refactor: Address issues raised by linter

src/ftp.lua

@@ -56,7 +56,7 @@ end
 
 function metat.__index:login(user, password)
     self.try(self.tp:command("user", user or _M.USER))
-    local code, reply = self.try(self.tp:check{"2..", 331})
+    local code, _ = self.try(self.tp:check{"2..", 331})
     if code == 331 then
         self.try(self.tp:command("pass", password or _M.PASSWORD))
         self.try(self.tp:check("2.."))
@@ -66,7 +66,7 @@ end
 
 function metat.__index:pasv()
     self.try(self.tp:command("pasv"))
-    local code, reply = self.try(self.tp:check("2.."))
+    local _, reply = self.try(self.tp:check("2.."))
     local pattern = "(%d+)%D(%d+)%D(%d+)%D(%d+)%D(%d+)%D(%d+)"
     local a, b, c, d, p1, p2 = socket.skip(2, string.find(reply, pattern))
     self.try(a and b and c and d and p1 and p2, reply)
@@ -83,9 +83,9 @@ end
 
 function metat.__index:epsv()
     self.try(self.tp:command("epsv"))
-    local code, reply = self.try(self.tp:check("229"))
+    local _, reply = self.try(self.tp:check("229"))
     local pattern = "%((.)(.-)%1(.-)%1(.-)%1%)"
-    local d, prt, address, port = string.match(reply, pattern)
+    local _, _, _, port = string.match(reply, pattern)
     self.try(port, "invalid epsv response")
     self.pasvt = {
         address = self.tp:getpeername(),
@@ -102,7 +102,7 @@ end
 function metat.__index:port(address, port)
     self.pasvt = nil
     if not address then
-        address, port = self.try(self.tp:getsockname())
+        address = self.try(self.tp:getsockname())
         self.server = self.try(socket.bind(address, 0))
         address, port = self.try(self.server:getsockname())
         self.try(self.server:settimeout(_M.TIMEOUT))
@@ -118,7 +118,7 @@ end
 function metat.__index:eprt(family, address, port)
     self.pasvt = nil
     if not address then
-        address, port = self.try(self.tp:getsockname())
+        address = self.try(self.tp:getsockname())
         self.server = self.try(socket.bind(address, 0))
         address, port = self.try(self.server:getsockname())
         self.try(self.server:settimeout(_M.TIMEOUT))
@@ -142,7 +142,7 @@ function metat.__index:send(sendt)
     local command = sendt.command or "stor"
     -- send the transfer command and check the reply
     self.try(self.tp:command(command, argument))
-    local code, reply = self.try(self.tp:check{"2..", "1.."})
+    local code, _ = self.try(self.tp:check{"2..", "1.."})
     -- if there is not a pasvt table, then there is a server
     -- and we already sent a PORT command
     if not self.pasvt then self:portconnect() end

src/http.lua

@@ -41,9 +41,6 @@ local SCHEMES = {
             https.tcp, 'LuaSocket: Function tcp() not available from LuaSec')
           return tcp(t) end }}
 
--- default scheme and port for document retrieval
-local SCHEME = 'http'
-local PORT = SCHEMES[SCHEME].port
 -----------------------------------------------------------------------------
 -- Reads MIME headers from a connection, unfolding where needed
 -----------------------------------------------------------------------------
@@ -92,7 +89,7 @@ socket.sourcet["http-chunked"] = function(sock, headers)
             -- was it the last chunk?
             if size > 0 then
                 -- if not, get chunk and skip terminating CRLF
-                local chunk, err, part = sock:receive(size)
+                local chunk, err, _ = sock:receive(size)
                 if chunk then sock:receive() end
                 return chunk, err
             else
@@ -166,8 +163,8 @@ function metat.__index:receivestatusline()
     if status ~= "HTTP/" then
         if ec == "timeout" then
             return 408
-        end 
-        return nil, status 
+        end
+        return nil, status
     end
     -- otherwise proceed reading a status line
     status = self.try(self.c:receive("*l", status))
@@ -366,7 +363,7 @@ end
     local headers
     -- ignore any 100-continue messages
     while code == 100 do
-        headers = h:receiveheaders()
+        h:receiveheaders()
         code, status = h:receivestatusline()
     end
     headers = h:receiveheaders()

src/ltn12.lua

@@ -13,7 +13,7 @@ local unpack = unpack or table.unpack
 local base = _G
 local _M = {}
 if module then -- heuristic for exporting a global package table
-    ltn12 = _M
+    ltn12 = _M  -- luacheck: ignore
 end
 local filter,source,sink,pump = {},{},{},{}
 
