@Test
  public void testNewWatcher() throws IOException {
    assertThat(watcher.isOpen()).isTrue();
    assertThat(watcher.poll()).isNull();
    assertThat(watcher.queuedKeys()).isEmpty();
    watcher.close();
    assertThat(watcher.isOpen()).isFalse();
  }
Tests for {@link AbstractWatchService}.

@author Colin Decker
jimfs/src/test/java/com/google/common/jimfs/AbstractWatchServiceTest.java