Is a RWMutex reantrant? The documentation does not say anything about this...

~~Context: ~~
AddInFlight acquires a RW-Lock (mi.inFlight.Lock()) and then calls Has, which tries to acquire a Read-Lock (mi.idxMutex.RLock()). Without RWMutex being reantrant this should fail/dead-lock.

Assuming go locks to be reantrant I tried the same while implementing my draft of StoreInProgress. Due to that I learned the hard way, that my assumption was wrong and Mutex (not RWMutex) is not reantrant.

Edit: Reading my comment again, I noticed that two different lock objects are involved.

Edit: Nothing is locked twice. Everything is alright.