@@ -23,7 +23,6 @@ _M.sink = sink
 _M.pump = pump
 
 local unpack = unpack or table.unpack
-local select = base.select
 
 -- 2048 seems to be better in windows...
 _M.BLOCKSIZE = 2048

src/mbox.lua

@@ -1,8 +1,8 @@
 local _M = {}
 
 if module then
-    mbox = _M
-end 
+    mbox = _M   -- luacheck: ignore
+end
 
 function _M.split_message(message_s)
     local message = {}
@@ -29,7 +29,7 @@ end
 function _M.parse_header(header_s)
     header_s = string.gsub(header_s, "\n[ ]+", " ")
     header_s = string.gsub(header_s, "\n+", "")
-    local _, __, name, value = string.find(header_s, "([^%s:]-):%s*(.*)")
+    local _, _, name, value = string.find(header_s, "([^%s:]-):%s*(.*)")
     return name, value
 end
 
@@ -49,9 +49,9 @@ function _M.parse_headers(headers_s)
 end
 
 function _M.parse_from(from)
-    local _, __, name, address = string.find(from, "^%s*(.-)%s*%<(.-)%>")
+    local _, _, name, address = string.find(from, "^%s*(.-)%s*%<(.-)%>")
     if not address then
-        _, __, address = string.find(from, "%s*(.+)%s*")
+        _, _, address = string.find(from, "%s*(.+)%s*")
     end
     name = name or ""
     address = address or ""
@@ -63,7 +63,8 @@ end
 function _M.split_mbox(mbox_s)
     local mbox = {}
     mbox_s = string.gsub(mbox_s, "\r\n", "\n") .."\n\nFrom \n"
-    local nj, i, j = 1, 1, 1
+    local nj, i
+    local j = 1
     while 1 do
         i, nj = string.find(mbox_s, "\n\nFrom .-\n", j)
         if not i then break end

src/mime.lua

@@ -10,7 +10,6 @@
 local base = _G
 local ltn12 = require("ltn12")
 local mime = require("mime.core")
-local string = require("string")
 local _M = mime
 
 -- encode, decode and wrap algorithm tables
@@ -18,7 +17,7 @@ local encodet, decodet, wrapt = {},{},{}
 
 _M.encodet = encodet
 _M.decodet = decodet
-_M.wrapt   = wrapt  
+_M.wrapt   = wrapt
 
 -- creates a function that chooses a filter by name from a given table
 local function choose(table)
@@ -27,7 +26,7 @@ local function choose(table)
             name, opt1, opt2 = "default", name, opt1
         end
         local f = table[name or "nil"]
-        if not f then 
+        if not f then
             base.error("unknown key (" .. base.tostring(name) .. ")", 3)
         else return f(opt1, opt2) end
     end
@@ -52,13 +51,6 @@ decodet['quoted-printable'] = function()
     return ltn12.filter.cycle(_M.unqp, "")
 end
 
-local function format(chunk)
-    if chunk then
-        if chunk == "" then return "''"
-        else return string.len(chunk) end
-    else return "nil" end
-end
-
 -- define the line-wrap filters
 wrapt['text'] = function(length)
     length = length or 76

src/url.lua

@@ -179,9 +179,9 @@ function _M.parse(url, default)
         function(u) parsed.userinfo = u; return "" end)
     authority = string.gsub(authority, ":([^:%]]*)$",
         function(p) parsed.port = p; return "" end)
-    if authority ~= "" then 
+    if authority ~= "" then
         -- IPv6?
-        parsed.host = string.match(authority, "^%[(.+)%]$") or authority 
+        parsed.host = string.match(authority, "^%[(.+)%]$") or authority
     end
     local userinfo = parsed.userinfo
     if not userinfo then return parsed end
@@ -264,7 +264,7 @@ function _M.absolute(base_url, relative_url)
                         relative_parsed.query = base_parsed.query
                     end
                 end
-            else    
+            else
                 relative_parsed.path = absolute_path(base_parsed.path or "",
                     relative_parsed.path)
             end