Make mcl_enchanting use the new mcl_autogroups

The function mcl_autogroups.get_groupcaps is used by mods to get the
groupcaps for tools with efficiency enchantments.  This function is used
by mcl_enchanting when enchanting tools with efficiency.

mods/CORE/_mcl_autogroup/init.lua

@@ -157,30 +157,6 @@ local function get_groupcap(group, can_harvest, multiplier, efficiency, uses)
 	}
 end
 
--- Get the groupcaps for a tool on the specified digging groups.  groupcaps_def
--- contains a table with keys being the digging group and values being the tools
--- properties for that digging group.
---
--- The tool properties can have the following values:
---
---   tool_multiplier - the digging speed multiplier for this tool (default 1)
---   efficiency - the efficiency level for this tool (default 0)
---   level - the maximum level of the group the tool can harvest (default 1)
---   uses - the number of uses the tool has for this group
---
--- A level of 0 means that the tool will be able to dig that group but will
--- never be able to harvest the nodes of that group and will always get a
--- digging time penalty.  This is useful for implementing the hand.
---
--- Example usage:
---
---   mcl_autogroup.get_groupcaps {
---       pickaxey = { tool_multiplier = 4, level = 3, uses = 132 }
---   }
---
--- This computes the groupcaps for a tool mining "pickaxey" blocks.  The tool
--- has a digging speed multiplier of 4, can mine nodes of level >= 3 and has 132
--- uses.
 local function add_groupcaps(groupcaps, groupcaps_def)
 	for g, capsdef in pairs(groupcaps_def) do
 		local mult = capsdef.tool_multiplier or 1
@@ -224,6 +200,54 @@ function mcl_autogroup.can_harvest(nodename, tool_capabilities)
 	return false
 end
 
+-- Get one groupcap field for using a specific tool on a specific group.
+local function get_groupcap(group, can_harvest, multiplier, efficiency, uses)
+	return {
+		times = get_digtimes(group, can_harvest, multiplier, efficiency),
+		uses = uses,
+		maxlevel = 0,
+	}
+end
+
+local function add_groupcaps(groupcaps, groupcaps_def, efficiency)
+	for g, capsdef in pairs(groupcaps_def) do
+		local mult = capsdef.tool_multiplier or 1
+		local eff = efficiency or 0
+		local uses = capsdef.uses
+		local def = mcl_autogroup.registered_diggroups[g]
+		local level = capsdef.level or 1
+		local max_level = def.levels or 0
+
+		if max_level > 0 then
+			level = math.min(level, max_level)
+			groupcaps[g .. "_0_dig"] = get_groupcap(g, false, mult, eff, uses)
+			groupcaps[g .. "_" .. level .. "_dig"] = get_groupcap(g, true, mult, eff, uses)
+		else
+			groupcaps[g .. "_dig"] = get_groupcap(g, true, mult, eff, uses)
+		end
+	end
+end
+
+-- Get the groupcaps for a tool.  This function returns "groupcaps" table of
+-- digging which should be put in the "tool_capabilities" of the tool definition
+-- or in the metadata of an enchanted tool.
+--
+-- Parameters:
+-- tool_name - 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]
+	local groupcaps = table.copy(tdef.tool_capabilities.groupcaps or {})
+	add_groupcaps(groupcaps, tdef._mcl_autogroup_groupcaps, efficiency)
+	return groupcaps
+end
+
 local overwrite = function()
 	for nname, ndef in pairs(minetest.registered_nodes) do
 		local newgroups = table.copy(ndef.groups)
@@ -269,9 +293,7 @@ local overwrite = function()
 		-- definition
 		if tdef._mcl_autogroup_groupcaps then
 			local toolcaps = table.copy(tdef.tool_capabilities) or {}
-			local groupcaps = toolcaps.groupcaps or {}
+			toolcaps.groupcaps = mcl_autogroup.get_groupcaps(tname)
-			groupcaps = add_groupcaps(groupcaps, tdef._mcl_autogroup_groupcaps)
-			toolcaps.groupcaps = groupcaps
 
 			minetest.override_item(tname, {
 				tool_capabilities = toolcaps

mods/CORE/mcl_autogroup/init.lua

@@ -11,6 +11,16 @@ as possible.  Minetest loads mods in reverse alphabetical order.
 mcl_autogroup = {}
 mcl_autogroup.registered_diggroups = {}
 
+-- Register a group as a digging group.
+--
+-- Parameters:
+-- group - Name of the group to register as a digging group
+-- def - Table with information about the diggroup (defaults to {} if unspecified)
+--
+-- Values in def:
+-- level - If this value is 0 or unspecified, then the group does not have
+--         levels, otherwise it is an integer greater than 0 which indicates how
+--         many digging levels the group supports.
 function mcl_autogroup.register_diggroup(group, def)
 	mcl_autogroup.registered_diggroups[group] = def or {}
 end

mods/ITEMS/mcl_enchanting/enchantments.lua

@@ -156,13 +156,7 @@ mcl_enchanting.enchantments.efficiency = {
 	curse = false,
 	on_enchant = function(itemstack, level)
 		local tool_capabilities = itemstack:get_tool_capabilities()
-		local groupcaps = {}
+		tool_capabilities.groupcaps = mcl_autogroup.get_groupcaps(itemstack:get_name(), level)
-		for group, capability in pairs(tool_capabilities.groupcaps) do
-			local groupname = group .. "_efficiency_" .. level
-			capability.times = mcl_autogroup.digtimes[groupname]
-			groupcaps[groupname] = capability
-		end
-		tool_capabilities.groupcaps = groupcaps
 		itemstack:get_meta():set_tool_capabilities(tool_capabilities)
 	end,
 	requires_tool = false,