module ShellCheck.Analytics (runAnalytics, ShellCheck.Analytics.runTests) where
import ShellCheck.AST
import ShellCheck.ASTLib
import ShellCheck.AnalyzerLib
import ShellCheck.Data
import ShellCheck.Parser
import ShellCheck.Interface
import ShellCheck.Regex
import Control.Arrow (first)
import Control.Monad
import Control.Monad.Identity
import Control.Monad.State
import Control.Monad.Writer
import Control.Monad.Reader
import Data.Char
import Data.Functor
import Data.Function (on)
import Data.List
import Data.Maybe
import Data.Ord
import Debug.Trace
import qualified Data.Map as Map
import Test.QuickCheck.All (forAllProperties)
import Test.QuickCheck.Test (quickCheckWithResult, stdArgs, maxSuccess)
treeChecks :: [Parameters -> Token -> [TokenComment]]
treeChecks = [
runNodeAnalysis
(\p t -> (mapM_ ((\ f -> f t) . (\ f -> f p))
(nodeChecks ++ checksFor (shellType p))))
,subshellAssignmentCheck
,checkSpacefulness
,checkQuotesInLiterals
,checkShebangParameters
,checkFunctionsUsedExternally
,checkUnusedAssignments
,checkUnpassedInFunctions
,checkArrayWithoutIndex
,checkShebang
,checkUnassignedReferences
,checkUncheckedCd
]
checksFor Sh = [
checkBashisms
,checkTimeParameters
,checkForDecimals
,checkTimedCommand
]
checksFor Dash = [
checkBashisms
,checkForDecimals
,checkLocalScope
,checkTimedCommand
]
checksFor Ksh = [
checkEchoSed
]
checksFor Bash = [
checkTimeParameters
,checkBraceExpansionVars
,checkEchoSed
,checkForDecimals
,checkLocalScope
,checkMultiDimensionalArrays
]
runAnalytics :: AnalysisSpec -> [TokenComment]
runAnalytics options =
runList options treeChecks
runList :: AnalysisSpec -> [Parameters -> Token -> [TokenComment]]
-> [TokenComment]
runList spec list = notes
where
root = asScript spec
params = makeParameters spec
notes = concatMap (\f -> f params root) list
checkList l t = concatMap (\f -> f t) l
runNodeAnalysis f p t = execWriter (doAnalysis (f p) t)
nodeChecks :: [Parameters -> Token -> Writer [TokenComment] ()]
nodeChecks = [
checkUuoc
,checkPipePitfalls
,checkForInQuoted
,checkForInLs
,checkShorthandIf
,checkDollarStar
,checkUnquotedDollarAt
,checkStderrRedirect
,checkUnquotedN
,checkNumberComparisons
,checkSingleBracketOperators
,checkDoubleBracketOperators
,checkLiteralBreakingTest
,checkConstantNoary
,checkDivBeforeMult
,checkArithmeticDeref
,checkArithmeticBadOctal
,checkComparisonAgainstGlob
,checkCommarrays
,checkOrNeq
,checkEchoWc
,checkConstantIfs
,checkPipedAssignment
,checkAssignAteCommand
,checkUuoeVar
,checkQuotedCondRegex
,checkForInCat
,checkFindExec
,checkValidCondOps
,checkGlobbedRegex
,checkTestRedirects
,checkIndirectExpansion
,checkSudoRedirect
,checkPS1Assignments
,checkBackticks
,checkInexplicablyUnquoted
,checkTildeInQuotes
,checkLonelyDotDash
,checkSpuriousExec
,checkSpuriousExpansion
,checkDollarBrackets
,checkSshHereDoc
,checkGlobsAsOptions
,checkWhileReadPitfalls
,checkArithmeticOpCommand
,checkCharRangeGlob
,checkUnquotedExpansions
,checkSingleQuotedVariables
,checkRedirectToSame
,checkPrefixAssignmentReference
,checkLoopKeywordScope
,checkCdAndBack
,checkWrongArithmeticAssignment
,checkConditionalAndOrs
,checkFunctionDeclarations
,checkCatastrophicRm
,checkStderrPipe
,checkOverridingPath
,checkArrayAsString
,checkUnsupported
,checkMultipleAppends
,checkSuspiciousIFS
,checkShouldUseGrepQ
,checkTestGlobs
,checkConcatenatedDollarAt
,checkTildeInPath
,checkMaskedReturns
,checkReadWithoutR
,checkLoopVariableReassignment
,checkTrailingBracket
,checkReturnAgainstZero
]
wouldHaveBeenGlob s = '*' `elem` s
verify :: (Parameters -> Token -> Writer [TokenComment] ()) -> String -> Bool
verify f s = checkNode f s == Just True
verifyNot :: (Parameters -> Token -> Writer [TokenComment] ()) -> String -> Bool
verifyNot f s = checkNode f s == Just False
verifyTree :: (Parameters -> Token -> [TokenComment]) -> String -> Bool
verifyTree f s = producesComments f s == Just True
verifyNotTree :: (Parameters -> Token -> [TokenComment]) -> String -> Bool
verifyNotTree f s = producesComments f s == Just False
checkCommand str f t@(T_SimpleCommand id _ (cmd:rest)) =
when (t `isCommand` str) $ f cmd rest
checkCommand _ _ _ = return ()
checkUnqualifiedCommand str f t@(T_SimpleCommand id _ (cmd:rest)) =
when (t `isUnqualifiedCommand` str) $ f cmd rest
checkUnqualifiedCommand _ _ _ = return ()
checkNode f = producesComments (runNodeAnalysis f)
producesComments :: (Parameters -> Token -> [TokenComment]) -> String -> Maybe Bool
producesComments f s = do
root <- pScript s
return . not . null $ runList (defaultSpec root) [f]
dist :: Eq a => [a] -> [a] -> Int
dist a b
= last (if lab == 0 then mainDiag
else if lab > 0 then lowers !! (lab 1)
else uppers !! (1 lab))
where mainDiag = oneDiag a b (head uppers) (1 : head lowers)
uppers = eachDiag a b (mainDiag : uppers)
lowers = eachDiag b a (mainDiag : lowers)
eachDiag a [] diags = []
eachDiag a (bch:bs) (lastDiag:diags) = oneDiag a bs nextDiag lastDiag : eachDiag a bs diags
where nextDiag = head (tail diags)
oneDiag a b diagAbove diagBelow = thisdiag
where doDiag [] b nw n w = []
doDiag a [] nw n w = []
doDiag (ach:as) (bch:bs) nw n w = me : doDiag as bs me (tail n) (tail w)
where me = if ach == bch then nw else 1 + min3 (head w) nw (head n)
firstelt = 1 + head diagBelow
thisdiag = firstelt : doDiag a b firstelt diagAbove (tail diagBelow)
lab = length a length b
min3 x y z = if x < y then x else min y z
hasFloatingPoint params = shellType params == Ksh
isCondition [] = False
isCondition [_] = False
isCondition (child:parent:rest) =
getId child `elem` map getId (getConditionChildren parent) || isCondition (parent:rest)
where
getConditionChildren t =
case t of
T_AndIf _ left right -> [left]
T_OrIf id left right -> [left]
T_IfExpression id conditions elses -> concatMap (take 1 . reverse . fst) conditions
T_WhileExpression id c l -> take 1 . reverse $ c
T_UntilExpression id c l -> take 1 . reverse $ c
_ -> []
prop_checkEchoWc3 = verify checkEchoWc "n=$(echo $foo | wc -c)"
checkEchoWc _ (T_Pipeline id _ [a, b]) =
when (acmd == ["echo", "${VAR}"]) $
case bcmd of
["wc", "-c"] -> countMsg
["wc", "-m"] -> countMsg
_ -> return ()
where
acmd = oversimplify a
bcmd = oversimplify b
countMsg = style id 2000 "See if you can use ${#variable} instead."
checkEchoWc _ _ = return ()
prop_checkEchoSed1 = verify checkEchoSed "FOO=$(echo \"$cow\" | sed 's/foo/bar/g')"
prop_checkEchoSed2 = verify checkEchoSed "rm $(echo $cow | sed -e 's,foo,bar,')"
checkEchoSed _ (T_Pipeline id _ [a, b]) =
when (acmd == ["echo", "${VAR}"]) $
case bcmd of
["sed", v] -> checkIn v
["sed", "-e", v] -> checkIn v
_ -> return ()
where
sedRe = mkRegex "^s(.)([^\n]*)g?$"
isSimpleSed s = fromMaybe False $ do
[first,rest] <- matchRegex sedRe s
let delimiters = filter (== (head first)) rest
guard $ length delimiters == 2
return True
acmd = oversimplify a
bcmd = oversimplify b
checkIn s =
when (isSimpleSed s) $
style id 2001 "See if you can use ${variable//search/replace} instead."
checkEchoSed _ _ = return ()
prop_checkPipedAssignment1 = verify checkPipedAssignment "A=ls | grep foo"
prop_checkPipedAssignment2 = verifyNot checkPipedAssignment "A=foo cmd | grep foo"
prop_checkPipedAssignment3 = verifyNot checkPipedAssignment "A=foo"
checkPipedAssignment _ (T_Pipeline _ _ (T_Redirecting _ _ (T_SimpleCommand id (_:_) []):_:_)) =
warn id 2036 "If you wanted to assign the output of the pipeline, use a=$(b | c) ."
checkPipedAssignment _ _ = return ()
prop_checkAssignAteCommand1 = verify checkAssignAteCommand "A=ls -l"
prop_checkAssignAteCommand2 = verify checkAssignAteCommand "A=ls --sort=$foo"
prop_checkAssignAteCommand3 = verify checkAssignAteCommand "A=cat foo | grep bar"
prop_checkAssignAteCommand4 = verifyNot checkAssignAteCommand "A=foo ls -l"
prop_checkAssignAteCommand5 = verifyNot checkAssignAteCommand "PAGER=cat grep bar"
checkAssignAteCommand _ (T_SimpleCommand id (T_Assignment _ _ _ _ assignmentTerm:[]) (firstWord:_)) =
when ("-" `isPrefixOf` concat (oversimplify firstWord) ||
isCommonCommand (getLiteralString assignmentTerm)
&& not (isCommonCommand (getLiteralString firstWord))) $
warn id 2037 "To assign the output of a command, use var=$(cmd) ."
where
isCommonCommand (Just s) = s `elem` commonCommands
isCommonCommand _ = False
checkAssignAteCommand _ _ = return ()
prop_checkArithmeticOpCommand1 = verify checkArithmeticOpCommand "i=i + 1"
prop_checkArithmeticOpCommand2 = verify checkArithmeticOpCommand "foo=bar * 2"
prop_checkArithmeticOpCommand3 = verifyNot checkArithmeticOpCommand "foo + opts"
checkArithmeticOpCommand _ (T_SimpleCommand id [T_Assignment {}] (firstWord:_)) =
fromMaybe (return ()) $ check <$> getGlobOrLiteralString firstWord
where
check op =
when (op `elem` ["+", "-", "*", "/"]) $
warn (getId firstWord) 2099 $
"Use $((..)) for arithmetics, e.g. i=$((i " ++ op ++ " 2))"
checkArithmeticOpCommand _ _ = return ()
prop_checkWrongArit = verify checkWrongArithmeticAssignment "i=i+1"
prop_checkWrongArit2 = verify checkWrongArithmeticAssignment "n=2; i=n*2"
checkWrongArithmeticAssignment params (T_SimpleCommand id (T_Assignment _ _ _ _ val:[]) []) =
fromMaybe (return ()) $ do
str <- getNormalString val
match <- matchRegex regex str
var <- match !!! 0
op <- match !!! 1
Map.lookup var references
return . warn (getId val) 2100 $
"Use $((..)) for arithmetics, e.g. i=$((i " ++ op ++ " 2))"
where
regex = mkRegex "^([_a-zA-Z][_a-zA-Z0-9]*)([+*-]).+$"
references = foldl (flip ($)) Map.empty (map insertRef $ variableFlow params)
insertRef (Assignment (_, _, name, _)) =
Map.insert name ()
insertRef _ = Prelude.id
getNormalString (T_NormalWord _ words) = do
parts <- foldl (liftM2 (\x y -> x ++ [y])) (Just []) $ map getLiterals words
return $ concat parts
getNormalString _ = Nothing
getLiterals (T_Literal _ s) = return s
getLiterals (T_Glob _ s) = return s
getLiterals _ = Nothing
checkWrongArithmeticAssignment _ _ = return ()
prop_checkUuoc1 = verify checkUuoc "cat foo | grep bar"
prop_checkUuoc2 = verifyNot checkUuoc "cat * | grep bar"
prop_checkUuoc3 = verify checkUuoc "cat $var | grep bar"
prop_checkUuoc4 = verifyNot checkUuoc "cat $var"
prop_checkUuoc5 = verifyNot checkUuoc "cat \"$@\""
prop_checkUuoc6 = verifyNot checkUuoc "cat -n | grep bar"
checkUuoc _ (T_Pipeline _ _ (T_Redirecting _ _ cmd:_:_)) =
checkCommand "cat" (const f) cmd
where
f [word] = unless (mayBecomeMultipleArgs word || isOption word) $
style (getId word) 2002 "Useless cat. Consider 'cmd < file | ..' or 'cmd file | ..' instead."
f _ = return ()
isOption word = "-" `isPrefixOf` onlyLiteralString word
checkUuoc _ _ = return ()
prop_checkPipePitfalls3 = verify checkPipePitfalls "ls | grep -v mp3"
prop_checkPipePitfalls4 = verifyNot checkPipePitfalls "find . -print0 | xargs -0 foo"
prop_checkPipePitfalls5 = verifyNot checkPipePitfalls "ls -N | foo"
prop_checkPipePitfalls6 = verify checkPipePitfalls "find . | xargs foo"
prop_checkPipePitfalls7 = verifyNot checkPipePitfalls "find . -printf '%s\\n' | xargs foo"
prop_checkPipePitfalls8 = verify checkPipePitfalls "foo | grep bar | wc -l"
prop_checkPipePitfalls9 = verifyNot checkPipePitfalls "foo | grep -o bar | wc -l"
checkPipePitfalls _ (T_Pipeline id _ commands) = do
for ["find", "xargs"] $
\(find:xargs:_) ->
let args = oversimplify xargs ++ oversimplify find
in
unless (any ($ args) [
hasShortParameter '0',
hasParameter "null",
hasParameter "print0",
hasParameter "printf"
]) $ warn (getId find) 2038
"Use -print0/-0 or -exec + to allow for non-alphanumeric filenames."
for ["?", "echo"] $
\(_:echo:_) -> info (getId echo) 2008 "echo doesn't read from stdin, are you sure you should be piping to it?"
for' ["ps", "grep"] $
\x -> info x 2009 "Consider using pgrep instead of grepping ps output."
for ["grep", "wc"] $
\(grep:wc:_) ->
let flags = fromMaybe [] $ map snd <$> getAllFlags <$> getCommand grep
in
unless (any (`elem` ["o", "only-matching"]) flags) $
style (getId grep) 2126 "Consider using grep -c instead of grep|wc."
didLs <- liftM or . sequence $ [
for' ["ls", "grep"] $
\x -> warn x 2010 "Don't use ls | grep. Use a glob or a for loop with a condition to allow non-alphanumeric filenames.",
for' ["ls", "xargs"] $
\x -> warn x 2011 "Use 'find .. -print0 | xargs -0 ..' or 'find .. -exec .. +' to allow non-alphanumeric filenames."
]
unless didLs $ do
for ["ls", "?"] $
\(ls:_) -> unless (hasShortParameter 'N' (oversimplify ls)) $
info (getId ls) 2012 "Use find instead of ls to better handle non-alphanumeric filenames."
return ()
where
for l f =
let indices = indexOfSublists l (map (headOrDefault "" . oversimplify) commands)
in do
mapM_ (f . (\ n -> take (length l) $ drop n commands)) indices
return . not . null $ indices
for' l f = for l (first f)
first func (x:_) = func (getId x)
first _ _ = return ()
hasShortParameter char = any (\x -> "-" `isPrefixOf` x && char `elem` x)
hasParameter string =
any (isPrefixOf string . dropWhile (== '-'))
checkPipePitfalls _ _ = return ()
indexOfSublists sub = f 0
where
f _ [] = []
f n a@(r:rest) =
let others = f (n+1) rest in
if match sub a
then n:others
else others
match ("?":r1) (_:r2) = match r1 r2
match (x1:r1) (x2:r2) | x1 == x2 = match r1 r2
match [] _ = True
match _ _ = False
prop_checkShebangParameters1 = verifyTree checkShebangParameters "#!/usr/bin/env bash -x\necho cow"
prop_checkShebangParameters2 = verifyNotTree checkShebangParameters "#! /bin/sh -l "
checkShebangParameters p (T_Annotation _ _ t) = checkShebangParameters p t
checkShebangParameters _ (T_Script id sb _) =
[makeComment ErrorC id 2096 "On most OS, shebangs can only specify a single parameter." | length (words sb) > 2]
prop_checkShebang1 = verifyNotTree checkShebang "#!/usr/bin/env bash -x\necho cow"
prop_checkShebang2 = verifyNotTree checkShebang "#! /bin/sh -l "
prop_checkShebang3 = verifyTree checkShebang "ls -l"
prop_checkShebang4 = verifyNotTree checkShebang "#shellcheck shell=sh\nfoo"
checkShebang params (T_Annotation _ list t) =
if any isOverride list then [] else checkShebang params t
where
isOverride (ShellOverride _) = True
isOverride _ = False
checkShebang params (T_Script id sb _) =
[makeComment ErrorC id 2148
"Tips depend on target shell and yours is unknown. Add a shebang."
