Make the compact VM config keep open a receive port.

pkg/unittest/lib/compact_vm_config.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.
 
 /**
  * A test configuration that generates a compact 1-line progress bar. The bar is
  * updated in-place before and after each test is executed. If all test pass,
  * you should only see a couple lines in the terminal. If a test fails, the
  * failure is shown and the progress bar continues to be updated below it.
  */
 library compact_vm_config;
 
 import 'dart:async';
 import 'dart:io';
+import 'dart:isolate';
 
 import 'unittest.dart';
 import 'vm_config.dart';
 
 const String _GREEN = '\u001b[32m';
 const String _RED = '\u001b[31m';
 const String _NONE = '\u001b[0m';
 
 const int MAX_LINE = 80;
 
 class CompactVMConfiguration extends VMConfiguration {
+  // The VM won't shut down if a receive port is open. Use this to make sure
+  // we correctly wait for asynchronous tests.
+  ReceivePort _receivePort;
+
   DateTime _start;
   int _pass = 0;
   int _fail = 0;
 
   void onInit() {
+    _receivePort = new ReceivePort();
     // Override and don't call the superclass onInit() to avoid printing the
     // "unittest-suite-..." boilerplate.
   }
 
   void onStart() {
     _start = new DateTime.now();
   }
 
   void onTestStart(TestCase test) {
     super.onTestStart(test);
@@ skipping 16 matching lines @@
       if (test.stackTrace != null && test.stackTrace != '') {
         print(_indent(test.stackTrace));
       }
     }
   }
 
   void onDone(bool success) {
     // Override and don't call the superclass onDone() to avoid printing the
     // "unittest-suite-..." boilerplate.
     Future.wait([stdout.close(), stderr.close()]).then((_) {
+      _receivePort.close();
       exit(success ? 0 : 1);
     });
   }
 
   String _indent(String str) {
     return str.split("\n").map((line) => "  $line").join("\n");
   }
 
   void onSummary(int passed, int failed, int errors, List<TestCase> results,
       String uncaughtError) {
@@ skipping 110 matching lines @@
   // If the test is running on the Dart buildbots, we don't want to use this
   // config since it's output may not be what the bots expect.
   if (Platform.environment.containsKey('BUILDBOT_BUILDERNAME')) {
     return;
   }
 
   unittestConfiguration = _singleton;
 }
 
 final _singleton = new CompactVMConfiguration();