authdir_mode_any_nonhidserv() is an obsolete concept
/** Return true if we believe ourselves to be any kind of
* authoritative directory beyond just a hidserv authority. */
int
authdir_mode_any_nonhidserv(const or_options_t *options)
This phrase "hidserv authority" is from back in the days of v1 directory authorities, where there were 3 central authorities that collected and served all the hidden service descriptors.
Those days are gone, so references to a hidserv authority no longer make sense.
In particular, I think there are now only two types of directory authorities -- bridge authorities and main authorities. So this function could be replaced with just authdir_mode(). I'm marking it as 'easy' since it's a good one for a newbie to grab.