Lint bios and the rom (#321)

We now use illuaminate[1]'s linting facilities to check the rom and
bios.lua for a couple of common bugs and other problems.

Right now this doesn't detect any especially important bugs, though it
has caught lots of small things (unused variables, some noisy code). In
the future, the linter will grow in scope and features, which should
allow us to be stricter and catch most issues.

As a fun aside, we started off with ~150 bugs, and illuaminate was able
to fix all but 30 of them, which is pretty neat.

[1]: https://github.com/SquidDev/illuaminate

.editorconfig

@@ -11,5 +11,8 @@ insert_final_newline = true
 [*.md]
 trim_trailing_whitespace = false
 
+[*.sexp]
+indent_size = 2
+
 [*.properties]
 insert_final_newline = false

.github/workflows/main-ci.yml

@@ -4,6 +4,7 @@ on: [push, pull_request]
 
 jobs:
   build:
+    name: Build
     runs-on: ubuntu-latest
 
     steps:
@@ -16,3 +17,17 @@ jobs:
 
     - name: Build with Gradle
       run: ./gradlew build --no-daemon
+
+  lint-lua:
+    name: Lint Lua
+    runs-on: ubuntu-latest
+
+    steps:
+    - uses: actions/checkout@v1
+
+    - name: Lint Lua code
+      run: |
+        test -d bin || mkdir bin
+        test -f bin/illuaminate || wget -q -Obin/illuaminate https://squiddev.cc/illuaminate/bin/illuaminate
+        chmod +x bin/illuaminate
+        GITHUB_TOKEN=${{ secrets.GITHUB_TOKEN }} bin/illuaminate lint --github

illuaminate.sexp

@@ -0,0 +1,25 @@
+; -*- mode: Lisp;-*-
+
+(sources
+  /src/main/resources/assets/computercraft/lua/bios.lua
+  /src/main/resources/assets/computercraft/lua/rom/)
+
+(at /
+  (linters
+    ;; It'd be nice to avoid this, but right now there's a lot of instances of it.
+    -var:set-loop
+
+    ;; It's useful to name arguments for documentation, so we allow this. It'd
+    ;; be good to find a compromise in the future, but this works for now.
+    -var:unused-arg))
+
+;; We disable the two global linters in bios.lua and the APIs. In the future
+;; hopefully we'll get illuaminate to handle this.
+(at
+  (/src/main/resources/assets/computercraft/lua/bios.lua
+   /src/main/resources/assets/computercraft/lua/rom/apis/)
+  (linters -var:set-global -var:unused-global))
+
+;; These warnings are broken right now
+(at completion.lua (linters -doc:malformed-type))
+(at (bios.lua worm.lua) (linters -control:unreachable))

src/main/resources/assets/computercraft/lua/bios.lua

@@ -184,7 +184,7 @@ function sleep( nTime )
     expect(1, nTime, "number", "nil")
     local timer = os.startTimer( nTime or 0 )
     repeat
-        local sEvent, param = os.pullEvent( "timer" )
+        local _, param = os.pullEvent( "timer" )
     until param == timer
 end
 
@@ -233,7 +233,7 @@ function write( sText )
                         newLine()
                     end
                     term.write( text )
-                    text = string.sub( text, (w-x) + 2 )
+                    text = string.sub( text, w-x + 2 )
                     x,y = term.getCursorPos()
                 end
             else
@@ -332,7 +332,7 @@ function read( _sReplaceChar, _tHistory, _fnComplete, _sDefault )
 
         local _, cy = term.getCursorPos()
         term.setCursorPos( sx, cy )
-        local sReplace = (_bClear and " ") or _sReplaceChar
+        local sReplace = _bClear and " " or _sReplaceChar
         if sReplace then
             term.write( string.rep( sReplace, math.max( #sLine - nScroll, 0 ) ) )
         else
@@ -544,7 +544,7 @@ function read( _sReplaceChar, _tHistory, _fnComplete, _sDefault )
         end
     end
 
-    local cx, cy = term.getCursorPos()
+    local _, cy = term.getCursorPos()
     term.setCursorBlink( false )
     term.setCursorPos( w + 1, cy )
     print()
@@ -775,7 +775,7 @@ if http then
         if not ok then return ok, err end
 
         while true do
-            local event, url, ok, err = os.pullEvent( "http_check" )
+            local _, url, ok, err = os.pullEvent( "http_check" )
             if url == _url then return ok, err end
         end
     end
@@ -808,8 +808,8 @@ function fs.complete( sPath, sLocation, bIncludeFiles, bIncludeDirs )
     expect(3, bIncludeFiles, "boolean", "nil")
     expect(4, bIncludeDirs, "boolean", "nil")
 
-    bIncludeFiles = (bIncludeFiles ~= false)
+    bIncludeFiles = bIncludeFiles ~= false
-    bIncludeDirs = (bIncludeDirs ~= false)
+    bIncludeDirs = bIncludeDirs ~= false
     local sDir = sLocation
     local nStart = 1
     local nSlash = string.find( sPath, "[/\\]", nStart )
@@ -836,9 +836,9 @@ function fs.complete( sPath, sLocation, bIncludeFiles, bIncludeDirs )
         end
         if sDir ~= "" then
             if sPath == "" then
-                table.insert( tResults, (bIncludeDirs and "..") or "../" )
+                table.insert( tResults, bIncludeDirs and ".." or "../" )
             elseif sPath == "." then
-                table.insert( tResults, (bIncludeDirs and ".") or "./" )
+                table.insert( tResults, bIncludeDirs and "." or "./" )
             end
         end
         local tFiles = fs.list( sDir )
@@ -867,7 +867,7 @@ end
 -- Load APIs
 local bAPIError = false
 local tApis = fs.list( "rom/apis" )
-for n,sFile in ipairs( tApis ) do
+for _,sFile in ipairs( tApis ) do
     if string.sub( sFile, 1, 1 ) ~= "." then
         local sPath = fs.combine( "rom/apis", sFile )
         if not fs.isDir( sPath ) then
@@ -881,7 +881,7 @@ end
 if turtle and fs.isDir( "rom/apis/turtle" ) then
     -- Load turtle APIs
     local tApis = fs.list( "rom/apis/turtle" )
-    for n,sFile in ipairs( tApis ) do
+    for _,sFile in ipairs( tApis ) do
         if string.sub( sFile, 1, 1 ) ~= "." then
             local sPath = fs.combine( "rom/apis/turtle", sFile )
             if not fs.isDir( sPath ) then
@@ -896,7 +896,7 @@ end
 if pocket and fs.isDir( "rom/apis/pocket" ) then
     -- Load pocket APIs
     local tApis = fs.list( "rom/apis/pocket" )
-    for n,sFile in ipairs( tApis ) do
+    for _,sFile in ipairs( tApis ) do
         if string.sub( sFile, 1, 1 ) ~= "." then
             local sPath = fs.combine( "rom/apis/pocket", sFile )
             if not fs.isDir( sPath ) then
@@ -946,7 +946,7 @@ end
 
