ShellCheck-0.10.0: src/ShellCheck/AnalyzerLib.hs
{-
Copyright 2012-2022 Vidar Holen
This file is part of ShellCheck.
https://www.shellcheck.net
ShellCheck is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.
ShellCheck is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program. If not, see <https://www.gnu.org/licenses/>.
-}
{-# LANGUAGE FlexibleContexts #-}
{-# LANGUAGE TemplateHaskell #-}
module ShellCheck.AnalyzerLib where
import ShellCheck.AST
import ShellCheck.ASTLib
import qualified ShellCheck.CFGAnalysis as CF
import ShellCheck.Data
import ShellCheck.Interface
import ShellCheck.Parser
import ShellCheck.Prelude
import ShellCheck.Regex
import Control.Arrow (first)
import Control.DeepSeq
import Control.Monad
import Control.Monad.Identity
import Control.Monad.RWS
import Control.Monad.State
import Control.Monad.Writer
import Data.Char
import Data.List
import Data.Maybe
import Data.Semigroup
import qualified Data.List.NonEmpty as NE
import qualified Data.Map as Map
import Test.QuickCheck.All (forAllProperties)
import Test.QuickCheck.Test (maxSuccess, quickCheckWithResult, stdArgs)
type Analysis = AnalyzerM ()
type AnalyzerM a = RWS Parameters [TokenComment] Cache a
nullCheck = const $ return ()
data Checker = Checker {
perScript :: Root -> Analysis,
perToken :: Token -> Analysis
}
runChecker :: Parameters -> Checker -> [TokenComment]
runChecker params checker = notes
where
root = rootNode params
check = perScript checker `composeAnalyzers` (\(Root x) -> void $ doAnalysis (perToken checker) x)
notes = snd $ evalRWS (check $ Root root) params Cache
instance Semigroup Checker where
(<>) x y = Checker {
perScript = perScript x `composeAnalyzers` perScript y,
perToken = perToken x `composeAnalyzers` perToken y
}
instance Monoid Checker where
mempty = Checker {
perScript = nullCheck,
perToken = nullCheck
}
mappend = (Data.Semigroup.<>)
composeAnalyzers :: (a -> Analysis) -> (a -> Analysis) -> a -> Analysis
composeAnalyzers f g x = f x >> g x
data Parameters = Parameters {
-- Whether this script has the 'lastpipe' option set/default.
hasLastpipe :: Bool,
-- Whether this script has the 'inherit_errexit' option set/default.
hasInheritErrexit :: Bool,
-- Whether this script has 'set -e' anywhere.
hasSetE :: Bool,
-- Whether this script has 'set -o pipefail' anywhere.
hasPipefail :: Bool,
-- A linear (bad) analysis of data flow
variableFlow :: [StackData],
-- A map from Id to Token
idMap :: Map.Map Id Token,
-- A map from Id to parent Token
parentMap :: Map.Map Id Token,
-- The shell type, such as Bash or Ksh
shellType :: Shell,
-- True if shell type was forced via flags
shellTypeSpecified :: Bool,
-- The root node of the AST
rootNode :: Token,
-- map from token id to start and end position
tokenPositions :: Map.Map Id (Position, Position),
-- Result from Control Flow Graph analysis (including data flow analysis)
cfgAnalysis :: Maybe CF.CFGAnalysis
} deriving (Show)
-- TODO: Cache results of common AST ops here
data Cache = Cache {}
data Scope = SubshellScope String | NoneScope deriving (Show, Eq)
data StackData =
StackScope Scope
| StackScopeEnd
-- (Base expression, specific position, var name, assigned values)
| Assignment (Token, Token, String, DataType)
| Reference (Token, Token, String)
deriving (Show)
data DataType = DataString DataSource | DataArray DataSource
deriving (Show)
data DataSource =
SourceFrom [Token]
| SourceExternal
| SourceDeclaration
| SourceInteger
| SourceChecked
deriving (Show)
data VariableState = Dead Token String | Alive deriving (Show)
