gistfile1.txt

I'm trying to switch from :dalli_store to :mem_cache_store.


With :mem_cache_store, I get this:

```
Rails.cache.fetch("zone#{zone.id}_latest_event") do
  Event.where(zone: zone).desc(:starts_at).for_recording_create.limit(1).first
end
=> nil
Event.where(zone: zone).desc(:starts_at).for_recording_create.limit(1).first
=> #<Event _id: 5fe0cf57cf2048d63bb3c9f1...
```

With :dalli_store, I get this:

```
Rails.cache.fetch("zone#{zone.id}_latest_event") do
  Event.where(zone: zone).desc(:starts_at).for_recording_create.limit(1).first
end
=> #<Event _id: 5fe0cf57cf2048d63bb3c9f1...
Event.where(zone: zone).desc(:starts_at).for_recording_create.limit(1).first
=> #<Event _id: 5fe0cf57cf2048d63bb3c9f1...
```

It seems that :mem_cache_store is caching nil as a value, while :dalli_store is not? - How can I stop :mem_cache_store from doing this?