Try to fix most warnings reported by luacheck

.luacheckrc

@@ -0,0 +1,46 @@
+-- Disable some (non critical) warnings
+-- unused = false
+unused_args = false
+redefined = false
+
+globals = {
+	"airutils",
+}
+
+read_globals = {
+	"DIR_DELIM",
+	"ItemStack",
+	"PseudoRandom",
+	"basic_machines",
+	"biomass",
+	"climate_api",
+	"core",
+	"creative",
+	"default",
+	"dump",
+	"emote",
+	"math",
+	"mcl_formspec",
+	"mcl_player",
+	"minetest",
+	"player_api",
+	"signs_lib",
+	"skins",
+	"string",
+	"technic",
+	"vector",
+	"wardrobe",
+}
+
+-- Per file options
+files["airutils_biofuel.lua"] = {
+	globals = {"basic_machines.grinder_recipes"},
+}
+
+files["lib_planes/utilities.lua"] = {
+	globals = {"player_api.player_attached.?", "mcl_player.player_attached.?"}
+}
+
+files["pilot_skin_manager.lua"] = {
+	globals = {"skins.skin_class.apply_skin_to_player"}
+}

airutils_biofuel.lua

@@ -138,9 +138,6 @@ minetest.register_node( module_name .. ":biofuel_distiller", {
 			return 0
 		end
 
-		local meta = minetest.get_meta(pos)
-		local inv = meta:get_inventory()
-
 		if listname == "src" then
 			return stack:get_count()
 		elseif listname == "dst" then
@@ -154,10 +151,6 @@ minetest.register_node( module_name .. ":biofuel_distiller", {
 			return 0
 		end
 
-		local meta = minetest.get_meta(pos)
-		local inv = meta:get_inventory()
-		local stack = inv:get_stack(from_list, from_index)
-
 		if to_list == "src" then
 			return count
 		elseif to_list == "dst" then

airutils_papi.lua

@@ -19,7 +19,6 @@ function airutils.PAPIplace(player,pos)
     end
 
 	local dir = minetest.dir_to_facedir(player:get_look_dir())
-	local pos1 = vector.new(pos)
 
     local player_name = player:get_player_name()
 	if check_protection(pos, player_name) then
@@ -107,11 +106,6 @@ minetest.register_node("airutils:papi",{
 		        return
             end
 	    end
-
-        local itmstck=puncher:get_wielded_item()
-        local item_name = ""
-        if itmstck then item_name = itmstck:get_name() end
-
     end,
 })
 
@@ -161,11 +155,6 @@ minetest.register_node("airutils:papi_right",{
 	    if player_name ~= meta:get_string("owner") then
 		    return
 	    end
-
-        local itmstck=puncher:get_wielded_item()
-        local item_name = ""
-        if itmstck then item_name = itmstck:get_name() end
-
     end,
 })
 

airutils_tug.lua

@@ -50,8 +50,7 @@ minetest.register_tool("airutils:tug", {
 			return
 		end
 
-        local is_admin = false
+        local is_admin = minetest.check_player_privs(player, {server=true})
-        is_admin = minetest.check_player_privs(player, {server=true})            
 
         local pos = player:get_pos()
         local pname = player:get_player_name()

airutils_wind.lua

@@ -47,7 +47,7 @@ airutils.wind_selection_box = {
 local function get_smooth(angle_initial, reference, last_ref, value)
     local range = reference-last_ref
     local retVal = (value*angle_initial)/range
-    retval = angle_initial - retVal
+    local retval = angle_initial - retVal
     if retval < 0 then retval = 0 end
     return retval
 end
@@ -115,12 +115,11 @@ minetest.register_entity("airutils:wind_indicator",{
 	end,
 
     on_rightclick = function(self, clicker)
-        local wind = airutils.get_wind(pos, 2.0)
+        local wind = airutils.get_wind(self.object:get_pos(), 2.0)
         local wind_yaw = minetest.dir_to_yaw(wind)
         minetest.chat_send_player(clicker:get_player_name(),core.colorize('#00ff00', S(" >>> The wind direction now is @1", math.deg(wind_yaw))))
 		return
     end,
-                                            
 })
 
