fix #620, infer the input files from sources

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.
 import 'package:bazel_worker/src/async_message_grouper.dart';
 import 'package:bazel_worker/testing.dart';
 import 'package:test/test.dart';
 
-import 'package:dev_compiler/src/compiler/compiler.dart'
-    show missingPartErrorCode, unusedPartWarningCode;
-
 main() {
   group('Hello World', () {
     final argsFile = new File('test/worker/hello_world.args').absolute;
     final inputDartFile = new File('test/worker/hello_world.dart').absolute;
     final outputJsFile = new File('test/worker/hello_world.js').absolute;
     final executableArgs = ['bin/dartdevc.dart', 'compile',];
     final compilerArgs = [
       '--no-source-map',
       '--no-summarize',
       '-o',
@@ skipping 187 matching lines @@
         outJS.path,
         partFile.path,
         libraryFile.path,
       ]);
       expect(result.stdout, isEmpty);
       expect(result.stderr, isEmpty);
       expect(result.exitCode, 0);
       expect(outJS.existsSync(), isTrue);
     });
 
-    test('error if part is not supplied', () {
+    test('works if part is not supplied', () {
       var result = Process.runSync('dart', [
         'bin/dartdevc.dart',
         'compile',
         '--no-summarize',
         '--no-source-map',
         '-o',
         outJS.path,
         libraryFile.path,
       ]);
-      expect(
-          result.stdout,
-          startsWith('[error] ${missingPartErrorCode.message} '
-              '(test/worker/greeting.dart, line 1, col 1)'));
+      expect(result.stdout, isEmpty);
       expect(result.stderr, isEmpty);
-      expect(result.exitCode, 1);
-      expect(outJS.existsSync(), isFalse);
+      expect(result.exitCode, 0);
+      expect(outJS.existsSync(), isTrue);
     });
 
-    test('warning if part without library is supplied', () {
+    test('part without library is silently ignored', () {
       var result = Process.runSync('dart', [
         'bin/dartdevc.dart',
         'compile',
         '--no-summarize',
         '--no-source-map',
         '-o',
         outJS.path,
         partFile.path,
       ]);
-      expect(
-          result.stdout,
-          startsWith('[warning] ${unusedPartWarningCode.message} '
-              '(test/worker/greeting.dart, line 1, col 1)'));
+      expect(result.stdout, isEmpty);
       expect(result.stderr, isEmpty);
       expect(result.exitCode, 0);
       expect(outJS.existsSync(), isTrue);
     });
   });
 }
 
 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';
   }
 }