| not (shellTypeSpecified params) && sb == "" ]
prop_checkBashisms = verify checkBashisms "while read a; do :; done < <(a)"
prop_checkBashisms2 = verify checkBashisms "[ foo -nt bar ]"
prop_checkBashisms3 = verify checkBashisms "echo $((i++))"
prop_checkBashisms4 = verify checkBashisms "rm !(*.hs)"
prop_checkBashisms5 = verify checkBashisms "source file"
prop_checkBashisms6 = verify checkBashisms "[ \"$a\" == 42 ]"
prop_checkBashisms7 = verify checkBashisms "echo ${var[1]}"
prop_checkBashisms8 = verify checkBashisms "echo ${!var[@]}"
prop_checkBashisms9 = verify checkBashisms "echo ${!var*}"
prop_checkBashisms10= verify checkBashisms "echo ${var:4:12}"
prop_checkBashisms11= verifyNot checkBashisms "echo ${var:-4}"
prop_checkBashisms12= verify checkBashisms "echo ${var//foo/bar}"
prop_checkBashisms13= verify checkBashisms "exec -c env"
prop_checkBashisms14= verify checkBashisms "echo -n \"Foo: \""
prop_checkBashisms15= verify checkBashisms "let n++"
prop_checkBashisms16= verify checkBashisms "echo $RANDOM"
prop_checkBashisms17= verify checkBashisms "echo $((RANDOM%6+1))"
prop_checkBashisms18= verify checkBashisms "foo &> /dev/null"
prop_checkBashisms19= verify checkBashisms "foo > file*.txt"
prop_checkBashisms20= verify checkBashisms "read -ra foo"
prop_checkBashisms21= verify checkBashisms "[ -a foo ]"
prop_checkBashisms22= verifyNot checkBashisms "[ foo -a bar ]"
prop_checkBashisms23= verify checkBashisms "trap mything ERR INT"
prop_checkBashisms24= verifyNot checkBashisms "trap mything INT TERM"
prop_checkBashisms25= verify checkBashisms "cat < /dev/tcp/host/123"
prop_checkBashisms26= verify checkBashisms "trap mything ERR SIGTERM"
prop_checkBashisms27= verify checkBashisms "echo *[^0-9]*"
prop_checkBashisms28= verify checkBashisms "exec {n}>&2"
prop_checkBashisms29= verify checkBashisms "echo ${!var}"
prop_checkBashisms30= verify checkBashisms "printf -v '%s' \"$1\""
prop_checkBashisms31= verify checkBashisms "printf '%q' \"$1\""
prop_checkBashisms32= verifyNot checkBashisms "#!/bin/dash\n[ foo -nt bar ]"
prop_checkBashisms33= verify checkBashisms "#!/bin/sh\necho -n foo"
prop_checkBashisms34= verifyNot checkBashisms "#!/bin/dash\necho -n foo"
prop_checkBashisms35= verifyNot checkBashisms "#!/bin/dash\nlocal foo"
prop_checkBashisms36= verifyNot checkBashisms "#!/bin/dash\nread -p foo -r bar"
prop_checkBashisms37= verifyNot checkBashisms "HOSTNAME=foo; echo $HOSTNAME"
prop_checkBashisms38= verify checkBashisms "RANDOM=9; echo $RANDOM"
prop_checkBashisms39= verify checkBashisms "foo-bar() { true; }"
prop_checkBashisms40= verify checkBashisms "echo $(<file)"
prop_checkBashisms41= verify checkBashisms "echo `<file`"
prop_checkBashisms42= verify checkBashisms "trap foo int"
prop_checkBashisms43= verify checkBashisms "trap foo sigint"
prop_checkBashisms44= verifyNot checkBashisms "#!/bin/dash\ntrap foo int"
prop_checkBashisms45= verifyNot checkBashisms "#!/bin/dash\ntrap foo INT"
prop_checkBashisms46= verify checkBashisms "#!/bin/dash\ntrap foo SIGINT"
prop_checkBashisms47= verify checkBashisms "#!/bin/dash\necho foo 42>/dev/null"
prop_checkBashisms48= verifyNot checkBashisms "#!/bin/dash\necho $LINENO"
prop_checkBashisms49= verify checkBashisms "#!/bin/dash\necho $MACHTYPE"
prop_checkBashisms50= verify checkBashisms "#!/bin/sh\ncmd >& file"
prop_checkBashisms51= verifyNot checkBashisms "#!/bin/sh\ncmd 2>&1"
prop_checkBashisms52= verifyNot checkBashisms "#!/bin/sh\ncmd >&2"
checkBashisms params = bashism
where
isDash = shellType params == Dash
warnMsg id s =
if isDash
then warn id 2169 $ "In dash, " ++ s ++ " not supported."
else warn id 2039 $ "In POSIX sh, " ++ s ++ " undefined."
bashism (T_ProcSub id _ _) = warnMsg id "process substitution is"
bashism (T_Extglob id _ _) = warnMsg id "extglob is"
bashism (T_DollarSingleQuoted id _) = warnMsg id "$'..' is"
bashism (T_DollarDoubleQuoted id _) = warnMsg id "$\"..\" is"
bashism (T_ForArithmetic id _ _ _ _) = warnMsg id "arithmetic for loops are"
bashism (T_Arithmetic id _) = warnMsg id "standalone ((..)) is"
bashism (T_DollarBracket id _) = warnMsg id "$[..] in place of $((..)) is"
bashism (T_SelectIn id _ _ _) = warnMsg id "select loops are"
bashism (T_BraceExpansion id _) = warnMsg id "brace expansion is"
bashism (T_Condition id DoubleBracket _) = warnMsg id "[[ ]] is"
bashism (T_HereString id _) = warnMsg id "here-strings are"
bashism (TC_Binary id SingleBracket op _ _)
| op `elem` [ "-nt", "-ef", "\\<", "\\>"] =
unless isDash $ warnMsg id $ op ++ " is"
bashism (TC_Binary id SingleBracket "==" _ _) =
warnMsg id "== in place of = is"
bashism (TC_Unary id _ "-a" _) =
warnMsg id "unary -a in place of -e is"
bashism (TA_Unary id op _)
| op `elem` [ "|++", "|--", "++|", "--|"] =
warnMsg id $ filter (/= '|') op ++ " is"
bashism (TA_Binary id "**" _ _) = warnMsg id "exponentials are"
bashism (T_FdRedirect id "&" (T_IoFile _ (T_Greater _) _)) = warnMsg id "&> is"
bashism (T_FdRedirect id "" (T_IoFile _ (T_GREATAND _) _)) = warnMsg id ">& is"
bashism (T_FdRedirect id ('{':_) _) = warnMsg id "named file descriptors are"
bashism (T_FdRedirect id num _)
| all isDigit num && length num > 1 = warnMsg id "FDs outside 0-9 are"
bashism (T_IoFile id _ word) | isNetworked =
warnMsg id "/dev/{tcp,udp} is"
where
file = onlyLiteralString word
isNetworked = any (`isPrefixOf` file) ["/dev/tcp", "/dev/udp"]
bashism (T_Glob id str) | "[^" `isInfixOf` str =
warnMsg id "^ in place of ! in glob bracket expressions is"
bashism t@(TA_Expansion id _) | isBashism =
warnMsg id $ fromJust str ++ " is"
where
str = getLiteralString t
isBashism = isJust str && isBashVariable (fromJust str)
bashism t@(T_DollarBraced id token) = do
mapM_ check expansion
when (isBashVariable var) $
warnMsg id $ var ++ " is"
where
str = bracedString t
var = getBracedReference str
check (regex, feature) =
when (isJust $ matchRegex regex str) $ warnMsg id feature
bashism t@(T_Pipe id "|&") =
warnMsg id "|& in place of 2>&1 | is"
bashism (T_Array id _) =
warnMsg id "arrays are"
bashism (T_IoFile id _ t) | isGlob t =
warnMsg id "redirecting to/from globs is"
bashism (T_CoProc id _ _) =
warnMsg id "coproc is"
bashism (T_Function id _ _ str _) | not (isVariableName str) =
warnMsg id "naming functions outside [a-zA-Z_][a-zA-Z0-9_]* is"
bashism (T_DollarExpansion id [x]) | isOnlyRedirection x =
warnMsg id "$(<file) to read files is"
bashism (T_Backticked id [x]) | isOnlyRedirection x =
warnMsg id "`<file` to read files is"
bashism t@(T_SimpleCommand _ _ (cmd:arg:_))
| t `isCommand` "echo" && "-" `isPrefixOf` argString =
unless ("--" `isPrefixOf` argString) $
if isDash
then
when (argString /= "-n") $
warnMsg (getId arg) "echo flags besides -n"
else
warnMsg (getId arg) "echo flags are"
where argString = concat $ oversimplify arg
bashism t@(T_SimpleCommand _ _ (cmd:arg:_))
| t `isCommand` "exec" && "-" `isPrefixOf` concat (oversimplify arg) =
warnMsg (getId arg) "exec flags are"
bashism t@(T_SimpleCommand id _ _)
| t `isCommand` "let" = warnMsg id "'let' is"
bashism t@(T_SimpleCommand id _ (cmd:rest)) =
let name = fromMaybe "" $ getCommandName t
flags = getLeadingFlags t
in do
when (name `elem` unsupportedCommands) $
warnMsg id $ "'" ++ name ++ "' is"
potentially $ do
allowed <- Map.lookup name allowedFlags
(word, flag) <- listToMaybe $
filter (\x -> (not . null . snd $ x) && snd x `notElem` allowed) flags
return . warnMsg (getId word) $ name ++ " -" ++ flag ++ " is"
when (name == "source") $ warnMsg id "'source' in place of '.' is"
when (name == "trap") $
let
check token = potentially $ do
str <- getLiteralString token
let upper = map toUpper str
return $ do
when (upper `elem` ["ERR", "DEBUG", "RETURN"]) $
warnMsg (getId token) $ "trapping " ++ str ++ " is"
when ("SIG" `isPrefixOf` upper) $
warnMsg (getId token)
"prefixing signal names with 'SIG' is"
when (not isDash && upper /= str) $
warnMsg (getId token)
"using lower/mixed case for signal names is"
in
mapM_ check (drop 1 rest)
when (name == "printf") $ potentially $ do
format <- rest !!! 0
let literal = onlyLiteralString format
guard $ "%q" `isInfixOf` literal
return $ warnMsg (getId format) "printf %q is"
where
unsupportedCommands = [
"let", "caller", "builtin", "complete", "compgen", "declare", "dirs", "disown",
"enable", "mapfile", "readarray", "pushd", "popd", "shopt", "suspend",
"typeset"
] ++ if not isDash then ["local", "type"] else []
allowedFlags = Map.fromList [
("read", if isDash then ["r", "p"] else ["r"]),
("ulimit", ["f"]),
("printf", []),
("exec", [])
]
bashism _ = return ()
varChars="_0-9a-zA-Z"
expansion = let re = mkRegex in [
(re $ "^![" ++ varChars ++ "]", "indirect expansion is"),
(re $ "^[" ++ varChars ++ "]+\\[.*\\]$", "array references are"),
(re $ "^![" ++ varChars ++ "]+\\[[*@]]$", "array key expansion is"),
(re $ "^![" ++ varChars ++ "]+[*@]$", "name matching prefixes are"),
(re $ "^[" ++ varChars ++ "]+:[^-=?+]", "string indexing is"),
(re $ "^[" ++ varChars ++ "]+(\\[.*\\])?/", "string replacement is")
]
bashVars = [
"LINENO", "OSTYPE", "MACHTYPE", "HOSTTYPE", "HOSTNAME",
"DIRSTACK", "EUID", "UID", "SHLVL", "PIPESTATUS", "SHELLOPTS"
]
bashDynamicVars = [ "RANDOM", "SECONDS" ]
dashVars = [ "LINENO" ]
isBashVariable var =
(var `elem` bashDynamicVars
|| var `elem` bashVars && not (isAssigned var))
&& not (isDash && var `elem` dashVars)
isAssigned var = any f (variableFlow params)
where
f x = case x of
Assignment (_, _, name, _) -> name == var
_ -> False
prop_checkForInQuoted = verify checkForInQuoted "for f in \"$(ls)\"; do echo foo; done"
prop_checkForInQuoted2 = verifyNot checkForInQuoted "for f in \"$@\"; do echo foo; done"
prop_checkForInQuoted2a = verifyNot checkForInQuoted "for f in *.mp3; do echo foo; done"
prop_checkForInQuoted2b = verify checkForInQuoted "for f in \"*.mp3\"; do echo foo; done"
prop_checkForInQuoted3 = verify checkForInQuoted "for f in 'find /'; do true; done"
prop_checkForInQuoted4 = verify checkForInQuoted "for f in 1,2,3; do true; done"
prop_checkForInQuoted4a = verifyNot checkForInQuoted "for f in foo{1,2,3}; do true; done"
prop_checkForInQuoted5 = verify checkForInQuoted "for f in ls; do true; done"
prop_checkForInQuoted6 = verifyNot checkForInQuoted "for f in \"${!arr}\"; do true; done"
checkForInQuoted _ (T_ForIn _ f [T_NormalWord _ [word@(T_DoubleQuoted id list)]] _) =
when (any (\x -> willSplit x && not (mayBecomeMultipleArgs x)) list
|| (liftM wouldHaveBeenGlob (getLiteralString word) == Just True)) $
err id 2066 "Since you double quoted this, it will not word split, and the loop will only run once."
checkForInQuoted _ (T_ForIn _ f [T_NormalWord _ [T_SingleQuoted id s]] _) =
warn id 2041 $ "This is a literal string. To run as a command, use $(" ++ s ++ ")."
checkForInQuoted _ (T_ForIn _ f [T_NormalWord _ [T_Literal id s]] _) =
if ',' `elem` s
then unless ('{' `elem` s) $
warn id 2042 "Use spaces, not commas, to separate loop elements."
else warn id 2043 $ "This loop will only run once, with " ++ f ++ "='" ++ s ++ "'."
checkForInQuoted _ _ = return ()
prop_checkForInCat1 = verify checkForInCat "for f in $(cat foo); do stuff; done"
prop_checkForInCat1a= verify checkForInCat "for f in `cat foo`; do stuff; done"
prop_checkForInCat2 = verify checkForInCat "for f in $(cat foo | grep lol); do stuff; done"
prop_checkForInCat2a= verify checkForInCat "for f in `cat foo | grep lol`; do stuff; done"
prop_checkForInCat3 = verifyNot checkForInCat "for f in $(cat foo | grep bar | wc -l); do stuff; done"
checkForInCat _ (T_ForIn _ f [T_NormalWord _ w] _) = mapM_ checkF w
where
checkF (T_DollarExpansion id [T_Pipeline _ _ r])
| all isLineBased r =
info id 2013 "To read lines rather than words, pipe/redirect to a 'while read' loop."
checkF (T_Backticked id cmds) = checkF (T_DollarExpansion id cmds)
checkF _ = return ()
isLineBased cmd = any (cmd `isCommand`)
["grep", "fgrep", "egrep", "sed", "cat", "awk", "cut", "sort"]
checkForInCat _ _ = return ()
prop_checkForInLs = verify checkForInLs "for f in $(ls *.mp3); do mplayer \"$f\"; done"
prop_checkForInLs2 = verify checkForInLs "for f in `ls *.mp3`; do mplayer \"$f\"; done"
prop_checkForInLs3 = verify checkForInLs "for f in `find / -name '*.mp3'`; do mplayer \"$f\"; done"
checkForInLs _ = try
where
try (T_ForIn _ f [T_NormalWord _ [T_DollarExpansion id [x]]] _) =
check id f x
try (T_ForIn _ f [T_NormalWord _ [T_Backticked id [x]]] _) =
check id f x
try _ = return ()
check id f x =
case oversimplify x of
("ls":n) ->
let warntype = if any ("-" `isPrefixOf`) n then warn else err in
warntype id 2045 "Iterating over ls output is fragile. Use globs."
("find":_) -> warn id 2044 "For loops over find output are fragile. Use find -exec or a while read loop."
_ -> return ()
prop_checkFindExec1 = verify checkFindExec "find / -name '*.php' -exec rm {};"
prop_checkFindExec2 = verify checkFindExec "find / -exec touch {} && ls {} \\;"
prop_checkFindExec3 = verify checkFindExec "find / -execdir cat {} | grep lol +"
prop_checkFindExec4 = verifyNot checkFindExec "find / -name '*.php' -exec foo {} +"
prop_checkFindExec5 = verifyNot checkFindExec "find / -execdir bash -c 'a && b' \\;"
prop_checkFindExec6 = verify checkFindExec "find / -type d -execdir rm *.jpg \\;"
checkFindExec _ cmd@(T_SimpleCommand _ _ t@(h:r)) | cmd `isCommand` "find" = do
c <- broken r False
when c $
let wordId = getId $ last t in
err wordId 2067 "Missing ';' or + terminating -exec. You can't use |/||/&&, and ';' has to be a separate, quoted argument."
where
broken [] v = return v
broken (w:r) v = do
when v (mapM_ warnFor $ fromWord w)
case getLiteralString w of
Just "-exec" -> broken r True
Just "-execdir" -> broken r True
Just "+" -> broken r False
Just ";" -> broken r False
_ -> broken r v
shouldWarn x =
case x of
T_DollarExpansion _ _ -> True
T_Backticked _ _ -> True
T_Glob _ _ -> True
T_Extglob {} -> True
_ -> False
warnFor x =
when(shouldWarn x) $
info (getId x) 2014 "This will expand once before find runs, not per file found."
fromWord (T_NormalWord _ l) = l
fromWord _ = []
checkFindExec _ _ = return ()
prop_checkUnquotedExpansions1 = verify checkUnquotedExpansions "rm $(ls)"
prop_checkUnquotedExpansions1a= verify checkUnquotedExpansions "rm `ls`"
prop_checkUnquotedExpansions2 = verify checkUnquotedExpansions "rm foo$(date)"
prop_checkUnquotedExpansions3 = verify checkUnquotedExpansions "[ $(foo) == cow ]"
prop_checkUnquotedExpansions3a= verify checkUnquotedExpansions "[ ! $(foo) ]"
prop_checkUnquotedExpansions4 = verifyNot checkUnquotedExpansions "[[ $(foo) == cow ]]"
prop_checkUnquotedExpansions5 = verifyNot checkUnquotedExpansions "for f in $(cmd); do echo $f; done"
prop_checkUnquotedExpansions6 = verifyNot checkUnquotedExpansions "$(cmd)"
prop_checkUnquotedExpansions7 = verifyNot checkUnquotedExpansions "cat << foo\n$(ls)\nfoo"
prop_checkUnquotedExpansions8 = verifyNot checkUnquotedExpansions "set -- $(seq 1 4)"
prop_checkUnquotedExpansions9 = verifyNot checkUnquotedExpansions "echo foo `# inline comment`"
checkUnquotedExpansions params =
check
where
check t@(T_DollarExpansion _ c) = examine t c
check t@(T_Backticked _ c) = examine t c
check t@(T_DollarBraceCommandExpansion _ c) = examine t c
check _ = return ()
tree = parentMap params
examine t contents =
unless (null contents || shouldBeSplit t || isQuoteFree tree t || usedAsCommandName tree t) $
warn (getId t) 2046 "Quote this to prevent word splitting."
shouldBeSplit t =
getCommandNameFromExpansion t == Just "seq"
prop_checkRedirectToSame = verify checkRedirectToSame "cat foo > foo"
prop_checkRedirectToSame2 = verify checkRedirectToSame "cat lol | sed -e 's/a/b/g' > lol"
prop_checkRedirectToSame3 = verifyNot checkRedirectToSame "cat lol | sed -e 's/a/b/g' > foo.bar && mv foo.bar lol"
prop_checkRedirectToSame4 = verifyNot checkRedirectToSame "foo /dev/null > /dev/null"
prop_checkRedirectToSame5 = verifyNot checkRedirectToSame "foo > bar 2> bar"
prop_checkRedirectToSame6 = verifyNot checkRedirectToSame "echo foo > foo"
prop_checkRedirectToSame7 = verifyNot checkRedirectToSame "sed 's/foo/bar/g' file | sponge file"
checkRedirectToSame params s@(T_Pipeline _ _ list) =
mapM_ (\l -> (mapM_ (\x -> doAnalysis (checkOccurrences x) l) (getAllRedirs list))) list
where
note x = makeComment InfoC x 2094
"Make sure not to read and write the same file in the same pipeline."
