Fix mob egg double-spawns (#4657)

If you spawn a mob clicking on a wall, two mobs will be spawned.

To reproduce: face a stack of stones, with a spawn egg click on the side of a stone. It does not happen when you click the top of a node, because spawning below fails and only the second one succeeds.

Reviewed-on: VoxeLibre/VoxeLibre#4657
Reviewed-by: the-real-herowl <the-real-herowl@noreply.git.minetest.land>
Co-authored-by: kno10 <kno10@noreply.git.minetest.land>
Co-committed-by: kno10 <kno10@noreply.git.minetest.land>

mods/ENTITIES/mcl_mobs/api.lua

@@ -388,7 +388,7 @@ end
 
 
 
-local function on_step_work (self, dtime)
+local function on_step_work(self, dtime, moveresult)
 	local pos = self.object:get_pos()
 	if not pos then return end
 
@@ -402,7 +402,7 @@ local function on_step_work (self, dtime)
 		-- Do we abandon out of here now?
 	end
 
-	if self:falling(pos) then return end
+	if self:falling(pos, moveresult) then return end
 	if self:step_damage (dtime, pos) then return end
 
 	if self.state == "die" then return end
@@ -502,11 +502,11 @@ end
 
 
 -- main mob function
-function mob_class:on_step(dtime)
+function mob_class:on_step(dtime, moveresult)
 	if not DEVELOPMENT then
 		-- Removed as bundled Lua (5.1 doesn't support xpcall)
 		--local status, retVal = xpcall(on_step_work, on_step_error_handler, self, dtime)
-		local status, retVal = pcall(on_step_work, self, dtime)
+		local status, retVal = pcall(on_step_work, self, dtime, moveresult)
 		if status then
 			return retVal
 		else
@@ -521,7 +521,7 @@ function mob_class:on_step(dtime)
 			log_error (dump(retVal), dump(pos), dump(self))
 		end
 	else
-		return on_step_work (self, dtime)
+		return on_step_work (self, dtime, moveresult)
 	end
 end
 

mods/ENTITIES/mcl_mobs/init.lua

@@ -615,7 +615,7 @@ function mcl_mobs.register_egg(mob_id, desc, background_color, overlay_color, ad
 
 				pos.y = pos.y - 1
 				local mob = mcl_mobs.spawn(pos, mob_name)
-				if not object then
+				if not mob then
 					pos.y = pos.y + 1
 					mob = mcl_mobs.spawn(pos, mob_name)
 					if not mob then return end

mods/ENTITIES/mcl_mobs/physics.lua

@@ -927,7 +927,8 @@ end
 
 -- falling and fall damage
 -- returns true if mob died
-function mob_class:falling(pos)
+function mob_class:falling(pos, moveresult)
+	if moveresult and moveresult.touching_ground then return false end
 
 	if self.fly and self.state ~= "die" then
 		return

mods/ITEMS/mcl_bamboo/globals.lua

@@ -74,7 +74,7 @@ function mcl_bamboo.break_orphaned(pos)
 	local node_name = node_below.name
 
 	-- short circuit checks.
-	if mcl_bamboo.is_dirt(node_name) or mcl_bamboo.is_bamboo(node_name) or mcl_bamboo.is_bamboo(minetest.get_node(pos).name) == false then
+	if node_name == "ignore" or mcl_bamboo.is_dirt(node_name) or mcl_bamboo.is_bamboo(node_name) or mcl_bamboo.is_bamboo(minetest.get_node(pos).name) == false then
 		return
 	end
 

mods/ITEMS/mcl_chests/init.lua

@@ -79,7 +79,7 @@ minetest.register_lbm({
 		local node_name = node.name
 		node.name = node_name .. "_small"
 		minetest.swap_node(pos, node)
-		select_and_spawn_entity(pos, node)
+		mcl_chests.select_and_spawn_entity(pos, node)
 		if node_name == "mcl_chests:trapped_chest_on" then
 			minetest.log("action", "[mcl_chests] Disabled active trapped chest on load: " .. minetest.pos_to_string(pos))
 			mcl_chests.chest_update_after_close(pos)

mods/ITEMS/mcl_ocean/kelp.lua

@@ -196,7 +196,7 @@ function kelp.find_unsubmerged(pos, node, height)
 	for i=1,height do
 		walk_pos.y = y + i
 		local walk_node = mt_get_node(walk_pos)
-		if not kelp.is_submerged(walk_node) then
+		if walk_node.name ~= "ignore" and not kelp.is_submerged(walk_node) then
 			return walk_pos, walk_node, height, i
 		end
 	end