Get rid of potentially

This already exists as sequence_.
This commit is contained in:
Joseph C. Sible 2020-02-09 20:10:09 -05:00
parent 4bfe6496d9
commit 7e6a556ef1
4 changed files with 32 additions and 41 deletions

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@ -1209,7 +1209,7 @@ prop_checkLiteralBreakingTest6 = verify checkLiteralBreakingTest "[ -z $(true)z
prop_checkLiteralBreakingTest7 = verifyNot checkLiteralBreakingTest "[ -z $(true) ]" prop_checkLiteralBreakingTest7 = verifyNot checkLiteralBreakingTest "[ -z $(true) ]"
prop_checkLiteralBreakingTest8 = verifyNot checkLiteralBreakingTest "[ $(true)$(true) ]" prop_checkLiteralBreakingTest8 = verifyNot checkLiteralBreakingTest "[ $(true)$(true) ]"
prop_checkLiteralBreakingTest10 = verify checkLiteralBreakingTest "[ -z foo ]" prop_checkLiteralBreakingTest10 = verify checkLiteralBreakingTest "[ -z foo ]"
checkLiteralBreakingTest _ t = potentially $ checkLiteralBreakingTest _ t = sequence_ $
case t of case t of
(TC_Nullary _ _ w@(T_NormalWord _ l)) -> do (TC_Nullary _ _ w@(T_NormalWord _ l)) -> do
guard . not $ isConstant w -- Covered by SC2078 guard . not $ isConstant w -- Covered by SC2078
@ -1257,7 +1257,7 @@ checkConstantNullary _ _ = return ()
prop_checkForDecimals1 = verify checkForDecimals "((3.14*c))" prop_checkForDecimals1 = verify checkForDecimals "((3.14*c))"
prop_checkForDecimals2 = verify checkForDecimals "foo[1.2]=bar" prop_checkForDecimals2 = verify checkForDecimals "foo[1.2]=bar"
prop_checkForDecimals3 = verifyNot checkForDecimals "declare -A foo; foo[1.2]=bar" prop_checkForDecimals3 = verifyNot checkForDecimals "declare -A foo; foo[1.2]=bar"
checkForDecimals params t@(TA_Expansion id _) = potentially $ do checkForDecimals params t@(TA_Expansion id _) = sequence_ $ do
guard $ not (hasFloatingPoint params) guard $ not (hasFloatingPoint params)
str <- getLiteralString t str <- getLiteralString t
first <- str !!! 0 first <- str !!! 0
@ -1310,7 +1310,7 @@ checkArithmeticDeref _ _ = return ()
prop_checkArithmeticBadOctal1 = verify checkArithmeticBadOctal "(( 0192 ))" prop_checkArithmeticBadOctal1 = verify checkArithmeticBadOctal "(( 0192 ))"
prop_checkArithmeticBadOctal2 = verifyNot checkArithmeticBadOctal "(( 0x192 ))" prop_checkArithmeticBadOctal2 = verifyNot checkArithmeticBadOctal "(( 0x192 ))"
prop_checkArithmeticBadOctal3 = verifyNot checkArithmeticBadOctal "(( 1 ^ 0777 ))" prop_checkArithmeticBadOctal3 = verifyNot checkArithmeticBadOctal "(( 1 ^ 0777 ))"
checkArithmeticBadOctal _ t@(TA_Expansion id _) = potentially $ do checkArithmeticBadOctal _ t@(TA_Expansion id _) = sequence_ $ do
str <- getLiteralString t str <- getLiteralString t
guard $ str `matches` octalRE guard $ str `matches` octalRE
return $ err id 2080 "Numbers with leading 0 are considered octal." return $ err id 2080 "Numbers with leading 0 are considered octal."
@ -1392,7 +1392,7 @@ checkOrNeq _ (TA_Binary id "||" (TA_Binary _ "!=" word1 _) (TA_Binary _ "!=" wor
warn id 2056 "You probably wanted && here, otherwise it's always true." warn id 2056 "You probably wanted && here, otherwise it's always true."
