Fix multiple crashes

api/behaviors.lua

@@ -745,8 +745,8 @@ creatura.register_utility("animalia:boid_wander", function(self, group)
                 group_tick = 0
             end
             if (move
-            and goal)
+            or far_from_group)
-            or far_from_group then
+            and goal then
                 animalia.action_boid_walk(self, goal, 6, "creatura:neighbors", 0.35)
             else
                 creatura.action_idle(self, idle_time)
@@ -979,7 +979,9 @@ creatura.register_utility("animalia:boid_flee_from_player", function(self, playe
             and vec_dist(pos, self.lasso_pos) > 10 then
                 escape_pos = self.lasso_pos
             end
-            animalia.action_boid_walk(self, escape_pos, 6, "creatura:obstacle_avoidance", 1, "run")
+            if escape_pos then
+                animalia.action_boid_walk(self, escape_pos, 6, "creatura:obstacle_avoidance", 1, "run")
+            end
         end
         if vec_dist(pos, tpos) > self.tracking_range + (#mobs_in_group or 0) then
             return true

api/spawning.lua

@@ -257,7 +257,8 @@ minetest.register_on_generated(function(minp, maxp)
                     z = zcen,
                 }
                 local spawnable_mobs = get_spawnable_mobs(center)
-                if spawnable_mobs then
+                if spawnable_mobs
+                and #spawnable_mobs > 0 then
                     local mob = spawnable_mobs[random(#spawnable_mobs)]
                     table.insert(animalia.spawn_queue, {pos = center, mob = mob, group = random(3, 4)})
                     table.insert(animalia.spawn_points, center)
@@ -280,7 +281,8 @@ minetest.register_globalstep(function(dtime)
                 if dist_to_nearest_player(point) < 48
                 and minetest.get_node_or_nil(point) then
                     local spawnable_mobs = get_spawnable_mobs(point)
-                    if spawnable_mobs then
+                    if spawnable_mobs
+                    and #spawnable_mobs > 0 then
                         local mob = spawnable_mobs[random(#spawnable_mobs)]
                         local objects = minetest.get_objects_inside_radius(point, 32)
                         local spawn = true

mobs/wolf.lua

@@ -101,6 +101,7 @@ creatura.register_mob("animalia:wolf", {
 				end
 				if target then
 					if is_attacking
+					and self._utility_data.args[2]
 					and self._utility_data.args[2] == target then
 						return 0
 					end