Split up tests and add some heartbeats to try to make them not timeout.

pkg/watcher/test/utils.dart

 // Copyright (c) 2012, 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 watcher.test.utils;
 
 import 'dart:async';
 import 'dart:io';
 
 import 'package:path/path.dart' as p;
@@ skipping 59 matching lines @@
     mockGetModificationTime(null);
   }, "delete sandbox");
 }
 
 /// Creates a new [DirectoryWatcher] that watches a temporary directory.
 ///
 /// Normally, this will pause the schedule until the watcher is done scanning
 /// and is polling for changes. If you pass `false` for [waitForReady], it will
 /// not schedule this delay.
 DirectoryWatcher createWatcher({bool waitForReady}) {
-  _watcher = new DirectoryWatcher(_sandboxDir);
+  // Use a short delay to make the tests run quickly.
+  _watcher = new DirectoryWatcher(_sandboxDir,
+      pollingDelay: new Duration(milliseconds: 100));

[nweiz, 2013/07/12 22:37:17]

This could probably be 0s or something vanishingly small without any adverse
effects.

 
   // Wait until the scan is finished so that we don't miss changes to files
   // that could occur before the scan completes.
   if (waitForReady != false) {
     schedule(() => _watcher.ready);
   }
 
   currentSchedule.onComplete.schedule(() {
     _nextEvent = 0;
     _watcher = null;
@@ skipping 86 matching lines @@
 
   _ChangeMatcher(this.type, this.path);
 
   Description describe(Description description) {
     description.add("$type $path");
   }
 
   bool matches(item, Map matchState) =>
       item is WatchEvent && item.type == type && item.path == path;
 }