 -- Set default settings
 settings.set( "shell.allow_startup", true )
-settings.set( "shell.allow_disk_startup", (commands == nil) )
+settings.set( "shell.allow_disk_startup", commands == nil )
 settings.set( "shell.autocomplete", true )
 settings.set( "edit.autocomplete", true )
 settings.set( "edit.default_extension", "lua" )

src/main/resources/assets/computercraft/lua/rom/apis/command/commands.lua

@@ -33,9 +33,9 @@ local tNonNBTJSONCommands = {
     [ "title" ] = true
 }
 local tCommands = native.list()
-for n,sCommandName in ipairs(tCommands) do
+for _,sCommandName in ipairs(tCommands) do
     if env[ sCommandName ] == nil then
-        local bJSONIsNBT = (tNonNBTJSONCommands[ sCommandName ] == nil)
+        local bJSONIsNBT = tNonNBTJSONCommands[ sCommandName ] == nil
         env[ sCommandName ] = function( ... )
             local sCommand = collapseArgs( bJSONIsNBT, sCommandName, ... )
             return native.exec( sCommand )

src/main/resources/assets/computercraft/lua/rom/apis/disk.lua

@@ -62,7 +62,7 @@ end
 
 function stopAudio( name )
     if not name then
-        for n,sName in ipairs( peripheral.getNames() ) do
+        for _,sName in ipairs( peripheral.getNames() ) do
             stopAudio( sName )
         end
     else

src/main/resources/assets/computercraft/lua/rom/apis/gps.lua

@@ -13,7 +13,7 @@ local function trilaterate( A, B, C )
     local d = a2b:length()
     local ex = a2b:normalize( )
     local i = ex:dot( a2c )
-    local ey = (a2c - (ex * i)):normalize()
+    local ey = (a2c - ex * i):normalize()
     local j = ey:dot( a2c )
     local ez = ex:cross( ey )
 
@@ -24,13 +24,13 @@ local function trilaterate( A, B, C )
     local x = (r1*r1 - r2*r2 + d*d) / (2*d)
     local y = (r1*r1 - r3*r3 - x*x + (x-i)*(x-i) + j*j) / (2*j)
 
-    local result = A.vPosition + (ex * x) + (ey * y)
+    local result = A.vPosition + ex * x + ey * y
 
     local zSquared = r1*r1 - x*x - y*y
     if zSquared > 0 then
         local z = math.sqrt( zSquared )
-        local result1 = result + (ez * z)
+        local result1 = result + ez * z
-        local result2 = result - (ez * z)
+        local result2 = result - ez * z
 
         local rounded1, rounded2 = result1:round( 0.01 ), result2:round( 0.01 )
         if rounded1.x ~= rounded2.x or rounded1.y ~= rounded2.y or rounded1.z ~= rounded2.z then
@@ -66,7 +66,7 @@ function locate( _nTimeout, _bDebug )
 
     -- Find a modem
     local sModemSide = nil
-    for n,sSide in ipairs( rs.getSides() ) do
+    for _,sSide in ipairs( rs.getSides() ) do
         if peripheral.getType( sSide ) == "modem" and peripheral.call( sSide, "isWireless" ) then
             sModemSide = sSide
             break

src/main/resources/assets/computercraft/lua/rom/apis/help.lua

@@ -37,7 +37,7 @@ function topics()
     for sPath in string.gmatch(sPath, "[^:]+") do
         if fs.isDir( sPath ) then
             local tList = fs.list( sPath )
-            for n,sFile in pairs( tList ) do
+            for _,sFile in pairs( tList ) do
                 if string.sub( sFile, 1, 1 ) ~= "." then
                     if not fs.isDir( fs.combine( sPath, sFile ) ) then
                         if #sFile > 4 and sFile:sub(-4) == ".txt" then
@@ -52,7 +52,7 @@ function topics()
 
     -- Sort and return
     local tItemList = {}
-    for sItem, b in pairs( tItems ) do
+    for sItem in pairs( tItems ) do
         table.insert( tItemList, sItem )
     end
     table.sort( tItemList )

src/main/resources/assets/computercraft/lua/rom/apis/paintutils.lua

@@ -147,8 +147,8 @@ function drawBox( startX, startY, endX, endY, nColour )
         drawPixelInternal( x, maxY )
     end
 
-    if (maxY - minY) >= 2 then
+    if maxY - minY >= 2 then
-        for y=(minY+1),(maxY-1) do
+        for y=minY+1,maxY-1 do
             drawPixelInternal( minX, y )
             drawPixelInternal( maxX, y )
         end

