Fix crash when loading schematic in a LuaJIT build in recent Minetest…

… versions (thanks LazyJ & VanessaE!).

worldedit/serialization.lua

@@ -158,21 +158,23 @@ function worldedit.load_schematic(value)
 			-- This is broken for larger tables in the current version of LuaJIT
 			nodes = minetest.deserialize(content)
 		else
-			-- XXX: This is a filthy hack that works surprisingly well
+			-- XXX: This is a filthy hack that works surprisingly well - in LuaJIT, `minetest.deserialize` will fail due to the register limit
 			nodes = {}
-			value = value:gsub("return%s*{", "", 1):gsub("}%s*$", "", 1)
+			value = value:gsub("return%s*{", "", 1):gsub("}%s*$", "", 1) -- remove the starting and ending values to leave only the node data
 			local escaped = value:gsub("\\\\", "@@"):gsub("\\\"", "@@"):gsub("(\"[^\"]*\")", function(s) return string.rep("@", #s) end)
 			local startpos, startpos1, endpos = 1, 1
-			while true do
+			while true do -- go through each individual node entry (except the last)
 				startpos, endpos = escaped:find("},%s*{", startpos)
 				if not startpos then
 					break
 				end
 				local current = value:sub(startpos1, startpos)
-				table.insert(nodes, minetest.deserialize("return " .. current))
+				local entry = minetest.deserialize("return " .. current)
+				table.insert(nodes, entry)
 				startpos, startpos1 = endpos, endpos
 			end
-			table.insert(nodes, minetest.deserialize("return " .. value:sub(startpos1)))
+			local entry = minetest.deserialize("return " .. value:sub(startpos1)) -- process the last entry
+			table.insert(nodes, entry)
 		end
 	else
 		return nil