From 3e1c1ca20800cfed87ee0c825661e6b579a1a6f5 Mon Sep 17 00:00:00 2001
From: Buckaroo Banzai <39065740+BuckarooBanzay@users.noreply.github.com>
Date: Mon, 19 Jun 2023 07:44:40 +0200
Subject: [PATCH] add luacheck and ci workflow (#88)

* add luacheck and ci workflow

* fix another bunch

* more fixes

* more fixes

* regex magic

* add deps

* doc.lua special rules

* more regex magic

* final fixes

---------

Co-authored-by: BuckarooBanzay <BuckarooBanzay@users.noreply.github.com>
---
 .github/workflows/luacheck.yml |  17 +++
 .luacheckrc                    |  27 +++++
 awards.lua                     |  16 +--
 class_fakeplayer.lua           |  32 +++---
 class_layout.lua               | 110 +++++++++----------
 class_pointset.lua             |  35 +++---
 doc.lua                        |   4 +-
 entities.lua                   |  71 ++++++------
 init.lua                       |   5 +-
 nodes/node_axle.lua            |  16 +--
 nodes/node_battery_holder.lua  |  34 +++---
 nodes/node_builders.lua        | 194 ++++++++++++++++-----------------
 nodes/node_controllers.lua     |  95 ++++++++--------
 nodes/node_crate.lua           | 100 +++++++++--------
 nodes/node_diggers.lua         | 101 ++++++++---------
 nodes/node_duplicator.lua      |  13 ++-
 nodes/node_item_ejector.lua    |  46 ++++----
 nodes/node_misc.lua            |   2 +-
 nodes/node_power_connector.lua |  40 ++++---
 nodes/node_storage.lua         |  69 ++++++------
 nodes/recipes.lua              |   4 +-
 upgrades.lua                   |   8 +-
 util.lua                       |  55 +++++-----
 util_execute_cycle.lua         | 161 +++++++++++++--------------
 util_item_place_node.lua       |  19 ++--
 25 files changed, 669 insertions(+), 605 deletions(-)
 create mode 100644 .github/workflows/luacheck.yml
 create mode 100644 .luacheckrc

diff --git a/.github/workflows/luacheck.yml b/.github/workflows/luacheck.yml
new file mode 100644
index 0000000..1effc90
--- /dev/null
+++ b/.github/workflows/luacheck.yml
@@ -0,0 +1,17 @@
+name: luacheck
+
+on: [push, pull_request]
+
+jobs:
+  build:
+
+    runs-on: ubuntu-latest
+
+    steps:
+    - uses: actions/checkout@master
+    - name: apt
+      run: sudo apt-get install -y luarocks
+    - name: luacheck install
+      run: luarocks install --local luacheck
+    - name: luacheck run
+      run: $HOME/.luarocks/bin/luacheck ./
diff --git a/.luacheckrc b/.luacheckrc
new file mode 100644
index 0000000..d28b414
--- /dev/null
+++ b/.luacheckrc
@@ -0,0 +1,27 @@
+max_line_length = 200
+
+globals = {
+	"digtron",
+	"catacomb"
+}
+
+read_globals = {
+	-- Stdlib
+	string = {fields = {"split"}},
+	table = {fields = {"copy", "getn"}},
+	"VoxelManip",
+
+	-- Minetest
+	"minetest",
+	"vector", "ItemStack",
+	"dump", "VoxelArea",
+
+	-- Deps
+	"default", "awards", "pipeworks", "hopper", "technic", "doc", "intllib"
+}
+
+files = {
+	["doc.lua"] = {
+		max_line_length = 1000
+	}
+}
\ No newline at end of file
diff --git a/awards.lua b/awards.lua
index 074fe3b..376bff5 100644
--- a/awards.lua
+++ b/awards.lua
@@ -1,8 +1,8 @@
 if not minetest.get_modpath("awards") then
-	digtron.award_item_dug = function (items, name, count) end
-	digtron.award_layout = function (layout, name) end
-	digtron.award_item_built = function(item_name, name) end
-	digtron.award_crate = function (layout, name) end
+	digtron.award_item_dug = function() end
+	digtron.award_layout = function() end
+	digtron.award_item_built = function() end
+	digtron.award_crate = function() end
 	return
 end
 
@@ -10,14 +10,14 @@ end
 
 -- internationalization boilerplate
 local MP = minetest.get_modpath(minetest.get_current_modname())
-local S, NS = dofile(MP.."/intllib.lua")
+local S = dofile(MP.."/intllib.lua")
 
 awards.register_trigger("digtron_dig", {
 	type = "counted_key",
 	progress = "@1/@2 excavated",
 	auto_description = {"Excavate 1 @2 using a Digtron.", "Excavate @1 @2 using a Digtron."},
 	auto_description_total = {"Excavate @1 block using a Digtron.", "Excavate @1 blocks using a Digtron."},
-	get_key = function(self, def)
+	get_key = function(_, def)
 		return minetest.registered_aliases[def.trigger.node] or def.trigger.node
 	end,
 	key_is_item = true,
@@ -37,7 +37,7 @@ awards.register_trigger("digtron_build", {
 	progress = "@1/@2 built",
 	auto_description = {"Build 1 @2 using a Digtron.", "Build @1 @2 using a Digtron."},
 	auto_description_total = {"Build @1 block using a Digtron.", "Build @1 blocks using a Digtron."},
-	get_key = function(self, def)
+	get_key = function(_, def)
 		return minetest.registered_aliases[def.trigger.node] or def.trigger.node
 	end,
 	key_is_item = true,
@@ -75,7 +75,7 @@ digtron.award_layout = function(layout, player)
 	if layout.builders ~= nil and table.getn(layout.builders) > 24 then
 		awards.unlock(name, "digtron_builder25")
 	end
-	
+
 	if layout.controller.y > 100 then
 		awards.unlock(name, "digtron_height100")
 		if layout.controller.y > 1000 then
diff --git a/class_fakeplayer.lua b/class_fakeplayer.lua
index 7976cb4..91c8d32 100644
--- a/class_fakeplayer.lua
+++ b/class_fakeplayer.lua
@@ -2,15 +2,15 @@
 -- demand a "Player" object as a parameter and hopefully prevent the mods that have
 -- registered with those callbacks from crashing on a nil dereference or bad function
 -- call. This is not supposed to be a remotely functional thing, it's just supposed
--- to provide dummy methods and return values of the correct data type for anything that 
+-- to provide dummy methods and return values of the correct data type for anything that
 -- might ignore the false "is_player()" return and go ahead and try to use this thing
 -- anyway.
 
 -- I'm trying to patch holes in bad mod programming, essentially. If a mod is so badly
 -- programmed that it crashes anyway there's not a lot else I can do on my end of things.
 
-DigtronFakePlayer = {}
-DigtronFakePlayer.__index = DigtronFakePlayer
+digtron.DigtronFakePlayer = {}
+digtron.DigtronFakePlayer.__index = digtron.DigtronFakePlayer
 
 local function return_value(x)
 	return (function() return x end)
@@ -32,18 +32,18 @@ local function return_empty_table()
 	return {}
 end
 
-function DigtronFakePlayer.update(self, pos, player_name)
+function digtron.DigtronFakePlayer.update(self, pos, player_name)
 	self.is_fake_player = ":digtron " .. player_name
 	self.get_pos = return_value(pos)
 end
 
-function DigtronFakePlayer.create(pos, player_name)
+function digtron.DigtronFakePlayer.create(pos, player_name)
 	local self = {}
-	setmetatable(self, DigtronFakePlayer)
-	
+	setmetatable(self, digtron.DigtronFakePlayer)
+
 	self.is_fake_player = ":digtron " .. player_name
 
-	-- ObjectRef	
+	-- ObjectRef
 	self.get_pos = return_value(pos)
 	self.set_pos = return_nil
 	self.move_to = return_nil
@@ -87,7 +87,6 @@ function DigtronFakePlayer.create(pos, player_name)
 	self.get_luaentity = return_nil
 
 	-- Player object
-	
 	self.get_player_name = return_empty_string
 	self.get_player_velocity = return_nil
 	self.get_look_dir = return_value({x=0,y=1,z=0})
@@ -112,13 +111,12 @@ function DigtronFakePlayer.create(pos, player_name)
 
 	self.set_physics_override = return_nil
 	self.get_physics_override = return_value({speed = 1, jump = 1, gravity = 1, sneak = true, sneak_glitch = false, new_move = true,})
-	
-	
+
 	self.hud_add = return_nil
 	self.hud_remove = return_nil
 	self.hud_change = return_nil
 	self.hud_get = return_nil -- possibly important return value?
-	self.hud_set_flags = return_nil	
+	self.hud_set_flags = return_nil
 	self.hud_get_flags = return_value({ hotbar=true, healthbar=true, crosshair=true, wielditem=true, breathbar=true, minimap=true })
 	self.hud_set_hotbar_itemcount = return_nil
 	self.hud_get_hotbar_itemcount = return_zero
@@ -128,18 +126,18 @@ function DigtronFakePlayer.create(pos, player_name)
 	self.hud_get_hotbar_selected_image = return_empty_string
 	self.set_sky = return_nil
 	self.get_sky = return_empty_table -- may need members on this table
-	
+
 	self.set_clouds = return_nil
 	self.get_clouds = return_value({density = 0, color = "#fff0f0e5", ambient = "#000000", height = 120, thickness = 16, speed = {x=0, y=-2}})
-	
+
 	self.override_day_night_ratio = return_nil
 	self.get_day_night_ratio = return_nil
-	
+
 	self.set_local_animation = return_nil
 	self.get_local_animation = return_empty_table
-	
+
 	self.set_eye_offset = return_nil
 	self.get_eye_offset = return_value({x=0,y=0,z=0},{x=0,y=0,z=0})
-	
+
 	return self
 end
\ No newline at end of file
diff --git a/class_layout.lua b/class_layout.lua
index 1fc0749..678aed2 100644
--- a/class_layout.lua
+++ b/class_layout.lua
@@ -1,7 +1,5 @@
-DigtronLayout = {}
-DigtronLayout.__index = DigtronLayout
-
-local modpath_awards = minetest.get_modpath("awards")
+digtron.DigtronLayout = {}
+digtron.DigtronLayout.__index = digtron.DigtronLayout
 
 -------------------------------------------------------------------------
 -- Creation
@@ -15,7 +13,7 @@ local get_node_image = function(pos, node)
 	if node_image.meta ~= nil and node_def._digtron_formspec ~= nil then
 		node_image.meta.fields.formspec = node_def._digtron_formspec(pos, meta) -- causes formspec to be automatically upgraded whenever Digtron moves
 	end
-	
+
 	local group = minetest.get_item_group(node.name, "digtron")
 	-- group 1 has no special metadata
 	if group > 1 and group < 10 then
@@ -27,7 +25,7 @@ local get_node_image = function(pos, node)
 			.. tostring(group) .. ". This error should not be possible. Please see https://github.com/minetest/minetest/issues/8067")
 		end
 	end
-	
+
 	-- Record what kind of thing we've got in a builder node so its facing can be rotated properly
 	if group == 4 then
 		local build_item = ""
@@ -45,25 +43,27 @@ local get_node_image = function(pos, node)
 end
 
 -- temporary pointsets used while searching
-local to_test = Pointset.create()
-local tested = Pointset.create()
+local to_test = digtron.Pointset.create()
+local tested = digtron.Pointset.create()
 
-function DigtronLayout.create(pos, player)
+function digtron.DigtronLayout.create(pos, player)
 	local self = {}
-	setmetatable(self, DigtronLayout)
+	setmetatable(self, digtron.DigtronLayout)
 
 	--initialize. We're assuming that the start position is a controller digtron, should be a safe assumption since only the controller node should call this
 	self.traction = 0
 	self.all = {}
 	self.water_touching = false
 	self.lava_touching = false
-	self.protected = Pointset.create() -- if any nodes we look at are protected, make note of that. That way we don't need to keep re-testing protection state later.
-	self.old_pos_pointset = Pointset.create() -- For tracking original location of nodes if we do transformations on the Digtron
-	self.nodes_dug = Pointset.create() -- For tracking adjacent nodes that will have been dug by digger heads in future
+	self.protected = digtron.Pointset.create() -- if any nodes we look at are protected, make note of that. That way we don't need to keep re-testing protection state later.
+	self.old_pos_pointset = digtron.Pointset.create() -- For tracking original location of nodes if we do transformations on the Digtron
+	self.nodes_dug = digtron.Pointset.create() -- For tracking adjacent nodes that will have been dug by digger heads in future
 	self.contains_protected_node = false -- used to indicate if at least one node in this digtron array is protected from the player.
 	self.controller = {x=pos.x, y=pos.y, z=pos.z} 	--Make a deep copy of the pos parameter just in case the calling code wants to play silly buggers with it
 
-	table.insert(self.all, get_node_image(pos, minetest.get_node(pos))) -- We never visit the source node, so insert it into the all table a priori. Revisit this design decision if a controller node is created that contains fuel or inventory or whatever.
+	-- We never visit the source node, so insert it into the all table a priori.
+	-- Revisit this design decision if a controller node is created that contains fuel or inventory or whatever.
+	table.insert(self.all, get_node_image(pos, minetest.get_node(pos)))
 
 	self.extents_max_x = pos.x
 	self.extents_min_x = pos.x
@@ -79,12 +79,12 @@ function DigtronLayout.create(pos, player)
 	to_test:set(pos.x, pos.y - 1, pos.z, true)
 	to_test:set(pos.x, pos.y, pos.z + 1, true)
 	to_test:set(pos.x, pos.y, pos.z - 1, true)
-	
+
 	if minetest.is_protected(pos, player:get_player_name()) and not minetest.check_player_privs(player, "protection_bypass") then
 		self.protected:set(pos.x, pos.y, pos.z, true)
 		self.contains_protected_node = true
 	end
-	
+
 	-- Do a loop on to_test positions, adding new to_test positions as we find digtron nodes. This is a flood fill operation
 	-- that follows node faces (no diagonals)
 	local testpos, _ = to_test:pop()
@@ -96,7 +96,7 @@ function DigtronLayout.create(pos, player)
 			--digtron array is next to unloaded nodes, too dangerous to do anything. Abort.
 			self.ignore_touching = true
 		end
-		
+
 		if minetest.get_item_group(node.name, "water") ~= 0 then
 			self.water_touching = true
 		elseif minetest.get_item_group(node.name, "lava") ~= 0 then
@@ -111,12 +111,12 @@ function DigtronLayout.create(pos, player)
 			self.protected:set(testpos.x, testpos.y, testpos.z, true)
 			is_protected = true
 		end
-		
+
 		local group_number = minetest.get_item_group(node.name, "digtron")
 		if group_number > 0 then
 			--found one. Add it to the digtrons output
 			local node_image = get_node_image(testpos, node)
-			
+
 			table.insert(self.all, node_image)
 
 			-- add a reference to this node's position to special node lists
@@ -147,11 +147,11 @@ function DigtronLayout.create(pos, player)
 				self.auto_ejectors = self.auto_ejectors or {}
 				table.insert(self.auto_ejectors, node_image)
 			end
-			
+
 			if is_protected then
 				self.contains_protected_node = true
 			end
-			
+
 			-- update extents
 			self.extents_max_x = math.max(self.extents_max_x, testpos.x)
 			self.extents_min_x = math.min(self.extents_min_x, testpos.x)
@@ -159,7 +159,7 @@ function DigtronLayout.create(pos, player)
 			self.extents_min_y = math.min(self.extents_min_y, testpos.y)
 			self.extents_max_z = math.max(self.extents_max_z, testpos.z)
 			self.extents_min_z = math.min(self.extents_min_z, testpos.z)
-			
+
 			--queue up potential new test points adjacent to this digtron node
 			to_test:set_if_not_in(tested, testpos.x + 1, testpos.y, testpos.z, true)
 			to_test:set_if_not_in(tested, testpos.x - 1, testpos.y, testpos.z, true)
@@ -172,15 +172,15 @@ function DigtronLayout.create(pos, player)
 			-- Allowing unknown nodes to provide traction, since they're not buildable_to either
 			self.traction = self.traction + 1
 		end
-		
+
 		testpos, _ = to_test:pop()
 	end
-	
+
 	digtron.award_layout(self, player) -- hook for achievements mod
-	
+
 	to_test:clear()
 	tested:clear()
-	
+
 	return self
 end
 
@@ -245,7 +245,7 @@ local rotate_pos = function(axis, direction, pos)
 			pos.x = pos.z
 			pos.z = -temp_x
 		end
-	else	
+	else
 		if direction < 0 then
 			local temp_x = pos.x
 			pos.x = -pos.y
@@ -280,25 +280,25 @@ local rotate_node_image = function(node_image, origin, axis, direction, old_pos_
 	elseif node_image.paramtype2 == "facedir" then
 		node_image.node.param2 = facedir_rotate[axis][direction][node_image.node.param2]
 	end
-	
+
 	if node_image.build_item_paramtype2 == "wallmounted" then
 		node_image.meta.fields.build_facing = wallmounted_rotate[axis][direction][tonumber(node_image.meta.fields.build_facing)]
 	elseif node_image.build_item_paramtype2 == "facedir" then
 		node_image.meta.fields.build_facing = facedir_rotate[axis][direction][tonumber(node_image.meta.fields.build_facing)]
 	end
-	
+
 	node_image.meta.fields.waiting = nil -- If we're rotating a controller that's in the "waiting" state, clear it. Otherwise it may stick like that.
 
