Some updates

code/__HELPERS/path.dm

@@ -5,7 +5,8 @@
  */
 
 /**
- * This is the proc you use whenever you want to have pathfinding more complex than "try stepping towards the thing"
+ * This is the proc you use whenever you want to have pathfinding more complex than "try stepping towards the thing".
+ * If no path was found, returns an empty list, which is important for bots like medibots who expect an empty list rather than nothing.
  *
  * Arguments:
  * * caller: The movable atom that's trying to find the path
@@ -15,8 +16,9 @@
  * * id: An ID card representing what access we have and what doors we can open. Its location relative to the pathing atom is irrelevant
  * * simulated_only: Whether we consider turfs without atmos simulation (AKA do we want to ignore space)
  * * exclude: If we want to avoid a specific turf, like if we're a mulebot who already got blocked by some turf
+ * * skip_first: Whether or not to delete the first item in the path. This would be done because the first item is the starting tile, which can break movement for some creatures.
  */
-/proc/get_path_to(caller, end, max_distance = 30, mintargetdist, id=null, simulated_only = TRUE, turf/exclude)
+/proc/get_path_to(caller, end, max_distance = 30, mintargetdist, id=null, simulated_only = TRUE, turf/exclude, skip_first=TRUE)
 	if(!caller || !get_turf(end))
 		return
 
@@ -33,12 +35,14 @@
 	SSpathfinder.mobs.found(l)
 	if(!path)
 		path = list()
+	if(length(path) > 0 && skip_first)
+		path.Cut(1,2)
 	return path
 
 /**
  * A helper macro to see if it's possible to step from the first turf into the second one, minding things like door access and directional windows.
- * Note that this can only be used inside the [datum/pathfind][pathfind datum] since it uses variables from said datum
- * If you really want to optimize things, optimize this, cuz this gets called a lot
+ * Note that this can only be used inside the [datum/pathfind][pathfind datum] since it uses variables from said datum.
+ * If you really want to optimize things, optimize this, cuz this gets called a lot.
  */
 #define CAN_STEP(cur_turf, next) (next && !next.density && cur_turf.Adjacent(next) && !(simulated_only && SSpathfinder.space_type_cache[next.type]) && !cur_turf.LinkBlockedWithAccess(next,caller, id) && (next != avoid))
 /// Another helper macro for JPS, for telling when a node has forced neighbors that need expanding
@@ -128,16 +132,21 @@
 	src.simulated_only = simulated_only
 	src.avoid = avoid
 
-/// The proc you use to run the search, returns FALSE if it's invalid, an empty list if no path could be found, or a valid path to the target
+/**
+ * search() is the proc you call to kick off and handle the actual pathfinding, and kills the pathfind datum instance when it's done.
+ *
+ * If a valid path was found, it's returned as a list. If invalid or cross-z-level params are entered, or if there's no valid path found, we
+ * return null, which [/proc/get_path_to] translates to an empty list (notable for simple bots, who need empty lists)
+ */
 /datum/pathfind/proc/search()
 	start = get_turf(caller)
 	if(!start || !end)
 		stack_trace("Invalid A* start or destination")
-		return FALSE
+		return
 	if(start.z != end.z || start == end ) //no pathfinding between z levels
-		return FALSE
+		return
 	if(max_distance && (max_distance < get_dist(start, end))) //if start turf is farther than max_distance from end turf, no need to do anything
-		return FALSE
+		return
 
 	//initialization
 	var/datum/jps_node/current_processed_node = new (start, -1, 0, end)
@@ -165,6 +174,7 @@
 	if(path)
 		for(var/i = 1 to round(0.5 * length(path)))
 			path.Swap(i, length(path) - i + 1)
+
 	sources = null
 	qdel(open)
 	return path

code/modules/antagonists/changeling/powers/tiny_prick.dm

@@ -47,8 +47,8 @@
 		return
 	if(!isturf(user.loc))
 		return
-	if(!get_path_to(user, target, max_distance = changeling.sting_range, simulated_only = FALSE))
-		return
+	if(!length(get_path_to(user, target, max_distance = changeling.sting_range, simulated_only = FALSE)))
+		return // no path within the sting's range is found. what a weird place to use the pathfinding system
 	return 1
 
 /obj/effect/proc_holder/changeling/sting/sting_feedback(mob/user, mob/target)