Wrap Directory.watch on linux for the watcher package.

pkg/watcher/test/directory_watcher_test.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.
-
-import 'package:scheduled_test/scheduled_test.dart';
-
-import 'utils.dart';
-
-main() {
-  initConfig();
-
-  setUp(createSandbox);
-
-  test('does not notify for files that already exist when started', () {
-    // Make some pre-existing files.
-    writeFile("a.txt");
-    writeFile("b.txt");
-
-    createWatcher();
-
-    // Change one after the watcher is running.
-    writeFile("b.txt", contents: "modified");
-
-    // We should get a modify event for the changed file, but no add events
-    // for them before this.
-    expectModifyEvent("b.txt");
-  });
-
-  test('notifies when a file is added', () {
-    createWatcher();
-    writeFile("file.txt");
-    expectAddEvent("file.txt");
-  });
-
-  test('notifies when a file is modified', () {
-    writeFile("file.txt");
-    createWatcher();
-    writeFile("file.txt", contents: "modified");
-    expectModifyEvent("file.txt");
-  });
-
-  test('notifies when a file is removed', () {
-    writeFile("file.txt");
-    createWatcher();
-    deleteFile("file.txt");
-    expectRemoveEvent("file.txt");
-  });
-
-  test('notifies when a file is moved', () {
-    writeFile("old.txt");
-    createWatcher();
-    renameFile("old.txt", "new.txt");
-    expectAddEvent("new.txt");
-    expectRemoveEvent("old.txt");
-  });
-
-  test('notifies when a file is modified multiple times', () {
-    writeFile("file.txt");
-    createWatcher();
-    writeFile("file.txt", contents: "modified");
-    expectModifyEvent("file.txt");
-    writeFile("file.txt", contents: "modified again");
-    expectModifyEvent("file.txt");
-  });
-
-  test('does not notify if the file contents are unchanged', () {
-    writeFile("a.txt", contents: "same");
-    writeFile("b.txt", contents: "before");
-    createWatcher();
-    writeFile("a.txt", contents: "same");
-    writeFile("b.txt", contents: "after");
-    expectModifyEvent("b.txt");
-  });
-
-  test('does not notify if the modification time did not change', () {
-    writeFile("a.txt", contents: "before");
-    writeFile("b.txt", contents: "before");
-    createWatcher();
-    writeFile("a.txt", contents: "after", updateModified: false);
-    writeFile("b.txt", contents: "after");
-    expectModifyEvent("b.txt");
-  });
-
-  test('watches files in subdirectories', () {
-    createWatcher();
-    writeFile("a/b/c/d/file.txt");
-    expectAddEvent("a/b/c/d/file.txt");
-  });
-
-  test('watches a directory created after the watcher', () {
-    // Watch a subdirectory that doesn't exist yet.
-    createWatcher(dir: "a");
-
-    // This implicity creates it.
-    writeFile("a/b/c/d/file.txt");
-    expectAddEvent("a/b/c/d/file.txt");
-  });
-
-  test('when the watched directory is deleted, removes all files', () {
-    writeFile("dir/a.txt");
-    writeFile("dir/b.txt");
-
-    createWatcher(dir: "dir");
-
-    deleteDir("dir");
-    expectRemoveEvents(["dir/a.txt", "dir/b.txt"]);
-  });
-}