add `.luacheckrc` and gh action

.github/workflows/luacheck.yml

@@ -0,0 +1,17 @@
+name: luacheck
+
+on: [push, pull_request]
+
+jobs:
+  build:
+
+    runs-on: ubuntu-latest
+
+    steps:
+    - uses: actions/checkout@v2
+    - 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 ./

.luacheckrc

@@ -0,0 +1,30 @@
+
+globals = {
+	"mesecon",
+	"minetest"
+}
+
+-- ignore unused vars
+unused = false
+
+read_globals = {
+	-- Stdlib
+	string = {fields = {"split"}},
+	table = {fields = {"copy", "getn"}},
+
+	-- Minetest
+	"vector", "ItemStack",
+	"dump", "VoxelArea",
+
+	-- system
+	"DIR_DELIM",
+
+	-- deps
+	"default", "screwdriver"
+}
+
+ignore = {
+	"631", -- line too long
+	"621", -- inconsistent indendation
+	"542", -- empty if branch
+}

mesecons_microcontroller/init.lua

@@ -405,7 +405,7 @@ yc.command_print = function(params, eeprom, L)
 		if param:sub(1,1) == '"' and param:sub(#param, #param) == '"' then
 			s = s..param:sub(2, #param-1)
 		else
-			r = yc.command_parsecondition(param, L, eeprom)
+			local r = yc.command_parsecondition(param, L, eeprom)
 			if r == "1" or r == "0" then
 				s = s..r
 			else return nil end
@@ -543,12 +543,13 @@ yc.command_parsecondition = function(cond, L, eeprom)
 	cond = string.gsub(cond, "!0", "1")
 	cond = string.gsub(cond, "!1", "0")
 
-	local i = 2
-	local l = string.len(cond)
+	i = 2
+	l = string.len(cond)
 	while i<=l do
 		local s = cond:sub(i,i)
 		local b = tonumber(cond:sub(i-1, i-1))
 		local a = tonumber(cond:sub(i+1, i+1))
+		local buf
 		if cond:sub(i+1, i+1) == nil then break end
 		if s == "=" then
 			if a==nil then return nil end
@@ -562,8 +563,8 @@ yc.command_parsecondition = function(cond, L, eeprom)
 		i = i + 1
 	end
 
-	local i = 2
-	local l = string.len(cond)
+	i = 2
+	l = string.len(cond)
 	while i<=l do
 		local s = cond:sub(i,i)
 		local b = tonumber(cond:sub(i-1, i-1))

mesecons_pistons/init.lua

@@ -22,7 +22,7 @@ local function get_pistonspec_name(name, part)
 		return
 	end
 	for spec_name, spec in pairs(specs) do
-		for part, value in pairs(spec)  do
+		for _, value in pairs(spec)  do
 			if name == value then
 				return spec_name, part
 			end
@@ -462,8 +462,8 @@ end
 
 local function piston_get_stopper(node, dir, stack, stackid)
 	local pistonspec = get_pistonspec(node.name, "onname")
-	local dir = vector.multiply(minetest.facedir_to_dir(node.param2), -1)
-	local pusherpos = vector.add(stack[stackid].pos, dir)
+	local inverted_dir = vector.multiply(minetest.facedir_to_dir(node.param2), -1)
+	local pusherpos = vector.add(stack[stackid].pos, inverted_dir)
 	local pushernode = minetest.get_node(pusherpos)
 	if pistonspec.pusher == pushernode.name then
 		for _, s in ipairs(stack) do

mesecons_pressureplates/init.lua

@@ -50,8 +50,8 @@ function mesecon.register_pressure_plate(basename, description, textures_off, te
 	if not groups then
 		groups = {}
 	end
-	local groups_off = table.copy(groups)
-	local groups_on = table.copy(groups)
+	groups_off = table.copy(groups)
+	groups_on = table.copy(groups)
 	groups_on.not_in_creative_inventory = 1
 
 	mesecon.register_node(basename, {

mesecons_random/init.lua

@@ -59,7 +59,7 @@ minetest.register_node("mesecons_random:ghoststone_active", {
 	}},
 	on_construct = function(pos)
 		-- remove shadow
-		shadowpos = vector.add(pos, vector.new(0, 1, 0))
+		local shadowpos = vector.add(pos, vector.new(0, 1, 0))
 		if (minetest.get_node(shadowpos).name == "air") then
 			minetest.dig_node(shadowpos)
 		end