defaultSpec pr = spec {
asShellType = Nothing,
asCheckSourced = False,
asExecutionMode = Executed,
asTokenPositions = prTokenPositions pr
} where spec = newAnalysisSpec (fromJust $ prRoot pr)
pScript s =
let
pSpec = newParseSpec {
psFilename = "script",
psScript = s
}
in runIdentity $ parseScript (mockedSystemInterface []) pSpec
-- For testing. If parsed, returns whether there are any comments
producesComments :: Checker -> String -> Maybe Bool
producesComments c s = do
let pr = pScript s
prRoot pr
let spec = defaultSpec pr
let params = makeParameters spec
return . not . null $ filterByAnnotation spec params $ runChecker params c
makeComment :: Severity -> Id -> Code -> String -> TokenComment
makeComment severity id code note =
newTokenComment {
tcId = id,
tcComment = newComment {
cSeverity = severity,
cCode = code,
cMessage = note
}
}
addComment note = note `deepseq` tell [note]
warn :: MonadWriter [TokenComment] m => Id -> Code -> String -> m ()
warn id code str = addComment $ makeComment WarningC id code str
err id code str = addComment $ makeComment ErrorC id code str
info id code str = addComment $ makeComment InfoC id code str
style id code str = addComment $ makeComment StyleC id code str
errWithFix :: MonadWriter [TokenComment] m => Id -> Code -> String -> Fix -> m ()
errWithFix = addCommentWithFix ErrorC
warnWithFix :: MonadWriter [TokenComment] m => Id -> Code -> String -> Fix -> m ()
warnWithFix = addCommentWithFix WarningC
infoWithFix :: MonadWriter [TokenComment] m => Id -> Code -> String -> Fix -> m ()
infoWithFix = addCommentWithFix InfoC
styleWithFix :: MonadWriter [TokenComment] m => Id -> Code -> String -> Fix -> m ()
styleWithFix = addCommentWithFix StyleC
addCommentWithFix :: MonadWriter [TokenComment] m => Severity -> Id -> Code -> String -> Fix -> m ()
addCommentWithFix severity id code str fix =
addComment $ makeCommentWithFix severity id code str fix
makeCommentWithFix :: Severity -> Id -> Code -> String -> Fix -> TokenComment
makeCommentWithFix severity id code str fix =
let comment = makeComment severity id code str
withFix = comment {
-- If fix is empty, pretend it wasn't there.
tcFix = if null (fixReplacements fix) then Nothing else Just fix
}
in force withFix
-- makeParameters :: CheckSpec -> Parameters
makeParameters spec = params
where
extendedAnalysis = fromMaybe True $ msum [asExtendedAnalysis spec, getExtendedAnalysisDirective root]
params = Parameters {
rootNode = root,
shellType = fromMaybe (determineShell (asFallbackShell spec) root) $ asShellType spec,
hasSetE = containsSetE root,
hasLastpipe =
case shellType params of
Bash -> isOptionSet "lastpipe" root
Dash -> False
BusyboxSh -> False
Sh -> False
Ksh -> True,
hasInheritErrexit =
case shellType params of
Bash -> isOptionSet "inherit_errexit" root
Dash -> True
BusyboxSh -> True
Sh -> True
Ksh -> False,
hasPipefail =
case shellType params of
Bash -> isOptionSet "pipefail" root
Dash -> True
BusyboxSh -> isOptionSet "pipefail" root
Sh -> True
Ksh -> isOptionSet "pipefail" root,
shellTypeSpecified = isJust (asShellType spec) || isJust (asFallbackShell spec),
idMap = getTokenMap root,
parentMap = getParentTree root,
variableFlow = getVariableFlow params root,
tokenPositions = asTokenPositions spec,
cfgAnalysis = do
guard extendedAnalysis
return $ CF.analyzeControlFlow cfParams root
}
cfParams = CF.CFGParameters {
CF.cfLastpipe = hasLastpipe params,
CF.cfPipefail = hasPipefail params
}
root = asScript spec
-- Does this script mention 'set -e' anywhere?