checkOccurrences t@(T_NormalWord exceptId x) u@(T_NormalWord newId y) =
when (exceptId /= newId
&& x == y
&& not (isOutput t && isOutput u)
&& not (special t)
&& not (any isHarmlessCommand [t,u])) $ do
addComment $ note newId
addComment $ note exceptId
checkOccurrences _ _ = return ()
getAllRedirs = concatMap (\t ->
case t of
T_Redirecting _ ls _ -> concatMap getRedirs ls
_ -> [])
getRedirs (T_FdRedirect _ _ (T_IoFile _ op file)) =
case op of T_Greater _ -> [file]
T_Less _ -> [file]
T_DGREAT _ -> [file]
_ -> []
getRedirs _ = []
special x = "/dev/" `isPrefixOf` concat (oversimplify x)
isOutput t =
case drop 1 $ getPath (parentMap params) t of
T_IoFile _ op _:_ ->
case op of
T_Greater _ -> True
T_DGREAT _ -> True
_ -> False
_ -> False
isHarmlessCommand arg = fromMaybe False $ do
cmd <- getClosestCommand (parentMap params) arg
name <- getCommandBasename cmd
return $ name `elem` ["echo", "printf", "sponge"]
checkRedirectToSame _ _ = return ()
prop_checkShorthandIf = verify checkShorthandIf "[[ ! -z file ]] && scp file host || rm file"
prop_checkShorthandIf2 = verifyNot checkShorthandIf "[[ ! -z file ]] && { scp file host || echo 'Eek'; }"
prop_checkShorthandIf3 = verifyNot checkShorthandIf "foo && bar || echo baz"
prop_checkShorthandIf4 = verifyNot checkShorthandIf "foo && a=b || a=c"
prop_checkShorthandIf5 = verifyNot checkShorthandIf "foo && rm || printf b"
prop_checkShorthandIf6 = verifyNot checkShorthandIf "if foo && bar || baz; then true; fi"
prop_checkShorthandIf7 = verifyNot checkShorthandIf "while foo && bar || baz; do true; done"
prop_checkShorthandIf8 = verify checkShorthandIf "if true; then foo && bar || baz; fi"
checkShorthandIf params x@(T_AndIf id _ (T_OrIf _ _ (T_Pipeline _ _ t)))
| not (isOk t || inCondition) =
info id 2015 "Note that A && B || C is not if-then-else. C may run when A is true."
where
isOk [t] = isAssignment t || fromMaybe False (do
name <- getCommandBasename t
return $ name `elem` ["echo", "exit", "return", "printf"])
isOk _ = False
inCondition = isCondition $ getPath (parentMap params) x
checkShorthandIf _ _ = return ()
prop_checkDollarStar = verify checkDollarStar "for f in $*; do ..; done"
prop_checkDollarStar2 = verifyNot checkDollarStar "a=$*"
checkDollarStar p t@(T_NormalWord _ [b@(T_DollarBraced id _)])
| bracedString b == "*" =
unless isAssigned $
warn id 2048 "Use \"$@\" (with quotes) to prevent whitespace problems."
where
path = getPath (parentMap p) t
isAssigned = any isAssignment . take 2 $ path
checkDollarStar _ _ = return ()
prop_checkUnquotedDollarAt = verify checkUnquotedDollarAt "ls $@"
prop_checkUnquotedDollarAt1= verifyNot checkUnquotedDollarAt "ls ${#@}"
prop_checkUnquotedDollarAt2 = verify checkUnquotedDollarAt "ls ${foo[@]}"
prop_checkUnquotedDollarAt3 = verifyNot checkUnquotedDollarAt "ls ${#foo[@]}"
prop_checkUnquotedDollarAt4 = verifyNot checkUnquotedDollarAt "ls \"$@\""
prop_checkUnquotedDollarAt5 = verifyNot checkUnquotedDollarAt "ls ${foo/@/ at }"
prop_checkUnquotedDollarAt6 = verifyNot checkUnquotedDollarAt "a=$@"
prop_checkUnquotedDollarAt7 = verify checkUnquotedDollarAt "for f in ${var[@]}; do true; done"
prop_checkUnquotedDollarAt8 = verifyNot checkUnquotedDollarAt "echo \"${args[@]:+${args[@]}}\""
prop_checkUnquotedDollarAt9 = verifyNot checkUnquotedDollarAt "echo ${args[@]:+\"${args[@]}\"}"
checkUnquotedDollarAt p word@(T_NormalWord _ parts) | not $ isStrictlyQuoteFree (parentMap p) word =
forM_ (take 1 $ filter isArrayExpansion parts) $ \x ->
unless (isAlternative x) $
err (getId x) 2068
"Double quote array expansions to avoid re-splitting elements."
where
isAlternative b@(T_DollarBraced _ t) = ":+" `isInfixOf` bracedString b
isAlternative _ = False
checkUnquotedDollarAt _ _ = return ()
prop_checkConcatenatedDollarAt1 = verify checkConcatenatedDollarAt "echo \"foo$@\""
prop_checkConcatenatedDollarAt2 = verify checkConcatenatedDollarAt "echo ${arr[@]}lol"
prop_checkConcatenatedDollarAt3 = verify checkConcatenatedDollarAt "echo $a$@"
prop_checkConcatenatedDollarAt4 = verifyNot checkConcatenatedDollarAt "echo $@"
prop_checkConcatenatedDollarAt5 = verifyNot checkConcatenatedDollarAt "echo \"${arr[@]}\""
checkConcatenatedDollarAt p word@(T_NormalWord {})
| not $ isQuoteFree (parentMap p) word =
unless (null $ drop 1 parts) $
mapM_ for array
where
parts = getWordParts word
array = take 1 $ filter isArrayExpansion parts
for t = err (getId t) 2145 "Argument mixes string and array. Use * or separate argument."
checkConcatenatedDollarAt _ _ = return ()
prop_checkArrayAsString1 = verify checkArrayAsString "a=$@"
prop_checkArrayAsString2 = verify checkArrayAsString "a=\"${arr[@]}\""
prop_checkArrayAsString3 = verify checkArrayAsString "a=*.png"
prop_checkArrayAsString4 = verify checkArrayAsString "a={1..10}"
prop_checkArrayAsString5 = verifyNot checkArrayAsString "a='*.gif'"
prop_checkArrayAsString6 = verifyNot checkArrayAsString "a=$*"
prop_checkArrayAsString7 = verifyNot checkArrayAsString "a=( $@ )"
checkArrayAsString _ (T_Assignment id _ _ _ word) =
if willConcatInAssignment word
then
warn (getId word) 2124
"Assigning an array to a string! Assign as array, or use * instead of @ to concatenate."
else
when (willBecomeMultipleArgs word) $
warn (getId word) 2125
"Brace expansions and globs are literal in assignments. Quote it or use an array."
checkArrayAsString _ _ = return ()
prop_checkArrayWithoutIndex1 = verifyTree checkArrayWithoutIndex "foo=(a b); echo $foo"
prop_checkArrayWithoutIndex2 = verifyNotTree checkArrayWithoutIndex "foo='bar baz'; foo=($foo); echo ${foo[0]}"
prop_checkArrayWithoutIndex3 = verifyTree checkArrayWithoutIndex "coproc foo while true; do echo cow; done; echo $foo"
prop_checkArrayWithoutIndex4 = verifyTree checkArrayWithoutIndex "coproc tail -f log; echo $COPROC"
prop_checkArrayWithoutIndex5 = verifyTree checkArrayWithoutIndex "a[0]=foo; echo $a"
prop_checkArrayWithoutIndex6 = verifyTree checkArrayWithoutIndex "echo $PIPESTATUS"
prop_checkArrayWithoutIndex7 = verifyTree checkArrayWithoutIndex "a=(a b); a+=c"
prop_checkArrayWithoutIndex8 = verifyTree checkArrayWithoutIndex "declare -a foo; foo=bar;"
checkArrayWithoutIndex params _ =
doVariableFlowAnalysis readF writeF defaultMap (variableFlow params)
where
defaultMap = Map.fromList $ map (\x -> (x,())) arrayVariables
readF _ (T_DollarBraced id token) _ = do
map <- get
return . maybeToList $ do
name <- getLiteralString token
assigned <- Map.lookup name map
return $ makeComment WarningC id 2128
"Expanding an array without an index only gives the first element."
readF _ _ _ = return []
writeF _ (T_Assignment id mode name [] _) _ (DataString _) = do
isArray <- gets (isJust . Map.lookup name)
return $ if not isArray then [] else
case mode of
Assign -> [makeComment WarningC id 2178 "Variable was used as an array but is now assigned a string."]
Append -> [makeComment WarningC id 2179 "Use array+=(\"item\") to append items to an array."]
writeF _ t name (DataArray _) = do
modify (Map.insert name ())
return []
writeF _ expr name _ = do
if isIndexed expr
then modify (Map.insert name ())
else modify (Map.delete name)
return []
isIndexed expr =
case expr of
T_Assignment _ _ _ (_:_) _ -> True
_ -> False
prop_checkStderrRedirect = verify checkStderrRedirect "test 2>&1 > cow"
prop_checkStderrRedirect2 = verifyNot checkStderrRedirect "test > cow 2>&1"
prop_checkStderrRedirect3 = verifyNot checkStderrRedirect "test 2>&1 > file | grep stderr"
prop_checkStderrRedirect4 = verifyNot checkStderrRedirect "errors=$(test 2>&1 > file)"
prop_checkStderrRedirect5 = verifyNot checkStderrRedirect "read < <(test 2>&1 > file)"
prop_checkStderrRedirect6 = verify checkStderrRedirect "foo | bar 2>&1 > /dev/null"
checkStderrRedirect params redir@(T_Redirecting _ [
T_FdRedirect id "2" (T_IoDuplicate _ (T_GREATAND _) "1"),
T_FdRedirect _ _ (T_IoFile _ op _)
] _) = case op of
T_Greater _ -> error
T_DGREAT _ -> error
_ -> return ()
where
usesOutput t =
case t of
(T_Pipeline _ _ list) -> length list > 1 && not (isParentOf (parentMap params) (last list) redir)
(T_ProcSub {}) -> True
(T_DollarExpansion {}) -> True
(T_Backticked {}) -> True
_ -> False
isCaptured = any usesOutput $ getPath (parentMap params) redir
error = unless isCaptured $
err id 2069 "The order of the 2>&1 and the redirect matters. The 2>&1 has to be last."
checkStderrRedirect _ _ = return ()
lt x = trace ("Tracing " ++ show x) x
ltt t = trace ("Tracing " ++ show t)
prop_checkSingleQuotedVariables = verify checkSingleQuotedVariables "echo '$foo'"
prop_checkSingleQuotedVariables2 = verify checkSingleQuotedVariables "echo 'lol$1.jpg'"
prop_checkSingleQuotedVariables3 = verifyNot checkSingleQuotedVariables "sed 's/foo$/bar/'"
prop_checkSingleQuotedVariables3a= verify checkSingleQuotedVariables "sed 's/${foo}/bar/'"
prop_checkSingleQuotedVariables3b= verify checkSingleQuotedVariables "sed 's/$(echo cow)/bar/'"
prop_checkSingleQuotedVariables3c= verify checkSingleQuotedVariables "sed 's/$((1+foo))/bar/'"
prop_checkSingleQuotedVariables4 = verifyNot checkSingleQuotedVariables "awk '{print $1}'"
prop_checkSingleQuotedVariables5 = verifyNot checkSingleQuotedVariables "trap 'echo $SECONDS' EXIT"
prop_checkSingleQuotedVariables6 = verifyNot checkSingleQuotedVariables "sed -n '$p'"
prop_checkSingleQuotedVariables6a= verify checkSingleQuotedVariables "sed -n '$pattern'"
prop_checkSingleQuotedVariables7 = verifyNot checkSingleQuotedVariables "PS1='$PWD \\$ '"
prop_checkSingleQuotedVariables8 = verify checkSingleQuotedVariables "find . -exec echo '$1' {} +"
prop_checkSingleQuotedVariables9 = verifyNot checkSingleQuotedVariables "find . -exec awk '{print $1}' {} \\;"
prop_checkSingleQuotedVariables10= verify checkSingleQuotedVariables "echo '`pwd`'"
prop_checkSingleQuotedVariables11= verifyNot checkSingleQuotedVariables "sed '${/lol/d}'"
prop_checkSingleQuotedVariables12= verifyNot checkSingleQuotedVariables "eval 'echo $1'"
checkSingleQuotedVariables params t@(T_SingleQuoted id s) =
when (s `matches` re) $
if "sed" == commandName
then unless (s `matches` sedContra) showMessage
else unless isProbablyOk showMessage
where
parents = parentMap params
showMessage = info id 2016
"Expressions don't expand in single quotes, use double quotes for that."
commandName = fromMaybe "" $ do
cmd <- getClosestCommand parents t
name <- getCommandBasename cmd
return $ if name == "find" then getFindCommand cmd else name
isProbablyOk =
any isOkAssignment (take 3 $ getPath parents t)
|| commandName `elem` [
"trap"
,"sh"
,"bash"
,"ksh"
,"zsh"
,"ssh"
,"eval"
,"xprop"
,"alias"
,"sudo"
,"dpkg-query"
,"jq"
]
|| "awk" `isSuffixOf` commandName
|| "perl" `isPrefixOf` commandName
commonlyQuoted = ["PS1", "PS2", "PS3", "PS4", "PROMPT_COMMAND"]
isOkAssignment t =
case t of
T_Assignment _ _ name _ _ -> name `elem` commonlyQuoted
otherwise -> False
re = mkRegex "\\$[{(0-9a-zA-Z_]|`.*`"
sedContra = mkRegex "\\$[{dpsaic]($|[^a-zA-Z])"
getFindCommand (T_SimpleCommand _ _ words) =
let list = map getLiteralString words
cmd = dropWhile (\x -> x /= Just "-exec" && x /= Just "-execdir") list
in
case cmd of
(flag:cmd:rest) -> fromMaybe "find" cmd
_ -> "find"
getFindCommand (T_Redirecting _ _ cmd) = getFindCommand cmd
getFindCommand _ = "find"
checkSingleQuotedVariables _ _ = return ()
prop_checkUnquotedN = verify checkUnquotedN "if [ -n $foo ]; then echo cow; fi"
prop_checkUnquotedN2 = verify checkUnquotedN "[ -n $cow ]"
prop_checkUnquotedN3 = verifyNot checkUnquotedN "[[ -n $foo ]] && echo cow"
prop_checkUnquotedN4 = verify checkUnquotedN "[ -n $cow -o -t 1 ]"
checkUnquotedN _ (TC_Unary _ SingleBracket "-n" (T_NormalWord id [t])) | willSplit t =
err id 2070 "-n doesn't work with unquoted arguments. Quote or use [[ ]]."
checkUnquotedN _ _ = return ()
prop_checkNumberComparisons1 = verify checkNumberComparisons "[[ $foo < 3 ]]"
prop_checkNumberComparisons2 = verify checkNumberComparisons "[[ 0 >= $(cmd) ]]"
prop_checkNumberComparisons3 = verifyNot checkNumberComparisons "[[ $foo ]] > 3"
prop_checkNumberComparisons4 = verify checkNumberComparisons "[[ $foo > 2.72 ]]"
prop_checkNumberComparisons5 = verify checkNumberComparisons "[[ $foo -le 2.72 ]]"
prop_checkNumberComparisons6 = verify checkNumberComparisons "[[ 3.14 -eq $foo ]]"
prop_checkNumberComparisons7 = verifyNot checkNumberComparisons "[[ 3.14 == $foo ]]"
prop_checkNumberComparisons8 = verify checkNumberComparisons "[ foo <= bar ]"
prop_checkNumberComparisons9 = verify checkNumberComparisons "[ foo \\>= bar ]"
prop_checkNumberComparisons11= verify checkNumberComparisons "[ $foo -eq 'N' ]"
prop_checkNumberComparisons12= verify checkNumberComparisons "[ x$foo -gt x${N} ]"
checkNumberComparisons params (TC_Binary id typ op lhs rhs) = do
if isNum lhs && not (isNonNum rhs)
|| isNum rhs && not (isNonNum lhs)
then do
when (isLtGt op) $
err id 2071 $
op ++ " is for string comparisons. Use " ++ eqv op ++ " instead."
when (isLeGe op) $
err id 2071 $ op ++ " is not a valid operator. " ++
"Use " ++ eqv op ++ " ."
else do
when (isLeGe op || isLtGt op) $
mapM_ checkDecimals [lhs, rhs]
when (isLeGe op) $
err id 2122 $ op ++ " is not a valid operator. " ++
"Use '! a " ++ invert op ++ " b' instead."
when (op `elem` ["-lt", "-gt", "-le", "-ge", "-eq"]) $ do
mapM_ checkDecimals [lhs, rhs]
when (typ == SingleBracket) $
checkStrings [lhs, rhs]
where
isLtGt = flip elem ["<", "\\<", ">", "\\>"]
isLeGe = flip elem ["<=", "\\<=", ">=", "\\>="]
checkDecimals hs =
when (isFraction hs && not (hasFloatingPoint params)) $
err (getId hs) 2072 decimalError
decimalError = "Decimals are not supported. " ++
"Either use integers only, or use bc or awk to compare."
checkStrings hs =
mapM_ stringError . take 1 . filter isNonNum $ hs
isNonNum t = fromMaybe False $ do
s <- getLiteralStringExt (const $ return "") t
return . not . all numChar $ s
numChar x = isDigit x || x `elem` "+-. "
stringError t = err (getId t) 2170 $
"Numerical " ++ op ++ " does not dereference in [..]. Expand or use string operator."
isNum t =
case oversimplify t of
[v] -> all isDigit v
_ -> False
isFraction t =
case oversimplify t of
[v] -> isJust $ matchRegex floatRegex v
_ -> False
eqv ('\\':s) = eqv s
eqv "<" = "-lt"
eqv ">" = "-gt"
eqv "<=" = "-le"
eqv ">=" = "-ge"
eqv _ = "the numerical equivalent"
esc = if typ == SingleBracket then "\\" else ""
seqv "-ge" = "! a " ++ esc ++ "< b"
seqv "-gt" = esc ++ ">"
seqv "-le" = "! a " ++ esc ++ "> b"
seqv "-lt" = esc ++ "<"
seqv "-eq" = "="
seqv "-ne" = "!="
seqv _ = "the string equivalent"
invert ('\\':s) = invert s
invert "<=" = ">"
invert ">=" = "<"
floatRegex = mkRegex "^[0-9]+\\.[0-9]+$"
checkNumberComparisons _ _ = return ()
prop_checkSingleBracketOperators1 = verify checkSingleBracketOperators "[ test =~ foo ]"
prop_checkSingleBracketOperators2 = verify checkSingleBracketOperators "[ $foo > $bar ]"
prop_checkSingleBracketOperators3 = verifyNot checkSingleBracketOperators "[[ foo < bar ]]"
prop_checkSingleBracketOperators5 = verify checkSingleBracketOperators "until [ $n <= $z ]; do echo foo; done"
prop_checkSingleBracketOperators6 = verifyNot checkSingleBracketOperators "[ $foo '>' $bar ]"
checkSingleBracketOperators _ (TC_Binary id typ op lhs rhs)
| typ == SingleBracket && op `elem` ["<", ">", "<=", ">="] =
err id 2073 $ "Can't use " ++ op ++" in [ ]. Escape it or use [[..]]."
checkSingleBracketOperators _ (TC_Binary id typ op lhs rhs)
| typ == SingleBracket && op == "=~" =
err id 2074 $ "Can't use " ++ op ++" in [ ]. Use [[..]] instead."
checkSingleBracketOperators _ _ = return ()
prop_checkDoubleBracketOperators1 = verify checkDoubleBracketOperators "[[ 3 \\< 4 ]]"
prop_checkDoubleBracketOperators3 = verifyNot checkDoubleBracketOperators "[[ foo < bar ]]"
checkDoubleBracketOperators _ x@(TC_Binary id typ op lhs rhs)
| typ == DoubleBracket && op `elem` ["\\<", "\\>", "\\<=", "\\>="] =
err id 2075 $ "Escaping " ++ op ++" is required in [..], but invalid in [[..]]"
checkDoubleBracketOperators _ _ = return ()
prop_checkConditionalAndOrs1 = verify checkConditionalAndOrs "[ foo && bar ]"
prop_checkConditionalAndOrs2 = verify checkConditionalAndOrs "[[ foo -o bar ]]"
prop_checkConditionalAndOrs3 = verifyNot checkConditionalAndOrs "[[ foo || bar ]]"
prop_checkConditionalAndOrs4 = verify checkConditionalAndOrs "[ foo -a bar ]"
prop_checkConditionalAndOrs5 = verify checkConditionalAndOrs "[ -z 3 -o a = b ]"
checkConditionalAndOrs _ t =
case t of
(TC_And id SingleBracket "&&" _ _) ->
err id 2107 "Instead of [ a && b ], use [ a ] && [ b ]."
