Fix many crashes when placing item on unknown node

mods/CORE/mcl_util/init.lua

@@ -252,6 +252,9 @@ function mcl_util.generate_on_place_plant_function(condition)
 		local place_pos
 		local def_under = minetest.registered_nodes[minetest.get_node(pointed_thing.under).name]
 		local def_above = minetest.registered_nodes[minetest.get_node(pointed_thing.above).name]
+		if not def_under or not def_above then
+			return itemstack
+		end
 		if def_under.buildable_to then
 			place_pos = pointed_thing.under
 		elseif def_above.buildable_to then

mods/ITEMS/REDSTONE/mesecons_button/init.lua

@@ -52,6 +52,7 @@ local on_button_place = function(itemstack, placer, pointed_thing)
 	local under = pointed_thing.under
 	local node = minetest.get_node(under)
 	local def = minetest.registered_nodes[node.name]
+	if not def then return end
 	local groups = def.groups
 
 	-- Check special rightclick action of pointed node

mods/ITEMS/bucket/init.lua

@@ -103,7 +103,7 @@ function bucket.register_liquid(source, flowing, itemname, inventory_image, name
 					sound_place("mcl_core:water_source", pos)
 				elseif item == "bucket:bucket_water" and nn == "mcl_cauldrons:cauldron_3" then
 					sound_place("mcl_core:water_source", pos)
-				elseif minetest.registered_nodes[nn].buildable_to then
+				elseif minetest.registered_nodes[nn] and minetest.registered_nodes[nn].buildable_to then
 					-- buildable; replace the node
 					local pns = user:get_player_name()
 					if minetest.is_protected(pointed_thing.under, pns) then
@@ -117,7 +117,7 @@ function bucket.register_liquid(source, flowing, itemname, inventory_image, name
 					-- not buildable to; place the liquid above
 					-- check if the node above can be replaced
 					local abovenode = minetest.get_node(pointed_thing.above)
-					if minetest.registered_nodes[abovenode.name].buildable_to then
+					if minetest.registered_nodes[abovenode.name] and minetest.registered_nodes[abovenode.name].buildable_to then
 						local pn = user:get_player_name()
 						if minetest.is_protected(pointed_thing.above, pn) then
 							return itemstack

mods/ITEMS/mcl_beds/api.lua

@@ -78,7 +78,8 @@ function mcl_beds.register_bed(name, def)
 			end
 
 			local pos
-			if minetest.registered_items[minetest.get_node(under).name].buildable_to then
+			local undername = minetest.get_node(under).name
+			if minetest.registered_items[undername] and minetest.registered_items[undername].buildable_to then
 				pos = under
 			else
 				pos = pointed_thing.above

mods/ITEMS/mcl_core/nodes.lua

@@ -1409,6 +1409,9 @@ minetest.register_node("mcl_core:ladder", {
 		local under = pointed_thing.under
 		local node = minetest.get_node(under)
 		local def = minetest.registered_nodes[node.name]
+		if not def then
+			return itemstack
+		end
 		local groups = def.groups
 
 		-- Don't allow to place the ladder at particular nodes
@@ -1483,6 +1486,7 @@ minetest.register_node("mcl_core:vine", {
 		local under = pointed_thing.under
 		local node = minetest.get_node(under)
 		local def = minetest.registered_nodes[node.name]
+		if not def then return itemstack end
 		local groups = def.groups
 