 	-- record the old location so we can destroy the old node if the rotation operation is possible
 	old_pos_pointset:set(node_image.pos.x, node_image.pos.y, node_image.pos.z, true)
-	
+
 	-- position in space relative to origin
 	local pos = subtract_in_place(node_image.pos, origin)
 	pos = rotate_pos(axis, direction, pos)
 	-- Move back to original reference frame
 	node_image.pos = add_in_place(pos, origin)
-	
-	return node_image	
+
+	return node_image
 end
 
 
@@ -311,7 +311,7 @@ local top = {
 	{axis="y", dir=1},
 }
 -- Rotates 90 degrees widdershins around the axis defined by facedir (which in this case is pointing out the front of the node, so it needs to be converted into an upward-pointing axis internally)
-function DigtronLayout.rotate_layout_image(self, facedir)
+function digtron.DigtronLayout.rotate_layout_image(self, facedir)
 
 	if self == nil or self.all == nil or self.controller == nil or self.old_pos_pointset == nil then
 		-- this should not be possible, but if it is then abort.
@@ -325,10 +325,10 @@ function DigtronLayout.rotate_layout_image(self, facedir)
 	-- 12, 13, 14, 15 == (1,0,0)
 	-- 16, 17, 18, 19 == (-1,0,0)
 	-- 20, 21, 22, 23== (0,-1,0)
-	
+
 	local params = top[math.floor(facedir/4)]
-	
-	for k, node_image in pairs(self.all) do
+
+	for _, node_image in pairs(self.all) do
 		rotate_node_image(node_image, self.controller, params.axis, params.dir, self.old_pos_pointset)
 	end
 	return self
@@ -337,15 +337,15 @@ end
 -----------------------------------------------------------------------------------------------
 -- Translation
 
-function DigtronLayout.move_layout_image(self, dir)
+function digtron.DigtronLayout.move_layout_image(self, dir)
 	self.extents_max_x = self.extents_max_x + dir.x
 	self.extents_min_x = self.extents_min_x + dir.x
 	self.extents_max_y = self.extents_max_y + dir.y
 	self.extents_min_y = self.extents_min_y + dir.y
 	self.extents_max_z = self.extents_max_z + dir.z
 	self.extents_min_z = self.extents_min_z + dir.z
-	
-	for k, node_image in pairs(self.all) do
+
+	for _, node_image in pairs(self.all) do
 		self.old_pos_pointset:set(node_image.pos.x, node_image.pos.y, node_image.pos.z, true)
 		node_image.pos = add_in_place(node_image.pos, dir)
 		self.nodes_dug:set(node_image.pos.x, node_image.pos.y, node_image.pos.z, false) -- we've moved a digtron node into this space, mark it so that we don't dig it.
@@ -355,8 +355,8 @@ end
 -----------------------------------------------------------------------------------------------
 -- Writing to world
 
-function DigtronLayout.can_write_layout_image(self)
-	for k, node_image in pairs(self.all) do
+function digtron.DigtronLayout.can_write_layout_image(self)
+	for _, node_image in pairs(self.all) do
 		--check if we're moving into a protected node
 		if self.protected:get(node_image.pos.x, node_image.pos.y, node_image.pos.z) then
 			return false
@@ -394,14 +394,14 @@ local node_callbacks = function(player)
 			local old_pos = dug_node_pos[i]
 			local old_node = dug_node[i]
 			local old_meta = dug_node_meta[i]
-	
+
 			for _, callback in ipairs(minetest.registered_on_dignodes) do
 				-- Copy pos and node because callback can modify them
 				local pos_copy = {x=old_pos.x, y=old_pos.y, z=old_pos.z}
 				local oldnode_copy = {name=old_node.name, param1=old_node.param1, param2=old_node.param2}
 				callback(pos_copy, oldnode_copy, digtron.fake_player)
 			end
-	
+
 			local old_def = minetest.registered_nodes[old_node.name]
 			if old_def ~= nil and old_def.after_dig_node ~= nil then
 				old_def.after_dig_node(old_pos, old_node, old_meta, player)
@@ -414,7 +414,7 @@ local node_callbacks = function(player)
 			local new_pos = placed_node_pos[i]
 			local new_node = placed_new_node[i]
 			local old_node = placed_old_node[i]
-	
+
 			for _, callback in ipairs(minetest.registered_on_placenodes) do
 				-- Copy pos and node because callback can modify them
 				local pos_copy = {x=new_pos.x, y=new_pos.y, z=new_pos.z}
@@ -422,7 +422,7 @@ local node_callbacks = function(player)
 				local newnode_copy = {name=new_node.name, param1=new_node.param1, param2=new_node.param2}
 				callback(pos_copy, newnode_copy, digtron.fake_player, oldnode_copy)
 			end
-	
+
 			local new_def = minetest.registered_nodes[new_node.name]
 			if new_def ~= nil and new_def.after_place_node ~= nil then
 				new_def.after_place_node(new_pos, player)
@@ -452,7 +452,7 @@ local set_meta_with_retry = function(meta, meta_table)
 end
 
 local air_node = {name="air"}
-function DigtronLayout.write_layout_image(self, player)
+function digtron.DigtronLayout.write_layout_image(self, player)
 	-- destroy the old digtron
 	local oldpos, _ = self.old_pos_pointset:pop()
 	while oldpos ~= nil do
@@ -472,7 +472,7 @@ function DigtronLayout.write_layout_image(self, player)
 	end
 
 	-- create the new one
-	for k, node_image in pairs(self.all) do
+	for _, node_image in pairs(self.all) do
 		local new_pos = node_image.pos
 		local new_node = node_image.node
 		local old_node = minetest.get_node(new_pos)
@@ -481,13 +481,13 @@ function DigtronLayout.write_layout_image(self, player)
 			minetest.log("error", "DigtronLayout.write_layout_image failed to write a Digtron node, aborting write.")
 			return false
 		end
-		
+
 		placed_nodes_count = placed_nodes_count + 1
 		placed_node_pos[placed_nodes_count] = new_pos
 		placed_new_node[placed_nodes_count] = new_node
 		placed_old_node[placed_nodes_count] = old_node
 	end
-	
+
 	-- fake_player will be passed to callbacks to prevent actual player from "taking the blame" for this action.
 	-- For example, the hunger mod shouldn't be making the player hungry when he moves Digtron.
 	digtron.fake_player:update(self.controller, player:get_player_name())
@@ -502,10 +502,10 @@ end
 ---------------------------------------------------------------------------------------------
 -- Serialization. Currently only serializes the data that is needed by the crate, upgrade this function if more is needed
 
-function DigtronLayout.serialize(self)
+function digtron.DigtronLayout.serialize(self)
 	-- serialize can't handle ItemStack objects, convert them to strings.
 	for _, node_image in pairs(self.all) do
-		for k, inv in pairs(node_image.meta.inventory) do
+		for _, inv in pairs(node_image.meta.inventory) do
 			for index, item in pairs(inv) do
 				inv[index] = item:to_string()
 			end
@@ -515,10 +515,10 @@ function DigtronLayout.serialize(self)
 	return minetest.serialize({controller=self.controller, all=self.all})
 end
 
-function DigtronLayout.deserialize(layout_string)
+function digtron.DigtronLayout.deserialize(layout_string)
 	local self = {}
-	setmetatable(self, DigtronLayout)
-	
+	setmetatable(self, digtron.DigtronLayout)
+
 	if not layout_string or layout_string == "" then
 		return nil
 	end
@@ -526,7 +526,7 @@ function DigtronLayout.deserialize(layout_string)
 
 	self.all = deserialized_layout.all
 	self.controller = deserialized_layout.controller
-	self.old_pos_pointset = Pointset.create() -- needed by the write_layout method, leave empty
+	self.old_pos_pointset = digtron.Pointset.create() -- needed by the write_layout method, leave empty
 
 	return self
 end
diff --git a/class_pointset.lua b/class_pointset.lua
index 40663d6..032555b 100644
--- a/class_pointset.lua
+++ b/class_pointset.lua
@@ -1,7 +1,7 @@
 -- A simple special-purpose class, this is used for building up sets of three-dimensional points for fast reference
 
-Pointset = {}
-Pointset.__index = Pointset
+digtron.Pointset = {}
+digtron.Pointset.__index = digtron.Pointset
 
 -- from builtin\game\misc.lua, modified to take values directly to avoid creating an intermediate vector
 local hash_node_position_values = function(x, y, z)
@@ -10,26 +10,26 @@ local hash_node_position_values = function(x, y, z)
 		 +  x + 32768
 end
 
-function Pointset.create()
+function digtron.Pointset.create()
 	local set = {}
-	setmetatable(set,Pointset)
+	setmetatable(set,digtron.Pointset)
 	set.points = {}
 	return set
 end
 
-function Pointset:clear()
+function digtron.Pointset:clear()
 	local points = self.points
-	for k, v in pairs(points) do
+	for k in pairs(points) do
 		points[k] = nil
 	end
 end
 
-function Pointset:set(x, y, z, value)
+function digtron.Pointset:set(x, y, z, value)
 	-- sets a value in the 3D array "points".
 	self.points[hash_node_position_values(x,y,z)] = value
 end
 
-function Pointset:set_if_not_in(excluded, x, y, z, value)
+function digtron.Pointset:set_if_not_in(excluded, x, y, z, value)
 	-- If a value is not already set for this point in the 3D array "excluded", set it in "points"
 	if excluded:get(x, y, z) ~= nil then
 		return
@@ -37,34 +37,35 @@ function Pointset:set_if_not_in(excluded, x, y, z, value)
 	self:set(x, y, z, value)
 end
 
-function Pointset:get(x, y, z)
+function digtron.Pointset:get(x, y, z)
 	-- return a value from the 3D array "points"
 	return self.points[hash_node_position_values(x,y,z)]
 end
 
-function Pointset:set_pos(pos, value)
+function digtron.Pointset:set_pos(pos, value)
 	self:set(pos.x, pos.y, pos.z, value)
 end
 
-function Pointset:set_pos_if_not_in(excluded, pos, value)
+function digtron.Pointset:set_pos_if_not_in(excluded, pos, value)
 	self:set_if_not_in(excluded, pos.x, pos.y, pos.z, value)
 end
 
-function Pointset:get_pos(pos)
+function digtron.Pointset:get_pos(pos)
 	return self:get(pos.x, pos.y, pos.z)
 end
 
-function Pointset:pop()
+function digtron.Pointset:pop()
 	-- returns a point that's in the 3D array, and then removes it.
 	local hash, value = next(self.points)
 	if hash == nil then return nil end
 	local pos = minetest.get_position_from_hash(hash)
-	self.points[hash] = nil	
+	self.points[hash] = nil
 	return pos, value
 end
 
-function Pointset:get_pos_list(value)
-	-- Returns a list of all points with the given value in standard Minetest vector format. If no value is provided, returns all points
+function digtron.Pointset:get_pos_list(value)
+	-- Returns a list of all points with the given value in standard Minetest vector format.
+	-- If no value is provided, returns all points
 	local outlist = {}
 	for hash, pointsval in pairs(self.points) do
 		if value == nil or pointsval == value then
@@ -73,5 +74,3 @@ function Pointset:get_pos_list(value)
 	end
 	return outlist
 end
-			
-	
\ No newline at end of file
diff --git a/doc.lua b/doc.lua
index 257968a..d7857bf 100644
--- a/doc.lua
+++ b/doc.lua
@@ -14,7 +14,7 @@ local battery_ratio = (10000/digtron.config.power_ratio) / coal_fuel
 
 -- internationalization boilerplate
 local MP = minetest.get_modpath(minetest.get_current_modname())
-local S, NS = dofile(MP.."/intllib.lua")
+local S = dofile(MP.."/intllib.lua")
 
 local pipeworks_enabled = minetest.get_modpath("pipeworks") ~= nil
 local hoppers_enabled = minetest.get_modpath("hopper") and hopper ~= nil and hopper.add_container ~= nil
@@ -102,7 +102,7 @@ if pipeworks_enabled then
 	.."\n\n"..
 	S("Fuel modules are compatible with Pipeworks blocks. When a Digtron moves one of the inventory modules adjacent to a pipe it will automatically hook up to it, and disconnect again when it moves on.")
 end
-	
+
 
 digtron.doc.combined_storage_longdesc = S("Stores fuel for a Digtron and also has an inventory for building materials")
 digtron.doc.combined_storage_usagehelp = S("For smaller jobs the two dedicated modules may simply be too much of a good thing, wasting precious Digtron space to give unneeded capacity. The combined storage module is the best of both worlds, splitting its internal space between building material inventory and fuel storage. It has 3/4 building material capacity and 1/4 fuel storage capacity.") .. "\n\n" .. standard_fuel_doc
diff --git a/entities.lua b/entities.lua
index d203bd9..13d6bba 100644
--- a/entities.lua
+++ b/entities.lua
@@ -7,19 +7,19 @@ minetest.register_entity("digtron:marker", {
 		physical = false,
 	},
 
-	on_activate = function(self, staticdata)
-		minetest.after(5.0, 
-			function(self) 
+	on_activate = function(self)
+		minetest.after(5.0,
+			function()
 				self.object:remove()
 			end,
 			self)
 	end,
-	
-	on_rightclick=function(self, clicker)
+
+	on_rightclick=function(self)
 		self.object:remove()
 	end,
-	
-	on_punch = function(self, hitter)
+
+	on_punch = function(self)
 		self.object:remove()
 	end,
 })
@@ -28,24 +28,31 @@ minetest.register_entity("digtron:marker_vertical", {
 	initial_properties = {
 		visual = "cube",
 		visual_size = {x=1.05, y=1.05},
-		textures = {"digtron_marker.png","digtron_marker.png","digtron_marker_side.png^[transformR90","digtron_marker_side.png^[transformR90","digtron_marker_side.png^[transformR90","digtron_marker_side.png^[transformR90"},
+		textures = {
+			"digtron_marker.png",
+			"digtron_marker.png",
+			"digtron_marker_side.png^[transformR90",
+			"digtron_marker_side.png^[transformR90",
+			"digtron_marker_side.png^[transformR90",
+			"digtron_marker_side.png^[transformR90"
+		},
 		collisionbox = {-0.525, -0.525, -0.525, 0.525, 0.525, 0.525},
 		physical = false,
 	},
 
-	on_activate = function(self, staticdata)
-		minetest.after(5.0, 
-			function(self) 
+	on_activate = function(self)
+		minetest.after(5.0,
+			function()
 				self.object:remove()
 			end,
 			self)
 	end,
-	
-	on_rightclick=function(self, clicker)
+
+	on_rightclick=function(self)
 		self.object:remove()
 	end,
-	
-	on_punch = function(self, hitter)
+
+	on_punch = function(self)
 		self.object:remove()
 	end,
 })
@@ -59,19 +66,19 @@ minetest.register_entity("digtron:marker_crate_good", {
 		physical = false,
 	},
 
-	on_activate = function(self, staticdata)
-		minetest.after(digtron.config.marker_crate_good_duration, 
-			function(self) 
+	on_activate = function(self)
+		minetest.after(digtron.config.marker_crate_good_duration,
+			function()
 				self.object:remove()
 			end,
 			self)
 	end,
-	
-	on_rightclick=function(self, clicker)
+
+	on_rightclick=function(self)
 		self.object:remove()
 	end,
-	
-	on_punch = function(self, hitter)
+
+	on_punch = function(self)
 		self.object:remove()
 	end,
 })
@@ -85,19 +92,19 @@ minetest.register_entity("digtron:marker_crate_bad", {
 		physical = false,
 	},
 
-	on_activate = function(self, staticdata)
-		minetest.after(digtron.config.marker_crate_bad_duration, 
-			function(self) 
+	on_activate = function(self)
+		minetest.after(digtron.config.marker_crate_bad_duration,
+			function()
 				self.object:remove()
 			end,
 			self)
 	end,
-	
-	on_rightclick=function(self, clicker)
+
+	on_rightclick=function(self)
 		self.object:remove()
 	end,
-	
-	on_punch = function(self, hitter)
+
+	on_punch = function(self)
 		self.object:remove()
 	end,
 })
@@ -114,7 +121,7 @@ minetest.register_entity("digtron:builder_item", {
 		textures = {""},
 		automatic_rotate = math.pi * 0.25,
 	},
-	
+
 	on_activate = function(self, staticdata)
 		local props = self.object:get_properties()
 		if staticdata ~= nil and staticdata ~= "" then
@@ -133,9 +140,9 @@ minetest.register_entity("digtron:builder_item", {
 			digtron.create_builder_item = nil
 		else
 			self.object:remove()
-		end		
+		end
 	end,
-	
+
 	get_staticdata = function(self)
 		local props = self.object:get_properties()
 		if props ~= nil and props.textures ~= nil and props.textures[1] ~= nil then
diff --git a/init.lua b/init.lua
index 82de725..f52e572 100644
--- a/init.lua
+++ b/init.lua
@@ -33,7 +33,7 @@ digtron.builder_on_place_items = {
 digtron.builder_on_place_prefixes = {
 	["farming:"] = true,
 	["farming_plus:"] = true,
-	["crops:"] = true, 
+	["crops:"] = true,
 }
 
 -- Finally, items belonging to group "digtron_on_place" will have their on_place methods called.
@@ -42,7 +42,8 @@ local digtron_modpath = minetest.get_modpath( "digtron" )
 
 dofile( digtron_modpath .. "/class_fakeplayer.lua")
 
-digtron.fake_player = DigtronFakePlayer.create({x=0,y=0,z=0}, "fake_player") -- since we only need one fake player at a time and it doesn't retain useful state, create a global one and just update it as needed.
+-- since we only need one fake player at a time and it doesn't retain useful state, create a global one and just update it as needed.
+digtron.fake_player = digtron.DigtronFakePlayer.create({x=0,y=0,z=0}, "fake_player")
 
 dofile( digtron_modpath .. "/config.lua" )
 dofile( digtron_modpath .. "/util.lua" )
diff --git a/nodes/node_axle.lua b/nodes/node_axle.lua
index 1ae9ecc..d43bd60 100644
--- a/nodes/node_axle.lua
+++ b/nodes/node_axle.lua
@@ -1,6 +1,6 @@
 -- internationalization boilerplate
 local MP = minetest.get_modpath(minetest.get_current_modname())
-local S, NS = dofile(MP.."/intllib.lua")
+local S = dofile(MP.."/intllib.lua")
 
 minetest.register_node("digtron:axle", {
 	description = S("Digtron Rotation Axle"),
@@ -21,7 +21,7 @@ minetest.register_node("digtron:axle", {
 		"digtron_plate.png^digtron_axel_side.png",
 		"digtron_plate.png^digtron_axel_side.png",
 	},
-	
+
 	drawtype = "nodebox",
 	node_box = {
 		type = "fixed",
@@ -37,10 +37,10 @@ minetest.register_node("digtron:axle", {
 	},
 
 
-	
-	on_rightclick = function(pos, node, clicker, itemstack, pointed_thing)
+
+	on_rightclick = function(pos, node, clicker)
 		local meta = minetest.get_meta(pos)
-	
+
 		-- new delay code without nodetimer (lost on crating)
 		local now = minetest.get_gametime()
 		local last_time = tonumber(meta:get_string("last_time")) or 0
@@ -54,7 +54,7 @@ minetest.register_node("digtron:axle", {
 			return
 		end
 
-		local image = DigtronLayout.create(pos, clicker)
+		local image = digtron.DigtronLayout.create(pos, clicker)
 		if image:rotate_layout_image(node.param2) == false then
 			-- This should be impossible, but if self-validation fails abort.
 			return
@@ -76,8 +76,8 @@ minetest.register_node("digtron:axle", {
 			meta:set_string("infotext", S("Digtron is obstructed."))
 		end
 	end,
-	
-	on_timer = function(pos, elapsed)
+
+	on_timer = function(pos)
 		minetest.get_meta(pos):set_string("waiting", nil)
 	end,
 })
\ No newline at end of file
diff --git a/nodes/node_battery_holder.lua b/nodes/node_battery_holder.lua
index 456f9cc..4582a35 100644
--- a/nodes/node_battery_holder.lua
+++ b/nodes/node_battery_holder.lua
@@ -1,6 +1,6 @@
 -- internationalization boilerplate
 local MP = minetest.get_modpath(minetest.get_current_modname())
-local S, NS = dofile(MP.."/intllib.lua")
+local S = dofile(MP.."/intllib.lua")
 
 
 -- Battery storage. Controller node draws electrical power from here.
@@ -18,7 +18,7 @@ local battery_holder_formspec_string = "size[8,9.3]" ..
 	"listring[current_player;main]" ..
 	default.get_hotbar_bg(0,5.15)
 
-local battery_holder_formspec = function(pos, meta)
+local battery_holder_formspec = function()
 	return battery_holder_formspec_string
 end
 
@@ -28,7 +28,7 @@ if not minetest.get_modpath("technic") then
 	-- leave them registered, though, in case technic is being removed from an existing server.
 	holder_groups.not_in_creative_inventory = 1
 end
-	
+
 minetest.register_node("digtron:battery_holder", {
 	description = S("Digtron Battery Holder"),
 	_doc_items_longdesc = digtron.doc.battery_holder_longdesc,
@@ -62,55 +62,55 @@ minetest.register_node("digtron:battery_holder", {
 		local inv = meta:get_inventory()
 		inv:set_size("batteries", 8*4)
 	end,
-	
+
 	-- Allow all items with energy storage to be placed in the inventory
-	allow_metadata_inventory_put = function(pos, listname, index, stack, player)
+	allow_metadata_inventory_put = function(_, listname, _, stack)
 		if listname == "batteries" then
 			local node_name = stack:get_name()
-                                                 
+
 			-- Allow all items with energy storage from technic mod
-			if technic.power_tools[node_name] ~= nil then                            
+			if technic.power_tools[node_name] ~= nil then
 				local meta = stack:get_metadata()
 				local md = minetest.deserialize(meta)
 				-- And specifically if they hold any charge
 				-- Disregard empty batteries, the player should know better
 				if md and md.charge > 0 then
-					return stack:get_count()    
+					return stack:get_count()
 				else
 					return 0
 				end
-                                                 
+
 			else
 				return 0
 			end
 		end
 		return 0
 	end,
-                                                  
-                                                 
-	can_dig = function(pos,player)
+
+
+	can_dig = function(pos)
 		local meta = minetest.get_meta(pos)
 		local inv = meta:get_inventory()
 		return inv:is_empty("batteries")
 	end,
-		
+
 	-- Pipeworks compatibility
 	-- Because who wouldn't send batteries through pipes if he could?
 	-----------------------------------------------------------------
 
 	tube = (function() if minetest.get_modpath("pipeworks") then return {
-		insert_object = function(pos, node, stack, direction)
+		insert_object = function(pos, _, stack)
 			local meta = minetest.get_meta(pos)
 			local inv = meta:get_inventory()
 			return inv:add_item("batteries", stack)
 		end,
-		can_insert = function(pos, node, stack, direction)
+		can_insert = function(pos, _, stack)
 			local meta = stack:get_metadata()
 			local md = minetest.deserialize(meta)
 			-- And specifically if they hold any charge
 			-- Disregard empty batteries, the player should know better
 			if md and md.charge > 0 then
-				local meta = minetest.get_meta(pos)
+				meta = minetest.get_meta(pos)
 				local inv = meta:get_inventory()
 				return inv:room_for_item("batteries", stack)
 			end
@@ -119,7 +119,7 @@ minetest.register_node("digtron:battery_holder", {
 		input_inventory = "batteries",
 		connect_sides = {left = 1, right = 1, back = 1, front = 1, bottom = 1, top = 1}
 	} end end)(),
-	
+
 	after_place_node = (function() if minetest.get_modpath("pipeworks") then return pipeworks.after_place end end)(),
 	after_dig_node = (function() if minetest.get_modpath("pipeworks")then return pipeworks.after_dig end end)()
 })
diff --git a/nodes/node_builders.lua b/nodes/node_builders.lua
index 4d17667..aacc40c 100644
--- a/nodes/node_builders.lua
+++ b/nodes/node_builders.lua
@@ -1,6 +1,6 @@
 -- internationalization boilerplate
 local MP = minetest.get_modpath(minetest.get_current_modname())
-local S, NS = dofile(MP.."/intllib.lua")
+local S = dofile(MP.."/intllib.lua")
 
 -- Note: builders go in group 4 and have both test_build and execute_build methods.
 