-- Used as a hack to disable certain warnings.
containsSetE root = isNothing $ doAnalysis (guard . not . isSetE) root
where
isSetE t =
case t of
T_Script _ (T_Literal _ str) _ -> str `matches` re
T_SimpleCommand {} ->
t `isUnqualifiedCommand` "set" &&
("errexit" `elem` oversimplify t ||
"e" `elem` map snd (getAllFlags t))
_ -> False
re = mkRegex "[[:space:]]-[^-]*e"
containsSetOption opt root = isNothing $ doAnalysis (guard . not . isPipefail) root
where
isPipefail t =
case t of
T_SimpleCommand {} ->
t `isUnqualifiedCommand` "set" &&
(opt `elem` oversimplify t ||
"o" `elem` map snd (getAllFlags t))
_ -> False
containsShopt shopt root =
isNothing $ doAnalysis (guard . not . isShoptLastPipe) root
where
isShoptLastPipe t =
case t of
T_SimpleCommand {} ->
t `isUnqualifiedCommand` "shopt" &&
(shopt `elem` oversimplify t)
_ -> False
-- Does this script mention 'shopt -s $opt' or 'set -o $opt' anywhere?
isOptionSet opt root = containsShopt opt root || containsSetOption opt root
prop_determineShell0 = determineShellTest "#!/bin/sh" == Sh
prop_determineShell1 = determineShellTest "#!/usr/bin/env ksh" == Ksh
prop_determineShell2 = determineShellTest "" == Bash
prop_determineShell3 = determineShellTest "#!/bin/sh -e" == Sh
prop_determineShell4 = determineShellTest "#!/bin/ksh\n#shellcheck shell=sh\nfoo" == Sh
prop_determineShell5 = determineShellTest "#shellcheck shell=sh\nfoo" == Sh
prop_determineShell6 = determineShellTest "#! /bin/sh" == Sh
prop_determineShell7 = determineShellTest "#! /bin/ash" == Dash
prop_determineShell8 = determineShellTest' (Just Ksh) "#!/bin/sh" == Sh
prop_determineShell9 = determineShellTest "#!/bin/env -S dash -x" == Dash
prop_determineShell10 = determineShellTest "#!/bin/env --split-string= dash -x" == Dash
prop_determineShell11 = determineShellTest "#!/bin/busybox sh" == BusyboxSh -- busybox sh is a specific shell, not posix sh
prop_determineShell12 = determineShellTest "#!/bin/busybox ash" == BusyboxSh
determineShellTest = determineShellTest' Nothing
determineShellTest' fallbackShell = determineShell fallbackShell . fromJust . prRoot . pScript
determineShell fallbackShell t = fromMaybe Bash $
shellForExecutable shellString `mplus` fallbackShell
where
shellString = getCandidate t
getCandidate :: Token -> String
getCandidate t@T_Script {} = fromShebang t
getCandidate (T_Annotation _ annotations s) =
headOrDefault (fromShebang s) [s | ShellOverride s <- annotations]
fromShebang (T_Script _ (T_Literal _ s) _) = executableFromShebang s
-- Given a root node, make a map from Id to parent Token.
-- This is used to populate parentMap in Parameters
getParentTree :: Token -> Map.Map Id Token
getParentTree t =
snd $ execState (doStackAnalysis pre post t) ([], Map.empty)
where
pre t = modify (first ((:) t))
post t = do
(x, map) <- get
case x of
_:rest -> case rest of [] -> put (rest, map)
(x:_) -> put (rest, Map.insert (getId t) x map)
-- Given a root node, make a map from Id to Token
getTokenMap :: Token -> Map.Map Id Token
getTokenMap t =
execState (doAnalysis f t) Map.empty
where
f t = modify (Map.insert (getId t) t)
-- Is this token in a quoting free context? (i.e. would variable expansion split)
-- True: Assignments, [[ .. ]], here docs, already in double quotes
-- False: Regular words
isStrictlyQuoteFree = isQuoteFreeNode True
-- Like above, but also allow some cases where splitting may be desired.
-- True: Like above + for loops
-- False: Like above
isQuoteFree = isQuoteFreeNode False
isQuoteFreeNode strict shell tree t =
isQuoteFreeElement t ||
(fromMaybe False $ msum $ map isQuoteFreeContext $ NE.tail $ getPath tree t)
where
-- Is this node self-quoting in itself?
isQuoteFreeElement t =
case t of
T_Assignment id _ _ _ _ -> assignmentIsQuoting id
T_FdRedirect {} -> True
_ -> False
-- Are any subnodes inherently self-quoting?
