Wrap Directory.watch on linux for the watcher package.

pkg/watcher/test/directory_watcher/linux_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.
+
+import 'package:scheduled_test/scheduled_test.dart';
+import 'package:watcher/src/directory_watcher/linux.dart';
+import 'package:watcher/watcher.dart';
+
+import 'shared.dart';
+import '../utils.dart';
+
+main() {
+  initConfig();
+
+  watcherFactory = (dir) => new LinuxDirectoryWatcher(dir);
+
+  setUp(() {
+    // Increase the timeout because closing a [Directory.watch] stream blocks
+    // the main isolate for a very long time on Goobuntu, as of kernel
+    // 3.2.5-gg1336 (see issue 14606).
+    currentSchedule.timeout *= 3;
+
+    createSandbox();
+  });
+
+  sharedTests();
+
+  test('DirectoryWatcher creates a LinuxDirectoryWatcher on Linux', () {

[Bob Nystrom, 2013/11/06 19:24:04]

I don't think this should be part of the public API. From the user's
perspective, they should only know they got a DirectoryWatcher.

[nweiz, 2013/11/07 00:46:37]

It's not part of the public API -- we only get LinuxDirectoryWatcher in scope
because we're importing watcher/src/directory_watcher/linux. It's important that
we properly detect the OS, though, so I think this test is worthwhile.

+    expect(new DirectoryWatcher('.'),
+        new isInstanceOf<LinuxDirectoryWatcher>());
+  });
+
+  test('notifies even if the file contents are unchanged', () {
+    writeFile("a.txt", contents: "same");
+    writeFile("b.txt", contents: "before");
+    startWatcher();
+    writeFile("a.txt", contents: "same");
+    writeFile("b.txt", contents: "after");
+    expectModifyEvent("a.txt");
+    expectModifyEvent("b.txt");
+  });
+
+  test('emits events for many nested files moved out then immediately back in',
+      () {
+    withPermutations((i, j, k) =>
+        writeFile("dir/sub/sub-$i/sub-$j/file-$k.txt"));
+    startWatcher(dir: "dir");
+
+    renameDir("dir/sub", "sub");
+    renameDir("sub", "dir/sub");
+
+    inAnyOrder(() {
+      withPermutations((i, j, k) =>
+          expectRemoveEvent("dir/sub/sub-$i/sub-$j/file-$k.txt"));
+    });
+
+    inAnyOrder(() {
+      withPermutations((i, j, k) =>
+          expectAddEvent("dir/sub/sub-$i/sub-$j/file-$k.txt"));
+    });
+  });
+}