(TC_And id DoubleBracket "-a" _ _) ->
err id 2108 "In [[..]], use && instead of -a."
(TC_Or id SingleBracket "||" _ _) ->
err id 2109 "Instead of [ a || b ], use [ a ] || [ b ]."
(TC_Or id DoubleBracket "-o" _ _) ->
err id 2110 "In [[..]], use || instead of -o."
(TC_And id SingleBracket "-a" _ _) ->
warn id 2166 "Prefer [ p ] && [ q ] as [ p -a q ] is not well defined."
(TC_Or id SingleBracket "-o" _ _) ->
warn id 2166 "Prefer [ p ] || [ q ] as [ p -o q ] is not well defined."
otherwise -> return ()
prop_checkQuotedCondRegex1 = verify checkQuotedCondRegex "[[ $foo =~ \"bar.*\" ]]"
prop_checkQuotedCondRegex2 = verify checkQuotedCondRegex "[[ $foo =~ '(cow|bar)' ]]"
prop_checkQuotedCondRegex3 = verifyNot checkQuotedCondRegex "[[ $foo =~ $foo ]]"
prop_checkQuotedCondRegex4 = verifyNot checkQuotedCondRegex "[[ $foo =~ \"bar\" ]]"
prop_checkQuotedCondRegex5 = verifyNot checkQuotedCondRegex "[[ $foo =~ 'cow bar' ]]"
checkQuotedCondRegex _ (TC_Binary _ _ "=~" _ rhs) =
case rhs of
T_NormalWord id [T_DoubleQuoted _ _] -> error rhs
T_NormalWord id [T_SingleQuoted _ _] -> error rhs
_ -> return ()
where
error t =
unless (isConstantNonRe t) $
err (getId t) 2076
"Don't quote rhs of =~, it'll match literally rather than as a regex."
re = mkRegex "[][*.+()]"
hasMetachars s = s `matches` re
isConstantNonRe t = fromMaybe False $ do
s <- getLiteralString t
return . not $ hasMetachars s
checkQuotedCondRegex _ _ = return ()
prop_checkGlobbedRegex1 = verify checkGlobbedRegex "[[ $foo =~ *foo* ]]"
prop_checkGlobbedRegex2 = verify checkGlobbedRegex "[[ $foo =~ f* ]]"
prop_checkGlobbedRegex2a = verify checkGlobbedRegex "[[ $foo =~ \\#* ]]"
prop_checkGlobbedRegex3 = verifyNot checkGlobbedRegex "[[ $foo =~ $foo ]]"
prop_checkGlobbedRegex4 = verifyNot checkGlobbedRegex "[[ $foo =~ ^c.* ]]"
checkGlobbedRegex _ (TC_Binary _ DoubleBracket "=~" _ rhs) =
let s = concat $ oversimplify rhs in
when (isConfusedGlobRegex s) $
warn (getId rhs) 2049 "=~ is for regex. Use == for globs."
checkGlobbedRegex _ _ = return ()
prop_checkConstantIfs1 = verify checkConstantIfs "[[ foo != bar ]]"
prop_checkConstantIfs2a= verify checkConstantIfs "[ n -le 4 ]"
prop_checkConstantIfs2b= verifyNot checkConstantIfs "[[ n -le 4 ]]"
prop_checkConstantIfs3 = verify checkConstantIfs "[[ $n -le 4 && n != 2 ]]"
prop_checkConstantIfs4 = verifyNot checkConstantIfs "[[ $n -le 3 ]]"
prop_checkConstantIfs5 = verifyNot checkConstantIfs "[[ $n -le $n ]]"
prop_checkConstantIfs6 = verifyNot checkConstantIfs "[[ a -ot b ]]"
prop_checkConstantIfs7 = verifyNot checkConstantIfs "[ a -nt b ]"
prop_checkConstantIfs8 = verifyNot checkConstantIfs "[[ ~foo == '~foo' ]]"
checkConstantIfs _ (TC_Binary id typ op lhs rhs) | not isDynamic =
when (isConstant lhs && isConstant rhs) $
warn id 2050 "This expression is constant. Did you forget the $ on a variable?"
where
isDynamic =
op `elem` [ "-lt", "-gt", "-le", "-ge", "-eq", "-ne" ]
&& typ == DoubleBracket
|| op `elem` [ "-nt", "-ot", "-ef"]
checkConstantIfs _ _ = return ()
prop_checkLiteralBreakingTest = verify checkLiteralBreakingTest "[[ a==$foo ]]"
prop_checkLiteralBreakingTest2 = verify checkLiteralBreakingTest "[ $foo=3 ]"
prop_checkLiteralBreakingTest3 = verify checkLiteralBreakingTest "[ $foo!=3 ]"
prop_checkLiteralBreakingTest4 = verify checkLiteralBreakingTest "[ \"$(ls) \" ]"
prop_checkLiteralBreakingTest5 = verify checkLiteralBreakingTest "[ -n \"$(true) \" ]"
prop_checkLiteralBreakingTest6 = verify checkLiteralBreakingTest "[ -z $(true)z ]"
prop_checkLiteralBreakingTest7 = verifyNot checkLiteralBreakingTest "[ -z $(true) ]"
prop_checkLiteralBreakingTest8 = verifyNot checkLiteralBreakingTest "[ $(true)$(true) ]"
prop_checkLiteralBreakingTest10 = verify checkLiteralBreakingTest "[ -z foo ]"
checkLiteralBreakingTest _ t = potentially $
case t of
(TC_Noary _ _ w@(T_NormalWord _ l)) -> do
guard . not $ isConstant w
comparisonWarning l `mplus` tautologyWarning w "Argument to implicit -n is always true due to literal strings."
(TC_Unary _ _ op w@(T_NormalWord _ l)) ->
case op of
"-n" -> tautologyWarning w "Argument to -n is always true due to literal strings."
"-z" -> tautologyWarning w "Argument to -z is always false due to literal strings."
_ -> fail "not relevant"
_ -> fail "not my problem"
where
hasEquals = matchToken ('=' `elem`)
isNonEmpty = matchToken (not . null)
matchToken m t = isJust $ do
str <- getLiteralString t
guard $ m str
return ()
comparisonWarning list = do
token <- listToMaybe $ filter hasEquals list
return $ err (getId token) 2077 "You need spaces around the comparison operator."
tautologyWarning t s = do
token <- listToMaybe $ filter isNonEmpty $ getWordParts t
return $ err (getId token) 2157 s
prop_checkConstantNoary = verify checkConstantNoary "[[ '$(foo)' ]]"
prop_checkConstantNoary2 = verify checkConstantNoary "[ \"-f lol\" ]"
prop_checkConstantNoary3 = verify checkConstantNoary "[[ cmd ]]"
prop_checkConstantNoary4 = verify checkConstantNoary "[[ ! cmd ]]"
prop_checkConstantNoary5 = verify checkConstantNoary "[[ true ]]"
prop_checkConstantNoary6 = verify checkConstantNoary "[ 1 ]"
prop_checkConstantNoary7 = verify checkConstantNoary "[ false ]"
checkConstantNoary _ (TC_Noary _ _ t) | isConstant t =
case fromMaybe "" $ getLiteralString t of
"false" -> err (getId t) 2158 "[ false ] is true. Remove the brackets."
"0" -> err (getId t) 2159 "[ 0 ] is true. Use 'false' instead."
"true" -> style (getId t) 2160 "Instead of '[ true ]', just use 'true'."
"1" -> style (getId t) 2161 "Instead of '[ 1 ]', use 'true'."
_ -> err (getId t) 2078 "This expression is constant. Did you forget a $ somewhere?"
where
string = fromMaybe "" $ getLiteralString t
checkConstantNoary _ _ = return ()
prop_checkBraceExpansionVars1 = verify checkBraceExpansionVars "echo {1..$n}"
prop_checkBraceExpansionVars2 = verifyNot checkBraceExpansionVars "echo {1,3,$n}"
prop_checkBraceExpansionVars3 = verify checkBraceExpansionVars "eval echo DSC{0001..$n}.jpg"
prop_checkBraceExpansionVars4 = verify checkBraceExpansionVars "echo {$i..100}"
checkBraceExpansionVars params t@(T_BraceExpansion id list) = mapM_ check list
where
check element =
when (any (`isInfixOf` toString element) ["$..", "..$"]) $
if isEvaled
then style id 2175 "Quote this invalid brace expansion since it should be passed literally to eval."
else warn id 2051 "Bash doesn't support variables in brace range expansions."
literalExt t =
case t of
T_DollarBraced {} -> return "$"
T_DollarExpansion {} -> return "$"
T_DollarArithmetic {} -> return "$"
otherwise -> return "-"
toString t = fromJust $ getLiteralStringExt literalExt t
isEvaled = fromMaybe False $
(`isUnqualifiedCommand` "eval") <$> getClosestCommand (parentMap params) t
checkBraceExpansionVars _ _ = return ()
prop_checkForDecimals1 = verify checkForDecimals "((3.14*c))"
prop_checkForDecimals2 = verify checkForDecimals "foo[1.2]=bar"
prop_checkForDecimals3 = verifyNot checkForDecimals "declare -A foo; foo[1.2]=bar"
checkForDecimals params t@(TA_Expansion id _) = potentially $ do
guard $ not (hasFloatingPoint params)
str <- getLiteralString t
first <- str !!! 0
guard $ isDigit first && '.' `elem` str
return $ err id 2079 "(( )) doesn't support decimals. Use bc or awk."
checkForDecimals _ _ = return ()
prop_checkDivBeforeMult = verify checkDivBeforeMult "echo $((c/n*100))"
prop_checkDivBeforeMult2 = verifyNot checkDivBeforeMult "echo $((c*100/n))"
prop_checkDivBeforeMult3 = verifyNot checkDivBeforeMult "echo $((c/10*10))"
checkDivBeforeMult params (TA_Binary _ "*" (TA_Binary id "/" _ x) y)
| not (hasFloatingPoint params) && x /= y =
info id 2017 "Increase precision by replacing a/b*c with a*c/b."
checkDivBeforeMult _ _ = return ()
prop_checkArithmeticDeref = verify checkArithmeticDeref "echo $((3+$foo))"
prop_checkArithmeticDeref2 = verify checkArithmeticDeref "cow=14; (( s+= $cow ))"
prop_checkArithmeticDeref3 = verifyNot checkArithmeticDeref "cow=1/40; (( s+= ${cow%%/*} ))"
prop_checkArithmeticDeref4 = verifyNot checkArithmeticDeref "(( ! $? ))"
prop_checkArithmeticDeref5 = verifyNot checkArithmeticDeref "(($1))"
prop_checkArithmeticDeref6 = verify checkArithmeticDeref "(( a[$i] ))"
prop_checkArithmeticDeref7 = verifyNot checkArithmeticDeref "(( 10#$n ))"
prop_checkArithmeticDeref8 = verifyNot checkArithmeticDeref "let i=$i+1"
prop_checkArithmeticDeref9 = verifyNot checkArithmeticDeref "(( a[foo] ))"
prop_checkArithmeticDeref10= verifyNot checkArithmeticDeref "(( a[\\$foo] ))"
prop_checkArithmeticDeref11= verifyNot checkArithmeticDeref "a[$foo]=wee"
prop_checkArithmeticDeref12= verify checkArithmeticDeref "for ((i=0; $i < 3; i)); do true; done"
prop_checkArithmeticDeref13= verifyNot checkArithmeticDeref "(( $$ ))"
checkArithmeticDeref params t@(TA_Expansion _ [b@(T_DollarBraced id _)]) =
unless (isException $ bracedString b) getWarning
where
isException [] = True
isException s = any (`elem` "/.:#%?*@$-") s || isDigit (head s)
getWarning = fromMaybe noWarning . msum . map warningFor $ parents params t
warningFor t =
case t of
T_Arithmetic {} -> return normalWarning
T_DollarArithmetic {} -> return normalWarning
T_ForArithmetic {} -> return normalWarning
TA_Index {} -> return indexWarning
T_SimpleCommand {} -> return noWarning
_ -> Nothing
normalWarning = style id 2004 "$/${} is unnecessary on arithmetic variables."
indexWarning = style id 2149 "Remove $/${} for numeric index, or escape it for string."
noWarning = return ()
checkArithmeticDeref _ _ = return ()
prop_checkArithmeticBadOctal1 = verify checkArithmeticBadOctal "(( 0192 ))"
prop_checkArithmeticBadOctal2 = verifyNot checkArithmeticBadOctal "(( 0x192 ))"
prop_checkArithmeticBadOctal3 = verifyNot checkArithmeticBadOctal "(( 1 ^ 0777 ))"
checkArithmeticBadOctal _ t@(TA_Expansion id _) = potentially $ do
str <- getLiteralString t
guard $ str `matches` octalRE
return $ err id 2080 "Numbers with leading 0 are considered octal."
where
octalRE = mkRegex "^0[0-7]*[8-9]"
checkArithmeticBadOctal _ _ = return ()
prop_checkComparisonAgainstGlob = verify checkComparisonAgainstGlob "[[ $cow == $bar ]]"
prop_checkComparisonAgainstGlob2 = verifyNot checkComparisonAgainstGlob "[[ $cow == \"$bar\" ]]"
prop_checkComparisonAgainstGlob3 = verify checkComparisonAgainstGlob "[ $cow = *foo* ]"
prop_checkComparisonAgainstGlob4 = verifyNot checkComparisonAgainstGlob "[ $cow = foo ]"
prop_checkComparisonAgainstGlob5 = verify checkComparisonAgainstGlob "[[ $cow != $bar ]]"
checkComparisonAgainstGlob _ (TC_Binary _ DoubleBracket op _ (T_NormalWord id [T_DollarBraced _ _]))
| op `elem` ["=", "==", "!="] =
warn id 2053 $ "Quote the rhs of " ++ op ++ " in [[ ]] to prevent glob matching."
checkComparisonAgainstGlob _ (TC_Binary _ SingleBracket op _ word)
| (op == "=" || op == "==") && isGlob word =
err (getId word) 2081 "[ .. ] can't match globs. Use [[ .. ]] or grep."
checkComparisonAgainstGlob _ _ = return ()
prop_checkCommarrays1 = verify checkCommarrays "a=(1, 2)"
prop_checkCommarrays2 = verify checkCommarrays "a+=(1,2,3)"
prop_checkCommarrays3 = verifyNot checkCommarrays "cow=(1 \"foo,bar\" 3)"
prop_checkCommarrays4 = verifyNot checkCommarrays "cow=('one,' 'two')"
prop_checkCommarrays5 = verify checkCommarrays "a=([a]=b, [c]=d)"
prop_checkCommarrays6 = verify checkCommarrays "a=([a]=b,[c]=d,[e]=f)"
checkCommarrays _ (T_Array id l) =
when (any (isCommaSeparated . literal) l) $
warn id 2054 "Use spaces, not commas, to separate array elements."
where
literal (T_IndexedElement _ _ l) = literal l
literal (T_NormalWord _ l) = concatMap literal l
literal (T_Literal _ str) = str
literal _ = "str"
isCommaSeparated str = "," `isSuffixOf` str || length (filter (== ',') str) > 1
checkCommarrays _ _ = return ()
prop_checkOrNeq1 = verify checkOrNeq "if [[ $lol -ne cow || $lol -ne foo ]]; then echo foo; fi"
prop_checkOrNeq2 = verify checkOrNeq "(( a!=lol || a!=foo ))"
prop_checkOrNeq3 = verify checkOrNeq "[ \"$a\" != lol || \"$a\" != foo ]"
prop_checkOrNeq4 = verifyNot checkOrNeq "[ a != $cow || b != $foo ]"
prop_checkOrNeq5 = verifyNot checkOrNeq "[[ $a != /home || $a != */public_html/* ]]"
checkOrNeq _ (TC_Or id typ op (TC_Binary _ _ op1 lhs1 rhs1 ) (TC_Binary _ _ op2 lhs2 rhs2))
| lhs1 == lhs2 && (op1 == op2 && (op1 == "-ne" || op1 == "!=")) && not (any isGlob [rhs1,rhs2]) =
warn id 2055 $ "You probably wanted " ++ (if typ == SingleBracket then "-a" else "&&") ++ " here."
checkOrNeq _ (TA_Binary id "||" (TA_Binary _ "!=" word1 _) (TA_Binary _ "!=" word2 _))
| word1 == word2 =
warn id 2056 "You probably wanted && here."
checkOrNeq _ _ = return ()
prop_checkValidCondOps1 = verify checkValidCondOps "[[ a -xz b ]]"
prop_checkValidCondOps2 = verify checkValidCondOps "[ -M a ]"
prop_checkValidCondOps2a= verifyNot checkValidCondOps "[ 3 \\> 2 ]"
prop_checkValidCondOps3 = verifyNot checkValidCondOps "[ 1 = 2 -a 3 -ge 4 ]"
prop_checkValidCondOps4 = verifyNot checkValidCondOps "[[ ! -v foo ]]"
checkValidCondOps _ (TC_Binary id _ s _ _)
| s `notElem` ["-nt", "-ot", "-ef", "==", "!=", "<=", ">=", "-eq", "-ne", "-lt", "-le", "-gt", "-ge", "=~", ">", "<", "=", "\\<", "\\>", "\\<=", "\\>="] =
warn id 2057 "Unknown binary operator."
