golang: Transact can return nil?

We ran in a pretty weird issue where we use golang and `client.database.Transact` which could result in a nil as return value (https://github.com/FoundationDB/fdb-kubernetes-operator/pull/478). In the actual method we always return a boolean value (https://github.com/FoundationDB/fdb-kubernetes-operator/blob/master/controllers/lock_client.go#L84-L140) I couldn't find any notice about this behaviour in the docs https://pkg.go.dev/github.com/apple/foundationdb/bindings/go/src/fdb. So I just wanted to ask if we hit a strange error or if this iss just a behaviour that should be documented?

I mean the simple example suggest that there is no need to check for nil: https://pkg.go.dev/github.com/apple/foundationdb/bindings/go/src/fdb#hdr-Basic_Usage