 
@@ -156,7 +155,6 @@ minetest.register_node("airutils:wind",{
 			if not minetest.is_protected(pos, player_name) and not minetest.is_protected(pos, player_name) then
 				minetest.set_node(pos, {name = "airutils:wind",param2 = 1 })
 				minetest.add_entity({x=pos.x, y=pos.y, z=pos.z},"airutils:wind_indicator")
-				local meta = minetest.get_meta(pos)
 				if not (creative and creative.is_enabled_for and creative.is_enabled_for(player_name)) then
 					itemstack:take_item()
 				end

attach_extern_ent.lua

@@ -29,7 +29,6 @@ function airutils.get_attached_entity(self)
     if not self._vehicle_custom_data then return nil, nil end
     if not self._vehicle_custom_data.simple_external_attach_entity then return nil, nil end
 
-    local entity_name = self._vehicle_custom_data.simple_external_attach_entity
     local inv_id = self._vehicle_custom_data.simple_external_attach_invid
 
     local pos = self.object:get_pos()
@@ -85,7 +84,7 @@ function airutils.simple_external_attach(self, relative_pos, entity_name, radius
     attach_up = attach_up or false
     radius = radius or 12
     if self.object then
-        local curr_ent, curr_obj = airutils.get_attached_entity(self)
+        local curr_ent, _ = airutils.get_attached_entity(self)
         if curr_ent then return end
 
         local pos = self.object:get_pos()
@@ -112,7 +111,6 @@ function airutils.restore_external_attach(self)
 
     local pos = self.object:get_pos()
     local dest_pos = vector.new(pos)
-    local entity_name = self._vehicle_custom_data.simple_external_attach_entity
     local relative_pos = self._vehicle_custom_data.simple_external_attach_pos
     local inv_id = self._vehicle_custom_data.simple_external_attach_invid
     dest_pos = vector.add(dest_pos, relative_pos)
@@ -126,7 +124,7 @@ function airutils.restore_external_attach(self)
                 --minetest.chat_send_all(dump(ent.name))
                 if ent._inv_id then
                     --minetest.chat_send_all(">> "..dump(ent._inv_id).." >> "..dump(inv_id))
-                    if ent._inv_id == inv_id and (not (ent._inv_id == self._inv_id)) then
+                    if ent._inv_id == inv_id and ent._inv_id ~= self._inv_id then
                         --minetest.chat_send_all("++ "..dump(ent._inv_id).." ++ "..dump(inv_id))
                         local target_obj = nearby_objects[i]
                         target_obj:set_pos(dest_pos)

init.lua

@@ -300,15 +300,6 @@ end
 -- max_height: the max ceilling for the airplane
 -- wingspan: for ground effect calculation
 function airutils.getLiftAccel(self, velocity, accel, longit_speed, roll, curr_pos, in_lift, max_height, wingspan)
-    local new_velocity = vector.new(velocity)
-    if not self._min_collective then --ignore if it is an helicopter
-        --add wind to the lift calcs
-        local wind = airutils.get_wind(curr_pos, 5)
-        local accel_wind = vector.subtract(accel, wind)  --why? because I need to fake more speed when against the wind to gain lift
-        local vel_wind = vector.multiply(accel_wind, self.dtime)
-        new_velocity = vector.add(new_velocity, vel_wind)
-    end
-
     if longit_speed == nil then longit_speed = 0 end
     wingspan = wingspan or 10
     local lift = in_lift
@@ -439,7 +430,7 @@ function airutils.set_paint(self, puncher, itmstck, texture_name)
     else
         --painting with dyes
         local split = string.split(item_name, ":")
-        local color, indx, _
+        local indx, _
         if split[1] then _,indx = split[1]:find('dye') end
         if indx then
             --[[for clr,_ in pairs(airutils.colors) do
@@ -469,7 +460,7 @@ function airutils._set_name(self)
     if not airutils._use_signs_api then return end
     local l_textures = self.object:get_properties().textures   --self.initial_properties.textures
     for _, texture in ipairs(l_textures) do
-        indx = texture:find('airutils_name_canvas.png')
+        local indx = texture:find('airutils_name_canvas.png')
         if indx then
             l_textures[_] = "airutils_name_canvas.png^"..airutils.convert_text_to_texture(self._ship_name, self._name_color or 0, self._name_hor_aligment or 0.8)
         end
@@ -606,7 +597,6 @@ minetest.register_chatcommand("ground_effect", {
     description = S("Enables/disables the ground effect (for debug purposes)"),
     privs = {server=true},
 	func = function(name, param)
-        local player = minetest.get_player_by_name(name)
         if minetest.check_player_privs(name, {server=true}) then
             if param == "on" or param == "" then
                 airutils.ground_effect_is_disabled = nil
@@ -626,7 +616,6 @@ minetest.register_chatcommand("show_lift", {
     description = S("Enables/disables the lift printing (for debug purposes)"),
     privs = {server=true},
 	func = function(name, param)
-        local player = minetest.get_player_by_name(name)
         if minetest.check_player_privs(name, {server=true}) then
             if param == "on" or param == "" then
                 airutils.show_lift = name

