Rspec result corrupted occasionally

Like below

```
Run options: include {:focus=>true}

All examples were filtered out; ignoring {:focus=>true}

Randomized with seed 43456
.........Running via Spring preloader in process 55895
...

Finished in 0.58347 seconds (files took 0.53397 seconds to load)
12 examples, 0 failures

Randomized with seed 43456

```

I assume spring preloader makes it.