-- For command level "or": [ x != y ] || [ x != z ] -- For command level "or": [ x != y ] || [ x != z ]
checkOrNeq _ (T_OrIf id lhs rhs) = potentially $ do checkOrNeq _ (T_OrIf id lhs rhs) = sequence_ $ do
(lhs1, op1, rhs1) <- getExpr lhs (lhs1, op1, rhs1) <- getExpr lhs
(lhs2, op2, rhs2) <- getExpr rhs (lhs2, op2, rhs2) <- getExpr rhs
guard $ op1 == op2 && op1 `elem` ["-ne", "!="] guard $ op1 == op2 && op1 `elem` ["-ne", "!="]
@ -1407,7 +1407,7 @@ checkOrNeq _ (T_OrIf id lhs rhs) = potentially $ do
T_Redirecting _ _ c -> getExpr c T_Redirecting _ _ c -> getExpr c
T_Condition _ _ c -> getExpr c T_Condition _ _ c -> getExpr c
TC_Binary _ _ op lhs rhs -> return (lhs, op, rhs) TC_Binary _ _ op lhs rhs -> return (lhs, op, rhs)
_ -> fail "" _ -> Nothing
checkOrNeq _ _ = return () checkOrNeq _ _ = return ()
@ -2068,7 +2068,7 @@ checkFunctionsUsedExternally params t =
in when ('=' `elem` string) $ in when ('=' `elem` string) $
modify ((takeWhile (/= '=') string, getId arg):) modify ((takeWhile (/= '=') string, getId arg):)
checkArg cmd (_, arg) = potentially $ do checkArg cmd (_, arg) = sequence_ $ do
literalArg <- getUnquotedLiteral arg -- only consider unquoted literals literalArg <- getUnquotedLiteral arg -- only consider unquoted literals
definitionId <- Map.lookup literalArg functions definitionId <- Map.lookup literalArg functions
return $ do return $ do
@ -2312,7 +2312,7 @@ checkWhileReadPitfalls _ (T_WhileExpression id [command] contents)
(T_IfExpression _ thens elses) -> (T_IfExpression _ thens elses) ->
mapM_ checkMuncher . concat $ map fst thens ++ map snd thens ++ [elses] mapM_ checkMuncher . concat $ map fst thens ++ map snd thens ++ [elses]
_ -> potentially $ do _ -> sequence_ $ do
name <- getCommandBasename cmd name <- getCommandBasename cmd
guard $ name `elem` munchers guard $ name `elem` munchers
@ -2410,7 +2410,7 @@ checkCdAndBack params t =
else findCdPair (b:rest) else findCdPair (b:rest)
_ -> Nothing _ -> Nothing
doList list = potentially $ do doList list = sequence_ $ do
cd <- findCdPair $ mapMaybe getCandidate list cd <- findCdPair $ mapMaybe getCandidate list
return $ info cd 2103 "Use a ( subshell ) to avoid having to cd back." return $ info cd 2103 "Use a ( subshell ) to avoid having to cd back."
@ -2673,7 +2673,7 @@ prop_checkGrepQ4= verifyNot checkShouldUseGrepQ "[ -z $(grep bar | cmd) ]"
prop_checkGrepQ5= verifyNot checkShouldUseGrepQ "rm $(ls | grep file)" prop_checkGrepQ5= verifyNot checkShouldUseGrepQ "rm $(ls | grep file)"
prop_checkGrepQ6= verifyNot checkShouldUseGrepQ "[[ -n $(pgrep foo) ]]" prop_checkGrepQ6= verifyNot checkShouldUseGrepQ "[[ -n $(pgrep foo) ]]"
checkShouldUseGrepQ params t = checkShouldUseGrepQ params t =
potentially $ case t of sequence_ $ case t of
TC_Nullary id _ token -> check id True token TC_Nullary id _ token -> check id True token
TC_Unary id _ "-n" token -> check id True token TC_Unary id _ "-n" token -> check id True token
TC_Unary id _ "-z" token -> check id False token TC_Unary id _ "-z" token -> check id False token
@ -2807,7 +2807,7 @@ prop_checkMaskedReturns2 = verify checkMaskedReturns "declare a=$(false)"
prop_checkMaskedReturns3 = verify checkMaskedReturns "declare a=\"`false`\"" prop_checkMaskedReturns3 = verify checkMaskedReturns "declare a=\"`false`\""
prop_checkMaskedReturns4 = verifyNot checkMaskedReturns "declare a; a=$(false)" prop_checkMaskedReturns4 = verifyNot checkMaskedReturns "declare a; a=$(false)"
prop_checkMaskedReturns5 = verifyNot checkMaskedReturns "f() { local -r a=$(false); }" prop_checkMaskedReturns5 = verifyNot checkMaskedReturns "f() { local -r a=$(false); }"
checkMaskedReturns _ t@(T_SimpleCommand id _ (cmd:rest)) = potentially $ do checkMaskedReturns _ t@(T_SimpleCommand id _ (cmd:rest)) = sequence_ $ do
name <- getCommandName t name <- getCommandName t
guard $ name `elem` ["declare", "export"] guard $ name `elem` ["declare", "export"]