checkValidCondOps _ (TC_Unary id _ s _)
| s `notElem` [ "!", "-a", "-b", "-c", "-d", "-e", "-f", "-g", "-h", "-L", "-k", "-p", "-r", "-s", "-S", "-t", "-u", "-w", "-x", "-O", "-G", "-N", "-z", "-n", "-o", "-v", "-R"] =
warn id 2058 "Unknown unary operator."
checkValidCondOps _ _ = return ()
prop_checkUuoeVar1 = verify checkUuoeVar "for f in $(echo $tmp); do echo lol; done"
prop_checkUuoeVar2 = verify checkUuoeVar "date +`echo \"$format\"`"
prop_checkUuoeVar3 = verifyNot checkUuoeVar "foo \"$(echo -e '\r')\""
prop_checkUuoeVar4 = verifyNot checkUuoeVar "echo $tmp"
prop_checkUuoeVar5 = verify checkUuoeVar "foo \"$(echo \"$(date) value:\" $value)\""
prop_checkUuoeVar6 = verifyNot checkUuoeVar "foo \"$(echo files: *.png)\""
prop_checkUuoeVar7 = verifyNot checkUuoeVar "foo $(echo $(bar))"
prop_checkUuoeVar8 = verifyNot checkUuoeVar "#!/bin/sh\nz=$(echo)"
prop_checkUuoeVar9 = verify checkUuoeVar "foo $(echo $(<file))"
checkUuoeVar _ p =
case p of
T_Backticked id [cmd] -> check id cmd
T_DollarExpansion id [cmd] -> check id cmd
_ -> return ()
where
couldBeOptimized f = case f of
T_Glob {} -> False
T_Extglob {} -> False
T_BraceExpansion {} -> False
T_NormalWord _ l -> all couldBeOptimized l
T_DoubleQuoted _ l -> all couldBeOptimized l
_ -> True
check id (T_Pipeline _ _ [T_Redirecting _ _ c]) = warnForEcho id c
check _ _ = return ()
isCovered first rest = null rest && tokenIsJustCommandOutput first
warnForEcho id = checkUnqualifiedCommand "echo" $ \_ vars ->
case vars of
(first:rest) ->
unless (isCovered first rest || "-" `isPrefixOf` onlyLiteralString first) $
when (all couldBeOptimized vars) $ style id 2116
"Useless echo? Instead of 'cmd $(echo foo)', just use 'cmd foo'."
otherwise -> return ()
prop_checkTimeParameters1 = verify checkTimeParameters "time -f lol sleep 10"
prop_checkTimeParameters2 = verifyNot checkTimeParameters "time sleep 10"
prop_checkTimeParameters3 = verifyNot checkTimeParameters "time -p foo"
checkTimeParameters _ = checkUnqualifiedCommand "time" f where
f cmd (x:_) = let s = concat $ oversimplify x in
when ("-" `isPrefixOf` s && s /= "-p") $
info (getId cmd) 2023 "The shell may override 'time' as seen in man time(1). Use 'command time ..' for that one."
f _ _ = return ()
prop_checkTimedCommand1 = verify checkTimedCommand "time -p foo | bar"
prop_checkTimedCommand2 = verify checkTimedCommand "time ( foo; bar; )"
prop_checkTimedCommand3 = verifyNot checkTimedCommand "time sleep 1"
checkTimedCommand _ = checkUnqualifiedCommand "time" f where
f c args@(_:_) = do
let cmd = last args
when (isPiped cmd) $
warn (getId c) 2176 "'time' is undefined for pipelines. time single stage or bash -c instead."
when (isSimple cmd == Just False) $
warn (getId cmd) 2177 "'time' is undefined for compound commands, time sh -c instead."
f _ _ = return ()
isPiped cmd =
case cmd of
T_Pipeline _ _ (_:_:_) -> True
_ -> False
getCommand cmd =
case cmd of
T_Pipeline _ _ ((T_Redirecting _ _ a):_) -> return a
_ -> fail ""
isSimple cmd = do
innerCommand <- getCommand cmd
case innerCommand of
T_SimpleCommand {} -> return True
_ -> return False
prop_checkTestRedirects1 = verify checkTestRedirects "test 3 > 1"
prop_checkTestRedirects2 = verifyNot checkTestRedirects "test 3 \\> 1"
prop_checkTestRedirects3 = verify checkTestRedirects "/usr/bin/test $var > $foo"
prop_checkTestRedirects4 = verifyNot checkTestRedirects "test 1 -eq 2 2> file"
checkTestRedirects _ (T_Redirecting id redirs cmd) | cmd `isCommand` "test" =
mapM_ check redirs
where
check t =
when (suspicious t) $
warn (getId t) 2065 "This is interpreted as a shell file redirection, not a comparison."
suspicious t =
case t of
T_FdRedirect _ fd (T_IoFile _ op _) -> fd /= "2" && isComparison op
otherwise -> False
isComparison t =
case t of
T_Greater _ -> True
T_Less _ -> True
otherwise -> False
checkTestRedirects _ _ = return ()
prop_checkSudoRedirect1 = verify checkSudoRedirect "sudo echo 3 > /proc/file"
prop_checkSudoRedirect2 = verify checkSudoRedirect "sudo cmd < input"
prop_checkSudoRedirect3 = verify checkSudoRedirect "sudo cmd >> file"
prop_checkSudoRedirect4 = verify checkSudoRedirect "sudo cmd &> file"
prop_checkSudoRedirect5 = verifyNot checkSudoRedirect "sudo cmd 2>&1"
prop_checkSudoRedirect6 = verifyNot checkSudoRedirect "sudo cmd 2> log"
prop_checkSudoRedirect7 = verifyNot checkSudoRedirect "sudo cmd > /dev/null 2>&1"
checkSudoRedirect _ (T_Redirecting _ redirs cmd) | cmd `isCommand` "sudo" =
mapM_ warnAbout redirs
where
warnAbout (T_FdRedirect _ s (T_IoFile id op file))
| (s == "" || s == "&") && not (special file) =
case op of
T_Less _ ->
info (getId op) 2024
"sudo doesn't affect redirects. Use sudo cat file | .."
T_Greater _ ->
warn (getId op) 2024
"sudo doesn't affect redirects. Use ..| sudo tee file"
T_DGREAT _ ->
warn (getId op) 2024
"sudo doesn't affect redirects. Use .. | sudo tee -a file"
_ -> return ()
warnAbout _ = return ()
special file = concat (oversimplify file) == "/dev/null"
checkSudoRedirect _ _ = return ()
prop_checkPS11 = verify checkPS1Assignments "PS1='\\033[1;35m\\$ '"
prop_checkPS11a= verify checkPS1Assignments "export PS1='\\033[1;35m\\$ '"
prop_checkPSf2 = verify checkPS1Assignments "PS1='\\h \\e[0m\\$ '"
prop_checkPS13 = verify checkPS1Assignments "PS1=$'\\x1b[c '"
prop_checkPS14 = verify checkPS1Assignments "PS1=$'\\e[3m; '"
prop_checkPS14a= verify checkPS1Assignments "export PS1=$'\\e[3m; '"
prop_checkPS15 = verifyNot checkPS1Assignments "PS1='\\[\\033[1;35m\\]\\$ '"
prop_checkPS16 = verifyNot checkPS1Assignments "PS1='\\[\\e1m\\e[1m\\]\\$ '"
prop_checkPS17 = verifyNot checkPS1Assignments "PS1='e033x1B'"
prop_checkPS18 = verifyNot checkPS1Assignments "PS1='\\[\\e\\]'"
checkPS1Assignments _ (T_Assignment _ _ "PS1" _ word) = warnFor word
where
warnFor word =
let contents = concat $ oversimplify word in
when (containsUnescaped contents) $
info (getId word) 2025 "Make sure all escape sequences are enclosed in \\[..\\] to prevent line wrapping issues"
containsUnescaped s =
let unenclosed = subRegex enclosedRegex s "" in
isJust $ matchRegex escapeRegex unenclosed
enclosedRegex = mkRegex "\\\\\\[.*\\\\\\]"
escapeRegex = mkRegex "\\\\x1[Bb]|\\\\e|\x1B|\\\\033"
checkPS1Assignments _ _ = return ()
prop_checkBackticks1 = verify checkBackticks "echo `foo`"
prop_checkBackticks2 = verifyNot checkBackticks "echo $(foo)"
prop_checkBackticks3 = verifyNot checkBackticks "echo `#inlined comment` foo"
checkBackticks _ (T_Backticked id list) | not (null list) =
style id 2006 "Use $(..) instead of legacy `..`."
checkBackticks _ _ = return ()
prop_checkIndirectExpansion1 = verify checkIndirectExpansion "${foo$n}"
prop_checkIndirectExpansion2 = verifyNot checkIndirectExpansion "${foo//$n/lol}"
prop_checkIndirectExpansion3 = verify checkIndirectExpansion "${$#}"
prop_checkIndirectExpansion4 = verify checkIndirectExpansion "${var${n}_$((i%2))}"
prop_checkIndirectExpansion5 = verifyNot checkIndirectExpansion "${bar}"
checkIndirectExpansion _ (T_DollarBraced i (T_NormalWord _ contents)) =
when (isIndirection contents) $
err i 2082 "To expand via indirection, use arrays, ${!name} or (for sh only) eval."
where
isIndirection vars =
let list = mapMaybe isIndirectionPart vars in
not (null list) && and list
isIndirectionPart t =
case t of T_DollarExpansion _ _ -> Just True
T_Backticked _ _ -> Just True
T_DollarBraced _ _ -> Just True
T_DollarArithmetic _ _ -> Just True
T_Literal _ s -> if all isVariableChar s
then Nothing
else Just False
_ -> Just False
checkIndirectExpansion _ _ = return ()
prop_checkInexplicablyUnquoted1 = verify checkInexplicablyUnquoted "echo 'var='value';'"
prop_checkInexplicablyUnquoted2 = verifyNot checkInexplicablyUnquoted "'foo'*"
prop_checkInexplicablyUnquoted3 = verifyNot checkInexplicablyUnquoted "wget --user-agent='something'"
prop_checkInexplicablyUnquoted4 = verify checkInexplicablyUnquoted "echo \"VALUES (\"id\")\""
prop_checkInexplicablyUnquoted5 = verifyNot checkInexplicablyUnquoted "\"$dir\"/\"$file\""
prop_checkInexplicablyUnquoted6 = verifyNot checkInexplicablyUnquoted "\"$dir\"some_stuff\"$file\""
checkInexplicablyUnquoted _ (T_NormalWord id tokens) = mapM_ check (tails tokens)
where
check (T_SingleQuoted _ _:T_Literal id str:_)
| all isAlphaNum str =
info id 2026 "This word is outside of quotes. Did you intend to 'nest '\"'single quotes'\"' instead'? "
check (T_DoubleQuoted _ a:trapped:T_DoubleQuoted _ b:_) =
case trapped of
T_DollarExpansion id _ -> warnAboutExpansion id
T_DollarBraced id _ -> warnAboutExpansion id
T_Literal id s ->
unless (quotesSingleThing a && quotesSingleThing b) $
warnAboutLiteral id
_ -> return ()
check _ = return ()
quotesSingleThing x = case x of
[T_DollarExpansion _ _] -> True
[T_DollarBraced _ _] -> True
[T_Backticked _ _] -> True
_ -> False
warnAboutExpansion id =
warn id 2027 "The surrounding quotes actually unquote this. Remove or escape them."
warnAboutLiteral id =
warn id 2140 "Word is on the form \"A\"B\"C\" (B indicated). Did you mean \"ABC\" or \"A\\\"B\\\"C\"?"
checkInexplicablyUnquoted _ _ = return ()
prop_checkTildeInQuotes1 = verify checkTildeInQuotes "var=\"~/out.txt\""
prop_checkTildeInQuotes2 = verify checkTildeInQuotes "foo > '~/dir'"
prop_checkTildeInQuotes4 = verifyNot checkTildeInQuotes "~/file"
prop_checkTildeInQuotes5 = verifyNot checkTildeInQuotes "echo '/~foo/cow'"
prop_checkTildeInQuotes6 = verifyNot checkTildeInQuotes "awk '$0 ~ /foo/'"
checkTildeInQuotes _ = check
where
verify id ('~':'/':_) = warn id 2088 "Tilde does not expand in quotes. Use $HOME."
verify _ _ = return ()
check (T_NormalWord _ (T_SingleQuoted id str:_)) =
verify id str
check (T_NormalWord _ (T_DoubleQuoted _ (T_Literal id str:_):_)) =
verify id str
check _ = return ()
prop_checkLonelyDotDash1 = verify checkLonelyDotDash "./ file"
prop_checkLonelyDotDash2 = verifyNot checkLonelyDotDash "./file"
checkLonelyDotDash _ t@(T_Redirecting id _ _)
| isUnqualifiedCommand t "./" =
err id 2083 "Don't add spaces after the slash in './file'."
checkLonelyDotDash _ _ = return ()
prop_checkSpuriousExec1 = verify checkSpuriousExec "exec foo; true"
prop_checkSpuriousExec2 = verify checkSpuriousExec "if a; then exec b; exec c; fi"
prop_checkSpuriousExec3 = verifyNot checkSpuriousExec "echo cow; exec foo"
prop_checkSpuriousExec4 = verifyNot checkSpuriousExec "if a; then exec b; fi"
prop_checkSpuriousExec5 = verifyNot checkSpuriousExec "exec > file; cmd"
prop_checkSpuriousExec6 = verify checkSpuriousExec "exec foo > file; cmd"
prop_checkSpuriousExec7 = verifyNot checkSpuriousExec "exec file; echo failed; exit 3"
checkSpuriousExec _ = doLists
where
doLists (T_Script _ _ cmds) = doList cmds
doLists (T_BraceGroup _ cmds) = doList cmds
doLists (T_WhileExpression _ _ cmds) = doList cmds
doLists (T_UntilExpression _ _ cmds) = doList cmds
doLists (T_ForIn _ _ _ cmds) = doList cmds
doLists (T_ForArithmetic _ _ _ _ cmds) = doList cmds
doLists (T_IfExpression _ thens elses) = do
mapM_ (\(_, l) -> doList l) thens
doList elses
doLists _ = return ()
stripCleanup = reverse . dropWhile cleanup . reverse
cleanup (T_Pipeline _ _ [cmd]) =
isCommandMatch cmd (`elem` ["echo", "exit"])
cleanup _ = False
doList = doList' . stripCleanup
doList' t@(current:following:_) = do
commentIfExec current
doList (tail t)
doList' _ = return ()
commentIfExec (T_Pipeline id _ list) =
mapM_ commentIfExec $ take 1 list
commentIfExec (T_Redirecting _ _ f@(
T_SimpleCommand id _ (cmd:arg:_))) =
when (f `isUnqualifiedCommand` "exec") $
warn id 2093
"Remove \"exec \" if script should continue after this command."
commentIfExec _ = return ()
prop_checkSpuriousExpansion1 = verify checkSpuriousExpansion "if $(true); then true; fi"
prop_checkSpuriousExpansion2 = verify checkSpuriousExpansion "while \"$(cmd)\"; do :; done"
prop_checkSpuriousExpansion3 = verifyNot checkSpuriousExpansion "$(cmd) --flag1 --flag2"
prop_checkSpuriousExpansion4 = verify checkSpuriousExpansion "$((i++))"
checkSpuriousExpansion _ (T_SimpleCommand _ _ [T_NormalWord _ [word]]) = check word
where
check word = case word of
T_DollarExpansion id _ ->
warn id 2091 "Remove surrounding $() to avoid executing output."
T_Backticked id _ ->
warn id 2092 "Remove backticks to avoid executing output."
T_DollarArithmetic id _ ->
err id 2084 "Remove '$' or use '_=$((expr))' to avoid executing output."
T_DoubleQuoted id [subword] -> check subword
_ -> return ()
checkSpuriousExpansion _ _ = return ()
prop_checkDollarBrackets1 = verify checkDollarBrackets "echo $[1+2]"
prop_checkDollarBrackets2 = verifyNot checkDollarBrackets "echo $((1+2))"
checkDollarBrackets _ (T_DollarBracket id _) =
style id 2007 "Use $((..)) instead of deprecated $[..]"
checkDollarBrackets _ _ = return ()
prop_checkSshHereDoc1 = verify checkSshHereDoc "ssh host << foo\necho $PATH\nfoo"
prop_checkSshHereDoc2 = verifyNot checkSshHereDoc "ssh host << 'foo'\necho $PATH\nfoo"
checkSshHereDoc _ (T_Redirecting _ redirs cmd)
| cmd `isCommand` "ssh" =
mapM_ checkHereDoc redirs
where
hasVariables = mkRegex "[`$]"
checkHereDoc (T_FdRedirect _ _ (T_HereDoc id _ Unquoted token tokens))
| not (all isConstant tokens) =
warn id 2087 $ "Quote '" ++ token ++ "' to make here document expansions happen on the server side rather than on the client."
checkHereDoc _ = return ()
checkSshHereDoc _ _ = return ()
prop_subshellAssignmentCheck = verifyTree subshellAssignmentCheck "cat foo | while read bar; do a=$bar; done; echo \"$a\""
prop_subshellAssignmentCheck2 = verifyNotTree subshellAssignmentCheck "while read bar; do a=$bar; done < file; echo \"$a\""
prop_subshellAssignmentCheck3 = verifyTree subshellAssignmentCheck "( A=foo; ); rm $A"
prop_subshellAssignmentCheck4 = verifyNotTree subshellAssignmentCheck "( A=foo; rm $A; )"
prop_subshellAssignmentCheck5 = verifyTree subshellAssignmentCheck "cat foo | while read cow; do true; done; echo $cow;"
prop_subshellAssignmentCheck6 = verifyTree subshellAssignmentCheck "( export lol=$(ls); ); echo $lol;"
prop_subshellAssignmentCheck6a= verifyTree subshellAssignmentCheck "( typeset -a lol=a; ); echo $lol;"
prop_subshellAssignmentCheck7 = verifyTree subshellAssignmentCheck "cmd | while read foo; do (( n++ )); done; echo \"$n lines\""
prop_subshellAssignmentCheck8 = verifyTree subshellAssignmentCheck "n=3 & echo $((n++))"
prop_subshellAssignmentCheck9 = verifyTree subshellAssignmentCheck "read n & n=foo$n"
prop_subshellAssignmentCheck10 = verifyTree subshellAssignmentCheck "(( n <<= 3 )) & (( n |= 4 )) &"
prop_subshellAssignmentCheck11 = verifyTree subshellAssignmentCheck "cat /etc/passwd | while read line; do let n=n+1; done\necho $n"
prop_subshellAssignmentCheck12 = verifyTree subshellAssignmentCheck "cat /etc/passwd | while read line; do let ++n; done\necho $n"
prop_subshellAssignmentCheck13 = verifyTree subshellAssignmentCheck "#!/bin/bash\necho foo | read bar; echo $bar"
prop_subshellAssignmentCheck14 = verifyNotTree subshellAssignmentCheck "#!/bin/ksh93\necho foo | read bar; echo $bar"
prop_subshellAssignmentCheck15 = verifyNotTree subshellAssignmentCheck "#!/bin/ksh\ncat foo | while read bar; do a=$bar; done\necho \"$a\""
prop_subshellAssignmentCheck16 = verifyNotTree subshellAssignmentCheck "(set -e); echo $@"
prop_subshellAssignmentCheck17 = verifyNotTree subshellAssignmentCheck "foo=${ { bar=$(baz); } 2>&1; }; echo $foo $bar"
prop_subshellAssignmentCheck18 = verifyTree subshellAssignmentCheck "( exec {n}>&2; ); echo $n"
subshellAssignmentCheck params t =
let flow = variableFlow params
check = findSubshelled flow [("oops",[])] Map.empty
in snd $ runWriter check
findSubshelled [] _ _ = return ()
findSubshelled (Assignment x@(_, _, str, _):rest) ((reason,scope):lol) deadVars =
findSubshelled rest ((reason, x:scope):lol) $ Map.insert str Alive deadVars
findSubshelled (Reference (_, readToken, str):rest) scopes deadVars = do
unless (shouldIgnore str) $ case Map.findWithDefault Alive str deadVars of
Alive -> return ()
Dead writeToken reason -> do
info (getId writeToken) 2030 $ "Modification of " ++ str ++ " is local (to subshell caused by "++ reason ++")."