src/main/resources/assets/computercraft/lua/rom/apis/peripheral.lua

@@ -4,12 +4,12 @@ local native = peripheral
 
 function getNames()
     local tResults = {}
-    for n,sSide in ipairs( rs.getSides() ) do
+    for _,sSide in ipairs( rs.getSides() ) do
         if native.isPresent( sSide ) then
             table.insert( tResults, sSide )
             if native.getType( sSide ) == "modem" and not native.call( sSide, "isWireless" ) then
                 local tRemote = native.call( sSide, "getNamesRemote" )
-                for n,sName in ipairs( tRemote ) do
+                for _,sName in ipairs( tRemote ) do
                     table.insert( tResults, sName )
                 end
             end
@@ -23,7 +23,7 @@ function isPresent( _sSide )
     if native.isPresent( _sSide ) then
         return true
     end
-    for n,sSide in ipairs( rs.getSides() ) do
+    for _,sSide in ipairs( rs.getSides() ) do
         if native.getType( sSide ) == "modem" and not native.call( sSide, "isWireless" ) then
             if native.call( sSide, "isPresentRemote", _sSide )  then
                 return true
@@ -38,7 +38,7 @@ function getType( _sSide )
     if native.isPresent( _sSide ) then
         return native.getType( _sSide )
     end
-    for n,sSide in ipairs( rs.getSides() ) do
+    for _,sSide in ipairs( rs.getSides() ) do
         if native.getType( sSide ) == "modem" and not native.call( sSide, "isWireless" ) then
             if native.call( sSide, "isPresentRemote", _sSide )  then
                 return native.call( sSide, "getTypeRemote", _sSide )
@@ -53,7 +53,7 @@ function getMethods( _sSide )
     if native.isPresent( _sSide ) then
         return native.getMethods( _sSide )
     end
-    for n,sSide in ipairs( rs.getSides() ) do
+    for _,sSide in ipairs( rs.getSides() ) do
         if native.getType( sSide ) == "modem" and not native.call( sSide, "isWireless" ) then
             if native.call( sSide, "isPresentRemote", _sSide )  then
                 return native.call( sSide, "getMethodsRemote", _sSide )
@@ -69,7 +69,7 @@ function call( _sSide, _sMethod, ... )
     if native.isPresent( _sSide ) then
         return native.call( _sSide, _sMethod, ... )
     end
-    for n,sSide in ipairs( rs.getSides() ) do
+    for _,sSide in ipairs( rs.getSides() ) do
         if native.getType( sSide ) == "modem" and not native.call( sSide, "isWireless" ) then
             if native.call( sSide, "isPresentRemote", _sSide )  then
                 return native.call( sSide, "callRemote", _sSide, _sMethod, ... )
@@ -84,7 +84,7 @@ function wrap( _sSide )
     if peripheral.isPresent( _sSide ) then
         local tMethods = peripheral.getMethods( _sSide )
         local tResult = {}
-        for n,sMethod in ipairs( tMethods ) do
+        for _,sMethod in ipairs( tMethods ) do
             tResult[sMethod] = function( ... )
                 return peripheral.call( _sSide, sMethod, ... )
             end
@@ -98,7 +98,7 @@ function find( sType, fnFilter )
     expect(1, sType, "string")
     expect(2, fnFilter, "function", "nil")
     local tResults = {}
-    for n,sName in ipairs( peripheral.getNames() ) do
+    for _,sName in ipairs( peripheral.getNames() ) do
         if peripheral.getType( sName ) == sType then
             local wrapped = peripheral.wrap( sName )
             if fnFilter == nil or fnFilter( sName, wrapped ) then

src/main/resources/assets/computercraft/lua/rom/apis/rednet.lua

@@ -27,7 +27,7 @@ function close( sModem )
         peripheral.call( sModem, "close", CHANNEL_BROADCAST )
     else
         -- Close all modems
-        for n,sModem in ipairs( peripheral.getNames() ) do
+        for _,sModem in ipairs( peripheral.getNames() ) do
             if isOpen( sModem ) then
                 close( sModem )
             end
@@ -44,7 +44,7 @@ function isOpen( sModem )
         end
     else
         -- Check if any modem is open
-        for n,sModem in ipairs( peripheral.getNames() ) do
+        for _,sModem in ipairs( peripheral.getNames() ) do
             if isOpen( sModem ) then
                 return true
             end
@@ -79,10 +79,10 @@ function send( nRecipient, message, sProtocol )
         sent = true
     else
         -- Send on all open modems, to the target and to repeaters
-        for n,sModem in ipairs( peripheral.getNames() ) do
+        for _,sModem in ipairs( peripheral.getNames() ) do
             if isOpen( sModem ) then
-                peripheral.call( sModem, "transmit", nRecipient, nReplyChannel, tMessage );
+                peripheral.call( sModem, "transmit", nRecipient, nReplyChannel, tMessage )
-                peripheral.call( sModem, "transmit", CHANNEL_REPEAT, nReplyChannel, tMessage );
+                peripheral.call( sModem, "transmit", CHANNEL_REPEAT, nReplyChannel, tMessage )
                 sent = true
             end
         end

src/main/resources/assets/computercraft/lua/rom/apis/settings.lua

@@ -47,7 +47,7 @@ end
 
 function getNames()
     local result = {}
-    for k,v in pairs( tSettings ) do
+    for k in pairs( tSettings ) do
         result[ #result + 1 ] = k
     end
     table.sort(result)

src/main/resources/assets/computercraft/lua/rom/apis/term.lua

@@ -1,6 +1,6 @@
 local expect = dofile("rom/modules/main/cc/expect.lua").expect
 
-local native = (term.native and term.native()) or term
+local native = term.native and term.native() or term
 local redirectTarget = native
 
 local function wrap( _sFunction )

src/main/resources/assets/computercraft/lua/rom/apis/textutils.lua

@@ -16,7 +16,7 @@ function slowWrite( sText, nRate )
         term.setCursorPos( x, y )
         sleep( nSleep )
         local nLines = write( string.sub( sText, 1, n ) )
-        local newX, newY = term.getCursorPos()
+        local _, newY = term.getCursorPos()
         y = newY - nLines
     end
 end
@@ -54,11 +54,11 @@ local function makePagedScroll( _term, _nFreeLines )
     local nativeScroll = _term.scroll
     local nFreeLines = _nFreeLines or 0
     return function( _n )
-        for n=1,_n do
+        for _=1,_n do
             nativeScroll( 1 )
 
             if nFreeLines <= 0 then
-                local w,h = _term.getSize()
+                local _,h = _term.getSize()
                 _term.setCursorPos( 1, h )
                 _term.write( "Press any key to continue" )
                 os.pullEvent( "key" )
@@ -123,7 +123,7 @@ local function tabulateCommon( bPaged, ... )
     local nCols = math.floor( w / nMaxLen )
     local nLines = 0
     local function newLine()
-        if bPaged and nLines >= (h-3) then
+        if bPaged and nLines >= h-3 then
             pagedPrint()
         else
             print()
@@ -133,14 +133,14 @@ local function tabulateCommon( bPaged, ... )
 
     local function drawCols( _t )
         local nCol = 1
-        for n, s in ipairs( _t ) do
+        for _, s in ipairs( _t ) do
             if nCol > nCols then
                 nCol = 1
                 newLine()
             end
 
             local cx, cy = term.getCursorPos()
-            cx = 1 + ((nCol - 1) * nMaxLen)
+            cx = 1 + (nCol - 1) * nMaxLen
             term.setCursorPos( cx, cy )
             term.write( s )
 