isQuoteFreeContext t =
case t of
TC_Nullary _ DoubleBracket _ -> return True
TC_Unary _ DoubleBracket _ _ -> return True
TC_Binary _ DoubleBracket _ _ _ -> return True
TA_Sequence {} -> return True
T_Arithmetic {} -> return True
T_Assignment id _ _ _ _ -> return $ assignmentIsQuoting id
T_Redirecting {} -> return False
T_DoubleQuoted _ _ -> return True
T_DollarDoubleQuoted _ _ -> return True
T_CaseExpression {} -> return True
T_HereDoc {} -> return True
T_DollarBraced {} -> return True
-- When non-strict, pragmatically assume it's desirable to split here
T_ForIn {} -> return (not strict)
T_SelectIn {} -> return (not strict)
_ -> Nothing
-- Check whether this assignment is self-quoting due to being a recognized
-- assignment passed to a Declaration Utility. This will soon be required
-- by POSIX: https://austingroupbugs.net/view.php?id=351
assignmentIsQuoting id = shellParsesParamsAsAssignments || not (isAssignmentParamToCommand id)
shellParsesParamsAsAssignments = shell /= Sh
-- Is this assignment a parameter to a command like export/typeset/etc?
isAssignmentParamToCommand id =
case Map.lookup id tree of
Just (T_SimpleCommand _ _ (_:args)) -> id `elem` (map getId args)
_ -> False
-- Check if a token is a parameter to a certain command by name:
-- Example: isParamTo (parentMap params) "sed" t
isParamTo :: Map.Map Id Token -> String -> Token -> Bool
isParamTo tree cmd =
go
where
go x = case Map.lookup (getId x) tree of
Nothing -> False
Just parent -> check parent
check t =
case t of
T_SingleQuoted _ _ -> go t
T_DoubleQuoted _ _ -> go t
T_NormalWord _ _ -> go t
T_SimpleCommand {} -> isCommand t cmd
T_Redirecting {} -> isCommand t cmd
_ -> False
-- Get the parent command (T_Redirecting) of a Token, if any.
getClosestCommand :: Map.Map Id Token -> Token -> Maybe Token
getClosestCommand tree t =
findFirst findCommand $ NE.toList $ getPath tree t
where
findCommand t =
case t of
T_Redirecting {} -> return True
T_Script {} -> return False
_ -> Nothing
-- Like above, if koala_man knew Haskell when starting this project.
getClosestCommandM t = do
params <- ask
return $ getClosestCommand (parentMap params) t
-- Is the token used as a command name (the first word in a T_SimpleCommand)?
usedAsCommandName tree token = go (getId token) (NE.tail $ getPath tree token)
where
go currentId (T_NormalWord id [word]:rest)
| currentId == getId word = go id rest
go currentId (T_DoubleQuoted id [word]:rest)
| currentId == getId word = go id rest
go currentId (t@(T_SimpleCommand _ _ (word:_)):_) =
getId word == currentId || getId (getCommandTokenOrThis t) == currentId
go _ _ = False
-- Version of the above taking the map from the current context
-- Todo: give this the name "getPath"
getPathM t = do
params <- ask
return $ getPath (parentMap params) t
isParentOf tree parent child =
any (\t -> parentId == getId t) (getPath tree child)
where
parentId = getId parent
parents params = getPath (parentMap params)
-- Find the first match in a list where the predicate is Just True.
-- Stops if it's Just False and ignores Nothing.
findFirst :: (a -> Maybe Bool) -> [a] -> Maybe a
findFirst p = foldr go Nothing
where
go x acc =
case p x of
Just True -> return x
Just False -> Nothing
Nothing -> acc
-- Check whether a word is entirely output from a single command
tokenIsJustCommandOutput t = case t of
T_NormalWord id [T_DollarExpansion _ cmds] -> check cmds
T_NormalWord id [T_DoubleQuoted _ [T_DollarExpansion _ cmds]] -> check cmds
T_NormalWord id [T_Backticked _ cmds] -> check cmds
T_NormalWord id [T_DoubleQuoted _ [T_Backticked _ cmds]] -> check cmds
_ -> False
where
check [x] = not $ isOnlyRedirection x
check _ = False
-- TODO: Replace this with a proper Control Flow Graph
getVariableFlow params t =
reverse $ execState (doStackAnalysis startScope endScope t) []
where
startScope t =
let scopeType = leadType params t
in do
when (scopeType /= NoneScope) $ modify (StackScope scopeType:)
when (assignFirst t) $ setWritten t
endScope t =
let scopeType = leadType params t
in do
setRead t
unless (assignFirst t) $ setWritten t
when (scopeType /= NoneScope) $ modify (StackScopeEnd:)
assignFirst T_ForIn {} = True
