shellcheck/ShellCheck/AnalyzerLib.hs

731 lines
26 KiB
Haskell

{-
Copyright 2012-2015 Vidar Holen
This file is part of ShellCheck.
http://www.vidarholen.net/contents/shellcheck
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 <http://www.gnu.org/licenses/>.
-}
{-# LANGUAGE TemplateHaskell #-}
{-# LANGUAGE FlexibleContexts #-}
module ShellCheck.AnalyzerLib where
import ShellCheck.AST
import ShellCheck.ASTLib
import ShellCheck.Data
import ShellCheck.Interface
import ShellCheck.Parser
import ShellCheck.Regex
import Control.Arrow (first)
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 qualified Data.Map as Map
import Test.QuickCheck.All (forAllProperties)
import Test.QuickCheck.Test (quickCheckWithResult, stdArgs, maxSuccess)
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 Monoid Checker where
mempty = Checker {
perScript = nullCheck,
perToken = nullCheck
}
mappend x y = Checker {
perScript = perScript x `composeAnalyzers` perScript y,
perToken = perToken x `composeAnalyzers` perToken y
}
composeAnalyzers :: (a -> Analysis) -> (a -> Analysis) -> a -> Analysis
composeAnalyzers f g x = f x >> g x
data Parameters = Parameters {
variableFlow :: [StackData],
parentMap :: Map.Map Id Token,
shellType :: Shell,
shellTypeSpecified :: Bool,
rootNode :: Token
}
-- 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
deriving (Show)
data VariableState = Dead Token String | Alive deriving (Show)
defaultSpec root = AnalysisSpec {
asScript = root,
asShellType = Nothing,
asExecutionMode = Executed
}
pScript s =
let
pSpec = ParseSpec {
psFilename = "script",
psScript = s
}
in prRoot . runIdentity $ parseScript (mockedSystemInterface []) pSpec
-- For testing. If parsed, returns whether there are any comments
producesComments :: Checker -> String -> Maybe Bool
producesComments c s = do
root <- pScript s
let spec = defaultSpec root
let params = makeParameters spec
return . not . null $ runChecker params c
makeComment :: Severity -> Id -> Code -> String -> TokenComment
makeComment severity id code note =
TokenComment id $ Comment severity code note
addComment note = 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
makeParameters spec =
let params = Parameters {
rootNode = root,
shellType = fromMaybe (determineShell root) $ asShellType spec,
shellTypeSpecified = isJust $ asShellType spec,
parentMap = getParentTree root,
variableFlow =
getVariableFlow (shellType params) (parentMap params) root
} in params
where root = asScript spec
prop_determineShell0 = determineShell (fromJust $ pScript "#!/bin/sh") == Sh
prop_determineShell1 = determineShell (fromJust $ pScript "#!/usr/bin/env ksh") == Ksh
prop_determineShell2 = determineShell (fromJust $ pScript "") == Bash
prop_determineShell3 = determineShell (fromJust $ pScript "#!/bin/sh -e") == Sh
prop_determineShell4 = determineShell (fromJust $ pScript
"#!/bin/ksh\n#shellcheck shell=sh\nfoo") == Sh
prop_determineShell5 = determineShell (fromJust $ pScript
"#shellcheck shell=sh\nfoo") == Sh
prop_determineShell6 = determineShell (fromJust $ pScript "#! /bin/sh") == Sh
prop_determineShell7 = determineShell (fromJust $ pScript "#! /bin/ash") == Dash
determineShell t = fromMaybe Bash $ do
shellString <- foldl mplus Nothing $ getCandidates t
shellForExecutable shellString
where
forAnnotation t =
case t of
(ShellOverride s) -> return s
_ -> fail ""
getCandidates :: Token -> [Maybe String]
getCandidates t@(T_Script {}) = [Just $ fromShebang t]
getCandidates (T_Annotation _ annotations s) =
map forAnnotation annotations ++
[Just $ fromShebang s]
fromShebang (T_Script _ s t) = executableFromShebang s
-- Given a string like "/bin/bash" or "/usr/bin/env dash",
-- return the shell basename like "bash" or "dash"
executableFromShebang :: String -> String
executableFromShebang = shellFor
where
shellFor s | "/env " `isInfixOf` s = head (drop 1 (words s)++[""])
shellFor s | ' ' `elem` s = shellFor $ takeWhile (/= ' ') s
shellFor s = reverse . takeWhile (/= '/') . reverse $ s
--- Context seeking
getParentTree t =
snd . snd $ runState (doStackAnalysis pre post t) ([], Map.empty)
where
pre t = modify (first ((:) t))
post t = do
(_:rest, map) <- get
case rest of [] -> put (rest, map)
(x:_) -> put (rest, Map.insert (getId t) x map)
getTokenMap t =
execState (doAnalysis f t) Map.empty
where
f t = modify (Map.insert (getId t) t)
-- Is this node self quoting for a regular element?