lib_copter/control.lua

@@ -4,29 +4,6 @@ local S = airutils.S
 
 dofile(minetest.get_modpath("airutils") .. DIR_DELIM .. "lib_planes" .. DIR_DELIM .. "utilities.lua")
 
-local function floating_auto_correction(self, dtime)
-    local factor = 1
-    local range = 0.03 --above and bellow
-
-    if self._wing_configuration > self._stable_collective + range or
-        self._wing_configuration < self._stable_collective - range then
-        return
-    end
-
-    --minetest.chat_send_player(self.driver_name, "antes: " .. self._air_float)
-    if self._wing_configuration > self._stable_collective then factor = -1 end
-    local time_correction = (dtime/airutils.ideal_step)
-    if time_correction < 1 then time_correction = 1 end
-    local intensity = 1
-    local correction = (intensity*factor) * time_correction
-
-    local new_wing_configuration = self._wing_configuration + correction
-
-    self._wing_configuration = new_wing_configuration
-
-    --minetest.chat_send_all(dump(self._wing_configuration))
-end
-
 local function set_yaw_by_mouse(self, dir)
     local rotation = self.object:get_rotation()
     local rot_y = math.deg(rotation.y)
@@ -62,7 +39,7 @@ function airutils.heli_control(self, dtime, hull_direction, longit_speed, longit
     local retval_accel = accel
 
     local stop = false
-    local ctrl = nil
+    local ctrl
 
     local time_correction = (dtime/airutils.ideal_step)
     if time_correction < 1 then time_correction = 1 end
@@ -80,10 +57,6 @@ function airutils.heli_control(self, dtime, hull_direction, longit_speed, longit
         if not self._lat_acceleration then self._lat_acceleration = 0 end
 
         if self._engine_running then
-            --engine acceleration calc
-
-            local factor = 1
-
             --control lift
             local collective_up_max = 1.2
             local min_angle = self._min_collective

lib_copter/entities.lua

@@ -1,6 +1,6 @@
 dofile(minetest.get_modpath("airutils") .. DIR_DELIM .. "lib_planes" .. DIR_DELIM .. "global_definitions.lua")
 
-function engineSoundPlay(self, increment, base)
+local function engineSoundPlay(self, increment, base)
     increment = increment or 0.0
     --sound
     if self.sound_handle then minetest.sound_stop(self.sound_handle) end
@@ -24,7 +24,7 @@ local function engine_set_sound_and_animation(self, is_flying, newpitch, newroll
         end
         --self._cmd_snd
         if self._snd_last_cmd ~= self._cmd_snd then
-            local increment = 0.0
+            local increment
             self._snd_last_cmd = self._cmd_snd
             if self._cmd_snd then increment = 0.1 else increment = 0.0 end
             engineSoundPlay(self, increment, 0.9)
@@ -34,7 +34,7 @@ local function engine_set_sound_and_animation(self, is_flying, newpitch, newroll
     else
         if is_flying then --autorotation here
             if self._snd_last_cmd ~= self._cmd_snd then
-                local increment = 0.0
+                local increment
                 self._snd_last_cmd = self._cmd_snd
                 if self._cmd_snd then increment = 0.1 else increment = 0.0 end
                 engineSoundPlay(self, increment, 0.6)
@@ -100,7 +100,6 @@ function airutils.logic_heli(self)
     local rotation = self.object:get_rotation()
     local yaw = rotation.y
 	local newyaw=yaw
-    local pitch = rotation.x
 	local roll = rotation.z
 
     local hull_direction = airutils.rot_to_dir(rotation) --minetest.yaw_to_dir(yaw)
@@ -118,7 +117,6 @@ function airutils.logic_heli(self)
     local accel = vector.add(longit_drag,later_drag)
     local stop = false
 