assignFirst T_SelectIn {} = True
assignFirst (T_BatsTest {}) = True
assignFirst _ = False
setRead t =
let read = getReferencedVariables (parentMap params) t
in mapM_ (\v -> modify (Reference v:)) read
setWritten t =
let written = getModifiedVariables t
in mapM_ (\v -> modify (Assignment v:)) written
leadType params t =
case t of
T_DollarExpansion _ _ -> SubshellScope "$(..) expansion"
T_Backticked _ _ -> SubshellScope "`..` expansion"
T_Backgrounded _ _ -> SubshellScope "backgrounding &"
T_Subshell _ _ -> SubshellScope "(..) group"
T_BatsTest {} -> SubshellScope "@bats test"
T_CoProcBody _ _ -> SubshellScope "coproc"
T_Redirecting {} ->
if causesSubshell == Just True
then SubshellScope "pipeline"
else NoneScope
_ -> NoneScope
where
parentPipeline = do
parent <- Map.lookup (getId t) (parentMap params)
case parent of
T_Pipeline {} -> return parent
_ -> Nothing
causesSubshell = do
(T_Pipeline _ _ list) <- parentPipeline
return $ case list of
_:_:_ -> not (hasLastpipe params) || getId (last list) /= getId t
_ -> False
getModifiedVariables t =
case t of
T_SimpleCommand _ vars [] ->
[(x, x, name, dataTypeFrom DataString w) | x@(T_Assignment id _ name _ w) <- vars]
T_SimpleCommand {} ->
getModifiedVariableCommand t
TA_Unary _ op v@(TA_Variable _ name _) | "--" `isInfixOf` op || "++" `isInfixOf` op ->
[(t, v, name, DataString SourceInteger)]
TA_Assignment _ op (TA_Variable _ name _) rhs -> do
guard $ op `elem` ["=", "*=", "/=", "%=", "+=", "-=", "<<=", ">>=", "&=", "^=", "|="]
return (t, t, name, DataString SourceInteger)
T_BatsTest {} -> [
(t, t, "lines", DataArray SourceExternal),
(t, t, "status", DataString SourceInteger),
(t, t, "output", DataString SourceExternal)
]
-- Count [[ -v foo ]] as an "assignment".
-- This is to prevent [ -v foo ] being unassigned or unused.
TC_Unary id _ "-v" token -> maybeToList $ do
str <- getVariableForTestDashV token
return (t, token, str, DataString SourceChecked)
TC_Unary _ _ "-n" token -> markAsChecked t token
TC_Unary _ _ "-z" token -> markAsChecked t token
TC_Nullary _ _ token -> markAsChecked t token
T_DollarBraced _ _ l -> maybeToList $ do
let string = concat $ oversimplify l
let modifier = getBracedModifier string
guard $ any (`isPrefixOf` modifier) ["=", ":="]
return (t, t, getBracedReference string, DataString $ SourceFrom [l])
T_FdRedirect _ ('{':var) op -> -- {foo}>&2 modifies foo
[(t, t, takeWhile (/= '}') var, DataString SourceInteger) | not $ isClosingFileOp op]
T_CoProc _ name _ ->
[(t, t, fromMaybe "COPROC" name, DataArray SourceInteger)]
--Points to 'for' rather than variable
T_ForIn id str [] _ -> [(t, t, str, DataString SourceExternal)]
T_ForIn id str words _ -> [(t, t, str, DataString $ SourceFrom words)]
T_SelectIn id str words _ -> [(t, t, str, DataString $ SourceFrom words)]
_ -> []
where
markAsChecked place token = mapMaybe (f place) $ getWordParts token
f place t = case t of
T_DollarBraced _ _ l ->
let str = getBracedReference $ concat $ oversimplify l in do
guard $ isVariableName str
return (place, t, str, DataString SourceChecked)
_ -> Nothing
-- Consider 'export/declare -x' a reference, since it makes the var available
getReferencedVariableCommand base@(T_SimpleCommand _ _ (T_NormalWord _ (T_Literal _ x:_):rest)) =
case x of
"declare" -> forDeclare
"typeset" -> forDeclare
"export" -> if "f" `elem` flags
then []
else concatMap getReference rest
"local" -> if "x" `elem` flags
then concatMap getReference rest
else []
"trap" ->
case rest of
head:_ -> map (\x -> (base, head, x)) $ getVariablesFromLiteralToken head
_ -> []
"alias" -> [(base, token, name) | token <- rest, name <- getVariablesFromLiteralToken token]
_ -> []
where
forDeclare =
if
any (`elem` flags) ["x", "p"] &&
(not $ any (`elem` flags) ["f", "F"])
then concatMap getReference rest
else []
getReference t@(T_Assignment _ _ name _ value) = [(t, t, name)]
getReference t@(T_NormalWord _ [T_Literal _ name]) | not ("-" `isPrefixOf` name) = [(t, t, name)]
getReference _ = []
flags = map snd $ getAllFlags base
getReferencedVariableCommand _ = []
-- The function returns a tuple consisting of four items describing an assignment.