@@ -19,15 +19,18 @@ local builder_formspec_string =
 	"list[current_name;main;".. tostring(displace_due_to_help_button/2) ..",0;1,1;]" ..
 	"label[" .. tostring(displace_due_to_help_button/2).. ",0.8;" .. S("Block to build") .. "]" ..
 	"field[" .. tostring(displace_due_to_help_button + 1.3) ..",0.8;1,0.1;extrusion;" .. S("Extrusion") .. ";${extrusion}]" ..
-	"tooltip[extrusion;" .. S("Builder will extrude this many blocks in the direction it is facing.\nCan be set from 1 to @1.\nNote that Digtron won't build into unloaded map regions.", digtron.config.maximum_extrusion) .. "]" ..
+	"tooltip[extrusion;" .. S("Builder will extrude this many blocks in the direction it is facing.\nCan be set from 1 to @1.\nNote that Digtron won't build into unloaded map regions.",
+		digtron.config.maximum_extrusion) .. "]" ..
 	"field[" .. tostring(displace_due_to_help_button + 2.3) ..",0.8;1,0.1;period;" .. S("Periodicity") .. ";${period}]" ..
 	"tooltip[period;" .. S("Builder will build once every n steps.\nThese steps are globally aligned, so all builders with the\nsame period and offset will build on the same location.") .. "]" ..
 	"field[" .. tostring(displace_due_to_help_button + 3.3) ..",0.8;1,0.1;offset;" .. S("Offset") .. ";${offset}]" ..
-	"tooltip[offset;" .. S("Offsets the start of periodicity counting by this amount.\nFor example, a builder with period 2 and offset 0 builds\nevery even-numbered block and one with period 2 and\noffset 1 builds every odd-numbered block.") .. "]" ..
+	"tooltip[offset;" .. S("Offsets the start of periodicity counting by this amount.\nFor example, a builder with period 2 and offset 0 builds\nevery even-numbered block and one with period 2 and\n" ..
+		"offset 1 builds every odd-numbered block.") .. "]" ..
 	"button_exit[" .. tostring(displace_due_to_help_button + 4.0) ..",0.5;1,0.1;set;" .. S("Save &\nShow") .. "]" ..
 	"tooltip[set;" .. S("Saves settings") .. "]" ..
 	"field[" .. tostring(displace_due_to_help_button + 5.3) .. ",0.8;1,0.1;build_facing;" .. S("Facing") .. ";${build_facing}]" ..
-	"tooltip[build_facing;" .. S("Value from 0-23. Not all block types make use of this.\nUse the 'Read & Save' button to copy the facing of the block\ncurrently in the builder output location.") .. "]" ..
+	"tooltip[build_facing;" .. S("Value from 0-23. Not all block types make use of this.\nUse the 'Read & Save' button to copy the facing of the block\n" ..
+		"currently in the builder output location.") .. "]" ..
 	"button_exit[" .. tostring(displace_due_to_help_button + 6.0) ..",0.5;1,0.1;read;" .. S("Read &\nSave") .. "]" ..
 	"tooltip[read;" .. S("Reads the facing of the block currently in the build location,\nthen saves all settings.") .. "]" ..
 	"list[current_player;main;0,1.3;8,1;]" ..
@@ -41,9 +44,8 @@ if minetest.get_modpath("doc") then
 		"button_exit[7.0,0.5;1,0.1;help;" .. S("Help") .. "]" ..
 		"tooltip[help;" .. S("Show documentation about this block") .. "]"
 end
-	
+
 local builder_formspec = function(pos, meta)
-	local nodemeta = "nodemeta:"..pos.x .. "," .. pos.y .. "," ..pos.z
 	return builder_formspec_string
 		:gsub("${extrusion}", meta:get_int("extrusion"), 1)
 		:gsub("${period}", meta:get_int("period"), 1)
@@ -52,7 +54,7 @@ local builder_formspec = function(pos, meta)
 		:gsub("current_name", "nodemeta:"..pos.x .. "," .. pos.y .. "," ..pos.z, 2)
 end
 
-local builder_on_rightclick = function(pos, node, clicker, itemstack, pointed_thing)
+local builder_on_rightclick = function(pos, _, clicker, itemstack, pointed_thing)
 	local item_def = itemstack:get_definition()
 	if item_def.type == "node" and minetest.get_item_group(itemstack:get_name(), "digtron") > 0 then
 		local returnstack, success = minetest.item_place_node(itemstack, clicker, pointed_thing)
@@ -61,7 +63,7 @@ local builder_on_rightclick = function(pos, node, clicker, itemstack, pointed_th
 		end
 		return returnstack, success
 	end
-	local meta = minetest.get_meta(pos)	
+	local meta = minetest.get_meta(pos)
 	minetest.show_formspec(clicker:get_player_name(),
 		"digtron:builder"..minetest.pos_to_string(pos),
 		builder_formspec(pos, meta))
@@ -73,13 +75,13 @@ minetest.register_on_player_receive_fields(function(sender, formname, fields)
 		return
 	end
 	local pos = minetest.string_to_pos(formname:sub(16, -1))
-	
+
 	local meta = minetest.get_meta(pos)
 	local period = tonumber(fields.period)
 	local offset = tonumber(fields.offset)
 	local build_facing = tonumber(fields.build_facing)
 	local extrusion = tonumber(fields.extrusion)
-	
+
 	if period and period > 0 then
 		meta:set_int("period", math.floor(tonumber(fields.period)))
 	else
@@ -104,74 +106,70 @@ minetest.register_on_player_receive_fields(function(sender, formname, fields)
 	end
 	if extrusion and extrusion > 0 and extrusion <= digtron.config.maximum_extrusion then
 		meta:set_int("extrusion", math.floor(tonumber(fields.extrusion)))
-	else
-		extrusion = meta:get_int("extrusion")
 	end
-	
+
 	local nodename = minetest.get_node_or_nil(pos).name
-		
+
 	-- Master builder: bulk operations on all builders, layout cycling
 	if nodename == "digtron:master_builder" then
-	
+
 		if fields.set then
 			-- copy current settings to all builders
-			local layout = DigtronLayout.create(pos, sender)
-			
+			local layout = digtron.DigtronLayout.create(pos, sender)
+
 			if layout.builders ~= nil then
-				
+
 				local inv = meta:get_inventory()
 				local target_item = inv:get_stack("main",1)
 				local target_item_name = target_item:get_name()
-				
-				if target_item_name ~= "air" and minetest.get_item_group(target_item_name, "digtron") == 0 then
-				
-					for k, location in pairs(layout.builders) do
 
-						local target = minetest.get_node(location.pos)
+				if target_item_name ~= "air" and minetest.get_item_group(target_item_name, "digtron") == 0 then
+
+					for _, location in pairs(layout.builders) do
+
 						local target_meta = minetest.get_meta(location.pos)
 						target_meta:set_int("period", meta:get_int("period"))
 						target_meta:set_int("offset", meta:get_int("offset"))
 						target_meta:set_int("build_facing", meta:get_int("build_facing"))
 						target_meta:set_int("extrusion", meta:get_int("extrusion"))
-					
+
 						local target_inv = target_meta:get_inventory()
 						target_inv:set_stack("main", 1, target_item_name)
-						
+
 						digtron.update_builder_item(location.pos)
 					end
 				end
 			end
-			
+
 		elseif fields.read then
 
 			-- make all builders perform read&save
-			local layout = DigtronLayout.create(pos, sender)
-		
+			local layout = digtron.DigtronLayout.create(pos, sender)
+
 			if layout.builders ~= nil then
-				for k, location in pairs(layout.builders) do
-				
-					local target = minetest.get_node(location.pos)
+				for _, location in pairs(layout.builders) do
+
 					local facing = minetest.get_node(location.pos).param2
 					local buildpos = digtron.find_new_pos(location.pos, facing)
 					local target_node = minetest.get_node(buildpos)
 					if target_node.name ~= "air" and minetest.get_item_group(target_node.name, "digtron") == 0 then
-						local meta = minetest.get_meta(location.pos)
+						meta = minetest.get_meta(location.pos)
 						local inv = meta:get_inventory()
 						local target_name = digtron.builder_read_item_substitutions[target_node.name] or target_node.name
 						inv:set_stack("main", 1, target_name)
 						meta:set_int("build_facing", target_node.param2)
 						digtron.update_builder_item(location.pos)
 					end
-					
+
 				end
 
 			end
 		end
-	
-		
+
+
 	-- regular builder: changes apply only to itself
 	else
-	
+
 		if fields.set then
 			digtron.show_offset_markers(pos, offset, period)
 
@@ -180,16 +178,16 @@ minetest.register_on_player_receive_fields(function(sender, formname, fields)
 			local buildpos = digtron.find_new_pos(pos, facing)
 			local target_node = minetest.get_node(buildpos)
 			if target_node.name ~= "air" and minetest.get_item_group(target_node.name, "digtron") == 0 then
-				local meta = minetest.get_meta(pos)
+				meta = minetest.get_meta(pos)
 				local inv = meta:get_inventory()
 				local target_name = digtron.builder_read_item_substitutions[target_node.name] or target_node.name
 				inv:set_stack("main", 1, target_name)
 				meta:set_int("build_facing", target_node.param2)
 			end
 		end
-	
+
 	end
-	
+
 	if fields.help and minetest.get_modpath("doc") then --check for mod in case someone disabled it after this digger was built
 		minetest.after(0.5, doc.show_entry, sender:get_player_name(), "nodes", "digtron:builder", true)
 	end
@@ -209,7 +207,7 @@ minetest.register_node("digtron:builder", {
 	paramtype = "light",
 	paramtype2= "facedir",
 	is_ground_content = false,
-	tiles = { 
+	tiles = {
 		"digtron_plate.png^[transformR90",
 		"digtron_plate.png^[transformR270",
 		"digtron_plate.png",
@@ -217,7 +215,7 @@ minetest.register_node("digtron:builder", {
 		"digtron_plate.png^digtron_builder.png",
 		"digtron_plate.png",
 	},
-	
+
 	drawtype = "nodebox",
 	node_box = {
 		type = "fixed",
@@ -238,88 +236,88 @@ minetest.register_node("digtron:builder", {
 			{-0.3125, -0.0625, 0.3125, 0.3125, 0.0625, 0.375}, -- frontcross_horizontal
 		}
 	},
-	
+
 	on_construct = function(pos)
         local meta = minetest.get_meta(pos)
-		meta:set_int("period", 1) 
-		meta:set_int("offset", 0) 
+		meta:set_int("period", 1)
+		meta:set_int("offset", 0)
 		meta:set_int("build_facing", 0)
 		meta:set_int("extrusion", 1)
-				
+
 		local inv = meta:get_inventory()
 		inv:set_size("main", 1)
     end,
-	
+
 	on_rightclick = builder_on_rightclick,
-	
+
 	on_destruct = function(pos)
 		digtron.remove_builder_item(pos)
 	end,
-	
+
 	after_place_node = function(pos)
 		digtron.update_builder_item(pos)
 	end,
 
-	allow_metadata_inventory_put = function(pos, listname, index, stack, player)
+	allow_metadata_inventory_put = function(pos, listname, index, stack)
 		local stack_name = stack:get_name()
-	
+
 		if minetest.get_item_group(stack_name, "digtron") ~= 0 then
 			return 0 -- don't allow builders to be set to build Digtron nodes, they'll just clog the output.
-		end	
-		
+		end
+
 		local stack_def = minetest.registered_nodes[stack_name]
 		if not stack_def and not digtron.whitelisted_on_place(stack_name) then
 			return 0 -- don't allow craft items unless their on_place is whitelisted.
 		end
-		
+
 		node_inventory_table.pos = pos
 		local inv = minetest.get_inventory(node_inventory_table)
 		inv:set_stack(listname, index, stack:take_item(1))
-		
+
 		-- If we're adding a wallmounted item and the build facing is greater than 5, reset it to 0
 		local meta = minetest.get_meta(pos)
 		if stack_def ~= nil and stack_def.paramtype2 == "wallmounted" and tonumber(meta:get_int("build_facing")) > 5 then
 			meta:set_int("build_facing", 0)
 		end
-		
+
 		return 0
 	end,
-	
-	allow_metadata_inventory_take = function(pos, listname, index, stack, player)
+
+	allow_metadata_inventory_take = function(pos, listname, index)
 		node_inventory_table.pos = pos
 		local inv = minetest.get_inventory(node_inventory_table)
 		inv:set_stack(listname, index, ItemStack(""))
 		return 0
 	end,
-	
+
 	-- "builder at pos, imagine that you're in test_pos. If you're willing and able to build from there, take the item you need from inventory.
 	-- return the item you took and the inventory location you took it from so it can be put back after all the other builders have been tested.
 	-- If you couldn't get the item from inventory, return an error code so we can abort the cycle.
 	-- If you're not supposed to build at all, or the location is obstructed, return 0 to let us know you're okay and we shouldn't abort."
-	
+
 	--return code and accompanying value:
 	-- 0, {}								-- not supposed to build, no error
 	-- 1, {{itemstack, source inventory pos}, ...} -- can build, took items from inventory
 	-- 2, {{itemstack, source inventory pos}, ...}, itemstack	-- was supposed to build, but couldn't get the item from inventory
 	-- 3, {}								-- builder configuration error
-	test_build = function(pos, test_pos, inventory_positions, protected_nodes, nodes_dug, controlling_coordinate, controller_pos)
+	test_build = function(pos, test_pos, inventory_positions, protected_nodes, nodes_dug, controlling_coordinate)
 		local meta = minetest.get_meta(pos)
 		local facing = minetest.get_node(pos).param2
 		local buildpos = digtron.find_new_pos(test_pos, facing)
-		
+
 		if (buildpos[controlling_coordinate] + meta:get_int("offset")) % meta:get_int("period") ~= 0 then
 			--It's not the builder's turn to build right now.
 			return 0, {}
 		end
-		
+
 		local extrusion_count = 0
 		local extrusion_target = meta:get_int("extrusion")
 		if extrusion_target == nil or extrusion_target < 1 or extrusion_target > 100 then
 			extrusion_target = 1 -- failsafe
 		end
-		
+
 		local return_items = {}
-		
+
 		node_inventory_table.pos = pos
 		local inv = minetest.get_inventory(node_inventory_table)
 		local item_stack = inv:get_stack("main", 1)
@@ -327,20 +325,20 @@ minetest.register_node("digtron:builder", {
 		if item_stack:is_empty() then
 			return 3, {} -- error code for "this builder's item slot is unset"
 		end
-		
+
 		while extrusion_count < extrusion_target do
 			if not digtron.can_move_to(buildpos, protected_nodes, nodes_dug) then
 				--using "can_move_to" instead of "can_build_to" test case in case the builder is pointed "backward", and will thus
 				--be building into the space that it's currently in and will be vacating after moving, or in case the builder is aimed
 				--sideways and a fellow digtron node was ahead of it (will also be moving out of the way).
-				
+
 				--If the player has built his digtron stupid (eg has another digtron node in the place the builder wants to build) this
 				--assumption is wrong, but I can't hold the player's hand through *every* possible bad design decision. Worst case,
 				--the digtron will think its inventory can't handle the next build step and abort the build when it actually could have
 				--managed one more cycle. That's not a bad outcome for a digtron array that was built stupidly to begin with.
 				return 1, return_items
 			end
-			
+
 			local source_location = digtron.take_from_inventory(item_stack:get_name(), inventory_positions)
 			if source_location ~= nil then
 				table.insert(return_items, {item=item_stack, location=source_location})
@@ -350,34 +348,34 @@ minetest.register_node("digtron:builder", {
 			extrusion_count = extrusion_count + 1
 			buildpos = digtron.find_new_pos(buildpos, facing)
 		end
-		
+
 		return 1, return_items
 	end,
-	
+
 	execute_build = function(pos, player, inventory_positions, protected_nodes, nodes_dug, controlling_coordinate, controller_pos)
 		local meta = minetest.get_meta(pos)
 		local build_facing = tonumber(meta:get_int("build_facing"))
 		local facing = minetest.get_node(pos).param2
 		local buildpos = digtron.find_new_pos(pos, facing)
-		
+
 		if (buildpos[controlling_coordinate] + meta:get_int("offset")) % meta:get_int("period") ~= 0 then
 			return 0
 		end
-		
+
 		local extrusion_count = 0
 		local extrusion_target = meta:get_int("extrusion")
 		if extrusion_target == nil or extrusion_target < 1 or extrusion_target > 100 then
 			extrusion_target = 1 -- failsafe
 		end
 		local built_count = 0
-		
+
 		node_inventory_table.pos = pos
 		local inv = minetest.get_inventory(node_inventory_table)
 		local item_stack = inv:get_stack("main", 1)
 		if item_stack:is_empty() then
 			return built_count
 		end
-		
+
 		while extrusion_count < extrusion_target do
 			if not digtron.can_build_to(buildpos, protected_nodes, nodes_dug) then
 				return built_count
@@ -386,24 +384,26 @@ minetest.register_node("digtron:builder", {
 			local oldnode = minetest.get_node(buildpos)
 
 			if not digtron.config.uses_resources then
-				local returned_stack, success = digtron.item_place_node(item_stack, player, buildpos, build_facing)
+				local _, success = digtron.item_place_node(item_stack, player, buildpos, build_facing)
 				if success == true then
-					minetest.log("action", string.format("%s uses Digtron to build %s at (%d, %d, %d), displacing %s", player:get_player_name(), item_stack:get_name(), buildpos.x, buildpos.y, buildpos.z, oldnode.name))
+					minetest.log("action",
+						string.format("%s uses Digtron to build %s at (%d, %d, %d), displacing %s", player:get_player_name(), item_stack:get_name(), buildpos.x, buildpos.y, buildpos.z, oldnode.name))
 					nodes_dug:set(buildpos.x, buildpos.y, buildpos.z, false)
 					built_count = built_count + 1
 				else
 					return built_count
 				end
 			end
-		
+
 			local sourcepos = digtron.take_from_inventory(item_stack:get_name(), inventory_positions)
 			if sourcepos == nil then
 				-- item not in inventory! Need to sound the angry buzzer to let the player know, so return a negative number.
 				return (built_count + 1) * -1
 			end
-			local returned_stack, success = digtron.item_place_node(ItemStack(item_stack), player, buildpos, build_facing)
+			local _, success = digtron.item_place_node(ItemStack(item_stack), player, buildpos, build_facing)
 			if success == true then
-				minetest.log("action", string.format("%s uses Digtron to build %s at (%d, %d, %d), displacing %s", player:get_player_name(), item_stack:get_name(), buildpos.x, buildpos.y, buildpos.z, oldnode.name))
+				minetest.log("action",
+					string.format("%s uses Digtron to build %s at (%d, %d, %d), displacing %s", player:get_player_name(), item_stack:get_name(), buildpos.x, buildpos.y, buildpos.z, oldnode.name))
 				--flag this node as *not* to be dug.
 				nodes_dug:set(buildpos.x, buildpos.y, buildpos.z, false)
 				digtron.award_item_built(item_stack:get_name(), player)
@@ -423,7 +423,7 @@ minetest.register_node("digtron:builder", {
 })
 