|| name == "local" && "r" `notElem` map snd (getAllFlags t) || name == "local" && "r" `notElem` map snd (getAllFlags t)
@ -2900,7 +2900,7 @@ prop_checkLoopVariableReassignment1 = verify checkLoopVariableReassignment "for
prop_checkLoopVariableReassignment2 = verify checkLoopVariableReassignment "for i in *; do for((i=0; i<3; i++)); 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" prop_checkLoopVariableReassignment3 = verifyNot checkLoopVariableReassignment "for i in *; do for j in *.bar; do true; done; done"
checkLoopVariableReassignment params token = checkLoopVariableReassignment params token =
potentially $ case token of sequence_ $ case token of
T_ForIn {} -> check T_ForIn {} -> check
T_ForArithmetic {} -> check T_ForArithmetic {} -> check
_ -> Nothing _ -> Nothing
@ -2988,12 +2988,12 @@ prop_checkRedirectedNowhere7 = verifyNot checkRedirectedNowhere "var=$(< file)"
prop_checkRedirectedNowhere8 = verifyNot checkRedirectedNowhere "var=`< file`" prop_checkRedirectedNowhere8 = verifyNot checkRedirectedNowhere "var=`< file`"
checkRedirectedNowhere params token = checkRedirectedNowhere params token =
case token of case token of
T_Pipeline _ _ [single] -> potentially $ do T_Pipeline _ _ [single] -> sequence_ $ do
redir <- getDanglingRedirect single redir <- getDanglingRedirect single
guard . not $ isInExpansion token guard . not $ isInExpansion token
return $ warn (getId redir) 2188 "This redirection doesn't have a command. Move to its command (or use 'true' as no-op)." return $ warn (getId redir) 2188 "This redirection doesn't have a command. Move to its command (or use 'true' as no-op)."
T_Pipeline _ _ list -> forM_ list $ \x -> potentially $ do T_Pipeline _ _ list -> forM_ list $ \x -> sequence_ $ do
redir <- getDanglingRedirect x redir <- getDanglingRedirect x
return $ err (getId redir) 2189 "You can't have | between this redirection and the command it should apply to." return $ err (getId redir) 2189 "You can't have | between this redirection and the command it should apply to."
@ -3080,7 +3080,7 @@ checkUnmatchableCases params t =
if isConstant word if isConstant word
then warn (getId word) 2194 then warn (getId word) 2194
"This word is constant. Did you forget the $ on a variable?" "This word is constant. Did you forget the $ on a variable?"
else potentially $ do else sequence_ $ do
pg <- wordToPseudoGlob word pg <- wordToPseudoGlob word
return $ mapM_ (check pg) allpatterns return $ mapM_ (check pg) allpatterns
@ -3095,7 +3095,7 @@ checkUnmatchableCases params t =
fst3 (x,_,_) = x fst3 (x,_,_) = x
snd3 (_,x,_) = x snd3 (_,x,_) = x
tp = tokenPositions params tp = tokenPositions params
check target candidate = potentially $ do check target candidate = sequence_ $ do
candidateGlob <- wordToPseudoGlob candidate candidateGlob <- wordToPseudoGlob candidate
guard . not $ pseudoGlobsCanOverlap target candidateGlob guard . not $ pseudoGlobsCanOverlap target candidateGlob
return $ warn (getId candidate) 2195 return $ warn (getId candidate) 2195
@ -3189,7 +3189,7 @@ prop_checkRedirectionToNumber2 = verify checkRedirectionToNumber "foo 1>2"
prop_checkRedirectionToNumber3 = verifyNot checkRedirectionToNumber "echo foo > '2'" prop_checkRedirectionToNumber3 = verifyNot checkRedirectionToNumber "echo foo > '2'"
prop_checkRedirectionToNumber4 = verifyNot checkRedirectionToNumber "foo 1>&2" prop_checkRedirectionToNumber4 = verifyNot checkRedirectionToNumber "foo 1>&2"
checkRedirectionToNumber _ t = case t of checkRedirectionToNumber _ t = case t of
T_IoFile id _ word -> potentially $ do T_IoFile id _ word -> sequence_ $ do
file <- getUnquotedLiteral word file <- getUnquotedLiteral word
guard $ all isDigit file guard $ all isDigit file
return $ warn id 2210 "This is a file redirection. Was it supposed to be a comparison or fd operation?" return $ warn id 2210 "This is a file redirection. Was it supposed to be a comparison or fd operation?"