-- Given e.g. declare foo=bar
-- (
-- BaseCommand :: Token, -- The command/structure assigning the variable, i.e. declare foo=bar
-- AssignmentToken :: Token, -- The specific part that assigns this variable, i.e. foo=bar
-- VariableName :: String, -- The variable name, i.e. foo
-- VariableValue :: DataType -- A description of the value being assigned, i.e. "Literal string with value foo"
-- )
getModifiedVariableCommand base@(T_SimpleCommand id cmdPrefix (T_NormalWord _ (T_Literal _ x:_):rest)) =
filter (\(_,_,s,_) -> not ("-" `isPrefixOf` s)) $
case x of
"builtin" ->
getModifiedVariableCommand $ T_SimpleCommand id cmdPrefix rest
"read" ->
let fallback = catMaybes $ takeWhile isJust (reverse $ map getLiteral rest)
in fromMaybe fallback $ do
parsed <- getGnuOpts flagsForRead rest
case lookup "a" parsed of
Just (_, var) -> (:[]) <$> getLiteralArray var
Nothing -> return $ catMaybes $
map (getLiteral . snd . snd) $ filter (null . fst) parsed
"getopts" ->
case rest of
opts:var:_ -> maybeToList $ getLiteral var
_ -> []
"let" -> concatMap letParamToLiteral rest
"export" ->
if "f" `elem` flags then [] else concatMap getModifierParamString rest
"declare" -> forDeclare
"typeset" -> forDeclare
"local" -> concatMap getModifierParamString rest
"readonly" ->
if any (`elem` flags) ["f", "p"]
then []
else concatMap getModifierParamString rest
"set" -> maybeToList $ do
params <- getSetParams rest
return (base, base, "@", DataString $ SourceFrom params)
"printf" -> maybeToList $ getPrintfVariable rest
"wait" -> maybeToList $ getWaitVariable rest
"mapfile" -> maybeToList $ getMapfileArray base rest
"readarray" -> maybeToList $ getMapfileArray base rest
"DEFINE_boolean" -> maybeToList $ getFlagVariable rest
"DEFINE_float" -> maybeToList $ getFlagVariable rest
"DEFINE_integer" -> maybeToList $ getFlagVariable rest
"DEFINE_string" -> maybeToList $ getFlagVariable rest
_ -> []
where
flags = map snd $ getAllFlags base
stripEquals s = drop 1 $ dropWhile (/= '=') s
stripEqualsFrom (T_NormalWord id1 (T_Literal id2 s:rs)) =
T_NormalWord id1 (T_Literal id2 (stripEquals s):rs)
stripEqualsFrom (T_NormalWord id1 [T_DoubleQuoted id2 [T_Literal id3 s]]) =
T_NormalWord id1 [T_DoubleQuoted id2 [T_Literal id3 (stripEquals s)]]
stripEqualsFrom t = t
forDeclare = if any (`elem` flags) ["F", "f", "p"] then [] else declaredVars
declaredVars = concatMap (getModifierParam defaultType) rest
where
defaultType = if any (`elem` flags) ["a", "A"] then DataArray else DataString
getLiteralOfDataType t d = do
s <- getLiteralString t
when ("-" `isPrefixOf` s) $ fail "argument"
return (base, t, s, d)
getLiteral t = getLiteralOfDataType t (DataString SourceExternal)
getLiteralArray t = getLiteralOfDataType t (DataArray SourceExternal)
getModifierParamString = getModifierParam DataString
getModifierParam def t@(T_Assignment _ _ name _ value) =
[(base, t, name, dataTypeFrom def value)]
getModifierParam def t@T_NormalWord {} = maybeToList $ do
name <- getLiteralString t
guard $ isVariableName name
return (base, t, name, def SourceDeclaration)
getModifierParam _ _ = []
letParamToLiteral token =
if null var
then []
else [(base, token, var, DataString $ SourceFrom [stripEqualsFrom token])]
where var = takeWhile isVariableChar $ dropWhile (`elem` "+-") $ concat $ oversimplify token
getSetParams (t:_:rest) | getLiteralString t == Just "-o" = getSetParams rest
getSetParams (t:rest) =
let s = getLiteralString t in
case s of
Just "--" -> return rest
Just ('-':_) -> getSetParams rest
_ -> return (t:fromMaybe [] (getSetParams rest))
getSetParams [] = Nothing
getPrintfVariable list = getFlagAssignedVariable "v" (SourceFrom list) $ getBsdOpts "v:" list
getWaitVariable list = getFlagAssignedVariable "p" SourceInteger $ return $ getGenericOpts list
getFlagAssignedVariable str dataSource maybeFlags = do
flags <- maybeFlags
(_, (flag, value)) <- find ((== str) . fst) flags
