@Test(expected = FilesystemTrackerStartupException.class)
public void Should_throw_When_taskFactoryThrows()
        throws Exception {

    FilesystemTracker tracker = new FilesystemTracker(pathFilterMock, taskFactoryMock, fileSystemMock);
    when(taskFactoryMock.createRunnable(any(), any())).thenThrow(new IOException());
    tracker.start(directoryMock);
}