@ -3238,7 +3238,7 @@ checkPipeToNowhere _ t =
T_Redirecting _ redirects cmd -> when (any redirectsStdin redirects) $ checkRedir cmd T_Redirecting _ redirects cmd -> when (any redirectsStdin redirects) $ checkRedir cmd
_ -> return () _ -> return ()
where where
checkPipe redir = potentially $ do checkPipe redir = sequence_ $ do
cmd <- getCommand redir cmd <- getCommand redir
name <- getCommandBasename cmd name <- getCommandBasename cmd
guard $ name `elem` nonReadingCommands guard $ name `elem` nonReadingCommands
@ -3251,7 +3251,7 @@ checkPipeToNowhere _ t =
return $ warn (getId cmd) 2216 $ return $ warn (getId cmd) 2216 $
"Piping to '" ++ name ++ "', a command that doesn't read stdin. " ++ suggestion "Piping to '" ++ name ++ "', a command that doesn't read stdin. " ++ suggestion
checkRedir cmd = potentially $ do checkRedir cmd = sequence_ $ do
name <- getCommandBasename cmd name <- getCommandBasename cmd
guard $ name `elem` nonReadingCommands guard $ name `elem` nonReadingCommands
guard . not $ hasAdditionalConsumers cmd guard . not $ hasAdditionalConsumers cmd
@ -3299,7 +3299,7 @@ checkUseBeforeDefinition _ t =
mapM_ (checkUsage m) $ concatMap recursiveSequences cmds mapM_ (checkUsage m) $ concatMap recursiveSequences cmds
_ -> return () _ -> return ()
checkUsage map cmd = potentially $ do checkUsage map cmd = sequence_ $ do
name <- getCommandName cmd name <- getCommandName cmd
def <- Map.lookup name map def <- Map.lookup name map
return $ return $

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@ -870,15 +870,6 @@ getBracedModifier s = fromMaybe "" . listToMaybe $ do
-- Useful generic functions. -- Useful generic functions.
-- Run an action in a Maybe (or do nothing).
-- Example:
-- potentially $ do
-- s <- getLiteralString cmd
-- guard $ s `elem` ["--recursive", "-r"]
-- return $ warn .. "Something something recursive"
potentially :: Monad m => Maybe (m ()) -> m ()
potentially = fromMaybe (return ())
-- Get element 0 or a default. Like `head` but safe. -- Get element 0 or a default. Like `head` but safe.
headOrDefault _ (a:_) = a headOrDefault _ (a:_) = a
headOrDefault def _ = def headOrDefault def _ = def

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@ -270,7 +270,7 @@ checkGrepRe = CommandCheck (Basename "grep") check where
let string = concat $ oversimplify re let string = concat $ oversimplify re
if isConfusedGlobRegex string then if isConfusedGlobRegex string then
warn (getId re) 2063 "Grep uses regex, but this looks like a glob." warn (getId re) 2063 "Grep uses regex, but this looks like a glob."
else potentially $ do else sequence_ $ do
char <- getSuspiciousRegexWildcard string char <- getSuspiciousRegexWildcard string
return $ info (getId re) 2022 $ return $ info (getId re) 2022 $
"Note that unlike globs, " ++ [char] ++ "* here matches '" ++ [char, char, char] ++ "' but not '" ++ wordStartingWith char ++ "'." "Note that unlike globs, " ++ [char] ++ "* here matches '" ++ [char, char, char] ++ "' but not '" ++ wordStartingWith char ++ "'."
