Compare against canonical item name on pickup

mods/rp_builtin_item/README.txt

@@ -17,7 +17,7 @@ Features:
   the item entity will be instantly deleted
 * If `_rp_canonical_item` is set in the item definition, this item (itemname) will
   be used for the entity instead when it spawns. Useful when an item has multiple
-  variants ike a compass
+  variants like a compass
 
 ## Licensing
 Credits: Originally by Minetest developers (from the `builtin` part of Minetest)

mods/rp_builtin_item/init.lua

@@ -257,8 +257,9 @@ minetest.register_entity(":__builtin:item", {
 		end
 		if closest_player ~= nil and lua.item_magnet_timer <= 0 and len < ITEM_MAGNET_ACTIVE_DISTANCE then
 			local inv = closest_player:get_inventory()
+			local luastack = ItemStack(lua.itemstring)
 			-- Activate item magnet
-			if inv and inv:room_for_item("main", ItemStack(lua.itemstring)) then
+			if inv and inv:room_for_item("main", luastack) then
 				if len >= ITEM_MAGNET_COLLECT_DISTANCE then
 					-- Attract item to player
 					vec = vector.divide(vec, len) -- It's a normalize but we have len yet (vector.normalize(vec))
@@ -273,13 +274,13 @@ minetest.register_entity(":__builtin:item", {
 					return
 				else
 					-- Player collects item if close enough
-					if inv:room_for_item("main", ItemStack(lua.itemstring)) then
+					if inv:room_for_item("main", luastack) then
 						if minetest.is_creative_enabled(closest_player:get_player_name()) then
-							if not inv:contains_item("main", ItemStack(lua.itemstring), true) then
-									inv:add_item("main", ItemStack(lua.itemstring))
+							if not inv:contains_item("main", luastack, true) and not util.contains_item_canonical(inv, "main", luastack) then
+								inv:add_item("main", luastack)
 							end
 						else
-							inv:add_item("main", ItemStack(lua.itemstring))
+							inv:add_item("main", luastack)
 						end
 
 						if lua.itemstring ~= "" then

mods/rp_builtin_item/mod.conf

@@ -1 +1,2 @@
 name = rp_builtin_item
+depends = rp_util

mods/rp_item_drop/init.lua

@@ -100,7 +100,8 @@ function minetest.handle_node_drops(pos, drops, digger)
      local inv = digger:get_inventory()
      if inv then
         for _,item in ipairs(drops) do
-           if not inv:contains_item("main", item, true) then
+           item = ItemStack(item)
+           if not inv:contains_item("main", item, true) and not util.contains_item_canonical(inv, "main", item) then
               inv:add_item("main", item)
            end
         end

mods/rp_item_drop/mod.conf

@@ -1 +1,2 @@
 name = rp_item_drop
+depends = rp_util

mods/rp_util/API.md

@@ -172,3 +172,22 @@ Always returns `false` for non-nodes.
 
 Returns `true` if node at given pos is water AND either a source or a "waterfall"
 (water flowing downwards)
+
+
+
+## ` util.contains_item_canonical(inv, list, stack)`
+
+Checks if the inventory contains `stack` with the same metadata.
+Unlike `inv:contains_item`, it will treat two item names as equal
+if the *canonical name* of each item is equal.
+The canonical name of an item is specified by the item definition field
+`_rp_canonical_item`. If this is nil, the canonical item name is
+same the item name.
+
+Parameters:
+
+* `inv`: InvRef of inventory to check
+* `list`: Inventory list name
+* `stack`: ItemStack to compare to
+
+Returns `true` if a matching item was found, `false` otherwise.

mods/rp_util/init.lua

@@ -285,3 +285,42 @@ function util.is_water_source_or_waterfall(pos)
    end
    return false
 end
+
+function util.contains_item_canonical(inv, list, stack)
+   stack = ItemStack(stack)
+   if stack:is_empty() then
+      return false
+   end
+   -- Set count and wear of stack and comparison stack
+   -- to identical value because we don't care about
+   -- those
+   stack:set_count(1)
+   stack:set_wear(0)
+   local def = stack:get_definition()
+   if not def then
+      return false
+   end
+   if def._rp_canonical_item then
+      stack:set_name(def._rp_canonical_item)
+   else
+      -- If no canonical item, just use the regular contains_item check instead
+      return inv:contains_item(list, stack, true)
+   end
+   -- Iterate through all items in the list and check if the item
+   -- is equal
+   for i=1, inv:get_size(list) do
+      local cstack = inv:get_stack(list, i)
+      if not cstack:is_empty() then
+         cstack:set_count(1)
+         cstack:set_wear(0)
+         local cdef = cstack:get_definition()
+         if cdef and cdef._rp_canonical_item then
+            cstack:set_name(cdef._rp_canonical_item)
+         end
+         if stack:equals(cstack) then
+            return true
+         end
+      end
+   end
+   return false
+end