Something I've had in mind for a long time and finally gotten around
to implementing: when you fill in the last pit or hole of a sokoban level,
it's considered to be completed so luck penalties for unsokobanish things
(breaking a boulder, dropping everything and squeezing onto a boulder's
spot, reading a scroll of earth) stop being assessed and most Sokoban-
specific movement restrictions (against pushing boulders diagonally,
squeezing diagonally between boulders, floating over a pit or hole without
falling in, digging of new holes by monsters) are lifted. Teleporting,
level teleporting, and phasing through walls are still prohibited when in
the sokoban branch of the dungeon. (Keeping the non-phasing one in place
prevents taking a shortcut to the final prize in order to bypass the
treasure zoo monsters.)
This adds level.flags.sokoban_rules, defines Sokoban macro to access
it, and replaces most In_sokoban(&u.uz) tests to check it instead. It
gets set when a sokoban level is pre-mapped at the end of level creation,
and if it is set then whenever a trap is deleted, the flag gets cleared
if there are no more pits or holes present on the level.
d592b9c4ae