isQuoteFree = isQuoteFreeNode False
-- Is this node striclty self quoting, for array expansions
isStrictlyQuoteFree = isQuoteFreeNode True
isQuoteFreeNode strict tree t =
(isQuoteFreeElement t == Just True) ||
head (mapMaybe isQuoteFreeContext (drop 1 $ getPath tree t) ++ [False])
where
-- Is this node self-quoting in itself?
isQuoteFreeElement t =
case t of
T_Assignment {} -> return True
T_FdRedirect {} -> return True
_ -> Nothing
-- 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 {} -> return True
T_Redirecting {} -> return $
if strict then False else
-- Not true, just a hack to prevent warning about non-expansion refs
any (isCommand t) ["local", "declare", "typeset", "export", "trap", "readonly"]
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
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
getClosestCommand tree t =
msum . map getCommand $ getPath tree t
where
getCommand t@(T_Redirecting {}) = return t
getCommand _ = Nothing
getClosestCommandM t = do
tree <- asks parentMap
return $ getClosestCommand tree t
usedAsCommandName tree token = go (getId token) (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_SimpleCommand _ _ (word:_):_)
| currentId == getId word = True
go _ _ = False
-- A list of the element and all its parents
getPath tree t = t :
case Map.lookup (getId t) tree of
Nothing -> []
Just parent -> getPath tree parent
-- Version of the above taking the map from the current context
-- Todo: give this the name "getPath"
getPathM t = do
map <- asks parentMap
return $ getPath map t
isParentOf tree parent child =
elem (getId parent) . map getId $ getPath tree child
parents params = getPath (parentMap params)
pathTo t = do
parents <- reader parentMap
return $ getPath parents t
-- 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 shell parents t =
let (_, stack) = runState (doStackAnalysis startScope endScope t) []
in reverse stack
where
startScope t =
let scopeType = leadType shell parents t
in do
when (scopeType /= NoneScope) $ modify (StackScope scopeType:)
when (assignFirst t) $ setWritten t
endScope t =
let scopeType = leadType shell parents t
in do
setRead t
unless (assignFirst t) $ setWritten t
when (scopeType /= NoneScope) $ modify (StackScopeEnd:)
assignFirst (T_ForIn {}) = True
assignFirst (T_SelectIn {}) = True
assignFirst _ = False
setRead t =
let read = getReferencedVariables parents t
in mapM_ (\v -> modify (Reference v:)) read
setWritten t =
let written = getModifiedVariables t
in mapM_ (\v -> modify (Assignment v:)) written
leadType shell parents t =
case t of
T_DollarExpansion _ _ -> SubshellScope "$(..) expansion"
T_Backticked _ _ -> SubshellScope "`..` expansion"
T_Backgrounded _ _ -> SubshellScope "backgrounding &"
T_Subshell _ _ -> SubshellScope "(..) group"
T_CoProcBody _ _ -> SubshellScope "coproc"
T_Redirecting {} ->
if fromMaybe False causesSubshell
then SubshellScope "pipeline"
else NoneScope
_ -> NoneScope
where
parentPipeline = do
parent <- Map.lookup (getId t) parents
case parent of
T_Pipeline {} -> return parent
_ -> Nothing
causesSubshell = do
(T_Pipeline _ _ list) <- parentPipeline
if length list <= 1
then return False
else if lastCreatesSubshell
then return True
else return . not $ (getId . head $ reverse list) == getId t
lastCreatesSubshell =
case shell of
Bash -> True
Dash -> True
Sh -> True
Ksh -> False
getModifiedVariables t =
case t of
T_SimpleCommand _ vars [] ->
concatMap (\x -> case x of
T_Assignment id _ name _ w ->
[(x, x, name, dataTypeFrom DataString w)]
_ -> []
) vars
c@(T_SimpleCommand {}) ->
getModifiedVariableCommand c
TA_Unary _ "++|" var -> maybeToList $ do
name <- getLiteralString var
return (t, t, name, DataString $ SourceFrom [t])
TA_Unary _ "|++" var -> maybeToList $ do
name <- getLiteralString var
return (t, t, name, DataString $ SourceFrom [t])
TA_Assignment _ op lhs rhs -> maybeToList $ do
guard $ op `elem` ["=", "*=", "/=", "%=", "+=", "-=", "<<=", ">>=", "&=", "^=", "|="]
name <- getLiteralString lhs
return (t, t, name, DataString $ SourceFrom [rhs])
T_DollarBraced _ l -> maybeToList $ do
let string = bracedString t
let modifier = getBracedModifier string