-    local node_bellow = airutils.nodeatpos(airutils.pos_shift(curr_pos,{y=-1.3}))
     local is_flying = true
     if self.colinfo then
         is_flying = (not self.colinfo.touching_ground)
@@ -290,7 +288,7 @@ function airutils.logic_heli(self)
         self._last_accell = new_accel
 	    self.object:move_to(curr_pos)
         --airutils.set_acceleration(self.object, new_accel)
-        local limit = self._climb_speed
+        --local limit = self._climb_speed
         --if new_accel.y > limit then new_accel.y = limit end --it isn't a rocket :/
 
     else

lib_planes/control.lua

@@ -11,7 +11,6 @@ function airutils.powerAdjust(self,dtime,factor,dir,max_power)
     local max = max_power or 100
     local add_factor = factor/2
     add_factor = add_factor * (dtime/airutils.ideal_step) --adjusting the command speed by dtime
-    local power_index = self._power_lever
 
     if dir == 1 then
         if self._power_lever < max then
@@ -150,8 +149,7 @@ function airutils.control(self, dtime, hull_direction, longit_speed, longit_drag
 
     if longit_speed > 0 then
         if ctrl then
-            if ctrl.right or ctrl.left then
+            if not (ctrl.right or ctrl.left) then
-            else
                 airutils.rudder_auto_correction(self, longit_speed, dtime)
             end
         else
@@ -178,11 +176,9 @@ function airutils.set_pitch(self, dir, dtime)
     local multiplier = pitch_factor*(dtime/airutils.ideal_step)
 	if dir == -1 then
         --minetest.chat_send_all("cabrando")
-        if self._elevator_angle > 0 then pitch_factor = pitch_factor * 2 end
 		self._elevator_angle = math.max(self._elevator_angle-multiplier,-self._elevator_limit)
 	elseif dir == 1 then
         --minetest.chat_send_all("picando")
-        if self._angle_of_attack < 0 then pitch_factor = 1 end --lets reduce the command power to avoid accidents
 		self._elevator_angle = math.min(self._elevator_angle+multiplier,self._elevator_limit)
 	end
 end
@@ -192,11 +188,9 @@ function airutils.set_autopilot_pitch(self, dir, dtime)
     local multiplier = pitch_factor*(dtime/airutils.ideal_step)
 	if dir == -1 then
         --minetest.chat_send_all("cabrando")
-        if self._elevator_angle > 0 then pitch_factor = pitch_factor * 2 end
 		self._elevator_angle = math.max(self._elevator_angle-multiplier,-self._elevator_limit)
 	elseif dir == 1 then
         --minetest.chat_send_all("picando")
-        if self._angle_of_attack < 0 then pitch_factor = 1 end --lets reduce the command power to avoid accidents
 		self._elevator_angle = math.min(self._elevator_angle+multiplier,self._elevator_limit)
 	end
 end
@@ -243,22 +237,12 @@ function airutils.rudder_auto_correction(self, longit_speed, dtime)
     end
 end
 
---obsolete, will be removed
-function getAdjustFactor(curr_y, desired_y)
-    local max_difference = 0.1
-    local adjust_factor = 0.5
-    local difference = math.abs(curr_y - desired_y)
-    if difference > max_difference then difference = max_difference end
-    return (difference * adjust_factor) / max_difference
-end
-
 function airutils.autopilot(self, dtime, hull_direction, longit_speed, accel, curr_pos)
 
     local retval_accel = accel
 
     if not self._have_auto_pilot then return end
 
-    local max_autopilot_power = 85
     local max_attack_angle = 1.8
 
     --climb

lib_planes/custom_physics.lua

@@ -30,7 +30,6 @@ function airutils.physics(self)
     end
 
     if self.isinliquid then
-        local accell = {x=0, y=0, z=0}
         self.water_drag = 0.2
         self.isinliquid = true
         local height = self.height
@@ -38,7 +37,7 @@ function airutils.physics(self)
 --		local balance = self.buoyancy*self.height
         local buoyacc = airutils.gravity*(self.buoyancy-submergence)
         --local buoyacc = self._baloon_buoyancy*(self.buoyancy-submergence)
-        accell = {
+        local accell = {
                     x=-vel.x*self.water_drag,
                     y=buoyacc-(vel.y*math.abs(vel.y)*0.4),
                     z=-vel.z*self.water_drag

lib_planes/entities.lua

@@ -280,7 +280,6 @@ function airutils.logic(self)
     local rotation = self.object:get_rotation()
     local yaw = rotation.y
 	local newyaw=yaw
-    local pitch = rotation.x
 	local roll = rotation.z
 	local newroll=roll
     newroll = math.floor(newroll/360)
@@ -411,11 +410,12 @@ function airutils.logic(self)
 