@ -461,7 +461,7 @@ prop_checkMkdirDashPM20 = verifyNot checkMkdirDashPM "mkdir -p -m 0755 .././bin"
prop_checkMkdirDashPM21 = verifyNot checkMkdirDashPM "mkdir -p -m 0755 ../../bin" prop_checkMkdirDashPM21 = verifyNot checkMkdirDashPM "mkdir -p -m 0755 ../../bin"
checkMkdirDashPM = CommandCheck (Basename "mkdir") check checkMkdirDashPM = CommandCheck (Basename "mkdir") check
where where
check t = potentially $ do check t = sequence_ $ do
let flags = getAllFlags t let flags = getAllFlags t
dashP <- find ((\f -> f == "p" || f == "parents") . snd) flags dashP <- find ((\f -> f == "p" || f == "parents") . snd) flags
dashM <- find ((\f -> f == "m" || f == "mode") . snd) flags dashM <- find ((\f -> f == "m" || f == "mode") . snd) flags
@ -487,7 +487,7 @@ checkNonportableSignals = CommandCheck (Exactly "trap") (f . arguments)
first:rest -> unless (isFlag first) $ mapM_ check rest first:rest -> unless (isFlag first) $ mapM_ check rest
_ -> return () _ -> return ()
check param = potentially $ do check param = sequence_ $ do
str <- getLiteralString param str <- getLiteralString param
let id = getId param let id = getId param
return $ sequence_ $ mapMaybe (\f -> f id str) [ return $ sequence_ $ mapMaybe (\f -> f id str) [
@ -687,7 +687,7 @@ prop_checkExportedExpansions3 = verifyNot checkExportedExpansions "export foo"
prop_checkExportedExpansions4 = verifyNot checkExportedExpansions "export ${foo?}" prop_checkExportedExpansions4 = verifyNot checkExportedExpansions "export ${foo?}"
checkExportedExpansions = CommandCheck (Exactly "export") (mapM_ check . arguments) checkExportedExpansions = CommandCheck (Exactly "export") (mapM_ check . arguments)
where where
check t = potentially $ do check t = sequence_ $ do
var <- getSingleUnmodifiedVariable t var <- getSingleUnmodifiedVariable t
let name = bracedString var let name = bracedString var
return . warn (getId t) 2163 $ return . warn (getId t) 2163 $
@ -709,7 +709,7 @@ checkReadExpansions = CommandCheck (Exactly "read") check
return [y | (x,y) <- opts, null x || x == "a"] return [y | (x,y) <- opts, null x || x == "a"]
check cmd = mapM_ warning $ getVars cmd check cmd = mapM_ warning $ getVars cmd
warning t = potentially $ do warning t = sequence_ $ do
var <- getSingleUnmodifiedVariable t var <- getSingleUnmodifiedVariable t
let name = bracedString var let name = bracedString var
guard $ isVariableName name -- e.g. not $1 guard $ isVariableName name -- e.g. not $1
@ -859,7 +859,7 @@ checkWhileGetoptsCase = CommandCheck (Exactly "getopts") f
f :: Token -> Analysis f :: Token -> Analysis
f t@(T_SimpleCommand _ _ (cmd:arg1:_)) = do f t@(T_SimpleCommand _ _ (cmd:arg1:_)) = do
path <- getPathM t path <- getPathM t
potentially $ do sequence_ $ do
options <- getLiteralString arg1 options <- getLiteralString arg1
(T_WhileExpression _ _ body) <- findFirst whileLoop path (T_WhileExpression _ _ body) <- findFirst whileLoop path
caseCmd <- mapMaybe findCase body !!! 0 caseCmd <- mapMaybe findCase body !!! 0
@ -886,7 +886,7 @@ checkWhileGetoptsCase = CommandCheck (Exactly "getopts") f
warnUnhandled optId caseId str = warnUnhandled optId caseId str =
warn caseId 2213 $ "getopts specified -" ++ str ++ ", but it's not handled by this 'case'." warn caseId 2213 $ "getopts specified -" ++ str ++ ", but it's not handled by this 'case'."
warnRedundant (key, expr) = potentially $ do warnRedundant (key, expr) = sequence_ $ do
str <- key str <- key
guard $ str `notElem` ["*", ":", "?"] guard $ str `notElem` ["*", ":", "?"]
return $ warn (getId expr) 2214 "This case is not specified by getopts." return $ warn (getId expr) 2214 "This case is not specified by getopts."
