add sanity checks, catch bug
add sanity checks, catch bug

mtlynch/Sia,mtlynch/Sia,mharkus/Sia,ChrisSchinnerl/Sia,mharkus/Sia,ChrisSchinnerl/Sia,ericflo/Sia,MrStrong/Sia,NebulousLabs/Sia,ericflo/Sia,MrStrong/Sia,NebulousLabs/Sia