     --is an stall, force a recover
     if longit_speed < (self._min_speed+0.5) and climb_rate < -1.5 and is_flying then
+        --[[
         if player and self.driver_name then
-            --minetest.chat_send_player(self.driver_name,core.colorize('#ff0000', " >>> STALL"))
+            minetest.chat_send_player(self.driver_name,core.colorize('#ff0000', " >>> STALL"))
         end
+        ]]--
         self._elevator_angle = 0
-        actuator_angle = 0
         self._angle_of_attack = -1
         newpitch = math.rad(self._angle_of_attack)
     else
@@ -516,7 +516,7 @@ function airutils.logic(self)
     --end accell
 
     --get disconnected players
-    if not self._autoflymode == true then
+    if self._autoflymode ~= true then
         airutils.rescueConnectionFailedPassengers(self)
     end
 
@@ -732,8 +732,7 @@ function airutils.on_punch(self, puncher, ttime, toolcaps, dir, damage)
             damage_vehicle(self, toolcaps, ttime, damage)
     end
 
-    local is_admin = false
+    local is_admin = minetest.check_player_privs(puncher, {server=true})
-    is_admin = minetest.check_player_privs(puncher, {server=true})
     if self.owner == nil then
         self.owner = name
     end
@@ -831,9 +830,9 @@ local function get_vehicle(self, player)
         local lua_ent = self.object:get_luaentity()
         local staticdata = lua_ent:get_staticdata(self)
         local obj_name = lua_ent.name
+        local pos = self.object:get_pos()
 
         local stack = ItemStack(obj_name)
-        local max = stack:get_stack_max()
         local tool = false
         if stack:get_stack_max() == 1 then tool = true end
 
@@ -886,8 +885,6 @@ function airutils.on_rightclick(self, clicker)
 
     --minetest.chat_send_all(dump(self.driver_name))
 
-    local touching_ground, liquid_below = airutils.check_node_below(self.object, 2.5)
-    local is_on_ground = self.isinliquid or touching_ground or liquid_below
     local is_under_water = airutils.check_is_under_water(self.object)
 
     --minetest.chat_send_all('name '.. dump(name) .. ' - pilot: ' .. dump(self.driver_name) .. ' - pax: ' .. dump(copilot_name))
@@ -946,8 +943,6 @@ function airutils.on_rightclick(self, clicker)
         if self.owner == name or minetest.check_player_privs(clicker, {protection_bypass=true}) then
 
             local itmstck=clicker:get_wielded_item()
-            local item_name = ""
-            if itmstck then item_name = itmstck:get_name() end
 
 	        if itmstck then
 		        if airutils.set_param_paint(self, clicker, itmstck, 2) == true then

lib_planes/forms.lua

@@ -168,8 +168,6 @@ function airutils.adf_formspec(name)
                 z = math.floor(ent._adf_destiny.z)
             end
         end
-    else
-        --return
     end
 
     local basic_form = table.concat({
@@ -280,7 +278,7 @@ minetest.register_on_player_receive_fields(function(player, formname, fields)
                 airutils.attach_pax(ent, player)
 		    end
 		    if fields.go_out then
-                local touching_ground, liquid_below = airutils.check_node_below(plane_obj, 2.5)
+                local touching_ground, _ = airutils.check_node_below(plane_obj, 2.5)
                 if ent.isinliquid or touching_ground then --isn't flying?
                     airutils.dettach_pax(ent, player)
                 else
@@ -308,12 +306,11 @@ minetest.register_on_player_receive_fields(function(player, formname, fields)
 		    if fields.go_out then
                 local touch_point = ent.initial_properties.collisionbox[2]-1.0
                 -----////
-                local is_on_ground = false
                 local pos = plane_obj:get_pos()
                 pos.y = pos.y + touch_point
                 local node_below = minetest.get_node(pos).name
                 local nodedef = minetest.registered_nodes[node_below]
-                is_on_ground = not nodedef or nodedef.walkable or false -- unknown nodes are solid
+                local is_on_ground = not nodedef or nodedef.walkable or false -- unknown nodes are solid
 
                 if ent.driver_name == name and ent.owner == ent.driver_name then --just the owner can do this
                     --minetest.chat_send_all(dump(noded))

lib_planes/fuel_management.lua

@@ -25,7 +25,7 @@ function airutils.loadFuel(self, player_name)
             self._energy = self._energy + fuel
             if self._energy > self._max_fuel then self._energy = self._max_fuel end
 