 -- Master builder node
--- Does not build anything, but can set all other builders to a certain item 
+-- Does not build anything, but can set all other builders to a certain item
 -- OR make all other builders perform read & save operation.
 -- First function is handy e.g. for farming combines, the second is handy for templates.
 -- The formspec is reused, but the buttons are behaving differently from regular builder:
@@ -448,7 +448,7 @@ minetest.register_node("digtron:master_builder", {
 		"digtron_plate.png^digtron_master_builder.png^[colorize:" .. digtron.auto_controller_colorize,
 		"digtron_plate.png^digtron_master_builder.png^[colorize:" .. digtron.auto_controller_colorize,
 	},
-	
+
 	drawtype = "nodebox",
 	node_box = {
 		type = "fixed",
@@ -467,59 +467,59 @@ minetest.register_node("digtron:master_builder", {
 			{-0.3125, -0.5, -0.5, 0.3125, -0.3125, -0.3125},
 		}
 	},
-	
+
 	on_construct = function(pos)
         local meta = minetest.get_meta(pos)
-		meta:set_int("period", 1) 
-		meta:set_int("offset", 0) 
+		meta:set_int("period", 1)
+		meta:set_int("offset", 0)
 		meta:set_int("build_facing", 0)
 		meta:set_int("extrusion", 1)
-				
+
 		local inv = meta:get_inventory()
 		inv:set_size("main", 1)
 	end,
-	
+
 	on_rightclick = builder_on_rightclick,
-	
+
 	on_destruct = function(pos)
 		digtron.remove_builder_item(pos)
 	end,
-	
+
 	after_place_node = function(pos)
 		digtron.update_builder_item(pos)
 	end,
 
-	allow_metadata_inventory_put = function(pos, listname, index, stack, player)
+	allow_metadata_inventory_put = function(pos, listname, index, stack)
 		local stack_name = stack:get_name()
-	
+
 		if minetest.get_item_group(stack_name, "digtron") ~= 0 then
 			return 0 -- don't allow builders to be set to build Digtron nodes, they'll just clog the output.
-		end	
-		
+		end
+
 		local stack_def = minetest.registered_nodes[stack_name]
 		if not stack_def and not digtron.whitelisted_on_place(stack_name) then
 			return 0 -- don't allow craft items unless their on_place is whitelisted.
 		end
-		
+
 		node_inventory_table.pos = pos
 		local inv = minetest.get_inventory(node_inventory_table)
 		inv:set_stack(listname, index, stack:take_item(1))
-		
+
 		-- If we're adding a wallmounted item and the build facing is greater than 5, reset it to 0
 		local meta = minetest.get_meta(pos)
 		if stack_def ~= nil and stack_def.paramtype2 == "wallmounted" and tonumber(meta:get_int("build_facing")) > 5 then
 			meta:set_int("build_facing", 0)
 		end
-		
+
 		return 0
 	end,
-	
-	allow_metadata_inventory_take = function(pos, listname, index, stack, player)
+
+	allow_metadata_inventory_take = function(pos, listname, index)
 		node_inventory_table.pos = pos
 		local inv = minetest.get_inventory(node_inventory_table)
 		inv:set_stack(listname, index, ItemStack(""))
 		return 0
 	end,
-	
+
 
 })
diff --git a/nodes/node_controllers.lua b/nodes/node_controllers.lua
index 8e20919..f7503a7 100644
--- a/nodes/node_controllers.lua
+++ b/nodes/node_controllers.lua
@@ -1,6 +1,6 @@
 -- internationalization boilerplate
 local MP = minetest.get_modpath(minetest.get_current_modname())
-local S, NS = dofile(MP.."/intllib.lua")
+local S = dofile(MP.."/intllib.lua")
 
 local controller_nodebox ={
 	{-0.3125, -0.3125, -0.3125, 0.3125, 0.3125, 0.3125}, -- Core
@@ -39,20 +39,20 @@ minetest.register_node("digtron:controller", {
 		"digtron_plate.png",
 		"digtron_plate.png^digtron_control.png",
 	},
-	
+
 	drawtype = "nodebox",
 	node_box = {
 		type = "fixed",
 		fixed = controller_nodebox,
 	},
-	
+
 	on_construct = function(pos)
         local meta = minetest.get_meta(pos)
 		meta:set_float("fuel_burning", 0.0)
 		meta:set_string("infotext", S("Heat remaining in controller furnace: @1", 0))
 	end,
-	
-	on_rightclick = function(pos, node, clicker, itemstack, pointed_thing)
+
+	on_rightclick = function(pos, _, clicker)
 		local meta = minetest.get_meta(pos)
 
 		-- new delay code without nodetimer (lost on crating)
@@ -62,28 +62,28 @@ minetest.register_node("digtron:controller", {
 		-- if meta:get_string("waiting") == "true" then
 		if last_time + digtron.config.cycle_time > now then
 		   -- Been too soon since last time the digtron did a cycle.
-		   
+
 		   -- added for clarity
 		   meta:set_string("infotext", S("repetition delay"))
-		   
+
 		   return
 		end
-	
-		local newpos, status, return_code = digtron.execute_dig_cycle(pos, clicker)
-		
+
+		local newpos, status = digtron.execute_dig_cycle(pos, clicker)
+
 		meta = minetest.get_meta(newpos)
 		if status ~= nil then
 			meta:set_string("infotext", status)
 		end
-		
+
 		-- Start the delay before digtron can run again.
 		minetest.get_meta(newpos):set_string("waiting", "true")
 		-- minetest.get_node_timer(newpos):start(digtron.config.cycle_time)
 		-- new delay code
 		meta:set_string("last_time",tostring(minetest.get_gametime()))
 	end,
-	
-	on_timer = function(pos, elapsed)
+
+	on_timer = function(pos)
 		minetest.get_meta(pos):set_string("waiting", nil)
 	end,
 })
@@ -97,15 +97,18 @@ local auto_formspec = "size[8,6.2]" ..
 	default.gui_slots ..
 	"container[2.0,0]" ..
 	"field[0.0,0.8;1,0.1;cycles;" .. S("Cycles").. ";${cycles}]" ..
-	"tooltip[cycles;" .. S("When triggered, this controller will try to run for the given number of cycles.\nThe cycle count will decrement as it runs, so if it gets halted by a problem\nyou can fix the problem and restart.").. "]" ..
+	"tooltip[cycles;" .. S("When triggered, this controller will try to run for the given number of cycles.\nThe cycle count will decrement as it runs, so if it gets halted by a problem\n" ..
+		"you can fix the problem and restart.").. "]" ..
 	"button_exit[0.7,0.5;1,0.1;set;" .. S("Set").. "]" ..
 	"tooltip[set;" .. S("Saves the cycle setting without starting the controller running").. "]" ..
 	"button_exit[1.7,0.5;1,0.1;execute;" .. S("Set &\nExecute").. "]" ..
 	"tooltip[execute;" .. S("Begins executing the given number of cycles").. "]" ..
 	"field[0.0,2.0;1,0.1;slope;" .. S("Slope").. ";${slope}]" ..
-	"tooltip[slope;" .. S("For diagonal digging. After moving forward this number of nodes the auto controller\nwill add an additional cycle moving the digtron laterally in the\ndirection of the arrows on the side of this controller.\nSet to 0 for no lateral digging.").. "]" ..
+	"tooltip[slope;" .. S("For diagonal digging. After moving forward this number of nodes the auto controller\nwill add an additional cycle moving the digtron laterally in the\n" ..
+		"direction of the arrows on the side of this controller.\nSet to 0 for no lateral digging.").. "]" ..
 	"field[1.0,2.0;1,0.1;offset;" .. S("Offset").. ";${offset}]" ..
-	"tooltip[offset;" .. S("Sets the offset of the lateral motion defined in the Slope field.\nNote: this offset is relative to the controller's location.\nThe controller will move laterally when it reaches the indicated point.").. "]" ..
+	"tooltip[offset;" .. S("Sets the offset of the lateral motion defined in the Slope field.\nNote: this offset is relative to the controller's location.\n" ..
+		"The controller will move laterally when it reaches the indicated point.").. "]" ..
 	"field[2.0,2.0;1,0.1;period;" .. S("Delay").. ";${period}]" ..
 	"tooltip[period;" .. S("Number of seconds to wait between each cycle").. "]" ..
 	"list[current_name;stop;3.0,0.7;1,1;]" ..
@@ -121,7 +124,7 @@ if minetest.get_modpath("doc") then
 	auto_formspec = auto_formspec ..
 	"button_exit[7.0,0.5;1,0.1;help;" .. S("Help") .. "]" ..
 	"tooltip[help;" .. S("Show documentation about this block").. "]"
-end	
+end
 
 local function auto_cycle(pos)
 	local node = minetest.get_node(pos)
@@ -134,11 +137,11 @@ local function auto_cycle(pos)
 
 	local cycle = meta:get_int("cycles")
 	local slope = meta:get_int("slope")
-	
+
 	if meta:get_string("lateral_done") ~= "true" and slope ~= 0 and (pos[controlling_coordinate] + meta:get_int("offset")) % slope == 0 then
 		--Do a downward dig cycle. Don't update the "cycles" count, these don't count towards that.
 		local newpos, status, return_code = digtron.execute_downward_dig_cycle(pos, player)
-		
+
 		if vector.equals(pos, newpos) then
 			status = status .. "\n" .. S("Cycles remaining: @1", cycle) .. "\n" .. S("Halted!")
 			meta:set_string("infotext", status)
@@ -174,14 +177,14 @@ local function auto_cycle(pos)
 		end
 		return
 	end
-	
+
 	meta = minetest.get_meta(newpos)
 	cycle = meta:get_int("cycles") - 1
 	meta:set_int("cycles", cycle)
 	status = status .. "\n" .. S("Cycles remaining: @1", cycle)
 	meta:set_string("infotext", status)
 	meta:set_string("lateral_done", nil)
-	
+
 	if cycle > 0 then
 		minetest.after(meta:get_int("period"), auto_cycle, newpos)
 	else
@@ -211,13 +214,13 @@ minetest.register_node("digtron:auto_controller", {
 		"digtron_plate.png^[colorize:" .. digtron.auto_controller_colorize,
 		"digtron_plate.png^digtron_control.png^[colorize:" .. digtron.auto_controller_colorize,
 	},
-	
+
 	drawtype = "nodebox",
 	node_box = {
 		type = "fixed",
 		fixed = controller_nodebox,
 	},
-	
+
 	on_construct = function(pos)
         local meta = minetest.get_meta(pos)
 		meta:set_float("fuel_burning", 0.0)
@@ -228,35 +231,35 @@ minetest.register_node("digtron:auto_controller", {
 		meta:set_int("offset", 0)
 		meta:set_int("cycles", 0)
 		meta:set_int("slope", 0)
-		
+
 		local inv = meta:get_inventory()
 		inv:set_size("stop", 1)
 	end,
 
-	allow_metadata_inventory_put = function(pos, listname, index, stack, player)
+	allow_metadata_inventory_put = function(pos, listname, index, stack)
 		if minetest.get_item_group(stack:get_name(), "digtron") ~= 0 then
 			return 0 -- pointless setting a Digtron node as a stop block
-		end	
+		end
 		node_inventory_table.pos = pos
 		local inv = minetest.get_inventory(node_inventory_table)
 		inv:set_stack(listname, index, stack:take_item(1))
 		return 0
 	end,
-	
-	allow_metadata_inventory_take = function(pos, listname, index, stack, player)
+
+	allow_metadata_inventory_take = function(pos, listname, index)
 		node_inventory_table.pos = pos
 		local inv = minetest.get_inventory(node_inventory_table)
 		inv:set_stack(listname, index, ItemStack(""))
 		return 0
 	end,
-	
-	on_receive_fields = function(pos, formname, fields, sender)
+
+	on_receive_fields = function(pos, _, fields, sender)
         local meta = minetest.get_meta(pos)
 		local offset = tonumber(fields.offset)
 		local period = tonumber(fields.period)
 		local slope = tonumber(fields.slope)
 		local cycles = tonumber(fields.cycles)
-		
+
 		if period and period > 0 then
 			meta:set_int("period", math.max(digtron.config.cycle_time, math.floor(period)))
 		end
@@ -264,11 +267,11 @@ minetest.register_node("digtron:auto_controller", {
 		if offset then
 			meta:set_int("offset", offset)
 		end
-		
+
 		if slope and slope >= 0 then
 			meta:set_int("slope", slope)
 		end
-		
+
 		if cycles and cycles >= 0 then
 			meta:set_int("cycles", math.floor(cycles))
 			if sender:is_player() and cycles > 0 then
@@ -284,7 +287,7 @@ minetest.register_node("digtron:auto_controller", {
 		if fields.set and slope and slope > 0 then
 			local node = minetest.get_node(pos)
 			local controlling_coordinate = digtron.get_controlling_coordinate(pos, node.param2)
-			
+
 			offset = offset or 0
 			local newpos = pos
 			local markerpos = {x=newpos.x, y=newpos.y, z=newpos.z}
@@ -299,14 +302,14 @@ minetest.register_node("digtron:auto_controller", {
 				markerpos[controlling_coordinate] = x_pos + slope
 				minetest.add_entity(markerpos, "digtron:marker_vertical")
 			end
-		end	
-		
+		end
+
 		if fields.help and minetest.get_modpath("doc") then --check for mod in case someone disabled it after this digger was built
 			minetest.after(0.5, doc.show_entry, sender:get_player_name(), "nodes", "digtron:auto_controller", true)
 		end
-	end,	
-	
-	on_rightclick = function(pos, node, clicker, itemstack, pointed_thing)
+	end,
+
+	on_rightclick = function(pos)
 		local meta = minetest.get_meta(pos)
 		meta:set_string("infotext", meta:get_string("infotext") .. "\n" .. S("Interrupted!"))
 		meta:set_string("waiting", "true")
@@ -338,30 +341,30 @@ minetest.register_node("digtron:pusher", {
 		"digtron_plate.png^[colorize:" .. digtron.pusher_controller_colorize,
 		"digtron_plate.png^digtron_control.png^[colorize:" .. digtron.pusher_controller_colorize,
 	},
-	
+
 	drawtype = "nodebox",
 	node_box = {
 		type = "fixed",
 		fixed = controller_nodebox,
 	},
-	
-	on_rightclick = function(pos, node, clicker, itemstack, pointed_thing)	
+
+	on_rightclick = function(pos, _, clicker)
 		local meta = minetest.get_meta(pos)
 		if meta:get_string("waiting") == "true" then
 			-- Been too soon since last time the digtron did a cycle.
 			return
 		end
 
-		local newpos, status_text, return_code = digtron.execute_move_cycle(pos, clicker)
+		local newpos, status_text = digtron.execute_move_cycle(pos, clicker)
 		meta = minetest.get_meta(newpos)
 		meta:set_string("infotext", status_text)
-		
+
 		-- Start the delay before digtron can run again.
 		minetest.get_meta(newpos):set_string("waiting", "true")
 		minetest.get_node_timer(newpos):start(digtron.config.cycle_time)
 	end,
-	
-	on_timer = function(pos, elapsed)
+
+	on_timer = function(pos)
 		minetest.get_meta(pos):set_string("waiting", nil)
 	end,
 })
diff --git a/nodes/node_crate.lua b/nodes/node_crate.lua
index d0dc7fd..e64e8f2 100644
--- a/nodes/node_crate.lua
+++ b/nodes/node_crate.lua
@@ -1,6 +1,6 @@
 -- internationalization boilerplate
 local MP = minetest.get_modpath(minetest.get_current_modname())
-local S, NS = dofile(MP.."/intllib.lua")
+local S = dofile(MP.."/intllib.lua")
 
 local modpath_awards = minetest.get_modpath("awards")
 
@@ -23,14 +23,14 @@ local player_permitted = function(pos, player)
 end
 
 local store_digtron = function(pos, clicker, loaded_node_name, protected)
-	local layout = DigtronLayout.create(pos, clicker)
+	local layout = digtron.DigtronLayout.create(pos, clicker)
 	local protection_prefix = ""
 	local protection_suffix = ""
 	if protected then
 		protection_prefix = S("Digtron Crate") .. "\n" .. S("Owned by @1", clicker:get_player_name() or "")
 		protection_suffix = S("Owned by @1", clicker:get_player_name() or "")
 	end
-	
+
 	if layout.contains_protected_node then
 		local meta = minetest.get_meta(pos)
 		minetest.sound_play("buzzer", {gain=0.5, pos=pos})
@@ -38,7 +38,7 @@ local store_digtron = function(pos, clicker, loaded_node_name, protected)
 		-- no stealing other peoples' digtrons
 		return
 	end
-	
+
 	if #layout.all == 1 then
 		local meta = minetest.get_meta(pos)
 		minetest.sound_play("buzzer", {gain=0.5, pos=pos})
@@ -47,34 +47,34 @@ local store_digtron = function(pos, clicker, loaded_node_name, protected)
 	end
 
 	digtron.award_crate(layout, clicker:get_player_name())
-	
+
 	local layout_string = layout:serialize()
-	
+
 	-- destroy everything. Note that this includes the empty crate, which will be bundled up with the layout.
 	for _, node_image in pairs(layout.all) do
 		local old_pos = node_image.pos
 		local old_node = node_image.node
 		minetest.remove_node(old_pos)
-		
+
 		if modpath_awards then
 			-- We're about to tell the awards mod that we're digging a node, but we
 			-- don't want it to count toward any actual awards. Pre-decrement.
 			local data = awards.player(clicker:get_player_name())
 			awards.increment_item_counter(data, "dig", old_node.name, -1)
 		end
-		
+
 		for _, callback in ipairs(minetest.registered_on_dignodes) do
 			-- Copy pos and node because callback can modify them
 			local pos_copy = {x=old_pos.x, y=old_pos.y, z=old_pos.z}
 			local oldnode_copy = {name=old_node.name, param1=old_node.param1, param2=old_node.param2}
 			callback(pos_copy, oldnode_copy, clicker)
-		end			
+		end
 	end
-	
+
 	-- Create the loaded crate node
 	minetest.set_node(pos, {name=loaded_node_name})
 	minetest.sound_play("machine1", {gain=1.0, pos=pos})
-	
+
 	local meta = minetest.get_meta(pos)
 	meta:set_string("crated_layout", layout_string)
 
@@ -107,12 +107,12 @@ minetest.register_node("digtron:empty_crate", {
         },
     },
 	paramtype = "light",
-	
+
 	can_dig = function(pos, player)
 		return player and not minetest.is_protected(pos, player:get_player_name())
 	end,
 
