Prevent null concatenation when /deleteblocks is provided an incorrect format

[minetest.git] / builtin / game / register.lua

diff --git a/builtin/game/register.lua b/builtin/game/register.lua
index f7ebdee9a321597be9f8aa4aa40a177f6ad6180a..f286113ec8d335bd20c0ade04e78bbcd001c1790 100644 (file)
--- a/builtin/game/register.lua
+++ b/builtin/game/register.lua
@@ -226,13 +226,6 @@ function core.register_alias(name, convert_to)
        end
 end
 
-local register_biome_raw = core.register_biome
-core.registered_biomes = {}
-function core.register_biome(biome)
-       core.registered_biomes[biome.name] = biome
-       register_biome_raw(biome)
-end
-
 function core.on_craft(itemstack, player, old_craft_list, craft_inv)
        for _, func in ipairs(core.registered_on_crafts) do
                itemstack = func(itemstack, player, old_craft_list, craft_inv) or itemstack
@@ -387,6 +380,35 @@ local function make_registration_reverse()
        return t, registerfunc
 end
 
+local function make_registration_wrap(reg_fn_name, clear_fn_name)
+       local list = {}
+
+       local orig_reg_fn = core[reg_fn_name]
+       core[reg_fn_name] = function(def)
+               local retval = orig_reg_fn(def)
+               if retval ~= nil then
+                       if def.name ~= nil then
+                               list[def.name] = def
+                       else
+                               list[retval] = def
+                       end
+               end
+               return retval
+       end
+
+       local orig_clear_fn = core[clear_fn_name]
+       core[clear_fn_name] = function()
+               list = {}
+               return orig_clear_fn()
+       end
+
+       return list
+end
+
+core.registered_biomes      = make_registration_wrap("register_biome",      "clear_registered_biomes")
+core.registered_ores        = make_registration_wrap("register_ore",        "clear_registered_ores")
+core.registered_decorations = make_registration_wrap("register_decoration", "clear_registered_decorations")
+
 core.registered_on_chat_messages, core.register_on_chat_message = make_registration()
 core.registered_globalsteps, core.register_globalstep = make_registration()
 core.registered_playerevents, core.register_playerevent = make_registration()