-            local energy_indicator_angle = airutils.get_gauge_angle(self._energy)
+            --local energy_indicator_angle = airutils.get_gauge_angle(self._energy)
             --self.fuel_gauge:set_attach(self.object,'',self._gauge_fuel_position,{x=0,y=0,z=energy_indicator_angle})
         end
 

lib_planes/gauges.lua

@@ -1,9 +1,10 @@
+--[[
 local function get_pointer(pointer_angle, gauge_center_x, gauge_center_y, full_pointer)
     full_pointer = full_pointer or 1
     local retval = ""
     local ind_pixel = "airutils_ind_box_2.png"
 
-    pointer_img_size = 8
+    local pointer_img_size = 8
     local pointer_rad = math.rad(pointer_angle)
     local dim = 2*(pointer_img_size/2)
     local pos_x = math.sin(pointer_rad) * dim
@@ -33,6 +34,7 @@ local function get_pointer(pointer_angle, gauge_center_x, gauge_center_y, full_p
     end
     return retval
 end
+]]--
 
 function airutils.plot_altimeter_gauge(self, scale, place_x, place_y)
     local bg_width_height = 100

lib_planes/init.lua

@@ -17,11 +17,3 @@ dofile(minetest.get_modpath("airutils") .. DIR_DELIM .. "lib_planes" .. DIR_DELI
 --
 -- items
 --
-
-settings = Settings(minetest.get_worldpath() .. "/settings.conf")
-local function fetch_setting(name)
-    local sname = name
-    return settings and settings:get(sname) or minetest.settings:get(sname)
-end
-
-

lib_planes/utilities.lua

@@ -535,7 +535,6 @@ function airutils.testImpact(self, velocity, position)
             }, true)
             self.hp_max = self.hp_max - self._damage_by_wind_speed
             if self.driver_name then
-                local player_name = self.driver_name
                 airutils.setText(self, self._vehicle_name)
             end
             if self.hp_max < 0 then --if acumulated damage is greater than 50, adieu
@@ -751,7 +750,7 @@ function airutils.set_param_paint(self, puncher, itmstck, mode)
     else
         --painting with dyes
         local split = string.split(item_name, ":")
-        local color, indx, _
+        local indx, _
         if split[1] then _,indx = split[1]:find('dye') end
         if indx then
             self._skin = ""
@@ -879,7 +878,7 @@ end
 function airutils.paint_with_mask(self, colstr, target_texture, mask_texture)
     if colstr then
         self._color = colstr
-        self._det_color = mask_colstr
+        self._det_color = mask_colstr -- !!! accessing undefined variable mask_colstr
         local l_textures = self.initial_properties.textures
         for _, texture in ipairs(l_textures) do
             local indx = texture:find(target_texture)
@@ -904,7 +903,7 @@ function airutils.pid_controller(current_value, setpoint, last_error, d_time, kp
     local _error = setpoint - current_value
     local derivative = _error - last_error
     --local output = kpv*erro + (kpv/Tiv)*I + kpv*Tdv*((erro - erro_passado)/delta_t);
-    if integrative == nil then integrative = 0 end
+    if integrative == nil then integrative = 0 end -- !!! accessing undefined variable integrative
     integrative = integrative + (((_error + last_error)/delta_t)/2);
     local output = kp*_error + (kp/ti)*integrative + kp * td*((_error - last_error)/delta_t)
     last_error = _error
@@ -927,7 +926,6 @@ function airutils.add_smoke_trail(self, smoke_type)
     end
 
     if self._smoke_spawner == nil then
-        local radius = 1
 	    self._smoke_spawner = minetest.add_particlespawner({
 		    amount = 3,
 		    time = 0,
@@ -1044,7 +1042,7 @@ function airutils.add_blast_damage(pos, radius, damage_cal)
                     }, nil)
 				end
 				for _, item in pairs(entity_drops) do
-					add_drop(drops, item)
+					add_drop(drops, item) -- !!! accessing undefined variable add_drop, drops
 				end
 			end
 
