stricter luacheck

.luacheckrc

-unused_args = false
 allow_defined_top = true
 
 globals = {

gui.lua

@@ -43,7 +43,7 @@ function mail.show_inbox(name)
 	local messages = mail.getMessages(name)
 
 	if messages[1] then
-		for idx, message in ipairs(messages) do
+		for _, message in ipairs(messages) do
 			if message.unread then
 				formspec[#formspec + 1] = ",#FFD700"
 			else

util/channel.lua

@@ -65,7 +65,7 @@ local function Channel(http, url, cfg)
 			extra_headers = post_headers,
 			timeout = timeout,
 			post_data = minetest.write_json(data)
-		}, function(res)
+		}, function()
 			-- TODO: error-handling
 		end)
 	end