public static void SimpleTest() { IFileWatcher watcher = New <IFileWatcher>("c:\temp"); string fullName = String.Empty; watcher.FileChanged += (object sender, FileWatcherEventArgs e) => { fullName = e.FullNames.First(); }; FakeFileWatcher fakeWatcher = (FakeFileWatcher)watcher; fakeWatcher.OnChanged(new FileWatcherEventArgs("c:\temp\test.txt")); Assert.That(fullName, Is.EqualTo("c:\temp\test.txt"), "The changed event should pass the path specified."); }