 		-- Check special rightclick action of pointed node

mods/ITEMS/mcl_doors/api_doors.lua

@@ -79,21 +79,23 @@ function mcl_doors:register_door(name, def)
 					local ptu = pointed_thing.under
 					local nu = minetest.get_node(ptu)
 					-- Pointed thing's rightclick action takes precedence, unless player holds down the sneak key
-					if minetest.registered_nodes[nu.name].on_rightclick and not placer:get_player_control().sneak then
+					if minetest.registered_nodes[nu.name] and minetest.registered_nodes[nu.name].on_rightclick and not placer:get_player_control().sneak then
 						return minetest.registered_nodes[nu.name].on_rightclick(ptu, nu, placer, itemstack)
 					end
 
 					local pt
-					if minetest.registered_nodes[minetest.get_node(ptu).name].buildable_to then
+					if minetest.registered_nodes[nu.name] and minetest.registered_nodes[nu.name].buildable_to then
 						pt = pointed_thing.under
 					else
 						pt = pointed_thing.above
 					end
 					local pt2 = {x=pt.x, y=pt.y, z=pt.z}
 					pt2.y = pt2.y+1
+					local ptname = minetest.get_node(pt).name
+					local pt2name = minetest.get_node(pt2).name
 					if
-						(not minetest.registered_nodes[minetest.get_node(pt).name].buildable_to) or
-						(not minetest.registered_nodes[minetest.get_node(pt2).name].buildable_to)
+						(minetest.registered_nodes[ptname] and not minetest.registered_nodes[ptname].buildable_to) or
+						(minetest.registered_nodes[pt2name] and not minetest.registered_nodes[pt2name].buildable_to)
 					then
 						return itemstack
 					end

mods/ITEMS/mcl_fire/flint_and_steel.lua

@@ -16,7 +16,7 @@ minetest.register_tool("mcl_fire:flint_and_steel", {
 		local used = false
 		if pointed_thing.type == "node" then
 			local nodedef = minetest.registered_nodes[minetest.get_node(pointed_thing.under).name]
-			if nodedef._on_ignite then
+			if nodedef and nodedef._on_ignite then
 				nodedef._on_ignite(pointed_thing.under, user)
 			else
 				mcl_fire.set_fire(pointed_thing)

mods/ITEMS/mcl_flowers/init.lua

@@ -186,15 +186,24 @@ local function add_large_plant(name, desc, longdesc, bottom_img, top_img, inv_im
 			-- Check for a floor and a space of 1×2×1
 			local ptu_node = minetest.get_node(pointed_thing.under)
 			local bottom
+			if not minetest.registered_nodes[ptu_node.name] then
+				return itemstack
+			end
 			if minetest.registered_nodes[ptu_node.name].buildable_to then
 				bottom = pointed_thing.under
 			else
 				bottom = pointed_thing.above
 			end
+			if not minetest.registered_nodes[minetest.get_node(bottom).name] then
+				return itemstack
+			end
 			local top = { x = bottom.x, y = bottom.y + 1, z = bottom.z }
 			local bottom_buildable = minetest.registered_nodes[minetest.get_node(bottom).name].buildable_to
 			local top_buildable = minetest.registered_nodes[minetest.get_node(top).name].buildable_to
 			local floorname = minetest.get_node({x=bottom.x, y=bottom.y-1, z=bottom.z}).name
+			if not minetest.registered_nodes[floorname] then
+				return itemstack
+			end
 
 			local light_night = minetest.get_node_light(bottom, 0.0)
 			local light_day = minetest.get_node_light(bottom, 0.5)

mods/ITEMS/mcl_hoppers/init.lua

@@ -59,7 +59,7 @@ Hoppers interact with containers the following way:
 
 		local uposnode = minetest.get_node(upos)
 		local uposnodedef = minetest.registered_nodes[uposnode.name]
-
+		if not uposnodedef then return itemstack end
 		-- Use pointed node's on_rightclick function first, if present
 		if placer and not placer:get_player_control().sneak then
 			if uposnodedef and uposnodedef.on_rightclick then
@@ -72,6 +72,7 @@ Hoppers interact with containers the following way:
 			bpos = upos
 		else
 			local aposnodedef = minetest.registered_nodes[minetest.get_node(apos).name]
+			if not aposnodedef then return itemstack end
 			if aposnodedef.buildable_to then
 				bpos = apos
 			end
@@ -207,6 +208,7 @@ minetest.register_abm({
 	chance = 1,
 	action = function(pos, node, active_object_count, active_object_count_wider)
 		local abovenode = minetest.get_node({x=pos.x, y=pos.y+1, z=pos.z})
+		if not minetest.registered_items[abovenode.name] then return end
 		-- Don't bother checking item enties if node above is a container (should save some CPU)
 		if minetest.registered_items[abovenode.name].groups.container then
 			return
@@ -281,6 +283,7 @@ minetest.register_abm({
 
