add unit tests to singleton
add unit tests to singleton

dharmatech/factor,mecon/factor,slavapestov/factor,nicolas-p/factor,erg/factor,cataska/factor,dch/factor,dch/factor,sarvex/factor-lang,dharmatech/factor,sarvex/factor-lang,littledan/Factor,Keyholder/factor,slavapestov/factor,tgunr/factor,sarvex/factor-lang,jwmerrill/factor,sarvex/factor-lang,dch/factor,mrjbq7/factor,factor/factor,kingcons/factor,bjourne/factor,cataska/factor,mrjbq7/factor,erg/factor,tgunr/factor,factor/factor,erg/factor,ehird/factor,AlexIljin/factor,mcandre/factor,nicolas-p/factor,seckar/factor,bpollack/factor,mcandre/factor,cataska/factor,bjourne/factor,bjourne/factor,seckar/factor,slavapestov/factor,bjourne/factor,bpollack/factor,Keyholder/factor,nicolas-p/factor,erg/factor,jwmerrill/factor,dch/factor,AlexIljin/factor,mcandre/factor,sarvex/factor-lang,bjourne/factor,mecon/factor,sarvex/factor-lang,mecon/factor,mcandre/factor,ehird/factor,nicolas-p/factor,factor/factor,mrjbq7/factor,ehird/factor,mecon/factor,tgunr/factor,bpollack/factor,AlexIljin/factor,mrjbq7/factor,littledan/Factor,kingcons/factor,bjourne/factor,mcandre/factor,tgunr/factor,dharmatech/factor,mcandre/factor,kingcons/factor,nicolas-p/factor,factor/factor,Keyholder/factor,bpollack/factor,bpollack/factor,littledan/Factor,slavapestov/factor,nicolas-p/factor,mecon/factor,mrjbq7/factor,seckar/factor,littledan/Factor,erg/factor,AlexIljin/factor,erg/factor,mrjbq7/factor,kingcons/factor,sarvex/factor-lang,slavapestov/factor,dch/factor,erg/factor,bjourne/factor,ceninan/factor,jwmerrill/factor,AlexIljin/factor,slavapestov/factor,dch/factor,ceninan/factor,ceninan/factor,bpollack/factor,cataska/factor,slavapestov/factor,mcandre/factor,AlexIljin/factor,tgunr/factor,bpollack/factor,mecon/factor,ceninan/factor,mecon/factor,factor/factor,factor/factor,tgunr/factor,nicolas-p/factor,AlexIljin/factor