info (getId readToken) 2031 $ str ++ " was modified in a subshell. That change might be lost."
findSubshelled rest scopes deadVars
where
shouldIgnore str =
str `elem` ["@", "*", "IFS"]
findSubshelled (StackScope (SubshellScope reason):rest) scopes deadVars =
findSubshelled rest ((reason,[]):scopes) deadVars
findSubshelled (StackScopeEnd:rest) ((reason, scope):oldScopes) deadVars =
findSubshelled rest oldScopes $
foldl (\m (_, token, var, _) ->
Map.insert var (Dead token reason) m) deadVars scope
doVariableFlowAnalysis ::
(Token -> Token -> String -> State t [v])
-> (Token -> Token -> String -> DataType -> State t [v])
-> t
-> [StackData]
-> [v]
doVariableFlowAnalysis readFunc writeFunc empty flow = evalState (
foldM (\list x -> do { l <- doFlow x; return $ l ++ list; }) [] flow
) empty
where
doFlow (Reference (base, token, name)) =
readFunc base token name
doFlow (Assignment (base, token, name, values)) =
writeFunc base token name values
doFlow _ = return []
prop_checkSpacefulness1 = verifyTree checkSpacefulness "a='cow moo'; echo $a"
prop_checkSpacefulness2 = verifyNotTree checkSpacefulness "a='cow moo'; [[ $a ]]"
prop_checkSpacefulness3 = verifyNotTree checkSpacefulness "a='cow*.mp3'; echo \"$a\""
prop_checkSpacefulness4 = verifyTree checkSpacefulness "for f in *.mp3; do echo $f; done"
prop_checkSpacefulness4a= verifyNotTree checkSpacefulness "foo=3; foo=$(echo $foo)"
prop_checkSpacefulness5 = verifyTree checkSpacefulness "a='*'; b=$a; c=lol${b//foo/bar}; echo $c"
prop_checkSpacefulness6 = verifyTree checkSpacefulness "a=foo$(lol); echo $a"
prop_checkSpacefulness7 = verifyTree checkSpacefulness "a=foo\\ bar; rm $a"
prop_checkSpacefulness8 = verifyNotTree checkSpacefulness "a=foo\\ bar; a=foo; rm $a"
prop_checkSpacefulness10= verifyTree checkSpacefulness "rm $1"
prop_checkSpacefulness11= verifyTree checkSpacefulness "rm ${10//foo/bar}"
prop_checkSpacefulness12= verifyNotTree checkSpacefulness "(( $1 + 3 ))"
prop_checkSpacefulness13= verifyNotTree checkSpacefulness "if [[ $2 -gt 14 ]]; then true; fi"
prop_checkSpacefulness14= verifyNotTree checkSpacefulness "foo=$3 env"
prop_checkSpacefulness15= verifyNotTree checkSpacefulness "local foo=$1"
prop_checkSpacefulness16= verifyNotTree checkSpacefulness "declare foo=$1"
prop_checkSpacefulness17= verifyTree checkSpacefulness "echo foo=$1"
prop_checkSpacefulness18= verifyNotTree checkSpacefulness "$1 --flags"
prop_checkSpacefulness19= verifyTree checkSpacefulness "echo $PWD"
prop_checkSpacefulness20= verifyNotTree checkSpacefulness "n+='foo bar'"
prop_checkSpacefulness21= verifyNotTree checkSpacefulness "select foo in $bar; do true; done"
prop_checkSpacefulness22= verifyNotTree checkSpacefulness "echo $\"$1\""
prop_checkSpacefulness23= verifyNotTree checkSpacefulness "a=(1); echo ${a[@]}"
prop_checkSpacefulness24= verifyTree checkSpacefulness "a='a b'; cat <<< $a"
prop_checkSpacefulness25= verifyTree checkSpacefulness "a='s/[0-9]//g'; sed $a"
prop_checkSpacefulness26= verifyTree checkSpacefulness "a='foo bar'; echo {1,2,$a}"
prop_checkSpacefulness27= verifyNotTree checkSpacefulness "echo ${a:+'foo'}"
prop_checkSpacefulness28= verifyNotTree checkSpacefulness "exec {n}>&1; echo $n"
prop_checkSpacefulness29= verifyNotTree checkSpacefulness "n=$(stuff); exec {n}>&-;"
prop_checkSpacefulness30= verifyTree checkSpacefulness "file='foo bar'; echo foo > $file;"
prop_checkSpacefulness31= verifyNotTree checkSpacefulness "echo \"`echo \\\"$1\\\"`\""
prop_checkSpacefulness32= verifyNotTree checkSpacefulness "var=$1; [ -v var ]"
checkSpacefulness params t =
doVariableFlowAnalysis readF writeF (Map.fromList defaults) (variableFlow params)
where
defaults = zip variablesWithoutSpaces (repeat False)
hasSpaces name = do
map <- get
return $ Map.findWithDefault True name map
setSpaces name bool =
modify $ Map.insert name bool
readF _ token name = do
spaced <- hasSpaces name
return [makeComment InfoC (getId token) 2086 warning |
isExpansion token && spaced
&& not (isArrayExpansion token)
&& not (isCounting token)
&& not (isQuoteFree parents token)
&& not (isQuotedAlternative token)
&& not (usedAsCommandName parents token)]
where
warning = "Double quote to prevent globbing and word splitting."
writeF _ _ name (DataString SourceExternal) = setSpaces name True >> return []
writeF _ _ name (DataString SourceInteger) = setSpaces name False >> return []
writeF _ _ name (DataString (SourceFrom vals)) = do
map <- get
setSpaces name
(isSpacefulWord (\x -> Map.findWithDefault True x map) vals)
return []
writeF _ _ _ _ = return []
parents = parentMap params
isExpansion t =
case t of
(T_DollarBraced _ _ ) -> True
_ -> False
isCounting (T_DollarBraced id token) =
case concat $ oversimplify token of
'#':_ -> True
_ -> False
isCounting _ = False
isQuotedAlternative t =
case t of
T_DollarBraced _ _ ->
":+" `isInfixOf` bracedString t
_ -> False
isSpacefulWord :: (String -> Bool) -> [Token] -> Bool
isSpacefulWord f = any (isSpaceful f)
isSpaceful :: (String -> Bool) -> Token -> Bool
isSpaceful spacefulF x =
case x of
T_DollarExpansion _ _ -> True
T_Backticked _ _ -> True
T_Glob _ _ -> True
T_Extglob {} -> True
T_Literal _ s -> s `containsAny` globspace
T_SingleQuoted _ s -> s `containsAny` globspace
T_DollarBraced _ _ -> spacefulF $ getBracedReference $ bracedString x
T_NormalWord _ w -> isSpacefulWord spacefulF w
T_DoubleQuoted _ w -> isSpacefulWord spacefulF w
_ -> False
where
globspace = "*?[] \t\n"
containsAny s = any (`elem` s)
prop_checkQuotesInLiterals1 = verifyTree checkQuotesInLiterals "param='--foo=\"bar\"'; app $param"
prop_checkQuotesInLiterals1a= verifyTree checkQuotesInLiterals "param=\"--foo='lolbar'\"; app $param"
prop_checkQuotesInLiterals2 = verifyNotTree checkQuotesInLiterals "param='--foo=\"bar\"'; app \"$param\""
prop_checkQuotesInLiterals3 =verifyNotTree checkQuotesInLiterals "param=('--foo='); app \"${param[@]}\""
prop_checkQuotesInLiterals4 = verifyNotTree checkQuotesInLiterals "param=\"don't bother with this one\"; app $param"
prop_checkQuotesInLiterals5 = verifyNotTree checkQuotesInLiterals "param=\"--foo='lolbar'\"; eval app $param"
prop_checkQuotesInLiterals6 = verifyTree checkQuotesInLiterals "param='my\\ file'; cmd=\"rm $param\"; $cmd"
prop_checkQuotesInLiterals6a= verifyNotTree checkQuotesInLiterals "param='my\\ file'; cmd=\"rm ${#param}\"; $cmd"
prop_checkQuotesInLiterals7 = verifyTree checkQuotesInLiterals "param='my\\ file'; rm $param"
prop_checkQuotesInLiterals8 = verifyTree checkQuotesInLiterals "param=\"/foo/'bar baz'/etc\"; rm $param"
prop_checkQuotesInLiterals9 = verifyNotTree checkQuotesInLiterals "param=\"/foo/'bar baz'/etc\"; rm ${#param}"
checkQuotesInLiterals params t =
doVariableFlowAnalysis readF writeF Map.empty (variableFlow params)
where
getQuotes name = liftM (Map.lookup name) get
setQuotes name ref = modify $ Map.insert name ref
deleteQuotes = modify . Map.delete
parents = parentMap params
quoteRegex = mkRegex "\"|([/= ]|^)'|'( |$)|\\\\ "
containsQuotes s = s `matches` quoteRegex
writeF _ _ name (DataString (SourceFrom values)) = do
quoteMap <- get
let quotedVars = msum $ map (forToken quoteMap) values
case quotedVars of
Nothing -> deleteQuotes name
Just x -> setQuotes name x
return []
writeF _ _ _ _ = return []
forToken map (T_DollarBraced id t) =
Map.lookup (concat . oversimplify $ t) map
forToken quoteMap (T_DoubleQuoted id tokens) =
msum $ map (forToken quoteMap) tokens
forToken quoteMap (T_NormalWord id tokens) =
msum $ map (forToken quoteMap) tokens
forToken _ t =
if containsQuotes (concat $ oversimplify t)
then return $ getId t
else Nothing
squashesQuotes t =
case t of
T_DollarBraced id _ -> "#" `isPrefixOf` bracedString t
otherwise -> False
readF _ expr name = do
assignment <- getQuotes name
return
(if isJust assignment
&& not (isParamTo parents "eval" expr)
&& not (isQuoteFree parents expr)
&& not (squashesQuotes expr)
then [
makeComment WarningC (fromJust assignment) 2089
"Quotes/backslashes will be treated literally. Use an array.",
makeComment WarningC (getId expr) 2090
"Quotes/backslashes in this variable will not be respected."
]
else [])
prop_checkFunctionsUsedExternally1 =
verifyTree checkFunctionsUsedExternally "foo() { :; }; sudo foo"
prop_checkFunctionsUsedExternally2 =
verifyTree checkFunctionsUsedExternally "alias f='a'; xargs -n 1 f"
prop_checkFunctionsUsedExternally3 =
verifyNotTree checkFunctionsUsedExternally "f() { :; }; echo f"
prop_checkFunctionsUsedExternally4 =
verifyNotTree checkFunctionsUsedExternally "foo() { :; }; sudo \"foo\""
checkFunctionsUsedExternally params t =
runNodeAnalysis checkCommand params t
where
invokingCmds = [
"chroot",
"find",
"screen",
"ssh",
"su",
"sudo",
"xargs"
]
checkCommand _ t@(T_SimpleCommand _ _ (cmd:args)) =
let name = fromMaybe "" $ getCommandBasename t in
when (name `elem` invokingCmds) $
mapM_ (checkArg name) args
checkCommand _ _ = return ()
analyse f t = execState (doAnalysis f t) []
functions = Map.fromList $ analyse findFunctions t
findFunctions (T_Function id _ _ name _) = modify ((name, id):)
findFunctions t@(T_SimpleCommand id _ (_:args))
| t `isUnqualifiedCommand` "alias" = mapM_ getAlias args
findFunctions _ = return ()
getAlias arg =
let string = concat $ oversimplify arg
in when ('=' `elem` string) $
modify ((takeWhile (/= '=') string, getId arg):)
checkArg cmd arg = potentially $ do
literalArg <- getUnquotedLiteral arg
definitionId <- Map.lookup literalArg functions
return $ do
warn (getId arg) 2033
"Shell functions can't be passed to external commands."
info definitionId 2032 $
"Use own script or sh -c '..' to run this from " ++ cmd ++ "."
prop_checkUnused0 = verifyNotTree checkUnusedAssignments "var=foo; echo $var"
prop_checkUnused1 = verifyTree checkUnusedAssignments "var=foo; echo $bar"
prop_checkUnused2 = verifyNotTree checkUnusedAssignments "var=foo; export var;"
prop_checkUnused3 = verifyTree checkUnusedAssignments "for f in *; do echo '$f'; done"
prop_checkUnused4 = verifyTree checkUnusedAssignments "local i=0"
prop_checkUnused5 = verifyNotTree checkUnusedAssignments "read lol; echo $lol"
prop_checkUnused6 = verifyNotTree checkUnusedAssignments "var=4; (( var++ ))"
prop_checkUnused7 = verifyNotTree checkUnusedAssignments "var=2; $((var))"
prop_checkUnused8 = verifyTree checkUnusedAssignments "var=2; var=3;"
prop_checkUnused9 = verifyNotTree checkUnusedAssignments "read ''"
prop_checkUnused10= verifyNotTree checkUnusedAssignments "read -p 'test: '"
prop_checkUnused11= verifyNotTree checkUnusedAssignments "bar=5; export foo[$bar]=3"
prop_checkUnused12= verifyNotTree checkUnusedAssignments "read foo; echo ${!foo}"
prop_checkUnused13= verifyNotTree checkUnusedAssignments "x=(1); (( x[0] ))"
prop_checkUnused14= verifyNotTree checkUnusedAssignments "x=(1); n=0; echo ${x[n]}"
prop_checkUnused15= verifyNotTree checkUnusedAssignments "x=(1); n=0; (( x[n] ))"
prop_checkUnused16= verifyNotTree checkUnusedAssignments "foo=5; declare -x foo"
prop_checkUnused17= verifyNotTree checkUnusedAssignments "read -i 'foo' -e -p 'Input: ' bar; $bar;"
prop_checkUnused18= verifyNotTree checkUnusedAssignments "a=1; arr=( [$a]=42 ); echo \"${arr[@]}\""
prop_checkUnused19= verifyNotTree checkUnusedAssignments "a=1; let b=a+1; echo $b"
prop_checkUnused20= verifyNotTree checkUnusedAssignments "a=1; PS1='$a'"
prop_checkUnused21= verifyNotTree checkUnusedAssignments "a=1; trap 'echo $a' INT"
prop_checkUnused22= verifyNotTree checkUnusedAssignments "a=1; [ -v a ]"
prop_checkUnused23= verifyNotTree checkUnusedAssignments "a=1; [ -R a ]"
prop_checkUnused24= verifyNotTree checkUnusedAssignments "mapfile -C a b; echo ${b[@]}"
prop_checkUnused25= verifyNotTree checkUnusedAssignments "readarray foo; echo ${foo[@]}"
prop_checkUnused26= verifyNotTree checkUnusedAssignments "declare -F foo"
prop_checkUnused27= verifyTree checkUnusedAssignments "var=3; [ var -eq 3 ]"
prop_checkUnused28= verifyNotTree checkUnusedAssignments "var=3; [[ var -eq 3 ]]"
prop_checkUnused29= verifyNotTree checkUnusedAssignments "var=(a b); declare -p var"
prop_checkUnused30= verifyTree checkUnusedAssignments "let a=1"
prop_checkUnused31= verifyTree checkUnusedAssignments "let 'a=1'"
prop_checkUnused32= verifyTree checkUnusedAssignments "let a=b=c; echo $a"
prop_checkUnused33= verifyNotTree checkUnusedAssignments "a=foo; [[ foo =~ ^{$a}$ ]]"
prop_checkUnused34= verifyNotTree checkUnusedAssignments "foo=1; (( t = foo )); echo $t"
prop_checkUnused35= verifyNotTree checkUnusedAssignments "a=foo; b=2; echo ${a:b}"
checkUnusedAssignments params t = execWriter (mapM_ warnFor unused)
where
flow = variableFlow params
references = foldl (flip ($)) defaultMap (map insertRef flow)
insertRef (Reference (base, token, name)) =
Map.insert (stripSuffix name) ()
insertRef _ = id
assignments = foldl (flip ($)) Map.empty (map insertAssignment flow)
insertAssignment (Assignment (_, token, name, _)) | isVariableName name =
Map.insert name token
insertAssignment _ = id
unused = Map.assocs $ Map.difference assignments references
warnFor (name, token) =
warn (getId token) 2034 $
name ++ " appears unused. Verify it or export it."