variableName <- getLiteralStringExt (const $ return "!") value
let (baseName, index) = span (/= '[') variableName
return (base, value, baseName, (if null index then DataString else DataArray) dataSource)
-- mapfile has some curious syntax allowing flags plus 0..n variable names
-- where only the first non-option one is used if any.
getMapfileArray base rest = parseArgs `mplus` fallback
where
parseArgs :: Maybe (Token, Token, String, DataType)
parseArgs = do
args <- getGnuOpts "d:n:O:s:u:C:c:t" rest
case [y | ("",(_,y)) <- args] of
[] ->
return (base, base, "MAPFILE", DataArray SourceExternal)
first:_ -> do
name <- getLiteralString first
guard $ isVariableName name
return (base, first, name, DataArray SourceExternal)
-- If arg parsing fails (due to bad or new flags), get the last variable name
fallback :: Maybe (Token, Token, String, DataType)
fallback = do
(name, token) <- listToMaybe . mapMaybe f $ reverse rest
return (base, token, name, DataArray SourceExternal)
f arg = do
name <- getLiteralString arg
guard $ isVariableName name
return (name, arg)
-- get the FLAGS_ variable created by a shflags DEFINE_ call
getFlagVariable (n:v:_) = do
name <- getLiteralString n
return (base, n, "FLAGS_" ++ name, DataString $ SourceExternal)
getFlagVariable _ = Nothing
getModifiedVariableCommand _ = []
-- Given a NormalWord like foo or foo[$bar], get foo.
-- Primarily used to get references for [[ -v foo[bar] ]]
getVariableForTestDashV :: Token -> Maybe String
getVariableForTestDashV t = do
str <- takeWhile ('[' /=) <$> getLiteralStringExt toStr t
guard $ isVariableName str
return str
where
-- foo[bar] gets parsed with [bar] as a glob, so undo that
toStr (T_Glob _ s) = return s
-- Turn foo[$x] into foo[\0] so that we can get the constant array name
-- in a non-constant expression (while filtering out foo$x[$y])
toStr _ = return "\0"
getReferencedVariables parents t =
case t of
T_DollarBraced id _ l -> let str = concat $ oversimplify l in
(t, t, getBracedReference str) :
map (\x -> (l, l, x)) (
getIndexReferences str
++ getOffsetReferences (getBracedModifier str))
TA_Variable id name _ ->
if isArithmeticAssignment t
then []
else [(t, t, name)]
T_Assignment id mode str _ word ->
[(t, t, str) | mode == Append] ++ specialReferences str t word
TC_Unary id _ "-v" token -> getIfReference t token
TC_Unary id _ "-R" token -> getIfReference t token
TC_Binary id DoubleBracket op lhs rhs ->
if isDereferencingBinaryOp op
then concatMap (getIfReference t) [lhs, rhs]
else []
T_BatsTest {} -> [ -- pretend @test references vars to avoid warnings
(t, t, "lines"),
(t, t, "status"),
(t, t, "output")
]
T_FdRedirect _ ('{':var) op -> -- {foo}>&- references and closes foo
[(t, t, takeWhile (/= '}') var) | isClosingFileOp op]
x -> getReferencedVariableCommand x
where
-- Try to reduce false positives for unused vars only referenced from evaluated vars
specialReferences name base word =
if name `elem` [
"PS1", "PS2", "PS3", "PS4",
"PROMPT_COMMAND"
]
then
map (\x -> (base, base, x)) $
getVariablesFromLiteralToken word
else []
literalizer t = case t of
T_Glob _ s -> return s -- Also when parsed as globs
_ -> []
getIfReference context token = maybeToList $ do
str <- getVariableForTestDashV token
return (context, token, getBracedReference str)
isArithmeticAssignment t = case getPath parents t of
this NE.:| TA_Assignment _ "=" lhs _ :_ -> lhs == t
_ -> False
isDereferencingBinaryOp = (`elem` ["-eq", "-ne", "-lt", "-le", "-gt", "-ge"])
dataTypeFrom defaultType v = (case v of T_Array {} -> DataArray; _ -> defaultType) $ SourceFrom [v]
--- Command specific checks
-- Compare a command to a string: t `isCommand` "sed" (also matches /usr/bin/sed)
isCommand token str = isCommandMatch token (\cmd -> cmd == str || ('/' : str) `isSuffixOf` cmd)
-- Compare a command to a literal. Like above, but checks full path.
