Merge pull request 'Mob Step error handling' (#3452) from mobs_error_handling into master

Reviewed-on: MineClone2/MineClone2#3452

mods/ENTITIES/mcl_mobs/api.lua

@@ -4,6 +4,7 @@ local math, vector, minetest, mcl_mobs = math, vector, minetest, mcl_mobs
 -- API for Mobs Redo: MineClone 2 Edition (MRM)
 
 local PATHFINDING = "gowp"
+local CRASH_WARN_FREQUENCY = 60
 
 -- Localize
 local S = minetest.get_translator("mcl_mobs")
@@ -357,8 +358,7 @@ function mob_class:outside_limits()
 	end
 end
 
--- main mob function
+local function on_step_work (self, dtime)
-function mob_class:on_step(dtime)
 	local pos = self.object:get_pos()
 	if not pos then return end
 
@@ -446,6 +446,36 @@ function mob_class:on_step(dtime)
 	end
 end
 
+local last_crash_warn_time = 0
+
+local on_step_error_handler = function ()
+	local info = debug.getinfo(1, "SnlufL")
+
+	local current_time = os.time()
+	local time_since_warning = current_time - last_crash_warn_time
+
+	--minetest.log("previous_crash_time: " .. current_time)
+	--minetest.log("last_crash_time: " .. last_crash_warn_time)
+	--minetest.log("time_since_warning: " .. time_since_warning)
+
+	if time_since_warning > CRASH_WARN_FREQUENCY then
+		last_crash_warn_time = current_time
+		minetest.log("A game crashing bug was prevented. Please provide debug.log information to MineClone2 dev team for investigation. (Search for: --- Bug report start)")
+	end
+	minetest.log("action", "--- Bug report start (please provide a few lines before this also for context) ---")
+	minetest.log("action", "Stack trace: ".. tostring(debug.traceback()))
+	minetest.log("action", "Bug info: ".. dump(info))
+	minetest.log("action", "--- Bug report end ---")
+end
+
+-- main mob function
+function mob_class:on_step(dtime)
+	local status, retVal = xpcall(on_step_work, on_step_error_handler, self, dtime)
+	if status then
+		return retVal
+	end
+end
+
 local timer = 0
 minetest.register_globalstep(function(dtime)
 	timer = timer + dtime