improve pummeling.

pummeling definition tables now has lists of item id:s and groups, the
same way e.g. ABM:s do, that determine what items are involved in a
recipe.

update existing (in-use) pummel recipes to make use of this.

mods/bg_crafting/pummel.lua

@@ -7,36 +7,44 @@ local pummel_recipes = {}
 function api.register_pummel_recipe (def)
 	local def = def or {}
 
-	def.label = def.label or "unnamed pummel recipe"
+	-- TODO: require `def.name` to be specified and unique.
+	def.label = def.label or "unlabeled pummel recipe"
 
 	-- TODO: throw errors when these defs are invalid instead of just returning.
-	if not def.used_item then return false end
-	if not def.target_node then return false end
+	if not def.used then return false end
+	if not def.target then return false end
 	if not type(def.on_success) == "function" then return false end
 
-	local key = def.used_item
-	def.index_key = key
-
 	def["type"] = "pummel"
 
-	pummel_recipes[key] = pummel_recipes[key] or {}
-
-	table.insert(pummel_recipes[key], def)
+	table.insert(pummel_recipes, def)
 	table.insert(api.registered_recipes, def)
 end
 
--- TODO: add support for pummel recipes using groups instead of just specific node names.
-function api.pummel_check (pos, used_item, target_node)
-	local key = used_item
-	if not pummel_recipes[key] then return false end
+-- TODO: extract these 2 functions into general api
+local function starts_with (str, start)
+	return string.sub(str, 1, string.len(start)) == start
+end
 
-	local potential_recipes = pummel_recipes[key]
-	for _, def in pairs(potential_recipes) do
-		if def.target_node == target_node.name then
-			if type(def.check) == "function" and not def.check(pos, used_item, target_node) then
+local function item_matches (nodename, options)
+	return blockgame.any(options, function (option)
+		if nodename == option then return true end
+		if starts_with(option, "group:") then
+			local group = string.sub(option, 7)
+			return minetest.get_item_group(nodename, group) > 0
+		end
+		return false
+	end)
+end
+
+-- TODO: add support for pummel recipes using groups instead of just specific node names.
+function api.pummel_check (pos, used, target_node)
+	for _, def in pairs(pummel_recipes) do
+		if item_matches(used, def.used) and item_matches(target_node.name, def.target) then
+			if type(def.check) == "function" and not def.check(pos, used, target_node) then
 				return false
 			end
-			def.on_success(pos, used_item, target_node)
+			def.on_success(pos, used, target_node)
 			return true
 		end
 	end

mods/bg_stoneworking/recipe.lua

@@ -1,9 +1,10 @@
 local modname = minetest.get_current_modname()
 
 blockgame.crafting.register_pummel_recipe({
+	name = modname .. ":craft_tile",
 	label = "pummel stone into tile",
-	used_item = "bg_terrain:cobblestone",
-	target_node = "bg_terrain:cobblestone",
+	used = {"group:stoney"},
+	target = {"bg_terrain:cobblestone"},
 	check = function (pos, used_node, target_node)
 		local below_node = minetest.get_node(pos + blockgame.vector.dirs.down)
 		local stoney_value = minetest.get_item_group(below_node.name, "stoney")
@@ -15,9 +16,10 @@ blockgame.crafting.register_pummel_recipe({
 })
 
 blockgame.crafting.register_pummel_recipe({
+	name = modname .. ":craft_bricks",
 	label = "pummel tile into bricks",
-	used_item = "bg_terrain:cobblestone",
-	target_node = modname .. ":tile",
+	used = {"group:stoney"},
+	target = {modname .. ":tile"},
 	check = function (pos, used_node, target_node)
 		local below_node = minetest.get_node(pos + blockgame.vector.dirs.down)
 		local stoney_value = minetest.get_item_group(below_node.name, "stoney")

mods/bg_woodworking/init.lua

@@ -1,2 +1,2 @@
 load_file("node")
-load_file("recipes")
+load_file("recipe")

mods/bg_woodworking/recipe.lua

@@ -1,9 +1,10 @@
 local modname = minetest.get_current_modname()
 
 blockgame.crafting.register_pummel_recipe({
-	label = "pummel log into plank",
-	used_item = "bg_terrain:cobblestone",
-	target_node = "bg_tree:log",
+	name = modname .. ":chop_log",
+	label = "chop log into plank",
+	used = {"group:stoney"},
+	target = {"bg_tree:log"},
 	check = function (pos, used_node, target_node)
 		for _, side in pairs(blockgame.vector.sides) do
 			local output_pos = pos + side