stripSuffix = takeWhile isVariableChar
defaultMap = Map.fromList $ zip internalVariables $ repeat ()
prop_checkUnassignedReferences1 = verifyTree checkUnassignedReferences "echo $foo"
prop_checkUnassignedReferences2 = verifyNotTree checkUnassignedReferences "foo=hello; echo $foo"
prop_checkUnassignedReferences3 = verifyTree checkUnassignedReferences "MY_VALUE=3; echo $MYVALUE"
prop_checkUnassignedReferences4 = verifyNotTree checkUnassignedReferences "RANDOM2=foo; echo $RANDOM"
prop_checkUnassignedReferences5 = verifyNotTree checkUnassignedReferences "declare -A foo=([bar]=baz); echo ${foo[bar]}"
prop_checkUnassignedReferences6 = verifyNotTree checkUnassignedReferences "foo=..; echo ${foo-bar}"
prop_checkUnassignedReferences7 = verifyNotTree checkUnassignedReferences "getopts ':h' foo; echo $foo"
prop_checkUnassignedReferences8 = verifyNotTree checkUnassignedReferences "let 'foo = 1'; echo $foo"
prop_checkUnassignedReferences9 = verifyNotTree checkUnassignedReferences "echo ${foo-bar}"
prop_checkUnassignedReferences10= verifyNotTree checkUnassignedReferences "echo ${foo:?}"
prop_checkUnassignedReferences11= verifyNotTree checkUnassignedReferences "declare -A foo; echo \"${foo[@]}\""
prop_checkUnassignedReferences12= verifyNotTree checkUnassignedReferences "typeset -a foo; echo \"${foo[@]}\""
prop_checkUnassignedReferences13= verifyNotTree checkUnassignedReferences "f() { local foo; echo $foo; }"
prop_checkUnassignedReferences14= verifyNotTree checkUnassignedReferences "foo=; echo $foo"
prop_checkUnassignedReferences15= verifyNotTree checkUnassignedReferences "f() { true; }; export -f f"
prop_checkUnassignedReferences16= verifyNotTree checkUnassignedReferences "declare -A foo=( [a b]=bar ); echo ${foo[a b]}"
prop_checkUnassignedReferences17= verifyNotTree checkUnassignedReferences "USERS=foo; echo $USER"
prop_checkUnassignedReferences18= verifyNotTree checkUnassignedReferences "FOOBAR=42; export FOOBAR="
prop_checkUnassignedReferences19= verifyNotTree checkUnassignedReferences "readonly foo=bar; echo $foo"
prop_checkUnassignedReferences20= verifyNotTree checkUnassignedReferences "printf -v foo bar; echo $foo"
prop_checkUnassignedReferences21= verifyTree checkUnassignedReferences "echo ${#foo}"
prop_checkUnassignedReferences22= verifyNotTree checkUnassignedReferences "echo ${!os*}"
prop_checkUnassignedReferences23= verifyTree checkUnassignedReferences "declare -a foo; foo[bar]=42;"
prop_checkUnassignedReferences24= verifyNotTree checkUnassignedReferences "declare -A foo; foo[bar]=42;"
prop_checkUnassignedReferences25= verifyNotTree checkUnassignedReferences "declare -A foo=(); foo[bar]=42;"
prop_checkUnassignedReferences26= verifyNotTree checkUnassignedReferences "a::b() { foo; }; readonly -f a::b"
prop_checkUnassignedReferences27= verifyNotTree checkUnassignedReferences ": ${foo:=bar}"
checkUnassignedReferences params t = warnings
where
(readMap, writeMap) = execState (mapM tally $ variableFlow params) (Map.empty, Map.empty)
defaultAssigned = Map.fromList $ map (\a -> (a, ())) $ filter (not . null) internalVariables
tally (Assignment (_, _, name, _)) =
modify (\(read, written) -> (read, Map.insert name () written))
tally (Reference (_, place, name)) =
modify (\(read, written) -> (Map.insertWith' (const id) name place read, written))
tally _ = return ()
unassigned = Map.toList $ Map.difference (Map.difference readMap writeMap) defaultAssigned
writtenVars = filter isVariableName $ Map.keys writeMap
getBestMatch var = do
(match, score) <- listToMaybe best
guard $ goodMatch var match score
return match
where
matches = map (\x -> (x, match var x)) writtenVars
best = sortBy (comparing snd) matches
goodMatch var match score =
let l = length match in
l > 3 && score <= 1
|| l > 7 && score <= 2
isLocal = any isLower
warningForGlobals var place = do
match <- getBestMatch var
return $ warn (getId place) 2153 $
"Possible misspelling: " ++ var ++ " may not be assigned, but " ++ match ++ " is."
warningForLocals var place =
return $ warn (getId place) 2154 $
var ++ " is referenced but not assigned" ++ optionalTip ++ "."
where
optionalTip =
if var `elem` commonCommands
then " (for output from commands, use \"$(" ++ var ++ " ..." ++ ")\" )"
else fromMaybe "" $ do
match <- getBestMatch var
return $ " (did you mean '" ++ match ++ "'?)"
warningFor var place = do
guard . not $ isInArray var place || isGuarded place
(if isLocal var then warningForLocals else warningForGlobals) var place
warnings = execWriter . sequence $ mapMaybe (uncurry warningFor) unassigned
isInArray var t = any isArray $ getPath (parentMap params) t
where
isArray (T_Array {}) = True
isArray b@(T_DollarBraced _ _) | var /= getBracedReference (bracedString b) = True
isArray _ = False
isGuarded (T_DollarBraced _ v) =
any (`isPrefixOf` rest) ["-", ":-", "?", ":?"]
where
name = concat $ oversimplify v
rest = dropWhile isVariableChar $ dropWhile (`elem` "#!") name
isGuarded _ = False
match var candidate =
if var /= candidate && map toLower var == map toLower candidate
then 1
else dist var candidate
prop_checkGlobsAsOptions1 = verify checkGlobsAsOptions "rm *.txt"
prop_checkGlobsAsOptions2 = verify checkGlobsAsOptions "ls ??.*"
prop_checkGlobsAsOptions3 = verifyNot checkGlobsAsOptions "rm -- *.txt"
checkGlobsAsOptions _ (T_SimpleCommand _ _ args) =
mapM_ check $ takeWhile (not . isEndOfArgs) args
where
check v@(T_NormalWord _ (T_Glob id s:_)) | s == "*" || s == "?" =
info id 2035 "Use ./*glob* or -- *glob* so names with dashes won't become options."
check _ = return ()
isEndOfArgs t =
case concat $ oversimplify t of
"--" -> True
":::" -> True
"::::" -> True
_ -> False
checkGlobsAsOptions _ _ = return ()
prop_checkWhileReadPitfalls1 = verify checkWhileReadPitfalls "while read foo; do ssh $foo uptime; done < file"
prop_checkWhileReadPitfalls2 = verifyNot checkWhileReadPitfalls "while read -u 3 foo; do ssh $foo uptime; done 3< file"
prop_checkWhileReadPitfalls3 = verifyNot checkWhileReadPitfalls "while true; do ssh host uptime; done"
prop_checkWhileReadPitfalls4 = verifyNot checkWhileReadPitfalls "while read foo; do ssh $foo hostname < /dev/null; done"
prop_checkWhileReadPitfalls5 = verifyNot checkWhileReadPitfalls "while read foo; do echo ls | ssh $foo; done"
prop_checkWhileReadPitfalls6 = verifyNot checkWhileReadPitfalls "while read foo <&3; do ssh $foo; done 3< foo"
prop_checkWhileReadPitfalls7 = verify checkWhileReadPitfalls "while read foo; do if true; then ssh $foo uptime; fi; done < file"
checkWhileReadPitfalls _ (T_WhileExpression id [command] contents)
| isStdinReadCommand command =
mapM_ checkMuncher contents
where
munchers = [ "ssh", "ffmpeg", "mplayer" ]
isStdinReadCommand (T_Pipeline _ _ [T_Redirecting id redirs cmd]) =
let plaintext = oversimplify cmd
in head (plaintext ++ [""]) == "read"
&& ("-u" `notElem` plaintext)
&& all (not . stdinRedirect) redirs
isStdinReadCommand _ = False
checkMuncher (T_Pipeline _ _ (T_Redirecting _ redirs cmd:_)) | not $ any stdinRedirect redirs =
case cmd of
(T_IfExpression _ thens elses) ->
mapM_ checkMuncher . concat $ map fst thens ++ map snd thens ++ [elses]
_ -> potentially $ do
name <- getCommandBasename cmd
guard $ name `elem` munchers
return $ do
info id 2095 $
name ++ " may swallow stdin, preventing this loop from working properly."
warn (getId cmd) 2095 $
"Add < /dev/null to prevent " ++ name ++ " from swallowing stdin."
checkMuncher _ = return ()
stdinRedirect (T_FdRedirect _ fd _)
| fd == "" || fd == "0" = True
stdinRedirect _ = False
checkWhileReadPitfalls _ _ = return ()
prop_checkPrefixAssign1 = verify checkPrefixAssignmentReference "var=foo echo $var"
prop_checkPrefixAssign2 = verifyNot checkPrefixAssignmentReference "var=$(echo $var) cmd"
checkPrefixAssignmentReference params t@(T_DollarBraced id value) =
check path
where
name = getBracedReference $ bracedString t
path = getPath (parentMap params) t
idPath = map getId path
check [] = return ()
check (t:rest) =
case t of
T_SimpleCommand _ vars (_:_) -> mapM_ checkVar vars
otherwise -> check rest
checkVar (T_Assignment aId mode aName [] value) |
aName == name && (aId `notElem` idPath) = do
warn aId 2097 "This assignment is only seen by the forked process."
warn id 2098 "This expansion will not see the mentioned assignment."
checkVar _ = return ()
checkPrefixAssignmentReference _ _ = return ()
prop_checkCharRangeGlob1 = verify checkCharRangeGlob "ls *[:digit:].jpg"
prop_checkCharRangeGlob2 = verifyNot checkCharRangeGlob "ls *[[:digit:]].jpg"
prop_checkCharRangeGlob3 = verify checkCharRangeGlob "ls [10-15]"
prop_checkCharRangeGlob4 = verifyNot checkCharRangeGlob "ls [a-zA-Z]"
prop_checkCharRangeGlob5 = verifyNot checkCharRangeGlob "tr -d [a-zA-Z]"
checkCharRangeGlob p t@(T_Glob id str) |
isCharClass str && not (isParamTo (parentMap p) "tr" t) =
if ":" `isPrefixOf` contents
&& ":" `isSuffixOf` contents
&& contents /= ":"
then warn id 2101 "Named class needs outer [], e.g. [[:digit:]]."
else
when ('[' `notElem` contents && hasDupes) $
info id 2102 "Ranges can only match single chars (mentioned due to duplicates)."
where
isCharClass str = "[" `isPrefixOf` str && "]" `isSuffixOf` str
contents = drop 1 . take (length str 1) $ str
hasDupes = any (>1) . map length . group . sort . filter (/= '-') $ contents
checkCharRangeGlob _ _ = return ()
prop_checkCdAndBack1 = verify checkCdAndBack "for f in *; do cd $f; git pull; cd ..; done"
prop_checkCdAndBack2 = verifyNot checkCdAndBack "for f in *; do cd $f || continue; git pull; cd ..; done"
prop_checkCdAndBack3 = verifyNot checkCdAndBack "while [[ $PWD != / ]]; do cd ..; done"
prop_checkCdAndBack4 = verify checkCdAndBack "cd $tmp; foo; cd -"
checkCdAndBack params = doLists
where
shell = shellType params
doLists (T_ForIn _ _ _ cmds) = doList cmds
doLists (T_ForArithmetic _ _ _ _ cmds) = doList cmds
doLists (T_WhileExpression _ _ cmds) = doList cmds
doLists (T_UntilExpression _ _ cmds) = doList cmds
doLists (T_Script _ _ cmds) = doList cmds
doLists (T_IfExpression _ thens elses) = do
mapM_ (\(_, l) -> doList l) thens
doList elses
doLists _ = return ()
isCdRevert t =
case oversimplify t of
["cd", p] -> p `elem` ["..", "-"]
_ -> False
getCmd (T_Annotation id _ x) = getCmd x
getCmd (T_Pipeline id _ [x]) = getCommandName x
getCmd _ = Nothing
doList list =
let cds = filter ((== Just "cd") . getCmd) list in
when (length cds >= 2 && isCdRevert (last cds)) $
info (getId $ last cds) 2103 message
message = "Use a ( subshell ) to avoid having to cd back."
prop_checkLoopKeywordScope1 = verify checkLoopKeywordScope "continue 2"
prop_checkLoopKeywordScope2 = verify checkLoopKeywordScope "for f; do ( break; ); done"
prop_checkLoopKeywordScope3 = verify checkLoopKeywordScope "if true; then continue; fi"
prop_checkLoopKeywordScope4 = verifyNot checkLoopKeywordScope "while true; do break; done"
prop_checkLoopKeywordScope5 = verify checkLoopKeywordScope "if true; then break; fi"
prop_checkLoopKeywordScope6 = verify checkLoopKeywordScope "while true; do true | { break; }; done"
prop_checkLoopKeywordScope7 = verifyNot checkLoopKeywordScope "#!/bin/ksh\nwhile true; do true | { break; }; done"
checkLoopKeywordScope params t |
name `elem` map Just ["continue", "break"] =
if not $ any isLoop path
then if any isFunction $ take 1 path
then err (getId t) 2104 $ "In functions, use return instead of " ++ fromJust name ++ "."
else err (getId t) 2105 $ fromJust name ++ " is only valid in loops."
else case map subshellType $ filter (not . isFunction) path of
Just str:_ -> warn (getId t) 2106 $
"This only exits the subshell caused by the " ++ str ++ "."
_ -> return ()
where
name = getCommandName t
path = let p = getPath (parentMap params) t in filter relevant p
subshellType t = case leadType (shellType params) (parentMap params) t of
NoneScope -> Nothing
SubshellScope str -> return str
relevant t = isLoop t || isFunction t || isJust (subshellType t)
checkLoopKeywordScope _ _ = return ()
prop_checkLocalScope1 = verify checkLocalScope "local foo=3"
prop_checkLocalScope2 = verifyNot checkLocalScope "f() { local foo=3; }"
checkLocalScope params t | t `isCommand` "local" && not (isInFunction t) =
err (getId t) 2168 "'local' is only valid in functions."
where
isInFunction t = any isFunction $ getPath (parentMap params) t
checkLocalScope _ _ = return ()
prop_checkFunctionDeclarations1 = verify checkFunctionDeclarations "#!/bin/ksh\nfunction foo() { command foo --lol \"$@\"; }"
prop_checkFunctionDeclarations2 = verify checkFunctionDeclarations "#!/bin/dash\nfunction foo { lol; }"
prop_checkFunctionDeclarations3 = verifyNot checkFunctionDeclarations "foo() { echo bar; }"
checkFunctionDeclarations params
(T_Function id (FunctionKeyword hasKeyword) (FunctionParentheses hasParens) _ _) =
case shellType params of
Bash -> return ()
Ksh ->
when (hasKeyword && hasParens) $
err id 2111 "ksh does not allow 'function' keyword and '()' at the same time."
Dash -> forSh
Sh -> forSh
where
forSh = do
when (hasKeyword && hasParens) $
warn id 2112 "'function' keyword is non-standard. Delete it."
when (hasKeyword && not hasParens) $
warn id 2113 "'function' keyword is non-standard. Use 'foo()' instead of 'function foo'."
checkFunctionDeclarations _ _ = return ()
prop_checkCatastrophicRm1 = verify checkCatastrophicRm "rm -r $1/$2"
prop_checkCatastrophicRm2 = verify checkCatastrophicRm "rm -r /home/$foo"
prop_checkCatastrophicRm3 = verifyNot checkCatastrophicRm "rm -r /home/${USER:?}/*"
prop_checkCatastrophicRm4 = verify checkCatastrophicRm "rm -fr /home/$(whoami)/*"
prop_checkCatastrophicRm5 = verifyNot checkCatastrophicRm "rm -r /home/${USER:-thing}/*"
prop_checkCatastrophicRm6 = verify checkCatastrophicRm "rm --recursive /etc/*$config*"
prop_checkCatastrophicRm8 = verify checkCatastrophicRm "rm -rf /home"
prop_checkCatastrophicRm9 = verifyNot checkCatastrophicRm "rm -rf -- /home"
prop_checkCatastrophicRm10= verifyNot checkCatastrophicRm "rm -r \"${DIR}\"/{.gitignore,.gitattributes,ci}"
prop_checkCatastrophicRm11= verify checkCatastrophicRm "rm -r /{bin,sbin}/$exec"
prop_checkCatastrophicRm12= verify checkCatastrophicRm "rm -r /{{usr,},{bin,sbin}}/$exec"
prop_checkCatastrophicRm13= verifyNot checkCatastrophicRm "rm -r /{{a,b},{c,d}}/$exec"
prop_checkCatastrophicRmA = verify checkCatastrophicRm "rm -rf /usr /lib/nvidia-current/xorg/xorg"
prop_checkCatastrophicRmB = verify checkCatastrophicRm "rm -rf \"$STEAMROOT/\"*"
checkCatastrophicRm params t@(T_SimpleCommand id _ tokens) | t `isCommand` "rm" =
when (any isRecursiveFlag simpleArgs) $
mapM_ (mapM_ checkWord . braceExpand) tokens
where
simpleArgs = oversimplify t
checkWord token =
case getLiteralString token of
Just str ->
when (notElem "--" simpleArgs && (fixPath str `elem` importantPaths)) $
warn (getId token) 2114 "Warning: deletes a system directory. Use 'rm --' to disable this message."
Nothing ->
checkWord' token
checkWord' token = fromMaybe (return ()) $ do
filename <- getPotentialPath token
let path = fixPath filename
return . when (path `elem` importantPaths) $
warn (getId token) 2115 $ "Use \"${var:?}\" to ensure this never expands to " ++ path ++ " ."
fixPath filename =
let normalized = skipRepeating '/' . skipRepeating '*' $ filename in
if normalized == "/" then normalized else stripTrailing '/' normalized
getPotentialPath = getLiteralStringExt f
where
f (T_Glob _ str) = return str
f (T_DollarBraced _ word) =
let var = onlyLiteralString word in
if any (flip isInfixOf var) [":?", ":-", ":="]
then Nothing
else return ""
f _ = return ""
isRecursiveFlag "--recursive" = True
isRecursiveFlag ('-':'-':_) = False
isRecursiveFlag ('-':str) = 'r' `elem` str || 'R' `elem` str
isRecursiveFlag _ = False
stripTrailing c = reverse . dropWhile (== c) . reverse
skipRepeating c (a:b:rest) | a == b && b == c = skipRepeating c (b:rest)
skipRepeating c (a:r) = a:skipRepeating c r
skipRepeating _ [] = []
paths = [
"", "/bin", "/etc", "/home", "/mnt", "/usr", "/usr/share", "/usr/local",
"/var", "/lib"
]
importantPaths = filter (not . null) $
["", "/", "/*", "/*/*"] >>= (\x -> map (++x) paths)
checkCatastrophicRm _ _ = return ()
prop_checkStderrPipe1 = verify checkStderrPipe "#!/bin/ksh\nfoo |& bar"
prop_checkStderrPipe2 = verifyNot checkStderrPipe "#!/bin/bash\nfoo |& bar"
checkStderrPipe params =
case shellType params of
Ksh -> match
_ -> const $ return ()
where
match (T_Pipe id "|&") =
err id 2118 "Ksh does not support |&. Use 2>&1 |."