@@ -1179,7 +1177,6 @@ end
 
 function airutils.seats_update(self)
     if self.object then
-        local pos = self.object:get_pos()
         if self._passengers_base then
             local max_seats = table.getn(self._passengers_base)
             for i=1, max_seats do
@@ -1324,8 +1321,6 @@ function airutils.destroyed_save_static_data(self)
 end
 
 function airutils.destroyed_on_activate(self, staticdata, dtime_s)
-    local pos = self.object:get_pos()
-
     if staticdata ~= "" and staticdata ~= nil then
         local data = minetest.deserialize(staticdata) or {}
         self.owner = data.stored_owner
@@ -1354,7 +1349,6 @@ local function check_shared_by_time(self)
 end
 
 function airutils.destroyed_open_inventory(self, clicker)
-    local message = ""
 	if not clicker or not clicker:is_player() then
 		return
 	end
@@ -1386,8 +1380,7 @@ function airutils.destroyed_on_punch(self, puncher, ttime, toolcaps, dir, damage
     local shared_by_time = check_shared_by_time(self)
     local pos = self.object:get_pos()
 
-    local is_admin = false
+    local is_admin = minetest.check_player_privs(puncher, {server=true})
-    is_admin = minetest.check_player_privs(puncher, {server=true})
     if shared_by_time == false then
         if self.owner and self.owner ~= name and self.owner ~= "" then
             if is_admin == false then return end

physics_lib.lua

@@ -174,7 +174,7 @@ function airutils.stepfunc(self,dtime,colinfo)
 	if self.logic then
 		if self.view_range then self:sensefunc() end
 		self:logic()
-		execute_queues(self)
+		execute_queues(self) -- !!! accessing undefined variable execute_queues
 	end
 
 	self.lastvelocity = self.object:get_velocity()

pilot_skin_manager.lua

@@ -3,8 +3,6 @@ local S = airutils.S
 airutils.pilot_textures = {"pilot_clothes1.png","pilot_clothes2.png","pilot_clothes3.png","pilot_clothes4.png",
         "pilot_novaskin_girl.png","pilot_novaskin_girl_steampunk.png","pilot_novaskin_girl_2.png","pilot_novaskin_girl_steampunk_2.png"}
 local skinsdb_mod_path = minetest.get_modpath("skinsdb")
-local backup = "airutils:bcp_last_skin"
-local curr_skin = "airutils:skin"
 
 minetest.register_chatcommand("au_uniform", {
     func = function(name, param)
@@ -99,7 +97,7 @@ function airutils.set_player_skin(player, skin)
         else
             --remove texture
             local old_texture = player_meta:get_string("backup")
-            if set_skin then
+            if set_skin then -- !!! accessing undefined variable set_skin
                 if player:get_attribute("set_skin:player_skin") ~= nil and player:get_attribute("set_skin:player_skin") ~= "" then
                     old_texture = player:get_attribute("set_skin:player_skin")
                 end

text.lua

@@ -58,7 +58,7 @@ local function clamp_characters(text, max_lenght)
     local c = ""
     for i = 1, #new_string, 1 do
         c = string.sub(new_string,i,i)
-        if not (c == control_char) then
+        if c ~= control_char then
             count = count + 1
         end
         curr_index = i
@@ -71,7 +71,7 @@ local function clamp_characters(text, max_lenght)
     local control_order_curr_intex = 0
     for i = 1, #cutstring, 1 do
         c = string.sub(cutstring,i,i)
-        if not (c == control_char) then
+        if c ~= control_char then
             outputstring = outputstring .. (c or "")
         else
             control_order_curr_intex = control_order_curr_intex + 1

texture_management.lua

@@ -48,7 +48,7 @@ local function getTexturesFromItem(itemDef)
 end
 
 --function to remove duplicates and invalid for textlist
-function filter_texture_names(list_to_test)
+local function filter_texture_names(list_to_test)
     local hash = {}
     local result = {}
     for _,v in ipairs(list_to_test) do
@@ -63,7 +63,7 @@ function filter_texture_names(list_to_test)
 end
 
 -- Function to list all loaded textures
-function listLoadedTextures()
+local function listLoadedTextures()
     local loadedTextures = {}
 
     --nodes