 		-- Suck an item from the container above into the hopper
 		local upnode = minetest.get_node(uppos)
+		if not minetest.registered_nodes[upnode.name] then return end
 		local g = minetest.registered_nodes[upnode.name].groups.container
 		if g == 2 or g == 3 then
 			-- Typical container inventory
@@ -298,6 +301,7 @@ minetest.register_abm({
 
 		-- Move an item from the hopper into container below
 		local downnode = minetest.get_node(downpos)
+		if not minetest.registered_nodes[downnode.name] then return end
 		g = minetest.registered_nodes[downnode.name].groups.container
 		local slot_id = -1
 		if g == 3 then
@@ -338,9 +342,11 @@ minetest.register_abm({
 		local above = {x=pos.x,y=pos.y+1,z=pos.z}
 
 		local frontnode = minetest.get_node(front)
+		if not minetest.registered_nodes[frontnode.name] then return end
 
 		-- Suck an item from the container above into the hopper
 		local abovenode = minetest.get_node(above)
+		if not minetest.registered_nodes[abovenode.name] then return end
 		local g = minetest.registered_nodes[abovenode.name].groups.container
 		if g == 2 or g == 3 then
 			-- Typical container inventory

mods/ITEMS/mcl_potions/init.lua

@@ -37,7 +37,9 @@ minetest.register_craftitem("mcl_potions:glass_bottle", {
 
 			-- Try to fill glass bottle with water
 			local get_water = false
-			if def.groups and def.groups.water and def.liquidtype == "source" then
+			if not def then
+				-- Unknown node: no-op
+			elseif def.groups and def.groups.water and def.liquidtype == "source" then
 				-- Water source
 				get_water = true
 			-- Or reduce water level of cauldron by 1

mods/ITEMS/mcl_stairs/api.lua

@@ -158,7 +158,7 @@ function mcl_stairs.register_slab(subname, recipeitem, groups, images, descripti
 
 			-- combine two slabs if possible
 			-- Requirements: Same slab material, must be placed on top of lower slab, or on bottom of upper slab
-			if (wield_item == under.name or wield_item == minetest.registered_nodes[under.name]._mcl_other_slab_half) and
+			if (wield_item == under.name or (minetest.registered_nodes[under.name] and wield_item == minetest.registered_nodes[under.name]._mcl_other_slab_half)) and
 					not ((dir.y >= 0 and minetest.get_item_group(under.name, "slab_top") == 1) or
 					(dir.y <= 0 and minetest.get_item_group(under.name, "slab_top") == 0)) then
 

mods/ITEMS/mcl_throwing/throwable.lua

@@ -243,7 +243,7 @@ local pearl_on_step = function(self, dtime)
 				--[[ It may be possible that telepos is walkable due to the algorithm.
 				Especially when the ender pearl is faster horizontally than vertical.
 				This applies final fixing, just to be sure we're not in a walkable node ]]
-				if minetest.registered_nodes[telenode.name].walkable then
+				if not minetest.registered_nodes[telenode.name] or minetest.registered_nodes[telenode.name].walkable then
 					if v.y < 0 then
 						telepos.y = telepos.y + 0.5
 					else

mods/ITEMS/mcl_torches/init.lua

@@ -54,6 +54,7 @@ mcl_torches.register_torch = function(substring, description, doc_items_longdesc
 			local under = pointed_thing.under
 			local node = minetest.get_node(under)
 			local def = minetest.registered_nodes[node.name]
+			if not def then return itemstack end
 
 			-- Call on_rightclick if the pointed node defines it
 			if placer and not placer:get_player_control().sneak then