-	on_rightclick = function(pos, node, clicker, itemstack, pointed_thing)
+	on_rightclick = function(pos, _, clicker)
 		store_digtron(pos, clicker, "digtron:loaded_crate")
 	end
 })
@@ -147,7 +147,7 @@ minetest.register_node("digtron:empty_locked_crate", {
 	can_dig = function(pos,player)
 		return player and not minetest.is_protected(pos, player:get_player_name()) and player_permitted(pos, player)
 	end,
-	on_rightclick = function(pos, node, clicker, itemstack, pointed_thing)
+	on_rightclick = function(pos, _, clicker)
 		if player_permitted(pos,clicker) then
 			store_digtron(pos, clicker, "digtron:loaded_locked_crate", true)
 		end
@@ -186,7 +186,7 @@ else
 	"tooltip[unpack;" .. S("Attempts to unpack the Digtron on this location") .. "]"
 end
 
-local loaded_formspec = function(pos, meta)
+local loaded_formspec = function()
 	return loaded_formspec_string
 end
 
@@ -198,14 +198,14 @@ local loaded_on_recieve = function(pos, fields, sender, protected)
 	end
 	local title = meta:get_string("title")
 	local infotext
-	
+
 	if protected then
 		infotext = title .. "\n" .. S("Owned by @1", sender:get_player_name())
 	else
 		infotext = title
 	end
 	meta:set_string("infotext", infotext)
-	
+
 	if fields.help and minetest.get_modpath("doc") then --check for mod in case someone disabled it after this digger was built
 		minetest.after(0.5, doc.show_entry, sender:get_player_name(), "nodes", "digtron:loaded_crate", true)
 	end
@@ -213,20 +213,20 @@ local loaded_on_recieve = function(pos, fields, sender, protected)
 	if not (fields.unpack or fields.show) then
 		return
 	end
-	
+
 	local layout_string = meta:get_string("crated_layout")
-	local layout = DigtronLayout.deserialize(layout_string)
+	local layout = digtron.DigtronLayout.deserialize(layout_string)
 
 	if layout == nil then
 		meta:set_string("infotext", infotext .. "\n" .. S("Unable to read layout from crate metadata, regrettably this Digtron may be corrupted."))
-		minetest.sound_play("buzzer", {gain=0.5, pos=pos})			
+		minetest.sound_play("buzzer", {gain=0.5, pos=pos})
 		-- Something went horribly wrong
 		return
 	end
-	
+
 	local protected_node = false
 	local obstructed_node = false
-	
+
 	local pos_diff = vector.subtract(pos, layout.controller)
 	layout.controller = pos
 	for _, node_image in pairs(layout.all) do
@@ -243,23 +243,23 @@ local loaded_on_recieve = function(pos, fields, sender, protected)
 			end
 		end
 	end
-	
+
 	if not fields.unpack then
 		return
 	end
-	
+
 	if protected_node then
 		meta:set_string("infotext", infotext .. "\n" .. S("Unable to deploy Digtron due to protected blocks in target area"))
 		minetest.sound_play("buzzer", {gain=0.5, pos=pos})
 		return
 	end
-	
+
 	if obstructed_node then
 		meta:set_string("infotext", infotext .. "\n" .. S("Unable to deploy Digtron due to obstruction in target area"))
 		minetest.sound_play("buzzer", {gain=0.5, pos=pos})
 		return
 	end
-	
+
 	-- build digtron. Since the empty crate was included in the layout, that will overwrite this loaded crate and destroy it.
 	minetest.sound_play("machine2", {gain=1.0, pos=pos})
 	layout:write_layout_image(sender)
@@ -267,18 +267,18 @@ end
 
 local loaded_on_dig = function(pos, player, loaded_node_name)
 	local meta = minetest.get_meta(pos)
-	
+
 	local stack = ItemStack({name=loaded_node_name, count=1, wear=0})
 	local stack_meta = stack:get_meta()
 	stack_meta:set_string("crated_layout", meta:get_string("crated_layout"))
 	stack_meta:set_string("description", meta:get_string("title"))
 	local inv = player:get_inventory()
-	local stack = inv:add_item("main", stack)
+	stack = inv:add_item("main", stack)
 	if stack:get_count() > 0 then
 		-- prevent crash by not dropping loaded crate (see #44)
 		-- minetest.add_item(pos, stack)
 		return false
-	end		
+	end
 	-- call on_dignodes callback
 	minetest.remove_node(pos)
 end
@@ -302,7 +302,7 @@ local loaded_after_place = function(pos, itemstack)
 	local title = stack_meta:get_string("description")
 	if layout ~= "" then
 		local meta = minetest.get_meta(pos)
-			
+
 		meta:set_string("crated_layout", layout)
 		meta:set_string("title", title)
 		meta:set_string("infotext", title)
@@ -320,26 +320,26 @@ minetest.register_node("digtron:loaded_crate", {
 	sounds = default.node_sound_wood_defaults(),
 	tiles = {"digtron_plate.png^digtron_crate.png"},
 	is_ground_content = false,
-	
+
 	on_construct = function(pos)
 		local meta = minetest.get_meta(pos)
 		meta:set_string("formspec", loaded_formspec(pos, meta))
 	end,
-	
-	on_receive_fields = function(pos, formname, fields, sender)
+
+	on_receive_fields = function(pos, _, fields, sender)
 		return loaded_on_recieve(pos, fields, sender)
 	end,
 
-	on_dig = function(pos, node, player)
+	on_dig = function(pos, _, player)
 		if player and not minetest.is_protected(pos, player:get_player_name()) then
 			return loaded_on_dig(pos, player, "digtron:loaded_crate")
 		end
 	end,
-	
-	after_place_node = function(pos, placer, itemstack, pointed_thing)
+
+	after_place_node = function(pos, _, itemstack)
 		loaded_after_place(pos, itemstack)
 	end,
-	on_drop = function(a, b, c) end -- prevent dropping loaded digtrons, causing server to crash (see #44)
+	on_drop = function() end -- prevent dropping loaded digtrons, causing server to crash (see #44)
 })
 
 minetest.register_node("digtron:loaded_locked_crate", {
@@ -349,32 +349,36 @@ minetest.register_node("digtron:loaded_locked_crate", {
 	groups = {cracky = 3, oddly_breakable_by_hand=3, not_in_creative_inventory=1, digtron_protected=1},
 	stack_max = 1,
 	sounds = default.node_sound_wood_defaults(),
-	tiles = {"digtron_plate.png^digtron_crate.png","digtron_plate.png^digtron_crate.png","digtron_plate.png^digtron_crate.png^digtron_lock.png","digtron_plate.png^digtron_crate.png^digtron_lock.png","digtron_plate.png^digtron_crate.png^digtron_lock.png","digtron_plate.png^digtron_crate.png^digtron_lock.png"},
+	tiles = {
+		"digtron_plate.png^digtron_crate.png",
+		"digtron_plate.png^digtron_crate.png",
+		"digtron_plate.png^digtron_crate.png^digtron_lock.png",
+		"digtron_plate.png^digtron_crate.png^digtron_lock.png",
+		"digtron_plate.png^digtron_crate.png^digtron_lock.png",
+		"digtron_plate.png^digtron_crate.png^digtron_lock.png"
+	},
 	is_ground_content = false,
-	
+
 	on_construct = function(pos)
 		local meta = minetest.get_meta(pos)
 		meta:set_string("owner", "")
 	end,
---	can_dig = function(pos,node,player)
---		return player and not minetest.is_protected(pos, player:get_player_name()) and player_permitted(pos,player)
---	end,
-	on_dig = function(pos, node, player)
+	on_dig = function(pos, _, player)
 		if player and not minetest.is_protected(pos, player:get_player_name()) and player_permitted(pos,player) then
 			return loaded_on_dig(pos, player, "digtron:loaded_locked_crate")
 		else
 			return false
 		end
 	end,
-	
-	after_place_node = function(pos, placer, itemstack, pointed_thing)
+
+	after_place_node = function(pos, placer, itemstack)
 		local meta = minetest.get_meta(pos)
 		meta:set_string("owner", placer:get_player_name() or "")
 		loaded_after_place(pos, itemstack)
 		meta:set_string("infotext", meta:get_string("infotext") .. "\n" .. S("Owned by @1", meta:get_string("owner")))
 	end,
-	
-	on_rightclick = function(pos, node, clicker, itemstack, pointed_thing)
+
+	on_rightclick = function(pos, _, clicker)
 		if player_permitted(pos,clicker) then
 			local meta = minetest.get_meta(pos)
 			minetest.show_formspec(
@@ -383,7 +387,7 @@ minetest.register_node("digtron:loaded_locked_crate", {
 				loaded_formspec_string:gsub("${title}", meta:get_string("title"), 1))
 		end
 	end,
-	on_drop = function(a, b, c) end -- prevent dropping loaded digtrons, causing server to crash
+	on_drop = function() end -- prevent dropping loaded digtrons, causing server to crash
 })
 
 minetest.register_on_player_receive_fields(function(player, formname, fields)
diff --git a/nodes/node_diggers.lua b/nodes/node_diggers.lua
index 38ba539..85f4620 100644
--- a/nodes/node_diggers.lua
+++ b/nodes/node_diggers.lua
@@ -1,6 +1,6 @@
 -- internationalization boilerplate
 local MP = minetest.get_modpath(minetest.get_current_modname())
-local S, NS = dofile(MP.."/intllib.lua")
+local S = dofile(MP.."/intllib.lua")
 
 -- Note: diggers go in group 3 and have an execute_dig method.
 
@@ -36,7 +36,8 @@ local intermittent_formspec_string = default.gui_bg ..
 	"field[0.5,0.8;1,0.1;period;" .. S("Periodicity") .. ";${period}]" ..
 	"tooltip[period;" .. S("Digger will dig once every n steps.\nThese steps are globally aligned, all diggers with\nthe same period and offset will dig on the same location.") .. "]" ..
 	"field[1.5,0.8;1,0.1;offset;" .. S("Offset") .. ";${offset}]" ..
-	"tooltip[offset;" .. S("Offsets the start of periodicity counting by this amount.\nFor example, a digger with period 2 and offset 0 digs\nevery even-numbered block and one with period 2 and\noffset 1 digs every odd-numbered block.") .. "]" ..
+	"tooltip[offset;" .. S("Offsets the start of periodicity counting by this amount.\nFor example, a digger with period 2 and offset 0 digs\nevery even-numbered block and one with period 2 and\n" ..
+		"offset 1 digs every odd-numbered block.") .. "]" ..
 	"button_exit[2.2,0.5;1,0.1;set;" .. S("Save &\nShow") .. "]" ..
 	"tooltip[set;" .. S("Saves settings") .. "]"
 
@@ -48,7 +49,7 @@ if modpath_doc then
 		intermittent_formspec_string = "size[3.5,1]" .. intermittent_formspec_string
 	end
 
-local intermittent_formspec = function(pos, meta)
+local intermittent_formspec = function(_, meta)
 	return intermittent_formspec_string
 		:gsub("${period}", meta:get_int("period"), 1)
 		:gsub("${offset}", meta:get_int("offset"), 1)
@@ -56,11 +57,11 @@ local intermittent_formspec = function(pos, meta)
 
 local intermittent_on_construct = function(pos)
     local meta = minetest.get_meta(pos)
-	meta:set_int("period", 1) 
-	meta:set_int("offset", 0) 
+	meta:set_int("period", 1)
+	meta:set_int("offset", 0)
 end
 
-local intermittent_on_rightclick = function(pos, node, clicker, itemstack, pointed_thing)
+local intermittent_on_rightclick = function(pos, _, clicker, itemstack, pointed_thing)
 	local item_def = itemstack:get_definition()
 	if item_def.type == "node" and minetest.get_item_group(itemstack:get_name(), "digtron") > 0 then
 		local returnstack, success = minetest.item_place_node(itemstack, clicker, pointed_thing)
@@ -69,7 +70,7 @@ local intermittent_on_rightclick = function(pos, node, clicker, itemstack, point
 		end
 		return returnstack, success
 	end
-	local meta = minetest.get_meta(pos)	
+	local meta = minetest.get_meta(pos)
 	minetest.show_formspec(clicker:get_player_name(),
 		"digtron:intermittent_digger"..minetest.pos_to_string(pos),
 		intermittent_formspec(pos, meta))
@@ -111,13 +112,13 @@ minetest.register_node("digtron:digger", {
 	sounds = digtron.metal_sounds,
 	paramtype = "light",
 	paramtype2= "facedir",
-	is_ground_content = false,	
+	is_ground_content = false,
 	drawtype="nodebox",
 	node_box = {
 		type = "fixed",
 		fixed = digger_nodebox,
 	},
-	
+
 	-- Aims in the +Z direction by default
 	tiles = {
 		"digtron_plate.png^[transformR90",
@@ -137,18 +138,18 @@ minetest.register_node("digtron:digger", {
 	},
 
 	-- returns fuel_cost, item_produced
-	execute_dig = function(pos, protected_nodes, nodes_dug, controlling_coordinate, lateral_dig, player)
+	execute_dig = function(pos, protected_nodes, nodes_dug, _, _, player)
 		local facing = minetest.get_node(pos).param2
 		local digpos = digtron.find_new_pos(pos, facing)
 
 		if protected_nodes:get(digpos.x, digpos.y, digpos.z) then
 			return 0
 		end
-		
+
 		return digtron.mark_diggable(digpos, nodes_dug, player)
 	end,
-	
-	damage_creatures = function(player, pos, controlling_coordinate, items_dropped)
+
+	damage_creatures = function(player, pos, _, items_dropped)
 		local facing = minetest.get_node(pos).param2
 		digtron.damage_creatures(player, pos, digtron.find_new_pos(pos, facing), damage_hp, items_dropped)
 	end,
@@ -165,13 +166,13 @@ minetest.register_node("digtron:intermittent_digger", {
 	sounds = digtron.metal_sounds,
 	paramtype = "light",
 	paramtype2= "facedir",
-	is_ground_content = false,	
+	is_ground_content = false,
 	drawtype="nodebox",
 	node_box = {
 		type = "fixed",
 		fixed = digger_nodebox,
 	},
-	
+
 	-- Aims in the +Z direction by default
 	tiles = {
 		"digtron_plate.png^[transformR90",
@@ -189,9 +190,9 @@ minetest.register_node("digtron:intermittent_digger", {
 		},
 		"digtron_plate.png^digtron_intermittent.png^digtron_motor.png",
 	},
-	
+
 	on_construct = intermittent_on_construct,
-	
+
 	on_rightclick = intermittent_on_rightclick,
 
 	-- returns fuel_cost, item_produced (a table or nil)
@@ -206,15 +207,15 @@ minetest.register_node("digtron:intermittent_digger", {
 		if protected_nodes:get(digpos.x, digpos.y, digpos.z) then
 			return 0
 		end
-		
+
 		local meta = minetest.get_meta(pos)
 		if (digpos[controlling_coordinate] + meta:get_int("offset")) % meta:get_int("period") ~= 0 then
 			return 0
 		end
-		
+
 		return digtron.mark_diggable(digpos, nodes_dug, player)
 	end,
-	
+
 	damage_creatures = function(player, pos, controlling_coordinate, items_dropped)
 		local facing = minetest.get_node(pos).param2
 		local targetpos = digtron.find_new_pos(pos, facing)
@@ -242,7 +243,7 @@ minetest.register_node("digtron:soft_digger", {
 		type = "fixed",
 		fixed = digger_nodebox,
 	},
-	
+
 	-- Aims in the +Z direction by default
 	tiles = {
 		"digtron_plate.png^[transformR90^[colorize:" .. digtron.soft_digger_colorize,
@@ -260,23 +261,23 @@ minetest.register_node("digtron:soft_digger", {
 		},
 		"digtron_plate.png^digtron_motor.png^[colorize:" .. digtron.soft_digger_colorize,
 	},
-	
-	execute_dig = function(pos, protected_nodes, nodes_dug, controlling_coordinate, lateral_dig, player)
+
+	execute_dig = function(pos, protected_nodes, nodes_dug, _, _, player)
 		local facing = minetest.get_node(pos).param2
 		local digpos = digtron.find_new_pos(pos, facing)
-		
+
 		if protected_nodes:get(digpos.x, digpos.y, digpos.z) then
 			return 0
 		end
-			
+
 		if digtron.is_soft_material(digpos) then
 			return digtron.mark_diggable(digpos, nodes_dug, player)
 		end
-		
+
 		return 0
 	end,
 
-	damage_creatures = function(player, pos, controlling_coordinate, items_dropped)
+	damage_creatures = function(player, pos, _, items_dropped)
 		local facing = minetest.get_node(pos).param2
 		digtron.damage_creatures(player, pos, digtron.find_new_pos(pos, facing), damage_hp_half, items_dropped)
 	end,
@@ -299,7 +300,7 @@ minetest.register_node("digtron:intermittent_soft_digger", {
 		type = "fixed",
 		fixed = digger_nodebox,
 	},
-	
+
 	-- Aims in the +Z direction by default
 	tiles = {
 		"digtron_plate.png^[transformR90^[colorize:" .. digtron.soft_digger_colorize,
@@ -317,11 +318,11 @@ minetest.register_node("digtron:intermittent_soft_digger", {
 		},
 		"digtron_plate.png^digtron_intermittent.png^digtron_motor.png^[colorize:" .. digtron.soft_digger_colorize,
 	},
-	
+
 	on_construct = intermittent_on_construct,
-	
+
 	on_rightclick = intermittent_on_rightclick,
-		
+
 	execute_dig = function(pos, protected_nodes, nodes_dug, controlling_coordinate, lateral_dig, player)
 		if lateral_dig == true then
 			return 0
@@ -329,27 +330,27 @@ minetest.register_node("digtron:intermittent_soft_digger", {
 
 		local facing = minetest.get_node(pos).param2
 		local digpos = digtron.find_new_pos(pos, facing)
-		
+
 		if protected_nodes:get(digpos.x, digpos.y, digpos.z) then
 			return 0
 		end
-		
+
 		local meta = minetest.get_meta(pos)
 		if (digpos[controlling_coordinate] + meta:get_int("offset")) % meta:get_int("period") ~= 0 then
 			return 0
 		end
-		
+
 		if digtron.is_soft_material(digpos) then
 			return digtron.mark_diggable(digpos, nodes_dug, player)
 		end
-		
+
 		return 0
 	end,
 
 	damage_creatures = function(player, pos, controlling_coordinate, items_dropped)
 		local meta = minetest.get_meta(pos)
 		local facing = minetest.get_node(pos).param2
-		local targetpos = digtron.find_new_pos(pos, facing)		
+		local targetpos = digtron.find_new_pos(pos, facing)
 		if (targetpos[controlling_coordinate] + meta:get_int("offset")) % meta:get_int("period") == 0 then
 			digtron.damage_creatures(player, pos, targetpos, damage_hp_half, items_dropped)
 		end
@@ -366,13 +367,13 @@ minetest.register_node("digtron:dual_digger", {
 	sounds = digtron.metal_sounds,
 	paramtype = "light",
 	paramtype2= "facedir",
-	is_ground_content = false,	
+	is_ground_content = false,
 	drawtype="nodebox",
 	node_box = {
 		type = "fixed",
 		fixed = dual_digger_nodebox,
 	},
-	
+
 	-- Aims in the +Z and -Y direction by default
 	tiles = {
 		"digtron_plate.png^digtron_motor.png",
@@ -400,14 +401,14 @@ minetest.register_node("digtron:dual_digger", {
 	},
 
