
       badFileDart.writeAsStringSync('main() => "hello world"');
       var result = Process.runSync('dart', [
         'bin/dartdevc.dart',
@@ skipping 87 matching lines @@
 Future<WorkResponse> _readResponse(MessageGrouper messageGrouper) async {
   var buffer = (await messageGrouper.next) as List<int>;
   try {
     return new WorkResponse.fromBuffer(buffer);
   } catch (_) {
     var bufferAsString =
         buffer == null ? '' : 'String: ${UTF8.decode(buffer)}\n';
     throw 'Failed to parse response:\nbytes: $buffer\n$bufferAsString';
   }
 }