@@ -148,7 +148,7 @@ local function tabulateCommon( bPaged, ... )
         end
         print()
     end
-    for n, t in ipairs( tAll ) do
+    for _, t in ipairs( tAll ) do
         if type(t) == "table" then
             if #t > 0 then
                 drawCols( t )
@@ -280,7 +280,7 @@ local function serializeJSONImpl( t, tTracking, bNBTStyle )
                     nObjectSize = nObjectSize + 1
                 end
             end
-            for n,v in ipairs(t) do
+            for _,v in ipairs(t) do
                 local sEntry = serializeJSONImpl( v, tTracking, bNBTStyle )
                 if nArraySize == 0 then
                     sArrayResult = sArrayResult .. sEntry

src/main/resources/assets/computercraft/lua/rom/apis/vector.lua

@@ -54,9 +54,9 @@ local vector = {
 	round = function( self, nTolerance )
 	    nTolerance = nTolerance or 1.0
 		return vector.new(
-			math.floor( (self.x + (nTolerance * 0.5)) / nTolerance ) * nTolerance,
+			math.floor( (self.x + nTolerance * 0.5) / nTolerance ) * nTolerance,
-			math.floor( (self.y + (nTolerance * 0.5)) / nTolerance ) * nTolerance,
+			math.floor( (self.y + nTolerance * 0.5) / nTolerance ) * nTolerance,
-			math.floor( (self.z + (nTolerance * 0.5)) / nTolerance ) * nTolerance
+			math.floor( (self.z + nTolerance * 0.5) / nTolerance ) * nTolerance
 		)
 	end,
 	tostring = function( self )

src/main/resources/assets/computercraft/lua/rom/apis/window.lua

@@ -49,7 +49,7 @@ function create( parent, nX, nY, nWidth, nHeight, bStartVisible )
     createEmptyLines( nWidth )
 
     -- Setup
-    local bVisible = (bStartVisible ~= false)
+    local bVisible = bStartVisible ~= false
     local nCursorX = 1
     local nCursorY = 1
     local bCursorBlink = false

src/main/resources/assets/computercraft/lua/rom/programs/advanced/multishell.lua

@@ -172,7 +172,6 @@ local function resizeWindows()
     end
     for n=1,#tProcesses do
         local tProcess = tProcesses[n]
-        local window = tProcess.window
         local x,y = tProcess.window.getCursorPos()
         if y > windowHeight then
             tProcess.window.scroll( y - windowHeight )
@@ -232,7 +231,7 @@ function multishell.launch( tProgramEnv, sProgramPath, ... )
     expect(1, tProgramEnv, "table")
     expect(2, sProgramPath, "string")
     local previousTerm = term.current()
-    setMenuVisible( (#tProcesses + 1) >= 2 )
+    setMenuVisible( #tProcesses + 1 >= 2 )
     local nResult = launchProcess( false, tProgramEnv, sProgramPath, ... )
     redrawMenu()
     term.redirect( previousTerm )
@@ -299,7 +298,7 @@ while #tProcesses > 0 do
             end
         else
             -- Passthrough to current process
-            resumeProcess( nCurrentProcess, sEvent, button, x, (bShowMenu and y-1) or y )
+            resumeProcess( nCurrentProcess, sEvent, button, x, bShowMenu and y-1 or y )
             if cullProcess( nCurrentProcess ) then
                 setMenuVisible( #tProcesses >= 2 )
                 redrawMenu()
@@ -319,7 +318,7 @@ while #tProcesses > 0 do
             end
         elseif not (bShowMenu and y == 1) then
             -- Passthrough to current process
-            resumeProcess( nCurrentProcess, sEvent, p1, x, (bShowMenu and y-1) or y )
+            resumeProcess( nCurrentProcess, sEvent, p1, x, bShowMenu and y-1 or y )
             if cullProcess( nCurrentProcess ) then
                 setMenuVisible( #tProcesses >= 2 )
                 redrawMenu()

src/main/resources/assets/computercraft/lua/rom/programs/copy.lua

@@ -9,7 +9,7 @@ local sSource = shell.resolve( tArgs[1] )
 local sDest = shell.resolve( tArgs[2] )
 local tFiles = fs.find( sSource )
 if #tFiles > 0 then
-    for n,sFile in ipairs( tFiles ) do
+    for _,sFile in ipairs( tFiles ) do
         if fs.isDir( sDest ) then
             fs.copy( sFile, fs.combine( sDest, fs.getName(sFile) ) )
         elseif #tFiles == 1 then

src/main/resources/assets/computercraft/lua/rom/programs/delete.lua

@@ -8,7 +8,7 @@ end
 for i = 1, args.n do
     local files = fs.find(shell.resolve(args[i]))
     if #files > 0 then
-        for n, file in ipairs(files) do
+        for _, file in ipairs(files) do
             local ok, err = pcall(fs.delete, file)
             if not ok then
                 printError((err:gsub("^pcall: ", "")))

src/main/resources/assets/computercraft/lua/rom/programs/drive.lua

@@ -10,9 +10,9 @@ if fs.exists( sPath ) then
     write( fs.getDrive( sPath ) .. " (" )
     local nSpace = fs.getFreeSpace( sPath )
     if nSpace >= 1000 * 1000 then
-        print( (math.floor( nSpace / (100 * 1000) ) / 10) .. "MB remaining)" )
+        print( math.floor( nSpace / (100 * 1000) ) / 10 .. "MB remaining)" )
     elseif nSpace >= 1000 then
-        print( (math.floor( nSpace / 100 ) / 10) .. "KB remaining)" )
+        print( math.floor( nSpace / 100 ) / 10 .. "KB remaining)" )
     else
         print( nSpace .. "B remaining)" )
     end

src/main/resources/assets/computercraft/lua/rom/programs/edit.lua

@@ -95,7 +95,7 @@ local function save( _sPath )
     local function innerSave()
         file, fileerr = fs.open( _sPath, "w" )
         if file then
-            for n, sLine in ipairs( tLines ) do
+            for _, sLine in ipairs( tLines ) do
                 file.write( sLine .. "\n" )
             end
         else
@@ -287,7 +287,7 @@ local tMenuFuncs = {
         if bReadOnly then
             sStatus = "Access denied"
         else
-            local ok, err, fileerr  = save( sPath )
+            local ok, _, fileerr  = save( sPath )
             if ok then
                 sStatus="Saved to "..sPath
             else
@@ -357,7 +357,7 @@ local tMenuFuncs = {
         term.redirect( printerTerminal )
         local ok, error = pcall( function()
             term.scroll()
-            for n, sLine in ipairs( tLines ) do
+            for _, sLine in ipairs( tLines ) do
                 print( sLine )
             end
         end )
@@ -385,7 +385,7 @@ local tMenuFuncs = {
     end,
     Run = function()
         local sTempPath = "/.temp"
-        local ok, err = save( sTempPath )
+        local ok = save( sTempPath )
         if ok then
             local nTask = shell.openTab( sTempPath )
             if nTask then
@@ -411,7 +411,7 @@ local function doMenuItem( _n )
 end
 
 local function setCursor( newX, newY )
-    local oldX, oldY = x, y
+    local _, oldY = x, y
     x, y = newX, newY
     local screenX = x - scrollX
     local screenY = y - scrollY
@@ -476,7 +476,6 @@ end
 while bRunning do
     local sEvent, param, param2, param3 = os.pullEvent()
     if sEvent == "key" then
-        local oldX, oldY = x, y
         if param == keys.up then
             -- Up
             if not bMenu then

src/main/resources/assets/computercraft/lua/rom/programs/fun/advanced/paint.lua

@@ -186,8 +186,8 @@ local function drawInterface()
     term.write("\127\127")
 