 	-- returns fuel_cost, items_produced
-	execute_dig = function(pos, protected_nodes, nodes_dug, controlling_coordinate, lateral_dig, player)
+	execute_dig = function(pos, protected_nodes, nodes_dug, _, _, player)
 		local facing = minetest.get_node(pos).param2
 		local digpos = digtron.find_new_pos(pos, facing)
 		local digdown = digtron.find_new_pos_downward(pos, facing)
 
 		local items = {}
 		local cost = 0
-		
+
 		if protected_nodes:get(digpos.x, digpos.y, digpos.z) ~= true then
 			local forward_cost, forward_items = digtron.mark_diggable(digpos, nodes_dug, player)
 			if forward_items ~= nil then
@@ -426,11 +427,11 @@ minetest.register_node("digtron:dual_digger", {
 			end
 			cost = cost + down_cost
 		end
-		
+
 		return cost, items
 	end,
-	
-	damage_creatures = function(player, pos, controlling_coordinate, items_dropped)
+
+	damage_creatures = function(player, pos, _, items_dropped)
 		local facing = minetest.get_node(pos).param2
 		digtron.damage_creatures(player, pos, digtron.find_new_pos(pos, facing), damage_hp, items_dropped)
 		digtron.damage_creatures(player, pos, digtron.find_new_pos_downward(pos, facing), damage_hp, items_dropped)
@@ -448,13 +449,13 @@ minetest.register_node("digtron:dual_soft_digger", {
 	use_texture_alpha = use_texture_alpha,
 	paramtype = "light",
 	paramtype2= "facedir",
-	is_ground_content = false,	
+	is_ground_content = false,
 	drawtype="nodebox",
 	node_box = {
 		type = "fixed",
 		fixed = dual_digger_nodebox,
 	},
-	
+
 	-- Aims in the +Z and -Y direction by default
 	tiles = {
 		"digtron_plate.png^digtron_motor.png^[colorize:" .. digtron.soft_digger_colorize,
@@ -482,14 +483,14 @@ minetest.register_node("digtron:dual_soft_digger", {
 	},
 
 	-- returns fuel_cost, items_produced
-	execute_dig = function(pos, protected_nodes, nodes_dug, controlling_coordinate, lateral_dig, player)
+	execute_dig = function(pos, protected_nodes, nodes_dug, _, _, player)
 		local facing = minetest.get_node(pos).param2
 		local digpos = digtron.find_new_pos(pos, facing)
 		local digdown = digtron.find_new_pos_downward(pos, facing)
 
 		local items = {}
 		local cost = 0
-		
+
 		if protected_nodes:get(digpos.x, digpos.y, digpos.z) ~= true and digtron.is_soft_material(digpos) then
 			local forward_cost, forward_items = digtron.mark_diggable(digpos, nodes_dug, player)
 			if forward_items ~= nil then
@@ -508,11 +509,11 @@ minetest.register_node("digtron:dual_soft_digger", {
 			end
 			cost = cost + down_cost
 		end
-		
+
 		return cost, items
 	end,
-	
-	damage_creatures = function(player, pos, controlling_coordinate, items_dropped)
+
+	damage_creatures = function(player, pos, _, items_dropped)
 		local facing = minetest.get_node(pos).param2
 		digtron.damage_creatures(player, pos, digtron.find_new_pos(pos, facing), damage_hp_half, items_dropped)
 		digtron.damage_creatures(player, pos, digtron.find_new_pos_downward(pos, facing), damage_hp_half, items_dropped)
diff --git a/nodes/node_duplicator.lua b/nodes/node_duplicator.lua
index 506aa44..95f12bb 100644
--- a/nodes/node_duplicator.lua
+++ b/nodes/node_duplicator.lua
@@ -1,6 +1,6 @@
 -- internationalization boilerplate
 local MP = minetest.get_modpath(minetest.get_current_modname())
-local S, NS = dofile(MP.."/intllib.lua")
+local S = dofile(MP.."/intllib.lua")
 
 local inventory_formspec_string =
 	"size[9,9.3]" ..
@@ -29,7 +29,8 @@ minetest.register_node("digtron:duplicator", {
     _doc_items_usagehelp = digtron.doc.duplicator_usagehelp,
 	groups = {cracky = 3,  oddly_breakable_by_hand=3},
 	sounds = digtron.metal_sounds,
-	tiles = {"digtron_plate.png^(digtron_axel_side.png^[transformR90)",
+	tiles = {
+		"digtron_plate.png^(digtron_axel_side.png^[transformR90)",
 		"digtron_plate.png^(digtron_axel_side.png^[transformR270)",
 		"digtron_plate.png^digtron_axel_side.png",
 		"digtron_plate.png^(digtron_axel_side.png^[transformR180)",
@@ -68,13 +69,13 @@ minetest.register_node("digtron:duplicator", {
 		inv:set_size("main", 8*4)
 	end,
 
-	can_dig = function(pos,player)
+	can_dig = function(pos)
 		local meta = minetest.get_meta(pos)
 		local inv = meta:get_inventory()
 		return inv:is_empty("main")
 	end,
 
-	allow_metadata_inventory_put = function(pos, listname, index, stack, player)
+	allow_metadata_inventory_put = function(_, _, _, stack)
 		if minetest.get_item_group(stack:get_name(), "digtron") > 0 then
 			return stack:get_count()
 		else
@@ -82,7 +83,7 @@ minetest.register_node("digtron:duplicator", {
 		end
 	end,
 
-	on_receive_fields = function(pos, formname, fields, sender)
+	on_receive_fields = function(pos, _, fields, sender)
 		local player_name = sender:get_player_name()
 		if fields.help then
 			minetest.after(0.5, doc.show_entry, player_name, "nodes", "digtron:duplicator", true)
@@ -113,7 +114,7 @@ minetest.register_node("digtron:duplicator", {
 				return
 			end
 
-			local layout = DigtronLayout.create(pos, sender)
+			local layout = digtron.DigtronLayout.create(pos, sender)
 
 			if layout.contains_protected_node then
 				minetest.sound_play("buzzer", {gain=0.5, pos=pos})
diff --git a/nodes/node_item_ejector.lua b/nodes/node_item_ejector.lua
index be71537..1bee4b8 100644
--- a/nodes/node_item_ejector.lua
+++ b/nodes/node_item_ejector.lua
@@ -1,13 +1,13 @@
 -- internationalization boilerplate
 local MP = minetest.get_modpath(minetest.get_current_modname())
-local S, NS = dofile(MP.."/intllib.lua")
+local S = dofile(MP.."/intllib.lua")
 
 --Build up the formspec, somewhat complicated due to multiple mod options
 local pipeworks_path = minetest.get_modpath("pipeworks")
 local doc_path = minetest.get_modpath("doc")
 local formspec_width = 1.5
 
-local ejector_formspec_string = 
+local ejector_formspec_string =
 	default.gui_bg ..
 	default.gui_bg_img ..
 	default.gui_slots
@@ -19,9 +19,9 @@ if doc_path then
 	formspec_width = formspec_width + 1.5
 end
 
-local ejector_formspec_string = "size[".. formspec_width .. ",1]" .. ejector_formspec_string
+ejector_formspec_string = "size[".. formspec_width .. ",1]" .. ejector_formspec_string
 
-local ejector_formspec = function(pos, meta)
+local ejector_formspec = function(_, meta)
 	local return_string = ejector_formspec_string
 	if pipeworks_path then
 		return_string = return_string .. "checkbox[0,0.5;nonpipe;"..S("Eject into world")..";"..meta:get_string("nonpipe").."]" ..
@@ -36,9 +36,9 @@ local function eject_items(pos, node, player, eject_even_without_pipeworks, layo
 	local destination_pos = vector.add(pos, dir)
 	local destination_node_name = minetest.get_node(destination_pos).name
 	local destination_node_def = minetest.registered_nodes[destination_node_name]
-	
+
 	if not pipeworks_path then eject_even_without_pipeworks = true end -- if pipeworks is not installed, always eject into world (there's no other option)
-	
+
 	local insert_into_pipe = false
 	local eject_into_world = false
 	if pipeworks_path and minetest.get_item_group(destination_node_name, "tubedevice") > 0 then
@@ -52,10 +52,10 @@ local function eject_items(pos, node, player, eject_even_without_pipeworks, layo
 		end
 	else
 		return false
-	end	
+	end
 
 	if layout == nil then
-		layout = DigtronLayout.create(pos, player)
+		layout = digtron.DigtronLayout.create(pos, player)
 	end
 
 	-- Build a list of all the items that builder nodes want to use.
@@ -65,7 +65,7 @@ local function eject_items(pos, node, player, eject_even_without_pipeworks, layo
 			filter_items[node_image.meta.inventory.main[1]:get_name()] = true
 		end
 	end
-	
+
 	-- Look through the inventories and find an item that's not on that list.
 	local source_node = nil
 	local source_index = nil
@@ -85,11 +85,11 @@ local function eject_items(pos, node, player, eject_even_without_pipeworks, layo
 		end
 		if source_node then break end
 	end
-	
+
 	if source_node then
 		local meta = minetest.get_meta(source_node.pos)
 		local inv = meta:get_inventory()
-		
+
 		if insert_into_pipe then
 			local from_pos = vector.add(pos, vector.multiply(dir, 0.5))
 			local start_pos = pos
@@ -129,46 +129,46 @@ minetest.register_node("digtron:inventory_ejector", {
 			{-0.1875, -0.1875, 0.3125, 0.1875, 0.1875, 0.5}, -- NodeBox3
 		}
 	},
-	
+
 	on_construct = function(pos)
 		local meta = minetest.get_meta(pos)
 		meta:set_string("autoeject", "true")
 		meta:set_string("formspec", ejector_formspec(pos, meta))
 	end,
-	
+
 	tube = (function() if pipeworks_path then return {
 		connect_sides = {back = 1}
 	} end end)(),
-	
+
 	on_punch = function(pos, node, player)
 		eject_items(pos, node, player, true)
 	end,
-	
+
 	execute_eject = function(pos, node, player, layout)
 		local meta = minetest.get_meta(pos)
 		eject_items(pos, node, player, meta:get_string("nonpipe") == "true", layout)
 	end,
-	
-	on_receive_fields = function(pos, formname, fields, sender)
+
+	on_receive_fields = function(pos, _, fields, sender)
 		local meta = minetest.get_meta(pos)
-		
+
 		if fields.help and minetest.get_modpath("doc") then --check for mod in case someone disabled it after this digger was built
 			local node_name = minetest.get_node(pos).name
 			minetest.after(0.5, doc.show_entry, sender:get_player_name(), "nodes", node_name, true)
 		end
-		
+
 		if fields.nonpipe then
 			meta:set_string("nonpipe", fields.nonpipe)
 		end
-		
+
 		if fields.autoeject then
 			meta:set_string("autoeject", fields.autoeject)
 		end
-		
+
 		meta:set_string("formspec", ejector_formspec(pos, meta))
-		
+
 	end,
-	
+
 	after_place_node = (function() if pipeworks_path then return pipeworks.after_place end end)(),
 	after_dig_node = (function() if pipeworks_path then return pipeworks.after_dig end end)()
 })
diff --git a/nodes/node_misc.lua b/nodes/node_misc.lua
index cea823e..fbf15bb 100644
--- a/nodes/node_misc.lua
+++ b/nodes/node_misc.lua
@@ -1,6 +1,6 @@
 -- internationalization boilerplate
 local MP = minetest.get_modpath(minetest.get_current_modname())
-local S, NS = dofile(MP.."/intllib.lua")
+local S = dofile(MP.."/intllib.lua")
 
 -- A do-nothing "structural" node, to ensure all digtron nodes that are supposed to be connected to each other can be connected to each other.
 minetest.register_node("digtron:structure", {
diff --git a/nodes/node_power_connector.lua b/nodes/node_power_connector.lua
index 6763b69..4347233 100644
--- a/nodes/node_power_connector.lua
+++ b/nodes/node_power_connector.lua
@@ -1,6 +1,6 @@
 -- internationalization boilerplate
 local MP = minetest.get_modpath(minetest.get_current_modname())
-local S, NS = dofile(MP.."/intllib.lua")
+local S = dofile(MP.."/intllib.lua")
 
 local size = 3/16
 
@@ -28,17 +28,21 @@ minetest.register_node("digtron:power_connector", {
 	_doc_items_longdesc = digtron.doc.power_connector_longdesc,
     _doc_items_usagehelp = digtron.doc.power_connector_usagehelp,
 	groups = connector_groups,
-	tiles = {"digtron_plate.png^digtron_power_connector_top.png^digtron_digger_yb_frame.png", "digtron_plate.png^digtron_digger_yb_frame.png",
-		"digtron_plate.png^digtron_digger_yb_frame.png^digtron_power_connector_side.png", "digtron_plate.png^digtron_digger_yb_frame.png^digtron_power_connector_side.png",
-		"digtron_plate.png^digtron_digger_yb_frame.png^digtron_power_connector_side.png", "digtron_plate.png^digtron_digger_yb_frame.png^digtron_power_connector_side.png",
-		},
+	tiles = {
+		"digtron_plate.png^digtron_power_connector_top.png^digtron_digger_yb_frame.png",
+		"digtron_plate.png^digtron_digger_yb_frame.png",
+		"digtron_plate.png^digtron_digger_yb_frame.png^digtron_power_connector_side.png",
+		"digtron_plate.png^digtron_digger_yb_frame.png^digtron_power_connector_side.png",
+		"digtron_plate.png^digtron_digger_yb_frame.png^digtron_power_connector_side.png",
+		"digtron_plate.png^digtron_digger_yb_frame.png^digtron_power_connector_side.png",
+	},
 	connect_sides = {"bottom", "top", "left", "right", "front", "back"},
 	drawtype = "nodebox",
 	sounds = digtron.metal_sounds,
 	paramtype = "light",
 	paramtype2 = "facedir",
 	is_ground_content = false,
-	
+
 	connects_to = {"group:technic_hv_cable"},
 	node_box = {
 		type = "connected",
@@ -53,45 +57,45 @@ minetest.register_node("digtron:power_connector", {
 		connect_left   = {-0.5,  -size, -size, size,  size, size}, -- x-
 		connect_right  = {-size, -size, -size, 0.5,   size, size}, -- x+
 	},
-	
+
 	on_construct = function(pos)
 		local meta = minetest.get_meta(pos)
 		meta:set_string("formspec", get_formspec_string(0,0))
 	end,
 
-	technic_run = function(pos, node)
+	technic_run = function(pos)
 		local meta = minetest.get_meta(pos)
 		local eu_input = meta:get_int("HV_EU_input")
 		local demand = meta:get_int("HV_EU_demand")
 		meta:set_string("infotext", S("Digtron Power @1/@2", eu_input, demand))
 	end,
-	
-	on_receive_fields = function(pos, formname, fields, sender)
-		local layout = DigtronLayout.create(pos, sender)
+
+	on_receive_fields = function(pos, _, fields, sender)
+		local layout = digtron.DigtronLayout.create(pos, sender)
 		local max_cost = 0
 		if layout.builders ~= nil then
 			for _, node_image in pairs(layout.builders) do
 				max_cost = max_cost + (digtron.config.build_cost * (node_image.meta.fields.extrusion or 1))
-			end 
+			end
 		end
 		if layout.diggers ~= nil then
-			for _, node_image in pairs(layout.diggers) do
+			for _ in pairs(layout.diggers) do
 				max_cost = max_cost + max_dig_cost
 			end
 		end
 		local current_max = max_cost * digtron.config.power_ratio
-	
+
 		local meta = minetest.get_meta(pos)
-		
+
 		if fields.maximize then
 			meta:set_int("HV_EU_demand", current_max)
 		elseif fields.value ~= nil then
 			local number = tonumber(fields.value) or 0
-			local number = math.min(math.max(number, 0), current_max)
+			number = math.min(math.max(number, 0), current_max)
 			meta:set_int("HV_EU_demand", number)
 		end
-	
-		meta:set_string("formspec", get_formspec_string(meta:get_int("HV_EU_demand"), current_max))	
+
+		meta:set_string("formspec", get_formspec_string(meta:get_int("HV_EU_demand"), current_max))
 	end,
 })
 
diff --git a/nodes/node_storage.lua b/nodes/node_storage.lua
index 6237e66..f13d81e 100644
--- a/nodes/node_storage.lua
+++ b/nodes/node_storage.lua
@@ -1,10 +1,10 @@
 -- internationalization boilerplate
 local MP = minetest.get_modpath(minetest.get_current_modname())
-local S, NS = dofile(MP.."/intllib.lua")
+local S = dofile(MP.."/intllib.lua")
 
 local pipeworks_path = minetest.get_modpath("pipeworks")
 
-local inventory_formspec_string = 
+local inventory_formspec_string =
 	"size[8,9.3]" ..
 	default.gui_bg ..
 	default.gui_bg_img ..
@@ -17,7 +17,7 @@ local inventory_formspec_string =
 	"listring[current_player;main]" ..
 	default.get_hotbar_bg(0,5.15)
 
-local inventory_formspec = function(pos, meta)
+local inventory_formspec = function()
 	return inventory_formspec_string
 end
 
@@ -56,23 +56,23 @@ minetest.register_node("digtron:inventory", {
 		local inv = meta:get_inventory()
 		inv:set_size("main", 8*4)
 	end,
-	
-	can_dig = function(pos,player)
+
+	can_dig = function(pos)
 		local meta = minetest.get_meta(pos)
 		local inv = meta:get_inventory()
 		return inv:is_empty("main")
 	end,
-		
+
 	-- Pipeworks compatibility
 	----------------------------------------------------------------
 
 	tube = (function() if pipeworks_path then return {
-		insert_object = function(pos, node, stack, direction)
+		insert_object = function(pos, _, stack)
 			local meta = minetest.get_meta(pos)
 			local inv = meta:get_inventory()
 			return inv:add_item("main", stack)
 		end,
-		can_insert = function(pos, node, stack, direction)
+		can_insert = function(pos, _, stack)
 			local meta = minetest.get_meta(pos)
 			local inv = meta:get_inventory()
 			return inv:room_for_item("main", stack)
@@ -80,12 +80,12 @@ minetest.register_node("digtron:inventory", {
 		input_inventory = "main",
 		connect_sides = {left = 1, right = 1, back = 1, front = 1, bottom = 1, top = 1}
 	} end end)(),
-	
+
 	after_place_node = (function() if pipeworks_path then return pipeworks.after_place end end)(),
 	after_dig_node = (function() if pipeworks_path then return pipeworks.after_dig end end)()
 })
 
-local fuelstore_formspec_string = 
+local fuelstore_formspec_string =
 	"size[8,9.3]" ..
 	default.gui_bg ..
 	default.gui_bg_img ..
@@ -98,10 +98,10 @@ local fuelstore_formspec_string =
 	"listring[current_player;main]" ..
 	default.get_hotbar_bg(0,5.15)
 
-local fuelstore_formspec = function(pos, meta)
+local fuelstore_formspec = function()
 	return fuelstore_formspec_string
 end
-	
+
 -- Fuel storage. Controller node draws fuel from here.
 -- Note that fuel stores are digtron group 5.
 minetest.register_node("digtron:fuelstore", {
@@ -137,9 +137,9 @@ minetest.register_node("digtron:fuelstore", {
 		local inv = meta:get_inventory()
 		inv:set_size("fuel", 8*4)
 	end,
-	
+
 	-- Only allow fuel items to be placed in fuel
-	allow_metadata_inventory_put = function(pos, listname, index, stack, player)
+	allow_metadata_inventory_put = function(_, listname, _, stack)
 		if listname == "fuel" then
 			if minetest.get_craft_result({method="fuel", width=1, items={stack}}).time ~= 0 then
 				return stack:get_count()
@@ -149,18 +149,18 @@ minetest.register_node("digtron:fuelstore", {
 		end
 		return 0
 	end,
-	
-	can_dig = function(pos,player)
+
+	can_dig = function(pos)
 		local meta = minetest.get_meta(pos)
 		local inv = meta:get_inventory()
 		return inv:is_empty("fuel")
 	end,
-		
+
 	-- Pipeworks compatibility
 	----------------------------------------------------------------
 
 	tube = (function() if pipeworks_path then return {
-		insert_object = function(pos, node, stack, direction)
+		insert_object = function(pos, _, stack)
 			if minetest.get_craft_result({method="fuel", width=1, items={stack}}).time ~= 0 then
 				local meta = minetest.get_meta(pos)
 				local inv = meta:get_inventory()
@@ -168,7 +168,7 @@ minetest.register_node("digtron:fuelstore", {
 			end
 			return stack
 		end,
-		can_insert = function(pos, node, stack, direction)
+		can_insert = function(pos, _, stack)
 			if minetest.get_craft_result({method="fuel", width=1, items={stack}}).time ~= 0 then
 				local meta = minetest.get_meta(pos)
 				local inv = meta:get_inventory()
@@ -179,7 +179,7 @@ minetest.register_node("digtron:fuelstore", {
 		input_inventory = "fuel",
 		connect_sides = {left = 1, right = 1, back = 1, front = 1, bottom = 1, top = 1}
 	} end end)(),
-	
+
 	after_place_node = (function() if pipeworks_path then return pipeworks.after_place end end)(),
 	after_dig_node = (function() if pipeworks_path then return pipeworks.after_dig end end)()
 })
@@ -199,7 +199,7 @@ local combined_storage_formspec_string =
 	"listring[current_player;main]" ..
 	default.get_hotbar_bg(0,5.75)
 