isUnqualifiedCommand token str = isCommandMatch token (== str)
isCommandMatch token matcher = maybe False
matcher (getCommandName token)
-- Does this regex look like it was intended as a glob?
-- True: *foo*
-- False: .*foo.*
isConfusedGlobRegex :: String -> Bool
isConfusedGlobRegex ('*':_) = True
isConfusedGlobRegex [x,'*'] | x `notElem` "\\." = True
isConfusedGlobRegex _ = False
getVariablesFromLiteralToken token =
getVariablesFromLiteral (getLiteralStringDef " " token)
-- Try to get referenced variables from a literal string like "$foo"
-- Ignores tons of cases like arithmetic evaluation and array indices.
prop_getVariablesFromLiteral1 =
getVariablesFromLiteral "$foo${bar//a/b}$BAZ" == ["foo", "bar", "BAZ"]
getVariablesFromLiteral string =
map head $ matchAllSubgroups variableRegex string
where
variableRegex = mkRegex "\\$\\{?([A-Za-z0-9_]+)"
-- Run a command if the shell is in the given list
whenShell l c = do
params <- ask
when (shellType params `elem` l ) c
filterByAnnotation asSpec params =
filter (not . shouldIgnore)
where
token = asScript asSpec
shouldIgnore note =
any (shouldIgnoreFor (getCode note)) $
getPath parents (T_Bang $ tcId note)
shouldIgnoreFor _ T_Include {} = not $ asCheckSourced asSpec
shouldIgnoreFor code t = isAnnotationIgnoringCode code t
parents = parentMap params
getCode = cCode . tcComment
shouldIgnoreCode params code t =
any (isAnnotationIgnoringCode code) $
getPath (parentMap params) t
-- Is this a ${#anything}, to get string length or array count?
isCountingReference (T_DollarBraced id _ token) =
case concat $ oversimplify token of
'#':_ -> True
_ -> False
isCountingReference _ = False
-- FIXME: doesn't handle ${a:+$var} vs ${a:+"$var"}
isQuotedAlternativeReference t =
case t of
T_DollarBraced _ _ l ->
getBracedModifier (concat $ oversimplify l) `matches` re
_ -> False
where
re = mkRegex "(^|\\]):?\\+"
supportsArrays Bash = True
supportsArrays Ksh = True
supportsArrays _ = False
-- Returns true if the shell is Bash or Ksh (sorry for the name, Ksh)
isBashLike :: Parameters -> Bool
isBashLike params =
case shellType params of
Bash -> True
Ksh -> True
Dash -> False
BusyboxSh -> False
Sh -> False
isTrueAssignmentSource c =
case c of
DataString SourceChecked -> False
DataString SourceDeclaration -> False
DataArray SourceChecked -> False
DataArray SourceDeclaration -> False
_ -> True
modifiesVariable params token name =
or $ map check flow
where
flow = getVariableFlow params token
check t =
case t of
Assignment (_, _, n, source) -> isTrueAssignmentSource source && n == name
_ -> False
return []
runTests = $( [| $(forAllProperties) (quickCheckWithResult (stdArgs { maxSuccess = 1 }) ) |])