     -- Left and Right Selected Colours
-    for i=18,18 do
+    do
-        term.setCursorPos(w-1, i)
+        term.setCursorPos(w-1, 18)
         if leftColour ~= nil then
             term.setBackgroundColour( leftColour )
             term.write(" ")
@@ -269,7 +269,7 @@ local function accessMenu()
         for k,v in pairs(mChoices) do
             if selection==k then
                 term.setTextColour(colours.yellow)
-                local ox,_ = term.getCursorPos()
+                local ox = term.getCursorPos()
                 term.write("["..string.rep(" ",#v).."]")
                 term.setCursorPos(ox+1,h)
                 term.setTextColour(colours.white)

src/main/resources/assets/computercraft/lua/rom/programs/fun/advanced/redirection.lua

@@ -66,8 +66,8 @@ local function printCentred( yc, stg )
 end
 
 local function centerOrgin()
-    XOrgin = math.floor((TermW/2)-(SizeW/2))
+    XOrgin = math.floor(TermW/2-SizeW/2)
-    YOrgin = math.floor((TermH/2)-(SizeH/2))
+    YOrgin = math.floor(TermH/2-SizeH/2)
 end
 
 local function reMap()
@@ -177,7 +177,6 @@ local function loadLevel(nNum)
     local sLevelD = sDir .. "/levels/" .. tostring(nNum)..".dat"
     if not ( fs.exists(sLevelD) or fs.isDir(sLevelD) ) then return error("Level Not Exists : "..sLevelD) end
     fLevel = fs.open(sLevelD,"r")
-    local Line = 0
     local wl = true
     Blocks = tonumber(string.sub(fLevel.readLine(),1,1))
     local xSize = string.len(fLevel.readLine())+2
@@ -557,7 +556,7 @@ function InterFace.render()
         elseif p3 == TermH and p2 >= TermW-4 and p2 <= TermW-3 then
             bPaused = not bPaused
             fSpeedS = false
-            Speed = (bPaused and 0) or nSpeed
+            Speed = bPaused and 0 or nSpeed
             if Speed > 0 then
                 Tick = os.startTimer(Speed)
             else
@@ -567,7 +566,7 @@ function InterFace.render()
         elseif p3 == TermH and p2 >= TermW-1 then
             bPaused = false
             fSpeedS = not fSpeedS
-            Speed = (fSpeedS and fSpeed) or nSpeed
+            Speed = fSpeedS and fSpeed or nSpeed
             Tick = os.startTimer(Speed)
             InterFace.drawBar()
         elseif p3-1 < YOrgin+SizeH+1 and p3-1 > YOrgin and
@@ -596,7 +595,6 @@ local function startG(LevelN)
     drawStars()
     loadLevel(LevelN)
     centerOrgin()
-    local create = true
     drawMap()
     InterFace.drawBar()
     gRender("start")

src/main/resources/assets/computercraft/lua/rom/programs/fun/adventure.lua

@@ -342,7 +342,7 @@ local function getTimeOfDay()
 end
 
 local function isSunny()
-    return (getTimeOfDay() < 10)
+    return getTimeOfDay() < 10
 end
 
 local function getRoom( x, y, z, dontCreate )
@@ -365,7 +365,7 @@ local function getRoom( x, y, z, dontCreate )
 
             -- Add animals
             if math.random(1,3) == 1 then
-                for n = 1,math.random(1,2) do
+                for _ = 1,math.random(1,2) do
                     local sAnimal = tAnimals[ math.random( 1, #tAnimals ) ]
                     room.items[ sAnimal ] = items[ sAnimal ]
                 end
@@ -478,7 +478,7 @@ local function findItem( _tList, _sQuery )
             return sItem
         end
         if tItem.aliases ~= nil then
-            for n, sAlias in pairs( tItem.aliases ) do
+            for _, sAlias in pairs( tItem.aliases ) do
                 if sAlias == _sQuery then
                     return sItem
                 end
@@ -613,7 +613,7 @@ local function doCommand( text )
     end
 
     for sCommand, t in pairs( tMatches ) do
-        for n, sMatch in pairs( t ) do
+        for _, sMatch in pairs( t ) do
             local tCaptures = { string.match( text, "^" .. sMatch .. "$" ) }
             if #tCaptures ~= 0 then
                 local fnCommand = commands[ sCommand ]
@@ -679,7 +679,7 @@ function commands.look( _sTarget )
             end
 
             if tItem then
-                print( tItem.desc or ("You see nothing special about "..sItem..".") )
+                print( tItem.desc or "You see nothing special about "..sItem.."." )
             else
                 print( "You don't see any ".._sTarget.." here." )
             end
@@ -752,7 +752,7 @@ function commands.dig( _sDir, _sTool )
         tTool = inventory[ sTool ]
     end
 
-    local bActuallyDigging = (room.exits[ _sDir ] ~= true)
+    local bActuallyDigging = room.exits[ _sDir ] ~= true
     if bActuallyDigging then
         if sTool == nil or tTool.toolType ~= "pick" then
             print( "You need to use a pickaxe to dig through stone." )
@@ -1021,7 +1021,7 @@ function commands.cbreak( _sItem, _sTool )
                 print( "The "..tItem.aliases[1].." dies." )
 
                 if tItem.drops then
-                    for n, sDrop in pairs( tItem.drops ) do
+                    for _, sDrop in pairs( tItem.drops ) do
                         if not room.items[sDrop] then
                             print( "The "..tItem.aliases[1].." dropped "..sDrop.."." )
                             room.items[sDrop] = items[sDrop]
@@ -1037,7 +1037,7 @@ function commands.cbreak( _sItem, _sTool )
             end
 
             if tItem.hitDrops then
-                for n, sDrop in pairs( tItem.hitDrops ) do
+                for _, sDrop in pairs( tItem.hitDrops ) do
                     if not room.items[sDrop] then
                         print( "The "..tItem.aliases[1].." dropped "..sDrop.."." )
                         room.items[sDrop] = items[sDrop]
@@ -1071,18 +1071,17 @@ function commands.craft( _sItem )
         return
     end
 