-local combined_storage_formspec = function(pos, meta)
+local combined_storage_formspec = function()
 	return combined_storage_formspec_string
 end
 
@@ -224,7 +224,8 @@ minetest.register_node("digtron:combined_storage", {
 	is_ground_content = false,
 	tiles = {
 		"digtron_plate.png^digtron_crossbrace.png^digtron_flammable_small.png^[transformR180^digtron_flammable_small.png",
-		"digtron_plate.png^digtron_crossbrace.png^digtron_flammable_small.png^[transformR180^digtron_flammable_small.png",		"digtron_plate.png^digtron_crossbrace.png^digtron_flammable_small.png^digtron_storage.png",
+		"digtron_plate.png^digtron_crossbrace.png^digtron_flammable_small.png^[transformR180^digtron_flammable_small.png",
+		"digtron_plate.png^digtron_crossbrace.png^digtron_flammable_small.png^digtron_storage.png",
 		"digtron_plate.png^digtron_crossbrace.png^digtron_flammable_small.png^digtron_storage.png",
 		"digtron_plate.png^digtron_crossbrace.png^digtron_flammable_small.png^digtron_storage.png",
 		"digtron_plate.png^digtron_crossbrace.png^digtron_flammable_small.png^digtron_storage.png",
@@ -236,9 +237,9 @@ minetest.register_node("digtron:combined_storage", {
 		inv:set_size("main", 8*3)
 		inv:set_size("fuel", 8*1)
 	end,
-	
+
 	-- Only allow fuel items to be placed in fuel
-	allow_metadata_inventory_put = function(pos, listname, index, stack, player)
+	allow_metadata_inventory_put = function(_, listname, _, stack)
 		if listname == "fuel" then
 			if minetest.get_craft_result({method="fuel", width=1, items={stack}}).time ~= 0 then
 				return stack:get_count()
@@ -248,12 +249,12 @@ minetest.register_node("digtron:combined_storage", {
 		end
 		return stack:get_count() -- otherwise, allow all drops
 	end,
-	
-	allow_metadata_inventory_move = function(pos, from_list, from_index, to_list, to_index, count, player)
+
+	allow_metadata_inventory_move = function(pos, from_list, from_index, to_list, _, count)
 		if to_list == "main" then
 			return count
 		end
-		
+
 		local meta = minetest.get_meta(pos)
 		local inv = meta:get_inventory()
 		local stack = inv:get_stack(from_list, from_index)
@@ -262,17 +263,17 @@ minetest.register_node("digtron:combined_storage", {
 		end
 		return 0
 	end,
-	
-	can_dig = function(pos,player)
+
+	can_dig = function(pos)
 		local meta = minetest.get_meta(pos)
 		local inv = meta:get_inventory()
 		return inv:is_empty("fuel") and inv:is_empty("main")
 	end,
-		
+
 	-- Pipeworks compatibility
 	----------------------------------------------------------------
 	tube = (function() if pipeworks_path then return {
-		insert_object = function(pos, node, stack, direction)
+		insert_object = function(pos, _, stack, direction)
 			local meta = minetest.get_meta(pos)
 			local inv = meta:get_inventory()
 			if minetest.get_craft_result({method="fuel", width=1, items={stack}}).time ~= 0 and direction.y == 1 then
@@ -280,7 +281,7 @@ minetest.register_node("digtron:combined_storage", {
 			end
 			return inv:add_item("main", stack)
 		end,
-		can_insert = function(pos, node, stack, direction)
+		can_insert = function(pos, _, stack, direction)
 			local meta = minetest.get_meta(pos)
 			local inv = meta:get_inventory()
 			if minetest.get_craft_result({method="fuel", width=1, items={stack}}).time ~= 0 and direction.y == 1 then
@@ -291,7 +292,7 @@ minetest.register_node("digtron:combined_storage", {
 		input_inventory = "main",
 		connect_sides = {left = 1, right = 1, back = 1, front = 1, bottom = 1, top = 1}
 	} end end)(),
-	
+
 	after_place_node = (function() if pipeworks_path then return pipeworks.after_place end end)(),
 	after_dig_node = (function() if pipeworks_path then return pipeworks.after_dig end end)()
 })
@@ -306,7 +307,7 @@ if minetest.get_modpath("hopper") and hopper ~= nil and hopper.add_container ~=
 		{"top", "digtron:fuelstore", "fuel"},
 		{"bottom", "digtron:fuelstore", "fuel"},
 		{"side", "digtron:fuelstore", "fuel"},
-	
+
 		{"top", "digtron:combined_storage", "main"},
 		{"bottom", "digtron:combined_storage", "main"},
 		{"side", "digtron:combined_storage", "fuel"},
diff --git a/nodes/recipes.lua b/nodes/recipes.lua
index a907cbf..ce10303 100644
--- a/nodes/recipes.lua
+++ b/nodes/recipes.lua
@@ -1,6 +1,6 @@
 -- internationalization boilerplate
 local MP = minetest.get_modpath(minetest.get_current_modname())
-local S, NS = dofile(MP.."/intllib.lua")
+local S = dofile(MP.."/intllib.lua")
 
 minetest.register_craftitem("digtron:digtron_core", {
 	description = S("Digtron Core"),
@@ -120,7 +120,7 @@ if minetest.get_modpath("technic") then
 				{"","default:steel_ingot",""}
 				}
 	})
-	
+
 	minetest.register_craft({
 		output = "digtron:power_connector",
 		recipe = {
diff --git a/upgrades.lua b/upgrades.lua
index dc19053..fb289e5 100644
--- a/upgrades.lua
+++ b/upgrades.lua
@@ -28,19 +28,19 @@ minetest.register_lbm({
 minetest.register_lbm({
 	name = "digtron:fuelstore_upgrade",
 	nodenames = {"digtron:fuelstore"},
-	action = function(pos, node)
+	action = function(pos)
 		local meta = minetest.get_meta(pos)
 		local inv = meta:get_inventory()
 		local list = inv:get_list("main")
 		inv:set_list("main", {})
-		inv:set_list("fuel", list)		
+		inv:set_list("fuel", list)
 	end
 })
 
 minetest.register_lbm({
 	name = "digtron:autocontroller_lateral_upgrade",
 	nodenames = {"digtron:auto_controller"},
-	action = function(pos, node)
+	action = function(pos)
 		local meta = minetest.get_meta(pos)
 		local cycles = meta:get_int("offset")
 		meta:set_int("cycles", cycles)
@@ -52,7 +52,7 @@ minetest.register_lbm({
 minetest.register_lbm({
 	name = "digtron:builder_extrusion_upgrade",
 	nodenames = {"digtron:builder"},
-	action = function(pos, node)
+	action = function(pos)
 		local meta = minetest.get_meta(pos)
 		meta:set_int("extrusion", 1)
 	end
diff --git a/util.lua b/util.lua
index 2ce2492..1818ae0 100644
--- a/util.lua
+++ b/util.lua
@@ -43,7 +43,7 @@ digtron.mark_diggable = function(pos, nodes_dug, player)
 	-- returns fuel cost and what will be dropped by digging these nodes.
 
 	local target = minetest.get_node(pos)
-	
+
 	-- prevent digtrons from being marked for digging.
 	if minetest.get_item_group(target.name, "digtron") ~= 0 or
 		minetest.get_item_group(target.name, "digtron_protected") ~= 0 or
@@ -57,7 +57,7 @@ digtron.mark_diggable = function(pos, nodes_dug, player)
 		if target.name ~= "air" then
 			local in_known_group = false
 			local material_cost = 0
-			
+
 			if digtron.config.uses_resources then
 				if minetest.get_item_group(target.name, "cracky") ~= 0 then
 					in_known_group = true
@@ -75,13 +75,13 @@ digtron.mark_diggable = function(pos, nodes_dug, player)
 					material_cost = digtron.config.dig_cost_default
 				end
 			end
-	
+
 			return material_cost, minetest.get_node_drops(target.name, "")
 		end
 	end
 	return 0
 end
-	
+
 digtron.can_build_to = function(pos, protected_nodes, dug_nodes)
 	-- Returns whether a space is clear to have something put into it
 
@@ -115,7 +115,7 @@ digtron.place_in_inventory = function(itemname, inventory_positions, fallback_po
 	--tries placing the item in each inventory node in turn. If there's no room, drop it at fallback_pos
 	local itemstack = ItemStack(itemname)
 	if inventory_positions ~= nil then
-		for k, location in pairs(inventory_positions) do
+		for _, location in pairs(inventory_positions) do
 			node_inventory_table.pos = location.pos
 			local inv = minetest.get_inventory(node_inventory_table)
 			itemstack = inv:add_item("main", itemstack)
@@ -147,7 +147,7 @@ digtron.take_from_inventory = function(itemname, inventory_positions)
 	if inventory_positions == nil then return nil end
 	--tries to take an item from each inventory node in turn. Returns location of inventory item was taken from on success, nil on failure
 	local itemstack = ItemStack(itemname)
-	for k, location in pairs(inventory_positions) do
+	for _, location in pairs(inventory_positions) do
 		node_inventory_table.pos = location.pos
 		local inv = minetest.get_inventory(node_inventory_table)
 		local output = inv:remove_item("main", itemstack)
@@ -158,8 +158,8 @@ digtron.take_from_inventory = function(itemname, inventory_positions)
 	return nil
 end
 
--- Used to determine which coordinate is being checked for periodicity. eg, if the digtron is moving in the z direction, then periodicity is checked for every n nodes in the z axis.
-digtron.get_controlling_coordinate = function(pos, facedir)
+-- Used to determine which coordinate is being checked for periodicity. eg, if the digtron is moving in the z direction, then periodicity is checked for every n nodes in the z axis
+digtron.get_controlling_coordinate = function(_, facedir)
 	-- used for determining builder period and offset
 	local dir = digtron.facedir_to_dir_map[facedir]
 	if dir == 1 or dir == 3 then
@@ -172,7 +172,7 @@ digtron.get_controlling_coordinate = function(pos, facedir)
 end
 
 local fuel_craft = {method="fuel", width=1, items={}} -- reusable crafting recipe table for get_craft_result calls below
--- Searches fuel store inventories for burnable items and burns them until target is reached or surpassed 
+-- Searches fuel store inventories for burnable items and burns them until target is reached or surpassed
 -- (or there's nothing left to burn). Returns the total fuel value burned
 -- if the "test" parameter is set to true, doesn't actually take anything out of inventories.
 -- We can get away with this sort of thing for fuel but not for builder inventory because there's just one
@@ -183,7 +183,7 @@ digtron.burn = function(fuelstore_positions, target, test)
 	end
 
 	local current_burned = 0
-	for k, location in pairs(fuelstore_positions) do
+	for _, location in pairs(fuelstore_positions) do
 		if current_burned > target then
 			break
 		end
@@ -194,8 +194,8 @@ digtron.burn = function(fuelstore_positions, target, test)
 		if invlist == nil then -- This check shouldn't be needed, it's yet another guard against https://github.com/minetest/minetest/issues/8067
 			break
 		end
-		
-		for i, itemstack in pairs(invlist) do
+
+		for _, itemstack in pairs(invlist) do
 			fuel_craft.items[1] = itemstack:peek_item(1)
 			local fuel_per_item = minetest.get_craft_result(fuel_craft).time
 			if fuel_per_item ~= 0 then
@@ -222,8 +222,8 @@ digtron.burn = function(fuelstore_positions, target, test)
 end
 
 -- Consume energy from the batteries
--- The same as burning coal, except that instead of destroying the items in the inventory, we merely drain 
--- the charge in them, leaving them empty. The charge is converted into "coal heat units" by a downscaling 
+-- The same as burning coal, except that instead of destroying the items in the inventory, we merely drain
+-- the charge in them, leaving them empty. The charge is converted into "coal heat units" by a downscaling
 -- factor, since if taken at face value (10000 EU), the batteries would be the ultimate power source barely
 -- ever needing replacement.
 digtron.tap_batteries = function(battery_positions, target, test)
@@ -237,20 +237,20 @@ digtron.tap_batteries = function(battery_positions, target, test)
 	-- An RE battery holds 10000 EU of charge
 	-- local power_ratio = 100 -- How much charge equals 1 unit of PU from coal
 	-- setting Moved to digtron.config.power_ratio
-	
-	for k, location in pairs(battery_positions) do
+
+	for _, location in pairs(battery_positions) do
 		if current_burned > target then
 			break
 		end
 		node_inventory_table.pos = location.pos
 		local inv = minetest.get_inventory(node_inventory_table)
 		local invlist = inv:get_list("batteries")
-		
+
 		if (invlist == nil) then -- This check shouldn't be needed, it's yet another guard against https://github.com/minetest/minetest/issues/8067
 			break
 		end
-		
-		for i, itemstack in pairs(invlist) do
+
+		for _, itemstack in pairs(invlist) do
 			local meta = minetest.deserialize(itemstack:get_metadata())
 			if (meta ~= nil) then
 				local power_available = math.floor(meta.charge / digtron.config.power_ratio)
@@ -265,14 +265,13 @@ digtron.tap_batteries = function(battery_positions, target, test)
 					end
 					current_burned = current_burned + actual_burned
 				end
-			
 			end
-			
+
 			if current_burned > target then
 				break
 			end
 		end
-				
+
 		if test ~= true then
 			-- only update the list if we're doing this for real.
 			inv:set_list("batteries", invlist)
@@ -363,7 +362,7 @@ digtron.damage_creatures = function(player, source_pos, target_pos, amount, item
 					obj:remove()
 				end
 			end
-		end		
+		end
 	end
 end
 
@@ -382,8 +381,8 @@ end
 -- If someone sets very large offsets or intervals for the offset markers they might be added too far
 -- away. safe_add_entity causes these attempts to be ignored rather than crashing the game.
 -- returns the entity if successful, nil otherwise
-function safe_add_entity(pos, name)
-	success, ret = pcall(minetest.add_entity, pos, name)
+local function safe_add_entity(pos, name)
+	local success, ret = pcall(minetest.add_entity, pos, name)
 	if success then return ret else return nil end
 end
 
@@ -411,13 +410,13 @@ digtron.show_offset_markers = function(pos, offset, period)
 
 	local entity = safe_add_entity({x=buildpos.x, y=buildpos.y, z=z_pos}, "digtron:marker")
 	if entity ~= nil then entity:setyaw(1.5708) end
-	
+
 	if z_pos >= buildpos.z then
-		local entity = safe_add_entity({x=buildpos.x, y=buildpos.y, z=z_pos - period}, "digtron:marker")
+		entity = safe_add_entity({x=buildpos.x, y=buildpos.y, z=z_pos - period}, "digtron:marker")
 		if entity ~= nil then entity:setyaw(1.5708) end
 	end
 	if z_pos <= buildpos.z then
-		local entity = safe_add_entity({x=buildpos.x, y=buildpos.y, z=z_pos + period}, "digtron:marker")
+		entity = safe_add_entity({x=buildpos.x, y=buildpos.y, z=z_pos + period}, "digtron:marker")
 		if entity ~= nil then entity:setyaw(1.5708) end
 	end
 end
diff --git a/util_execute_cycle.lua b/util_execute_cycle.lua
index eea6476..5d6a629 100644
--- a/util_execute_cycle.lua
+++ b/util_execute_cycle.lua
@@ -1,6 +1,6 @@
 -- internationalization boilerplate
 local MP = minetest.get_modpath(minetest.get_current_modname())
-local S, NS = dofile(MP.."/intllib.lua")
+local S = dofile(MP.."/intllib.lua")
 
 local dig_dust = function(pos, facing)
 	local direction = minetest.facedir_to_dir(facing)
@@ -50,15 +50,15 @@ local function neighbour_test(layout, status_text, dir)
 		minetest.sound_play("buzzer", {gain=0.25, pos=layout.controller})
 		return S("Digtron is adjacent to unloaded nodes.") .. "\n" .. status_text, 1
 	end
-	
+
 	if layout.water_touching == true then
 		minetest.sound_play("sploosh", {gain=1.0, pos=layout.controller})
 	end
-	
+
 	if layout.lava_touching == true then
 		minetest.sound_play("woopwoopwoop", {gain=1.0, pos=layout.controller})
-	end	
-	
+	end
+
 	if dir and dir.y ~= -1 and layout.traction * digtron.config.traction_factor < table.getn(layout.all) then
 		-- digtrons can't fly, though they can fall
 		minetest.sound_play("squeal", {gain=1.0, pos=layout.controller})
@@ -117,11 +117,11 @@ digtron.execute_dig_cycle = function(pos, clicker)
 	local dir = minetest.facedir_to_dir(facing)
 	local fuel_burning = meta:get_float("fuel_burning") -- get amount of burned fuel left over from last cycle
 	local status_text = S("Heat remaining in controller furnace: @1", math.floor(math.max(0, fuel_burning)))
-	local exhaust = meta:get_int("on_coal")
-	
-	local layout = DigtronLayout.create(pos, clicker)
 
-	local status_text, return_code = neighbour_test(layout, status_text, dir)
+	local layout = digtron.DigtronLayout.create(pos, clicker)
+
+	local return_code
+	status_text, return_code = neighbour_test(layout, status_text, dir)
 	if return_code ~= 0 then
 		return pos, status_text, return_code
 	end
@@ -130,21 +130,21 @@ digtron.execute_dig_cycle = function(pos, clicker)
 	if size_check_error then
 		return pos, size_check_error, 8
 	end
-	
+
 	local controlling_coordinate = digtron.get_controlling_coordinate(pos, facing)
-	
+
 	----------------------------------------------------------------------------------------------------------------------
-	
+
 	local items_dropped = {}
 	local digging_fuel_cost = 0
 	local particle_systems = {}
-	
+
 	-- execute the execute_dig method on all digtron components that have one
 	-- This builds a set of nodes that will be dug and returns a list of products that will be generated
 	-- but doesn't actually dig the nodes yet. That comes later.
 	-- If we dug them now, sand would fall and some digtron nodes would die.
 	if layout.diggers ~= nil then
-		for k, location in pairs(layout.diggers) do
+		for _, location in pairs(layout.diggers) do
 			local target = minetest.get_node(location.pos)
 			local targetdef = minetest.registered_nodes[target.name]
 			if targetdef.execute_dig ~= nil then
@@ -163,9 +163,9 @@ digtron.execute_dig_cycle = function(pos, clicker)
 			end
 		end
 	end
-	
+
 	----------------------------------------------------------------------------------------------------------------------
-	
+
 	-- test if any digtrons are obstructed by non-digtron nodes that haven't been marked
 	-- as having been dug.
 	local can_move = true
@@ -175,11 +175,11 @@ digtron.execute_dig_cycle = function(pos, clicker)
 			can_move = false
 		end
 	end
-	
+
 	if test_stop_block(pos, items_dropped) then
 		can_move = false
 	end
-	
+
 	if not can_move then
 		-- mark this node as waiting, will clear this flag in digtron.config.cycle_time seconds
 		minetest.get_meta(pos):set_string("waiting", "true")
@@ -190,26 +190,26 @@ digtron.execute_dig_cycle = function(pos, clicker)
 	end
 