guard $ ":=" `isPrefixOf` modifier
return (t, t, getBracedReference string, DataString $ SourceFrom [l])
t@(T_FdRedirect _ ('{':var) op) -> -- {foo}>&2 modifies foo
[(t, t, takeWhile (/= '}') var, DataString SourceInteger) | not $ isClosingFileOp op]
t@(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)]
_ -> []
isClosingFileOp op =
case op of
T_IoFile _ (T_GREATAND _) (T_NormalWord _ [T_Literal _ "-"]) -> True
T_IoFile _ (T_LESSAND _) (T_NormalWord _ [T_Literal _ "-"]) -> True
_ -> False
-- 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
"export" -> if "f" `elem` flags
then []
else concatMap getReference rest
"declare" -> if any (`elem` flags) ["x", "p"]
then concatMap getReference rest
else []
"readonly" ->
if any (`elem` flags) ["f", "p"]
then []
else concatMap getReference rest
"trap" ->
case rest of
head:_ -> map (\x -> (head, head, x)) $ getVariablesFromLiteralToken head
_ -> []
_ -> []
where
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 _ = []
getModifiedVariableCommand base@(T_SimpleCommand _ _ (T_NormalWord _ (T_Literal _ x:_):rest)) =
filter (\(_,_,s,_) -> not ("-" `isPrefixOf` s)) $
case x of
"read" ->
let params = map getLiteral rest in
catMaybes . takeWhile isJust . reverse $ params
"getopts" ->
case rest of
opts:var:_ -> maybeToList $ getLiteral var
_ -> []
"let" -> concatMap letParamToLiteral rest
"export" ->
if "f" `elem` flags then [] else concatMap getModifierParamString rest
"declare" -> if any (`elem` flags) ["F", "f", "p"] then [] else declaredVars
"typeset" -> declaredVars
"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
"mapfile" -> maybeToList $ getMapfileArray base rest
"readarray" -> maybeToList $ getMapfileArray base rest
_ -> []
where
flags = map snd $ getAllFlags base
stripEquals s = let rest = dropWhile (/= '=') s in
if rest == "" then "" else tail rest
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
declaredVars = concatMap (getModifierParam defaultType) rest
where
defaultType = if any (`elem` flags) ["a", "A"] then DataArray else DataString
getLiteral t = do
s <- getLiteralString t
when ("-" `isPrefixOf` s) $ fail "argument"
return (base, t, s, DataString 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 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 = f $ map (\x -> (x, getLiteralString x)) list
where
f ((_, Just "-v") : (t, Just var) : _) = return (base, t, var, DataString $ SourceFrom list)
f (_:rest) = f rest
f [] = fail "not found"
-- mapfile has some curious syntax allowing flags plus 0..n variable names
-- where only the first non-option one is used if any. Here we cheat and
-- just get the last one, if it's a variable name.
getMapfileArray base arguments = do
lastArg <- listToMaybe (reverse arguments)
name <- getLiteralString lastArg
guard $ isVariableName name
return (base, lastArg, name, DataArray SourceExternal)
getModifiedVariableCommand _ = []
getIndexReferences s = fromMaybe [] $ do
match <- matchRegex re s
index <- match !!! 0
return $ matchAllStrings variableNameRegex index
where
re = mkRegex "(\\[.*\\])"
getOffsetReferences mods = fromMaybe [] $ do
match <- matchRegex re mods
offsets <- match !!! 0
return $ matchAllStrings variableNameRegex offsets
where
re = mkRegex "^ *:(.*)"
getReferencedVariables parents t =
case t of
T_DollarBraced id l -> let str = bracedString t in
(t, t, getBracedReference str) :
map (\x -> (l, l, x)) (
getIndexReferences str
++ getOffsetReferences (getBracedModifier str))
TA_Expansion id _ ->
if isArithmeticAssignment t
then []
else getIfReference t t
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 isDereferencing op
then concatMap (getIfReference t) [lhs, rhs]
else []
t@(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 (TA_Index {}) = return "" -- x[0] becomes a reference of x
literalizer _ = Nothing
getIfReference context token = maybeToList $ do
str <- getLiteralStringExt literalizer token
guard . not $ null str
when (isDigit $ head str) $ fail "is a number"
return (context, token, getBracedReference str)
isDereferencing = (`elem` ["-eq", "-ne", "-lt", "-le", "-gt", "-ge"])
isArithmeticAssignment t = case getPath parents t of