-    local room = getRoom( x,y,z )
     local sItem = findItem( items, _sItem )
-    local tRecipe = (sItem and tRecipes[ sItem ]) or nil
+    local tRecipe = sItem and tRecipes[ sItem ] or nil
     if tRecipe then
-        for n,sReq in ipairs( tRecipe ) do
+        for _,sReq in ipairs( tRecipe ) do
             if inventory[sReq] == nil then
                 print( "You don't have the items you need to craft "..sItem.."." )
                 return
             end
         end
 
-        for n,sReq in ipairs( tRecipe ) do
+        for _,sReq in ipairs( tRecipe ) do
             inventory[sReq] = nil
         end
         inventory[ sItem ] = items[ sItem ]
@@ -1223,7 +1222,7 @@ local function simulate()
 
                     -- Spawn monsters
                     if room.nMonsters < 2 and
-                       ((h == 0 and not isSunny() and not room.items["a torch"]) or room.dark) and
+                       (h == 0 and not isSunny() and not room.items["a torch"] or room.dark) and
                        math.random(1,6) == 1 then
 
                         local sMonster = tMonsters[ math.random(1,#tMonsters) ]
@@ -1240,7 +1239,7 @@ local function simulate()
 
                     -- Burn monsters
                     if h == 0 and isSunny() then
-                        for n,sMonster in ipairs( tMonsters ) do
+                        for _,sMonster in ipairs( tMonsters ) do
                             if room.items[sMonster] and items[sMonster].nocturnal then
                                 room.items[sMonster] = nil
                                    if sx == 0 and sy == 0 and sz == 0 and not room.dark then
@@ -1258,10 +1257,10 @@ local function simulate()
     -- Make monsters attack
     local room = getRoom( x, y, z )
     if nTimeInRoom >= 2 and not bNewMonstersThisRoom then
-        for n,sMonster in ipairs( tMonsters ) do
+        for _,sMonster in ipairs( tMonsters ) do
             if room.items[sMonster] then
                 if math.random(1,4) == 1 and
-                   not (y == 0 and isSunny() and (sMonster == "a spider")) then
+                   not (y == 0 and isSunny() and sMonster == "a spider") then
                     if sMonster == "a creeper" then
                         if room.dark then
                             print( "A creeper explodes." )

src/main/resources/assets/computercraft/lua/rom/programs/fun/dj.lua

@@ -23,7 +23,7 @@ elseif sCommand == "play" or sCommand == nil then
     if sName == nil then
         -- No disc specified, pick one at random
         local tNames = {}
-        for n,sName in ipairs( peripheral.getNames() ) do
+        for _,sName in ipairs( peripheral.getNames() ) do
             if disk.isPresent( sName ) and disk.hasAudio( sName ) then
                 table.insert( tNames, sName )
             end

src/main/resources/assets/computercraft/lua/rom/programs/fun/worm.lua

@@ -2,15 +2,13 @@
 -- Display the start screen
 local w,h = term.getSize()
 
-local titleColour, headingColour, textColour, wormColour, fruitColour
+local headingColour, textColour, wormColour, fruitColour
 if term.isColour() then
-    titleColour = colours.red
     headingColour = colours.yellow
     textColour = colours.white
     wormColour = colours.green
     fruitColour = colours.red
 else
-    titleColour = colours.white
     headingColour = colours.white
     textColour = colours.white
     wormColour = colours.white
@@ -27,8 +25,6 @@ end
 local xVel,yVel = 1,0
 local xPos, yPos = math.floor(w/2), math.floor(h/2)
 local pxVel, pyVel = nil, nil
-
-local nLength = 1
 local nExtraLength = 6
 local bRunning = true
 
@@ -103,7 +99,6 @@ local function drawMenu()
 end
 
 local function update( )
-    local x,y = xPos,yPos
     if pxVel and pyVel then
         xVel, yVel = pxVel, pyVel
         pxVel, pyVel = nil, nil
@@ -190,7 +185,7 @@ end
 drawMenu()
 drawFrontend()
 while true do
-    local e,key = os.pullEvent( "key" )
+    local _,key = os.pullEvent( "key" )
     if key == keys.up or key == keys.w then
         -- Up
         if nDifficulty > 1 then
@@ -228,7 +223,7 @@ addFruit()
 -- Play the game
 local timer = os.startTimer(0)
 while bRunning do
-    local event, p1, p2 = os.pullEvent()
+    local event, p1 = os.pullEvent()
     if event == "timer" and p1 == timer then
         timer = os.startTimer(nInterval)
         update( false )

src/main/resources/assets/computercraft/lua/rom/programs/gps.lua

@@ -28,7 +28,7 @@ elseif sCommand == "host" then
 
     -- Find a modem
     local sModemSide = nil
-    for n,sSide in ipairs( rs.getSides() ) do
+    for _,sSide in ipairs( rs.getSides() ) do
         if peripheral.getType( sSide ) == "modem" and peripheral.call( sSide, "isWireless" ) then
             sModemSide = sSide
             break
@@ -80,7 +80,7 @@ elseif sCommand == "host" then
                 -- Print the number of requests handled
                 nServed = nServed + 1
                 if nServed > 1 then
-                    local x,y = term.getCursorPos()
+                    local _,y = term.getCursorPos()
                     term.setCursorPos(1,y-1)
                 end
                 print( nServed.." GPS requests served" )

src/main/resources/assets/computercraft/lua/rom/programs/help.lua

@@ -14,7 +14,7 @@ if sTopic == "index" then
 end
 
 local sFile = help.lookup( sTopic )
-local file = ((sFile ~= nil) and io.open( sFile )) or nil
+local file = sFile ~= nil and io.open( sFile ) or nil
 if file then
     local sContents = file:read("*a")
     file:close()

src/main/resources/assets/computercraft/lua/rom/programs/list.lua

@@ -18,7 +18,7 @@ local tFiles = {}
 local tDirs = {}
 
 local bShowHidden = settings.get( "list.show_hidden" )
-for n, sItem in pairs( tAll ) do
+for _, sItem in pairs( tAll ) do
     if bShowHidden or string.sub( sItem, 1, 1 ) ~= "." then
         local sPath = fs.combine( sDir, sItem )
         if fs.isDir( sPath ) then

src/main/resources/assets/computercraft/lua/rom/programs/lua.lua

@@ -67,7 +67,7 @@ while bRunning do
 
     local nForcePrint = 0
     local func, e = load( s, "=lua", "t", tEnv )
-    local func2, e2 = load( "return _echo("..s..");", "=lua", "t", tEnv )
+    local func2 = load( "return _echo("..s..");", "=lua", "t", tEnv )
     if not func then
         if func2 then
             func = func2
@@ -84,7 +84,7 @@ while bRunning do
         local tResults = table.pack( pcall( func ) )
         if tResults[1] then
             local n = 1
-            while n < tResults.n or (n <= nForcePrint) do
+            while n < tResults.n or n <= nForcePrint do
                 local value = tResults[ n + 1 ]
                 if type( value ) == "table" then
                     local metatable = getmetatable( value )

