Fix tools not taking wear when rightclicking

Added the API function mcl_autogroup.get_wear which is used to get the
tool wear for digging a node of a group.  This is used by mcl_tools to
compute the wear of shovels and shears when rightclicking to create
grass paths and carve pumpkins.

mods/CORE/_mcl_autogroup/init.lua

@@ -49,6 +49,9 @@ mcl_autogroup contains the API functions used to register custom digging groups.
 _mcl_autogroup contains most of the code.  The leading underscore in the name
 "_mcl_autogroup" is used to force Minetest to load that part of the mod as late
 as possible.  Minetest loads mods in reverse alphabetical order.
+
+This also means that it is very important that no mod adds _mcl_autogroups as a
+dependency.
 --]]
 
 -- Returns a table containing the unique "_mcl_hardness" for nodes belonging to
@@ -233,21 +236,36 @@ end
 -- or in the metadata of an enchanted tool.
 --
 -- Parameters:
--- tool_name - Name of the tool being enchanted (like "mcl_tools:diamond_pickaxe")
+-- toolname - Name of the tool being enchanted (like "mcl_tools:diamond_pickaxe")
 -- efficiency - The efficiency level the tool is enchanted with (default 0)
 --
 -- NOTE: 
--- Mods calling this function (like mcl_enchanting) should _not_ have
--- _mcl_autogroups as a dependency.  It is very important that this mod is
--- loaded last.  This also means this function can only be called by other mods
--- after all mods have been initialized.
-function mcl_autogroup.get_groupcaps(tool_name, efficiency)
-	local tdef = minetest.registered_tools[tool_name]
+-- This function can only be called after mod initialization.  Otherwise a mod
+-- would have to add _mcl_autogroup as a dependency which would break the mod
+-- loading order.
+function mcl_autogroup.get_groupcaps(toolname, efficiency)
+	local tdef = minetest.registered_tools[toolname]
 	local groupcaps = table.copy(tdef.tool_capabilities.groupcaps or {})
 	add_groupcaps(groupcaps, tdef._mcl_autogroup_groupcaps, efficiency)
 	return groupcaps
 end
 
+-- Get the wear from using a tool on a digging group.
+--
+-- Parameters
+-- toolname - Name of the tool used
+-- diggroup - The name of the diggroup the tool is used on
+--
+-- NOTE: 
+-- This function can only be called after mod initialization.  Otherwise a mod
+-- would have to add _mcl_autogroup as a dependency which would break the mod
+-- loading order.
+function mcl_autogroup.get_wear(toolname, diggroup)
+	local tdef = minetest.registered_tools[toolname]
+	local uses = tdef._mcl_autogroup_groupcaps[diggroup].uses
+	return math.ceil(65535 / uses)
+end
+
 local overwrite = function()
 	for nname, ndef in pairs(minetest.registered_nodes) do
 		local newgroups = table.copy(ndef.groups)

mods/ITEMS/mcl_tools/init.lua

@@ -179,26 +179,6 @@ minetest.register_tool("mcl_tools:pick_diamond", {
 	},
 })
 
-local get_shovel_dig_group = function(itemstack)
-	local itemstring = itemstack:get_name()
-	local efficiency_level = mcl_enchanting.get_enchantment(itemstack, "efficiency")
-	local postfix = efficiency_level > 0 and "_efficiency_" .. efficiency_level or ""
-	if itemstring:find("mcl_tools:shovel_wood") == 1 then
-		return "shovely_dig_wood" .. postfix
-	elseif itemstring:find("mcl_tools:shovel_stone") == 1 then
-		return "shovely_dig_stone" .. postfix
-	elseif itemstring:find("mcl_tools:shovel_iron") == 1 then
-		return "shovely_dig_iron" .. postfix
-	elseif itemstring:find("mcl_tools:shovel_gold") == 1 then
-		return "shovely_dig_gold" .. postfix
-	elseif itemstring:find("mcl_tools:shovel_diamond") == 1 then
-		return "shovely_dig_diamond" .. postfix
-	else
-		-- Fallback
-		return "shovely_dig_wood"
-	end
-end
-
 local make_grass_path = function(itemstack, placer, pointed_thing)
 	-- Use pointed node's on_rightclick function first, if present
 	local node = minetest.get_node(pointed_thing.under)
@@ -223,15 +203,9 @@ local make_grass_path = function(itemstack, placer, pointed_thing)
 			end
 
 			if not minetest.is_creative_enabled(placer:get_player_name()) then
-				-- Add wear, as if digging a level 0 shovely node
+				-- Add wear (as if digging a shovely node)
 				local toolname = itemstack:get_name()
-				local def = minetest.registered_items[toolname]
-				local group = get_shovel_dig_group(itemstack)
-				local toolcaps = itemstack:get_tool_capabilities()
-				local base_uses = toolcaps.groupcaps[group].uses
-				local maxlevel = toolcaps.groupcaps[group].maxlevel
-				local uses = base_uses * math.pow(3, maxlevel)
-				local wear = math.ceil(65535 / uses)
+				local wear = mcl_autogroup.get_wear(toolname, "shovely")
 				itemstack:add_wear(wear)
 			end
 			minetest.sound_play({name="default_grass_footstep", gain=1}, {pos = above}, true)
@@ -260,12 +234,7 @@ if minetest.get_modpath("mcl_farming") then
 			if not minetest.is_creative_enabled(placer:get_player_name()) then
 				-- Add wear (as if digging a shearsy node)
 				local toolname = itemstack:get_name()
-				local def = minetest.registered_items[toolname]
-				local group = get_shovel_dig_group(toolname)
-				local base_uses = def.tool_capabilities.groupcaps["shearsy_dig"].uses
-				local maxlevel = def.tool_capabilities.groupcaps["shearsy_dig"].maxlevel
-				local uses = base_uses * math.pow(3, maxlevel)
-				local wear = math.ceil(65535 / uses)
+				local wear = mcl_autogroup.get_wear(toolname, "shearsy")
 				itemstack:add_wear(wear)
 			end
 			minetest.sound_play({name="default_grass_footstep", gain=1}, {pos = above}, true)