@ -1081,7 +1081,7 @@ prop_checkSudoArgs6 = verifyNot checkSudoArgs "sudo -n -u export ls"
prop_checkSudoArgs7 = verifyNot checkSudoArgs "sudo docker export foo" prop_checkSudoArgs7 = verifyNot checkSudoArgs "sudo docker export foo"
checkSudoArgs = CommandCheck (Basename "sudo") f checkSudoArgs = CommandCheck (Basename "sudo") f
where where
f t = potentially $ do f t = sequence_ $ do
opts <- parseOpts t opts <- parseOpts t
let nonFlags = [x | ("",x) <- opts] let nonFlags = [x | ("",x) <- opts]
commandArg <- nonFlags !!! 0 commandArg <- nonFlags !!! 0
@ -1109,7 +1109,7 @@ prop_checkChmodDashr3 = verifyNot checkChmodDashr "chmod a-r dir"
checkChmodDashr = CommandCheck (Basename "chmod") f checkChmodDashr = CommandCheck (Basename "chmod") f
where where
f t = mapM_ check $ arguments t f t = mapM_ check $ arguments t
check t = potentially $ do check t = sequence_ $ do
flag <- getLiteralString t flag <- getLiteralString t
guard $ flag == "-r" guard $ flag == "-r"
return $ warn (getId t) 2253 "Use -R to recurse, or explicitly a-r to remove read permissions." return $ warn (getId t) 2253 "Use -R to recurse, or explicitly a-r to remove read permissions."

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@ -73,7 +73,7 @@ prop_checkForDecimals2 = verify checkForDecimals "foo[1.2]=bar"
prop_checkForDecimals3 = verifyNot checkForDecimals "declare -A foo; foo[1.2]=bar" prop_checkForDecimals3 = verifyNot checkForDecimals "declare -A foo; foo[1.2]=bar"
checkForDecimals = ForShell [Sh, Dash, Bash] f checkForDecimals = ForShell [Sh, Dash, Bash] f
where where
f t@(TA_Expansion id _) = potentially $ do f t@(TA_Expansion id _) = sequence_ $ do
str <- getLiteralString t str <- getLiteralString t
first <- str !!! 0 first <- str !!! 0
guard $ isDigit first && '.' `elem` str guard $ isDigit first && '.' `elem` str
@ -337,7 +337,7 @@ checkBashisms = ForShell [Sh, Dash] $ \t -> do
in do in do
when (name `elem` unsupportedCommands) $ when (name `elem` unsupportedCommands) $
warnMsg id $ "'" ++ name ++ "' is" warnMsg id $ "'" ++ name ++ "' is"
potentially $ do sequence_ $ do
allowed' <- Map.lookup name allowedFlags allowed' <- Map.lookup name allowedFlags
allowed <- allowed' allowed <- allowed'
(word, flag) <- find (word, flag) <- find
@ -347,7 +347,7 @@ checkBashisms = ForShell [Sh, Dash] $ \t -> do
when (name == "source") $ warnMsg id "'source' in place of '.' is" when (name == "source") $ warnMsg id "'source' in place of '.' is"
when (name == "trap") $ when (name == "trap") $
let let
check token = potentially $ do check token = sequence_ $ do
str <- getLiteralString token str <- getLiteralString token
let upper = map toUpper str let upper = map toUpper str
return $ do return $ do
@ -362,7 +362,7 @@ checkBashisms = ForShell [Sh, Dash] $ \t -> do
in in
mapM_ check (drop 1 rest) mapM_ check (drop 1 rest)
when (name == "printf") $ potentially $ do when (name == "printf") $ sequence_ $ do
format <- rest !!! 0 -- flags are covered by allowedFlags format <- rest !!! 0 -- flags are covered by allowedFlags
let literal = onlyLiteralString format let literal = onlyLiteralString format
guard $ "%q" `isInfixOf` literal guard $ "%q" `isInfixOf` literal