src/main/resources/assets/computercraft/lua/rom/programs/move.lua

@@ -9,7 +9,7 @@ local sSource = shell.resolve( tArgs[1] )
 local sDest = shell.resolve( tArgs[2] )
 local tFiles = fs.find( sSource )
 if #tFiles > 0 then
-    for n,sFile in ipairs( tFiles ) do
+    for _,sFile in ipairs( tFiles ) do
         if fs.isDir( sDest ) then
             fs.move( sFile, fs.combine( sDest, fs.getName(sFile) ) )
         elseif #tFiles == 1 then

src/main/resources/assets/computercraft/lua/rom/programs/pocket/falling.lua

@@ -424,7 +424,7 @@ local function playGame()
     end
 
     if #rows>0 then
-      for i=1,4 do
+      for _=1,4 do
         sleep(.1)
         for r=1,#rows do
           r=rows[r]
@@ -469,7 +469,6 @@ local function playGame()
   end
 
   local function blockFall()
-    local result = false
     if testBlockAt(curBlock,curX,curY+1,curRot) then
       pitBlock(curBlock,curX,curY,curRot)
       --detect rows that clear
@@ -524,16 +523,16 @@ local function playGame()
         dropTimer=os.startTimer(dropSpeed)
       end
       if dx+dr~=0 then
-        if not testBlockAt(curBlock,curX+dx,curY+dy,(dr>0 and curRot%#curBlock+dr or curRot)) then
+        if not testBlockAt(curBlock,curX+dx,curY+dy,dr>0 and curRot%#curBlock+dr or curRot) then
           eraseBlockAt(curBlock,curX,curY,curRot)
           curX=curX+dx
           curY=curY+dy
-          curRot=dr==0 and curRot or (curRot%#curBlock+dr)
+          curRot=dr==0 and curRot or curRot%#curBlock+dr
           drawBlockAt(curBlock,curX,curY,curRot)
         end
       end
     elseif e[1]=="term_resize" then
-      local w,h=term.getSize()
+      local _,h=term.getSize()
       if h==20 then
         heightAdjust=0
       else
@@ -617,7 +616,7 @@ local function runMenu()
         level=math.max(level-1,1)
         drawMenu()
       elseif key>=keys.one and key<=keys.nine and selected==1 then
-        level=(key-keys.one) + 1
+        level=key-keys.one + 1
         drawMenu()
       elseif key==keys.up or key==keys.w then
         selected=selected-1

src/main/resources/assets/computercraft/lua/rom/programs/rednet/chat.lua

@@ -9,7 +9,7 @@ end
 
 local sOpenedModem = nil
 local function openModem()
-    for n,sModem in ipairs( peripheral.getNames() ) do
+    for _,sModem in ipairs( peripheral.getNames() ) do
         if peripheral.getType( sModem ) == "modem" then
             if not rednet.isOpen( sModem ) then
                 rednet.open( sModem )
@@ -94,7 +94,7 @@ if sCommand == "host" then
     end
 
     local function printUsers()
-        local x,y = term.getCursorPos()
+        local _,y = term.getCursorPos()
         term.setCursorPos( 1, y - 1 )
         term.clearLine()
         if nUsers == 1 then
@@ -108,7 +108,7 @@ if sCommand == "host" then
     local ok, error = pcall( function()
         parallel.waitForAny( function()
             while true do
-                local sEvent, timer = os.pullEvent( "timer" )
+                local _, timer = os.pullEvent( "timer" )
                 local nUserID = tPingPongTimer[ timer ]
                 if nUserID and tUsers[ nUserID ] then
                     local tUser = tUsers[ nUserID ]
@@ -148,7 +148,7 @@ if sCommand == "host" then
                     ["users"] = function( tUser, sContent )
                         send( "* Connected Users:", tUser.nUserID )
                         local sUsers = "*"
-                        for nUserID, tUser in pairs( tUsers ) do
+                        for _, tUser in pairs( tUsers ) do
                             sUsers = sUsers .. " " .. tUser.sUsername
                         end
                         send( sUsers, tUser.nUserID )
@@ -156,7 +156,7 @@ if sCommand == "host" then
                     ["help"] = function( tUser, sContent )
                         send( "* Available commands:", tUser.nUserID )
                         local sCommands = "*"
-                        for sCommand, fnCommand in pairs( tCommands ) do
+                        for sCommand in pairs( tCommands ) do
                             sCommands = sCommands .. " /" .. sCommand
                         end
                         send( sCommands.." /logout", tUser.nUserID )
@@ -297,8 +297,7 @@ elseif sCommand == "join" then
     promptWindow.restoreCursor()
 
     local function drawTitle()
-        local x,y = titleWindow.getCursorPos()
+        local w = titleWindow.getSize()
-        local w,h = titleWindow.getSize()
         local sTitle = sUsername.." on "..sHostname
         titleWindow.setTextColour( highlightColour )
         titleWindow.setCursorPos( math.floor( w/2 - string.len(sTitle)/2 ), 1 )
@@ -410,7 +409,7 @@ elseif sCommand == "join" then
     term.redirect( parentTerm )
 
     -- Print error notice
-    local w,h = term.getSize()
+    local _,h = term.getSize()
     term.setCursorPos( 1, h )
     term.clearLine()
     term.setCursorBlink( false )

src/main/resources/assets/computercraft/lua/rom/programs/rednet/repeat.lua

@@ -1,7 +1,7 @@
 
 -- Find modems
 local tModems = {}
-for n,sModem in ipairs( peripheral.getNames() ) do
+for _,sModem in ipairs( peripheral.getNames() ) do
     if peripheral.getType( sModem ) == "modem" then
         table.insert( tModems, sModem )
     end
@@ -59,7 +59,7 @@ local ok, error = pcall( function()
 