 	----------------------------------------------------------------------------------------------------------------------
-	
+
 	-- ask each builder node if it can get what it needs from inventory to build this cycle.
 	-- This is a complicated test because each builder needs to actually *take* the item it'll
 	-- need from inventory, and then we put it all back afterward.
 	-- Note that this test may overestimate the amount of work that will actually need to be done so don't treat its fuel cost as authoritative.
 	local can_build = true
-	local test_build_return_code = nil
-	local test_build_return_items = nil
-	local failed_to_find = nil
 	local test_items = {}
-	local test_fuel_items = {}
 	local test_build_fuel_cost = 0
+	local test_build_return_code, test_build_return_items, failed_to_find
+
 	if layout.builders ~= nil then
-		for k, location in pairs(layout.builders) do
+		for _, location in pairs(layout.builders) do
 			local target = minetest.get_node(location.pos)
 			local targetdef = minetest.registered_nodes[target.name]
 			local test_location = vector.add(location.pos, dir)
 			if targetdef.test_build ~= nil then
-				test_build_return_code, test_build_return_items, failed_to_find = targetdef.test_build(location.pos, test_location, layout.inventories, layout.protected, layout.nodes_dug, controlling_coordinate, layout.controller)
-				for k, return_item in pairs(test_build_return_items) do
+				test_build_return_code, test_build_return_items, failed_to_find = targetdef.test_build(
+					location.pos, test_location, layout.inventories, layout.protected, layout.nodes_dug, controlling_coordinate, layout.controller
+				)
+				for _, return_item in pairs(test_build_return_items) do
 					table.insert(test_items, return_item)
 					test_build_fuel_cost = test_build_fuel_cost + digtron.config.build_cost
 				end
@@ -222,7 +222,7 @@ digtron.execute_dig_cycle = function(pos, clicker)
 			end
 		end
 	end
-	
+
 	local test_fuel_needed = test_build_fuel_cost + digging_fuel_cost - fuel_burning
 	local test_fuel_burned = 0
 
@@ -248,7 +248,7 @@ digtron.execute_dig_cycle = function(pos, clicker)
 			power_from_cables = power_from_cables / digtron.config.power_ratio
 			test_fuel_burned = power_from_cables
 		end
-		
+
 		if test_fuel_needed - test_fuel_burned > 0 then
 			-- check for the available electrical power
 			test_fuel_burned = test_fuel_burned + digtron.tap_batteries(layout.battery_holders, test_fuel_needed, true)
@@ -257,31 +257,32 @@ digtron.execute_dig_cycle = function(pos, clicker)
 	if (fuel_burning<0) then
 		test_fuel_needed = test_fuel_needed - fuel_burning
 		fuel_burning = 0
-	end	
+	end
 
+	local exhaust
 	if (test_fuel_needed < test_fuel_burned) then
 		exhaust = 0 -- all power needs met by electricity, don't blow smoke
-	else 
+	else
 		-- burn combustible fuel if not enough power
 		test_fuel_burned = test_fuel_burned + digtron.burn(layout.fuelstores, test_fuel_needed - test_fuel_burned, true)
 		exhaust = 1 -- burning fuel produces smoke
 	end
-	
+
 	--Put everything back where it came from
-	for k, item_return in pairs(test_items) do
+	for _, item_return in pairs(test_items) do
 		digtron.place_in_specific_inventory(item_return.item, item_return.location, layout.inventories, layout.controller)
 	end
-	
+
 	if test_fuel_needed > fuel_burning + test_fuel_burned then
 		minetest.sound_play("buzzer", {gain=0.5, pos=pos})
 		return pos, S("Digtron needs more fuel."), 4 -- abort, don't dig and don't build.
 	end
-	
+
 	if not can_build then
 		minetest.get_meta(pos):set_string("waiting", "true")
 		minetest.get_node_timer(pos):start(digtron.config.cycle_time)
 		local return_string = nil
-		local return_code = 5
+		return_code = 5
 		if test_build_return_code == 3 then
 			minetest.sound_play("honk", {gain=0.5, pos=pos}) -- A builder is not configured
 			return_string = S("Digtron connected to at least one builder with no output material assigned.") .. "\n"
@@ -292,19 +293,19 @@ digtron.execute_dig_cycle = function(pos, clicker)
 			return_code = 7
 		end
 		return pos, return_string .. status_text, return_code --Abort, don't dig and don't build.
-	end	
+	end
 
 	----------------------------------------------------------------------------------------------------------------------
-	
+
 	-- All tests passed, ready to go for real!
 	minetest.sound_play("construction", {gain=1.0, pos=pos})
 
 	-- if the player is standing within the array or next to it, move him too.
 	local move_player = move_player_test(layout, clicker)
-	
+
 	-- damage the weak flesh
 	if digtron.config.damage_hp > 0 and layout.diggers ~= nil then
-		for k, location in pairs(layout.diggers) do
+		for _, location in pairs(layout.diggers) do
 			local target = minetest.get_node(location.pos)
 			local targetdef = minetest.registered_nodes[target.name]
 			if targetdef.damage_creatures ~= nil then
@@ -312,7 +313,7 @@ digtron.execute_dig_cycle = function(pos, clicker)
 			end
 		end
 	end
-	
+
 	--move the array
 	layout:move_layout_image(dir)
 	if not layout:write_layout_image(clicker) then
@@ -324,18 +325,18 @@ digtron.execute_dig_cycle = function(pos, clicker)
 	if move_player then
 		clicker:moveto(vector.add(dir, clicker:get_pos()), true)
 	end
-	
+
 	-- store or drop the products of the digger heads
 	for _, itemname in pairs(items_dropped) do
 		digtron.place_in_inventory(itemname, layout.inventories, oldpos)
 	end
 	digtron.award_item_dug(items_dropped, clicker) -- Achievements mod hook
-	
+
 	local building_fuel_cost = 0
 	local strange_failure = false
 	-- execute_build on all digtron components that have one
 	if layout.builders ~= nil then
-		for k, location in pairs(layout.builders) do
+		for _, location in pairs(layout.builders) do
 			local target = minetest.get_node(location.pos)
 			local targetdef = minetest.registered_nodes[target.name]
 			if targetdef.execute_build ~= nil then
@@ -346,7 +347,6 @@ digtron.execute_dig_cycle = function(pos, clicker)
 					-- So this should never happen. However, "should never happens" happen sometimes. So
 					-- don't interrupt the build cycle as a whole, we've already moved so might as well try to complete as much as possible.
 					strange_failure = true
-					build_return = (build_return * -1) - 1
 				elseif digtron.config.uses_resources then
 					building_fuel_cost = building_fuel_cost + (digtron.config.build_cost * build_return)
 				end
@@ -355,9 +355,9 @@ digtron.execute_dig_cycle = function(pos, clicker)
 			end
 		end
 	end
-	
+
 	if layout.auto_ejectors ~= nil then
-		for k, location in pairs(layout.auto_ejectors) do
+		for _, location in pairs(layout.auto_ejectors) do
 			local target = minetest.get_node(location.pos)
 			local targetdef = minetest.registered_nodes[target.name]
 			if targetdef.execute_eject ~= nil then
@@ -368,16 +368,16 @@ digtron.execute_dig_cycle = function(pos, clicker)
 		end
 	end
 
-	local status_text = ""
+	status_text = ""
 	if strange_failure then
 		-- We weren't able to detect this build failure ahead of time, so make a big noise now. This is strange, shouldn't happen.
 		minetest.sound_play("dingding", {gain=1.0, pos=pos})
 		minetest.sound_play("buzzer", {gain=0.5, pos=pos})
 		status_text = S("Digtron unexpectedly failed to execute one or more build operations, likely due to an inventory error.") .. "\n"
 	end
-	
+
 	local total_fuel_cost = math.max(digging_fuel_cost + building_fuel_cost - power_from_cables, 0)
-	
+
 	-- actually burn the fuel needed
 	fuel_burning = fuel_burning - total_fuel_cost
 	if digtron.config.particle_effects and exhaust == 1 then
@@ -391,7 +391,7 @@ digtron.execute_dig_cycle = function(pos, clicker)
 			fuel_burning = fuel_burning + digtron.burn(layout.fuelstores, -fuel_burning, false)
 		end
 	end
-	                                        
+
 	meta:set_float("fuel_burning", fuel_burning)
 	meta:set_int("on_coal", exhaust)
 	status_text = status_text .. S("Heat remaining in controller furnace: @1", math.floor(math.max(0, fuel_burning)))
@@ -400,13 +400,15 @@ digtron.execute_dig_cycle = function(pos, clicker)
 	for _, particles in pairs(particle_systems) do
 		minetest.add_particlespawner(particles)
 	end
-	
+
 	-- finally, dig out any nodes remaining to be dug. Some of these will have had their flag revoked because
 	-- a builder put something there or because they're another digtron node.
 	local node_to_dig, whether_to_dig = layout.nodes_dug:pop()
 	while node_to_dig ~= nil do
 		if whether_to_dig == true then
-			minetest.log("action", string.format("%s uses Digtron to dig %s at (%d, %d, %d)", clicker:get_player_name(), minetest.get_node(node_to_dig).name, node_to_dig.x, node_to_dig.y, node_to_dig.z))
+			minetest.log("action", string.format(
+				"%s uses Digtron to dig %s at (%d, %d, %d)", clicker:get_player_name(), minetest.get_node(node_to_dig).name, node_to_dig.x, node_to_dig.y, node_to_dig.z)
+			)
 			minetest.remove_node(node_to_dig)
 		end
 		-- all of the digtron's nodes wind up in nodes_dug, so this is an ideal place to stick
@@ -420,11 +422,11 @@ end
 
 -- Simplified version of the above method that only moves, and doesn't execute diggers or builders.
 digtron.execute_move_cycle = function(pos, clicker)
-	local meta = minetest.get_meta(pos)
-	local layout = DigtronLayout.create(pos, clicker)
+	local layout = digtron.DigtronLayout.create(pos, clicker)
 
 	local status_text = ""
-	local status_text, return_code = neighbour_test(layout, status_text, nil) -- skip traction check for pusher by passing nil for direction
+	local return_code
+	status_text, return_code = neighbour_test(layout, status_text, nil) -- skip traction check for pusher by passing nil for direction
 	if return_code ~= 0 then
 		return pos, status_text, return_code
 	end
@@ -436,11 +438,10 @@ digtron.execute_move_cycle = function(pos, clicker)
 
 	local facing = minetest.get_node(pos).param2
 	local dir = minetest.facedir_to_dir(facing)
-	local controlling_coordinate = digtron.get_controlling_coordinate(pos, facing)
 
 	-- if the player is standing within the array or next to it, move him too.
 	local move_player = move_player_test(layout, clicker)
-	
+
 	-- test if any digtrons are obstructed by non-digtron nodes
 	layout:move_layout_image(dir)
 	if not layout:can_write_layout_image() then
@@ -453,12 +454,12 @@ digtron.execute_move_cycle = function(pos, clicker)
 	end
 
 	minetest.sound_play("truck", {gain=1.0, pos=pos})
-		
+
 	--move the array
 	if not layout:write_layout_image(clicker) then
 		return pos, "unrecoverable write_layout_image error", 1
 	end
-	
+
 	pos = vector.add(pos, dir)
 	if move_player then
 		clicker:moveto(vector.add(clicker:get_pos(), dir), true)
@@ -480,11 +481,12 @@ digtron.execute_downward_dig_cycle = function(pos, clicker)
 	local dir = digtron.facedir_to_down_dir(facing)
 	local fuel_burning = meta:get_float("fuel_burning") -- get amount of burned fuel left over from last cycle
 	local status_text = S("Heat remaining in controller furnace: @1", math.floor(math.max(0, fuel_burning)))
+	local return_code
 	local exhaust = meta:get_int("on_coal")
-	                                        
-	local layout = DigtronLayout.create(pos, clicker)
 
-	local status_text, return_code = neighbour_test(layout, status_text, dir)
+	local layout = digtron.DigtronLayout.create(pos, clicker)
+
+	status_text, return_code = neighbour_test(layout, status_text, dir)
 	if return_code ~= 0 then
 		return pos, status_text, return_code
 	end
@@ -494,21 +496,20 @@ digtron.execute_downward_dig_cycle = function(pos, clicker)
 		return pos, size_check_error, 8
 	end
 
-	
 	local controlling_coordinate = digtron.get_controlling_coordinate(pos, facing)
-	
+
 	----------------------------------------------------------------------------------------------------------------------
-	
+
 	local items_dropped = {}
 	local digging_fuel_cost = 0
 	local particle_systems = {}
-	
+
 	-- execute the execute_dig method on all digtron components that have one
 	-- This builds a set of nodes that will be dug and returns a list of products that will be generated
 	-- but doesn't actually dig the nodes yet. That comes later.
 	-- If we dug them now, sand would fall and some digtron nodes would die.
 	if layout.diggers ~= nil then
-		for k, location in pairs(layout.diggers) do
+		for _, location in pairs(layout.diggers) do
 			local target = minetest.get_node(location.pos)
 			local targetdef = minetest.registered_nodes[target.name]
 			if targetdef.execute_dig ~= nil then
@@ -527,9 +528,9 @@ digtron.execute_downward_dig_cycle = function(pos, clicker)
 			end
 		end
 	end
-	
+
 	----------------------------------------------------------------------------------------------------------------------
-	
+
 	-- test if any digtrons are obstructed by non-digtron nodes that haven't been marked
 	-- as having been dug.
 	local can_move = true
@@ -554,16 +555,16 @@ digtron.execute_downward_dig_cycle = function(pos, clicker)
 	end
 
 	----------------------------------------------------------------------------------------------------------------------
-	
+
 	-- All tests passed, ready to go for real!
 	minetest.sound_play("construction", {gain=1.0, pos=pos})
 
 	-- if the player is standing within the array or next to it, move him too.
 	local move_player = move_player_test(layout, clicker)
-	
+
 	-- damage the weak flesh
 	if digtron.config.damage_hp > 0 and layout.diggers ~= nil then
-		for k, location in pairs(layout.diggers) do
+		for _, location in pairs(layout.diggers) do
 			local target = minetest.get_node(location.pos)
 			local targetdef = minetest.registered_nodes[target.name]
 			if targetdef.damage_creatures ~= nil then
@@ -571,7 +572,7 @@ digtron.execute_downward_dig_cycle = function(pos, clicker)
 			end
 		end
 	end
-	
+
 	--move the array
 	layout:move_layout_image(digtron.facedir_to_down_dir(facing))
 	if not layout:write_layout_image(clicker) then
@@ -583,15 +584,15 @@ digtron.execute_downward_dig_cycle = function(pos, clicker)
 	if move_player then
 		clicker:moveto(vector.add(clicker:get_pos(), dir), true)
 	end
-	
+
 	-- store or drop the products of the digger heads
 	for _, itemname in pairs(items_dropped) do
 		digtron.place_in_inventory(itemname, layout.inventories, oldpos)
 	end
 	digtron.award_item_dug(items_dropped, clicker) -- Achievements mod hook
-	
-	local status_text = ""
-	
+
+	status_text = ""
+
 	-- actually burn the fuel needed
 	fuel_burning = fuel_burning - digging_fuel_cost
 	if digtron.config.particle_effects and exhaust == 1 then
@@ -614,13 +615,15 @@ digtron.execute_downward_dig_cycle = function(pos, clicker)
 	for _, particles in pairs(particle_systems) do
 		minetest.add_particlespawner(particles)
 	end
-	
+
 	-- finally, dig out any nodes remaining to be dug. Some of these will have had their flag revoked because
 	-- a builder put something there or because they're another digtron node.
 	local node_to_dig, whether_to_dig = layout.nodes_dug:pop()
 	while node_to_dig ~= nil do
 		if whether_to_dig == true then
-			minetest.log("action", string.format("%s uses Digtron to dig %s at (%d, %d, %d)", clicker:get_player_name(), minetest.get_node(node_to_dig).name, node_to_dig.x, node_to_dig.y, node_to_dig.z))
+			minetest.log("action", string.format(
+				"%s uses Digtron to dig %s at (%d, %d, %d)", clicker:get_player_name(), minetest.get_node(node_to_dig).name, node_to_dig.x, node_to_dig.y, node_to_dig.z)
+			)
 			minetest.remove_node(node_to_dig)
 		end
 		node_to_dig, whether_to_dig = layout.nodes_dug:pop()
diff --git a/util_item_place_node.lua b/util_item_place_node.lua
index ba6ff37..4a0fc12 100644
--- a/util_item_place_node.lua
+++ b/util_item_place_node.lua
@@ -36,13 +36,13 @@ digtron.whitelisted_on_place = function (item_name)
 	for listed_item, value in pairs(digtron.builder_on_place_items) do
 		if item_name == listed_item then return value end
 	end
-	
+
 	for prefix, value in pairs(digtron.builder_on_place_prefixes) do
 		if has_prefix(item_name, prefix) then return value end
 	end
-	
+
 	if minetest.get_item_group(item_name, "digtron_on_place") > 0 then return true end
-	
+
 	return false
 end
 
@@ -86,7 +86,7 @@ digtron.item_place_node = function(itemstack, placer, place_to, param2)
 	pointed_thing.type = "node"
 	pointed_thing.above = {x=place_to.x, y=place_to.y, z=place_to.z}
 	pointed_thing.under = {x=place_to.x, y=place_to.y - 1, z=place_to.z}
-	
+
 	-- Handle node-specific on_place calls as best we can.
 	if def.on_place and def.on_place ~= minetest.nodedef_default.on_place and digtron.whitelisted_on_place(item_name) then
 		if def.paramtype2 == "facedir" then
@@ -94,7 +94,7 @@ digtron.item_place_node = function(itemstack, placer, place_to, param2)
 		elseif def.paramtype2 == "wallmounted" then
 			pointed_thing.under = vector.add(place_to, minetest.wallmounted_to_dir(param2))
 		end
-	
+
 		-- pass a copy of the item stack parameter because on_place might modify it directly and then we can't tell if we succeeded or not
 		-- though note that some mods do "creative_mode" handling within their own on_place methods, which makes it impossible for Digtron
 		-- to know what to do in that case - if you're in creative_mode Digtron will place such items but it will think it failed and not
@@ -107,10 +107,10 @@ digtron.item_place_node = function(itemstack, placer, place_to, param2)
 			placed_node.param2 = param2
 			minetest.set_node(place_to, placed_node)
 		end
-		
+
 		return returnstack, success
 	end
-	
+
 	if minetest.registered_nodes[item_name] == nil then
 		-- Permitted craft items are handled by the node-specific on_place call, above.
 		-- if we are a craft item and we get here then we're not whitelisted and we should fail.
@@ -118,7 +118,7 @@ digtron.item_place_node = function(itemstack, placer, place_to, param2)
 		-- but this will protect us just in case.
 		return itemstack, false
 	end
-	
+
 	local oldnode = minetest.get_node_or_nil(place_to)
 
 	--this should never happen, digtron is testing for adjacent unloaded nodes before getting here.
@@ -141,7 +141,7 @@ digtron.item_place_node = function(itemstack, placer, place_to, param2)
 			" can not be placed at " .. minetest.pos_to_string(place_to))
 		return itemstack, false
 	end
-	
+
 	-- Add node and update
 	minetest.add_node(place_to, newnode)
 
@@ -162,7 +162,6 @@ digtron.item_place_node = function(itemstack, placer, place_to, param2)
 	-- Note that fake_player:update is called in the DigtronLayout class's "create" function,
 	-- which is called before Digtron does any of this building stuff, so it's not necessary
 	-- to update it here.
-	local _, callback
 	for _, callback in ipairs(minetest.registered_on_placenodes) do
 		-- Deepcopy pos, node and pointed_thing because callback can modify them
 		local place_to_copy = {x=place_to.x, y=place_to.y, z=place_to.z}