Hello, i wonder all of this, and i tried to reply to myself. Please correct me if wrong.
Is uscan run outside debian/ directory ? i suppose yes Inside debian/ directory, without upstream source ? no if optional command is not run, yes if it is Inside debian/ directory, with upstream source ? no, that would be crazy Is the optional command in debian/watch line run by the PTS tracker ? no, too dangerous security-wise, but i had to ask Jérémy.