this: TA_Assignment _ "=" lhs _ :_ -> lhs == t
_ -> False
dataTypeFrom defaultType v = (case v of T_Array {} -> DataArray; _ -> defaultType) $ SourceFrom [v]
--- Command specific checks
isCommand token str = isCommandMatch token (\cmd -> cmd == str || ('/' : str) `isSuffixOf` cmd)
isUnqualifiedCommand token str = isCommandMatch token (== str)
isCommandMatch token matcher = fromMaybe False $ do
cmd <- getCommandName token
return $ matcher cmd
isConfusedGlobRegex ('*':_) = True
isConfusedGlobRegex [x,'*'] | x /= '\\' = True
isConfusedGlobRegex _ = False
isVariableStartChar x = x == '_' || isAsciiLower x || isAsciiUpper x
isVariableChar x = isVariableStartChar x || isDigit x
variableNameRegex = mkRegex "[_a-zA-Z][_a-zA-Z0-9]*"
prop_isVariableName1 = isVariableName "_fo123"
prop_isVariableName2 = not $ isVariableName "4"
prop_isVariableName3 = not $ isVariableName "test: "
isVariableName (x:r) = isVariableStartChar x && all isVariableChar r
isVariableName _ = False
getVariablesFromLiteralToken token =
getVariablesFromLiteral (fromJust $ getLiteralStringExt (const $ return " ") 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 (!! 0) $ matchAllSubgroups variableRegex string
where
variableRegex = mkRegex "\\$\\{?([A-Za-z0-9_]+)"
prop_getBracedReference1 = getBracedReference "foo" == "foo"
prop_getBracedReference2 = getBracedReference "#foo" == "foo"
prop_getBracedReference3 = getBracedReference "#" == "#"
prop_getBracedReference4 = getBracedReference "##" == "#"
prop_getBracedReference5 = getBracedReference "#!" == "!"
prop_getBracedReference6 = getBracedReference "!#" == "#"
prop_getBracedReference7 = getBracedReference "!foo#?" == "foo"
prop_getBracedReference8 = getBracedReference "foo-bar" == "foo"
prop_getBracedReference9 = getBracedReference "foo:-bar" == "foo"
prop_getBracedReference10= getBracedReference "foo: -1" == "foo"
prop_getBracedReference11= getBracedReference "!os*" == ""
prop_getBracedReference12= getBracedReference "!os?bar**" == ""
prop_getBracedReference13= getBracedReference "foo[bar]" == "foo"
getBracedReference s = fromMaybe s $
nameExpansion s `mplus` takeName noPrefix `mplus` getSpecial noPrefix `mplus` getSpecial s
where
noPrefix = dropPrefix s
dropPrefix (c:rest) = if c `elem` "!#" then rest else c:rest
dropPrefix "" = ""
takeName s = do
let name = takeWhile isVariableChar s
guard . not $ null name
return name
getSpecial (c:_) =
if c `elem` "*@#?-$!" then return [c] else fail "not special"
getSpecial _ = fail "empty"
nameExpansion ('!':rest) = do -- e.g. ${!foo*bar*}
let suffix = dropWhile isVariableChar rest
guard $ suffix /= rest -- e.g. ${!@}
first <- suffix !!! 0
guard $ first `elem` "*?"
return ""
nameExpansion _ = Nothing
prop_getBracedModifier1 = getBracedModifier "foo:bar:baz" == ":bar:baz"
prop_getBracedModifier2 = getBracedModifier "!var:-foo" == ":-foo"
prop_getBracedModifier3 = getBracedModifier "foo[bar]" == "[bar]"
getBracedModifier s = fromMaybe "" . listToMaybe $ do
let var = getBracedReference s
a <- dropModifier s
dropPrefix var a
where
dropPrefix [] t = return t
dropPrefix (a:b) (c:d) | a == c = dropPrefix b d
dropPrefix _ _ = []
dropModifier (c:rest) | c `elem` "#!" = [rest, c:rest]
dropModifier x = [x]
-- Useful generic functions
potentially :: Monad m => Maybe (m ()) -> m ()
potentially = fromMaybe (return ())
headOrDefault _ (a:_) = a
headOrDefault def _ = def
(!!!) list i =
case drop i list of
[] -> Nothing
(r:_) -> Just r
-- Run a command if the shell is in the given list
whenShell l c = do
shell <- asks shellType
when (shell `elem` l ) c
filterByAnnotation token =
filter (not . shouldIgnore)
where
idFor (TokenComment id _) = id
shouldIgnore note =
any (shouldIgnoreFor (getCode note)) $
getPath parents (T_Bang $ idFor note)
shouldIgnoreFor num (T_Annotation _ anns _) =
any hasNum anns
where
hasNum (DisableComment ts) = num == ts
hasNum _ = False
shouldIgnoreFor _ (T_Include {}) = True -- Ignore included files
shouldIgnoreFor _ _ = False
parents = getParentTree token
getCode (TokenComment _ (Comment _ c _)) = c
return []
runTests = $( [| $(forAllProperties) (quickCheckWithResult (stdArgs { maxSuccess = 1 }) ) |])