Add assertions to guard against programmer errors.
Add assertions to guard against programmer errors.

Plexxi/st2,StackStorm/st2,nzlosh/st2,Plexxi/st2,Plexxi/st2,StackStorm/st2,nzlosh/st2,StackStorm/st2,nzlosh/st2,Plexxi/st2,StackStorm/st2,nzlosh/st2