match _ = return ()
prop_checkUnpassedInFunctions1 = verifyTree checkUnpassedInFunctions "foo() { echo $1; }; foo"
prop_checkUnpassedInFunctions2 = verifyNotTree checkUnpassedInFunctions "foo() { echo $1; };"
prop_checkUnpassedInFunctions3 = verifyNotTree checkUnpassedInFunctions "foo() { echo $lol; }; foo"
prop_checkUnpassedInFunctions4 = verifyNotTree checkUnpassedInFunctions "foo() { echo $0; }; foo"
prop_checkUnpassedInFunctions5 = verifyNotTree checkUnpassedInFunctions "foo() { echo $1; }; foo 'lol'; foo"
prop_checkUnpassedInFunctions6 = verifyNotTree checkUnpassedInFunctions "foo() { set -- *; echo $1; }; foo"
prop_checkUnpassedInFunctions7 = verifyTree checkUnpassedInFunctions "foo() { echo $1; }; foo; foo;"
prop_checkUnpassedInFunctions8 = verifyNotTree checkUnpassedInFunctions "foo() { echo $((1)); }; foo;"
prop_checkUnpassedInFunctions9 = verifyNotTree checkUnpassedInFunctions "foo() { echo $(($b)); }; foo;"
prop_checkUnpassedInFunctions10= verifyNotTree checkUnpassedInFunctions "foo() { echo $!; }; foo;"
prop_checkUnpassedInFunctions11= verifyNotTree checkUnpassedInFunctions "foo() { bar() { echo $1; }; bar baz; }; foo;"
checkUnpassedInFunctions params root =
execWriter $ mapM_ warnForGroup referenceGroups
where
functionMap :: Map.Map String Token
functionMap = Map.fromList $
map (\t@(T_Function _ _ _ name _) -> (name,t)) functions
functions = execWriter $ doAnalysis (tell . maybeToList . findFunction) root
findFunction t@(T_Function id _ _ name body) =
let flow = getVariableFlow (shellType params) (parentMap params) body
in
if any (isPositionalReference t) flow && not (any isPositionalAssignment flow)
then return t
else Nothing
findFunction _ = Nothing
isPositionalAssignment x =
case x of
Assignment (_, _, str, _) -> isPositional str
_ -> False
isPositionalReference function x =
case x of
Reference (_, t, str) -> isPositional str && t `isDirectChildOf` function
_ -> False
isDirectChildOf child parent = fromMaybe False $ do
function <- find (\x -> case x of T_Function {} -> True; _ -> False) $ getPath (parentMap params) child
return $ getId parent == getId function
referenceList :: [(String, Bool, Token)]
referenceList = execWriter $
doAnalysis (fromMaybe (return ()) . checkCommand) root
checkCommand :: Token -> Maybe (Writer [(String, Bool, Token)] ())
checkCommand t@(T_SimpleCommand _ _ (cmd:args)) = do
str <- getLiteralString cmd
unless (Map.member str functionMap) $ fail "irrelevant"
return $ tell [(str, null args, t)]
checkCommand _ = Nothing
isPositional str = str == "*" || str == "@"
|| (all isDigit str && str /= "0")
isArgumentless (_, b, _) = b
referenceGroups = Map.elems $ foldr updateWith Map.empty referenceList
updateWith x@(name, _, _) = Map.insertWith (++) name [x]
warnForGroup group =
when (all isArgumentless group) $ do
mapM_ suggestParams group
warnForDeclaration group
suggestParams (name, _, thing) =
info (getId thing) 2119 $
"Use " ++ name ++ " \"$@\" if function's $1 should mean script's $1."
warnForDeclaration ((name, _, _):_) =
warn (getId . fromJust $ Map.lookup name functionMap) 2120 $
name ++ " references arguments, but none are ever passed."
prop_checkOverridingPath1 = verify checkOverridingPath "PATH=\"$var/$foo\""
prop_checkOverridingPath2 = verify checkOverridingPath "PATH=\"mydir\""
prop_checkOverridingPath3 = verify checkOverridingPath "PATH=/cow/foo"
prop_checkOverridingPath4 = verifyNot checkOverridingPath "PATH=/cow/foo/bin"
prop_checkOverridingPath5 = verifyNot checkOverridingPath "PATH='/bin:/sbin'"
prop_checkOverridingPath6 = verifyNot checkOverridingPath "PATH=\"$var/$foo\" cmd"
prop_checkOverridingPath7 = verifyNot checkOverridingPath "PATH=$OLDPATH"
prop_checkOverridingPath8 = verifyNot checkOverridingPath "PATH=$PATH:/stuff"
checkOverridingPath _ (T_SimpleCommand _ vars []) =
mapM_ checkVar vars
where
checkVar (T_Assignment id Assign "PATH" [] word) =
let string = concat $ oversimplify word
in unless (any (`isInfixOf` string) ["/bin", "/sbin" ]) $ do
when ('/' `elem` string && ':' `notElem` string) $ notify id
when (isLiteral word && ':' `notElem` string && '/' `notElem` string) $ notify id
checkVar _ = return ()
notify id = warn id 2123 "PATH is the shell search path. Use another name."
checkOverridingPath _ _ = return ()
prop_checkTildeInPath1 = verify checkTildeInPath "PATH=\"$PATH:~/bin\""
prop_checkTildeInPath2 = verify checkTildeInPath "PATH='~foo/bin'"
prop_checkTildeInPath3 = verifyNot checkTildeInPath "PATH=~/bin"
checkTildeInPath _ (T_SimpleCommand _ vars _) =
mapM_ checkVar vars
where
checkVar (T_Assignment id Assign "PATH" [] (T_NormalWord _ parts)) =
when (any (\x -> isQuoted x && hasTilde x) parts) $
warn id 2147 "Literal tilde in PATH works poorly across programs."
checkVar _ = return ()
hasTilde t = fromMaybe False (liftM2 elem (return '~') (getLiteralStringExt (const $ return "") t))
isQuoted (T_DoubleQuoted {}) = True
isQuoted (T_SingleQuoted {}) = True
isQuoted _ = False
checkTildeInPath _ _ = return ()
prop_checkUnsupported3 = verify checkUnsupported "#!/bin/sh\ncase foo in bar) baz ;& esac"
prop_checkUnsupported4 = verify checkUnsupported "#!/bin/ksh\ncase foo in bar) baz ;;& esac"
prop_checkUnsupported5 = verify checkUnsupported "#!/bin/bash\necho \"${ ls; }\""
checkUnsupported params t =
when (not (null support) && (shellType params `notElem` support)) $
report name
where
(name, support) = shellSupport t
report s = err (getId t) 2127 $
"To use " ++ s ++ ", specify #!/usr/bin/env " ++
(map toLower . intercalate " or " . map show $ support)
shellSupport t =
case t of
T_CaseExpression _ _ list -> forCase (map (\(a,_,_) -> a) list)
T_DollarBraceCommandExpansion {} -> ("${ ..; } command expansion", [Ksh])
otherwise -> ("", [])
where
forCase seps | CaseContinue `elem` seps = ("cases with ;;&", [Bash])
forCase seps | CaseFallThrough `elem` seps = ("cases with ;&", [Bash, Ksh])
forCase _ = ("", [])
groupWith f = groupBy ((==) `on` f)
prop_checkMultipleAppends1 = verify checkMultipleAppends "foo >> file; bar >> file; baz >> file;"
prop_checkMultipleAppends2 = verify checkMultipleAppends "foo >> file; bar | grep f >> file; baz >> file;"
prop_checkMultipleAppends3 = verifyNot checkMultipleAppends "foo < file; bar < file; baz < file;"
checkMultipleAppends params t =
mapM_ checkList $ getCommandSequences t
where
checkList list =
mapM_ checkGroup (groupWith (liftM fst) $ map getTarget list)
checkGroup (f:_:_:_) | isJust f =
style (snd $ fromJust f) 2129
"Consider using { cmd1; cmd2; } >> file instead of individual redirects."
checkGroup _ = return ()
getTarget (T_Annotation _ _ t) = getTarget t
getTarget (T_Pipeline _ _ args@(_:_)) = getTarget (last args)
getTarget (T_Redirecting id list _) = do
file <- mapMaybe getAppend list !!! 0
return (file, id)
getTarget _ = Nothing
getAppend (T_FdRedirect _ _ (T_IoFile _ (T_DGREAT {}) f)) = return f
getAppend _ = Nothing
prop_checkSuspiciousIFS1 = verify checkSuspiciousIFS "IFS=\"\\n\""
prop_checkSuspiciousIFS2 = verifyNot checkSuspiciousIFS "IFS=$'\\t'"
checkSuspiciousIFS params (T_Assignment id Assign "IFS" [] value) =
potentially $ do
str <- getLiteralString value
return $ check str
where
n = if shellType params == Sh then "'<literal linefeed here>'" else "$'\\n'"
t = if shellType params == Sh then "\"$(printf '\\t')\"" else "$'\\t'"
check value =
case value of
"\\n" -> suggest n
"/n" -> suggest n
"\\t" -> suggest t
"/t" -> suggest t
_ -> return ()
suggest r = warn id 2141 $ "Did you mean IFS=" ++ r ++ " ?"
checkSuspiciousIFS _ _ = return ()
prop_checkGrepQ1= verify checkShouldUseGrepQ "[[ $(foo | grep bar) ]]"
prop_checkGrepQ2= verify checkShouldUseGrepQ "[ -z $(fgrep lol) ]"
prop_checkGrepQ3= verify checkShouldUseGrepQ "[ -n \"$(foo | zgrep lol)\" ]"
prop_checkGrepQ4= verifyNot checkShouldUseGrepQ "[ -z $(grep bar | cmd) ]"
prop_checkGrepQ5= verifyNot checkShouldUseGrepQ "rm $(ls | grep file)"
prop_checkGrepQ6= verifyNot checkShouldUseGrepQ "[[ -n $(pgrep foo) ]]"
checkShouldUseGrepQ params t =
potentially $ case t of
TC_Noary id _ token -> check id True token
TC_Unary id _ "-n" token -> check id True token
TC_Unary id _ "-z" token -> check id False token
_ -> fail "not check"
where
check id bool token = do
name <- getFinalGrep token
let op = if bool then "-n" else "-z"
let flip = if bool then "" else "! "
return . style id 2143 $
"Use " ++ flip ++ name ++ " -q instead of " ++
"comparing output with [ " ++ op ++ " .. ]."
getFinalGrep t = do
cmds <- getPipeline t
guard . not . null $ cmds
name <- getCommandBasename $ last cmds
guard . isGrep $ name
return name
getPipeline t =
case t of
T_NormalWord _ [x] -> getPipeline x
T_DoubleQuoted _ [x] -> getPipeline x
T_DollarExpansion _ [x] -> getPipeline x
T_Pipeline _ _ cmds -> return cmds
_ -> fail "unknown"
isGrep = (`elem` ["grep", "egrep", "fgrep", "zgrep"])
prop_checkTestGlobs1 = verify checkTestGlobs "[ -e *.mp3 ]"
prop_checkTestGlobs2 = verifyNot checkTestGlobs "[[ $a == *b* ]]"
checkTestGlobs params (TC_Unary _ _ op token) | isGlob token =
err (getId token) 2144 $
op ++ " doesn't work with globs. Use a for loop."
checkTestGlobs _ _ = return ()
prop_checkMaskedReturns1 = verify checkMaskedReturns "f() { local a=$(false); }"
prop_checkMaskedReturns2 = verify checkMaskedReturns "declare a=$(false)"
prop_checkMaskedReturns3 = verify checkMaskedReturns "declare a=\"`false`\""
prop_checkMaskedReturns4 = verifyNot checkMaskedReturns "declare a; a=$(false)"
prop_checkMaskedReturns5 = verifyNot checkMaskedReturns "f() { local -r a=$(false); }"
checkMaskedReturns _ t@(T_SimpleCommand id _ (cmd:rest)) = potentially $ do
name <- getCommandName t
guard $ name `elem` ["declare", "export"]
|| name == "local" && "r" `notElem` map snd (getAllFlags t)
return $ mapM_ checkArgs rest
where
checkArgs (T_Assignment id _ _ _ word) | any hasReturn $ getWordParts word =
warn id 2155 "Declare and assign separately to avoid masking return values."
checkArgs _ = return ()
hasReturn t = case t of
T_Backticked {} -> True
T_DollarExpansion {} -> True
_ -> False
checkMaskedReturns _ _ = return ()
prop_checkReadWithoutR1 = verify checkReadWithoutR "read -a foo"
prop_checkReadWithoutR2 = verifyNot checkReadWithoutR "read -ar foo"
checkReadWithoutR _ t@(T_SimpleCommand {}) | t `isUnqualifiedCommand` "read" =
unless ("r" `elem` map snd (getAllFlags t)) $
info (getId t) 2162 "read without -r will mangle backslashes."
checkReadWithoutR _ _ = return ()
prop_checkUncheckedCd1 = verifyTree checkUncheckedCd "cd ~/src; rm -r foo"
prop_checkUncheckedCd2 = verifyNotTree checkUncheckedCd "cd ~/src || exit; rm -r foo"
prop_checkUncheckedCd3 = verifyNotTree checkUncheckedCd "set -e; cd ~/src; rm -r foo"
prop_checkUncheckedCd4 = verifyNotTree checkUncheckedCd "if cd foo; then rm foo; fi"
prop_checkUncheckedCd5 = verifyTree checkUncheckedCd "if true; then cd foo; fi"
prop_checkUncheckedCd6 = verifyNotTree checkUncheckedCd "cd .."
prop_checkUncheckedCd7 = verifyNotTree checkUncheckedCd "#!/bin/bash -e\ncd foo\nrm bar"
prop_checkUncheckedCd8 = verifyNotTree checkUncheckedCd "set -o errexit; cd foo; rm bar"
checkUncheckedCd params root =
if hasSetE then [] else execWriter $ doAnalysis checkElement root
where
checkElement t@(T_SimpleCommand {}) =
when(t `isUnqualifiedCommand` "cd"
&& not (isCdDotDot t)
&& not (isCondition $ getPath (parentMap params) t)) $
warn (getId t) 2164 "Use cd ... || exit in case cd fails."
checkElement _ = return ()
isCdDotDot t = oversimplify t == ["cd", ".."]
hasSetE = isNothing $ doAnalysis (guard . not . isSetE) root
isSetE t =
case t of
T_Script _ str _ -> str `matches` re
T_SimpleCommand {} ->
t `isUnqualifiedCommand` "set" &&
("errexit" `elem` oversimplify t || "e" `elem` map snd (getAllFlags t))
_ -> False
re = mkRegex "[[:space:]]-[^-]*e"
prop_checkLoopVariableReassignment1 = verify checkLoopVariableReassignment "for i in *; do for i in *.bar; do true; done; done"
prop_checkLoopVariableReassignment2 = verify checkLoopVariableReassignment "for i in *; do for((i=0; i<3; i++)); do true; done; done"
prop_checkLoopVariableReassignment3 = verifyNot checkLoopVariableReassignment "for i in *; do for j in *.bar; do true; done; done"
checkLoopVariableReassignment params token =
potentially $ case token of
T_ForIn {} -> check
T_ForArithmetic {} -> check
_ -> Nothing
where
check = do
str <- loopVariable token
next <- listToMaybe $ filter (\x -> loopVariable x == Just str) path
return $ do
warn (getId token) 2165 "This nested loop overrides the index variable of its parent."
warn (getId next) 2167 "This parent loop has its index variable overridden."
path = drop 1 $ getPath (parentMap params) token
loopVariable :: Token -> Maybe String
loopVariable t =
case t of
T_ForIn _ s _ _ -> return s
T_ForArithmetic _
(TA_Sequence _
[TA_Assignment _ "="
(TA_Expansion _ [T_Literal _ var]) _])
_ _ _ -> return var
_ -> fail "not loop"
prop_checkTrailingBracket1 = verify checkTrailingBracket "if -z n ]]; then true; fi "
prop_checkTrailingBracket2 = verifyNot checkTrailingBracket "if [[ -z n ]]; then true; fi "
prop_checkTrailingBracket3 = verify checkTrailingBracket "a || b ] && thing"
prop_checkTrailingBracket4 = verifyNot checkTrailingBracket "run [ foo ]"
prop_checkTrailingBracket5 = verifyNot checkTrailingBracket "run bar ']'"
checkTrailingBracket _ token =
case token of
T_SimpleCommand _ _ tokens@(_:_) -> check (last tokens) token
otherwise -> return ()
where
check t command =
case t of
T_NormalWord id [T_Literal _ str] -> potentially $ do
guard $ str `elem` [ "]]", "]" ]
let opposite = invert str
parameters = oversimplify command
guard $ opposite `notElem` parameters
return $ warn id 2171 $
"Found trailing " ++ str ++ " outside test. Missing " ++ opposite ++ "?"
otherwise -> return ()
invert s =
case s of
"]]" -> "[["
"]" -> "["
x -> x
prop_checkMultiDimensionalArrays1 = verify checkMultiDimensionalArrays "foo[a][b]=3"
prop_checkMultiDimensionalArrays2 = verifyNot checkMultiDimensionalArrays "foo[a]=3"
prop_checkMultiDimensionalArrays3 = verify checkMultiDimensionalArrays "foo=( [a][b]=c )"
prop_checkMultiDimensionalArrays4 = verifyNot checkMultiDimensionalArrays "foo=( [a]=c )"
prop_checkMultiDimensionalArrays5 = verify checkMultiDimensionalArrays "echo ${foo[bar][baz]}"
prop_checkMultiDimensionalArrays6 = verifyNot checkMultiDimensionalArrays "echo ${foo[bar]}"
checkMultiDimensionalArrays _ token =
case token of
T_Assignment _ _ name (first:second:_) _ -> about second
T_IndexedElement _ (first:second:_) _ -> about second
T_DollarBraced {} ->
when (isMultiDim token) $ about token
_ -> return ()
where
about t = warn (getId t) 2180 "Bash does not support multidimensional arrays. Use 1D or associative arrays."
re = mkRegex "^\\[.*\\]\\[.*\\]"
isMultiDim t = getBracedModifier (bracedString t) `matches` re
prop_checkReturnAgainstZero1 = verify checkReturnAgainstZero "[ $? -eq 0 ]"
prop_checkReturnAgainstZero2 = verify checkReturnAgainstZero "[[ \"$?\" -gt 0 ]]"
prop_checkReturnAgainstZero3 = verify checkReturnAgainstZero "[[ 0 -ne $? ]]"
prop_checkReturnAgainstZero4 = verifyNot checkReturnAgainstZero "[[ $? -eq 4 ]]"
prop_checkReturnAgainstZero5 = verify checkReturnAgainstZero "[[ 0 -eq $? ]]"
prop_checkReturnAgainstZero6 = verifyNot checkReturnAgainstZero "[[ $R -eq 0 ]]"
prop_checkReturnAgainstZero7 = verify checkReturnAgainstZero "(( $? == 0 ))"
prop_checkReturnAgainstZero8 = verify checkReturnAgainstZero "(( $? ))"
prop_checkReturnAgainstZero9 = verify checkReturnAgainstZero "(( ! $? ))"
checkReturnAgainstZero _ token =
case token of
TC_Binary id _ _ lhs rhs -> check lhs rhs
TA_Binary id _ lhs rhs -> check lhs rhs
TA_Unary id _ exp ->
when (isExitCode exp) $ message (getId exp)
TA_Sequence _ [exp] ->
when (isExitCode exp) $ message (getId exp)
otherwise -> return ()
where
check lhs rhs =
if isZero rhs && isExitCode lhs
then message (getId lhs)
else when (isZero lhs && isExitCode rhs) $ message (getId rhs)
isZero t = getLiteralString t == Just "0"
isExitCode t =
case getWordParts t of
[exp@(T_DollarBraced {})] -> bracedString exp == "?"
otherwise -> False
message id = style id 2181 "Check exit code directly with e.g. 'if mycmd;', not indirectly with $?."
return []
runTests = $( [| $(forAllProperties) (quickCheckWithResult (stdArgs { maxSuccess = 1 }) ) |])