                         -- Log the event
                         nTransmittedMessages = nTransmittedMessages + 1
-                        local x,y = term.getCursorPos()
+                        local _,y = term.getCursorPos()
                         term.setCursorPos( 1, y - 1 )
                         term.clearLine()
                         if nTransmittedMessages == 1 then

src/main/resources/assets/computercraft/lua/rom/programs/redstone.lua

@@ -17,7 +17,7 @@ if sCommand == "probe" then
 
     local count = 0
     local bundledCount = 0
-    for n,sSide in ipairs( redstone.getSides() ) do
+    for _,sSide in ipairs( redstone.getSides() ) do
         if redstone.getBundledInput( sSide ) > 0 then
             bundledCount = bundledCount + 1
         end
@@ -39,7 +39,7 @@ if sCommand == "probe" then
     if bundledCount > 0 then
         print()
         print( "Bundled inputs:" )
-        for i,sSide in ipairs( redstone.getSides() ) do
+        for _,sSide in ipairs( redstone.getSides() ) do
             local nInput = redstone.getBundledInput( sSide )
             if nInput ~= 0 then
                 write( sSide..": " )
@@ -69,7 +69,7 @@ elseif sCommand == "pulse" then
     local sSide = tArgs[2]
     local nCount = tonumber( tArgs[3] ) or 1
     local nPeriod = tonumber( tArgs[4] ) or 0.5
-    for n=1,nCount do
+    for _=1,nCount do
         redstone.setOutput( sSide, true )
         sleep( nPeriod / 2 )
         redstone.setOutput( sSide, false )

src/main/resources/assets/computercraft/lua/rom/programs/set.lua

@@ -2,7 +2,7 @@
 local tArgs = { ... }
 if #tArgs == 0 then
     -- "set"
-    local x,y = term.getCursorPos()
+    local _,y = term.getCursorPos()
     local tSettings = {}
     for n,sName in ipairs( settings.getNames() ) do
         tSettings[n] = textutils.serialize(sName) .. " is " .. textutils.serialize(settings.get(sName))

src/main/resources/assets/computercraft/lua/rom/programs/shell.lua

@@ -9,10 +9,10 @@ if multishell then
 end
 
 local bExit = false
-local sDir = (parentShell and parentShell.dir()) or ""
+local sDir = parentShell and parentShell.dir() or ""
-local sPath = (parentShell and parentShell.path()) or ".:/rom/programs"
+local sPath = parentShell and parentShell.path() or ".:/rom/programs"
-local tAliases = (parentShell and parentShell.aliases()) or {}
+local tAliases = parentShell and parentShell.aliases() or {}
-local tCompletionInfo = (parentShell and parentShell.getCompletionInfo()) or {}
+local tCompletionInfo = parentShell and parentShell.getCompletionInfo() or {}
 local tProgramStack = {}
 
 local shell = {}
@@ -287,7 +287,7 @@ function shell.programs( _bIncludeHidden )
 
     -- Sort and return
     local tItemList = {}
-    for sItem, b in pairs( tItems ) do
+    for sItem in pairs( tItems ) do
         table.insert( tItemList, sItem )
     end
     table.sort( tItemList )
@@ -304,7 +304,7 @@ local function completeProgram( sLine )
         local tSeen = {}
 
         -- Add aliases
-        for sAlias, sCommand in pairs( tAliases ) do
+        for sAlias in pairs( tAliases ) do
             if #sAlias > #sLine and string.sub( sAlias, 1, #sLine ) == sLine then
                 local sResult = string.sub( sAlias, #sLine + 1 )
                 if not tSeen[ sResult ] then

src/main/resources/assets/computercraft/lua/rom/programs/turtle/dance.lua

@@ -81,7 +81,7 @@ textutils.slowWrite( "Preparing to get down." )
 textutils.slowPrint( "..", 0.75 )
 
 local sAudio = nil
-for n,sName in pairs( peripheral.getNames() ) do
+for _,sName in pairs( peripheral.getNames() ) do
     if disk.hasAudio( sName ) then
         disk.playAudio( sName )
         print( "Jamming to "..disk.getAudioTitle( sName ) )
@@ -95,7 +95,7 @@ print( "Press any key to stop the groove" )
 parallel.waitForAny(
     function()
         while not bEnd do
-            local event, key = os.pullEvent("key")
+            local _, key = os.pullEvent("key")
             if key ~= keys.escape then
                 return
             end

src/main/resources/assets/computercraft/lua/rom/programs/turtle/excavate.lua

@@ -81,7 +81,7 @@ local function collect()
     if nTotalItems > collected then
         collected = nTotalItems
         if math.fmod(collected + unloaded, 50) == 0 then
-            print( "Mined "..(collected + unloaded).." items." )
+            print( "Mined "..collected + unloaded.." items." )
         end
     end
 
@@ -98,9 +98,8 @@ function refuel( ammount )
         return true
     end
 
-    local needed = ammount or (xPos + zPos + depth + 2)
+    local needed = ammount or xPos + zPos + depth + 2
     if turtle.getFuelLevel() < needed then
-        local fueled = false
         for n=1,16 do
             if turtle.getItemCount(n) > 0 then
                 turtle.select(n)
@@ -292,7 +291,7 @@ local alternate = 0
 local done = false
 while not done do
     for n=1,size do
-        for m=1,size-1 do
+        for _=1,size-1 do
             if not tryForwards() then
                 done = true
                 break
@@ -354,4 +353,4 @@ if reseal then
     turtle.placeDown()
 end
 
-print( "Mined "..(collected + unloaded).." items total." )
+print( "Mined "..collected + unloaded.." items total." )

src/main/resources/assets/computercraft/lua/rom/programs/turtle/refuel.lua

@@ -23,7 +23,7 @@ end
 if turtle.getFuelLevel() ~= "unlimited" then
     for n = 1, 16 do
         -- Stop if we've reached the limit, or are fully refuelled.
-        if (nLimit and nLimit <= 0) or turtle.getFuelLevel() >= turtle.getFuelLimit() then
+        if nLimit and nLimit <= 0 or turtle.getFuelLevel() >= turtle.getFuelLimit() then
             break
         end
 

src/main/resources/assets/computercraft/lua/rom/programs/turtle/tunnel.lua

@@ -15,8 +15,6 @@ if length < 1 then
     print( "Tunnel length must be positive" )
     return
 end
-
-local depth = 0
 local collected = 0
 
 local function collect()

src/main/resources/assets/computercraft/lua/rom/programs/turtle/turn.lua

@@ -31,7 +31,7 @@ while nArg <= #tArgs do
 
     local fnHandler = tHandlers[string.lower(sDirection)]
     if fnHandler then
-        for n=1,nDistance do
+        for _=1,nDistance do
             fnHandler( nArg )
         end
     else

src/main/resources/assets/computercraft/lua/rom/startup.lua

@@ -163,7 +163,7 @@ if settings.get( "shell.allow_startup" ) then
     tUserStartups = findStartups( "/" )
 end
 if settings.get( "shell.allow_disk_startup" ) then
-    for n,sName in pairs( peripheral.getNames() ) do
+    for _,sName in pairs( peripheral.getNames() ) do
         if disk.isPresent( sName ) and disk.hasData( sName ) then
             local startups = findStartups( disk.getMountPath( sName ) )
             if startups then