   testutil.FatalStack(t, "failed to watch the event")  }   s.Put([]byte("foo0"), []byte("bar0"), 0)  select {  case resp := <-w.Chan():   if resp.WatchID != wid {    t.Errorf("resp.WatchID got = %d, want = %d", resp.WatchID, wid)   }   ev := resp.Events[0]   if !reflect.DeepEqual(ev, wev[0]) {    t.Errorf("watched event = %+v, want %+v", ev, wev[0])   }  case <-time.After(0 * time.Second):   testutil.FatalStack(t, "failed to watch the event")  }   