Warn about missing shebangs.

README.md

@@ -16,7 +16,7 @@ The goals of ShellCheck are:
   - To point out subtle caveats, corner cases and pitfalls, that may cause an
     advanced user's otherwise working script to fail under future circumstances.
 
-ShellCheck is written in Haskell, and requires at least 1 GB of RAM to compile.
+ShellCheck is written in Haskell, and requires 2 GB of memory to compile.
 
 ## Installing
 

ShellCheck.cabal

@@ -47,6 +47,7 @@ library
       ShellCheck.Analytics
       ShellCheck.AST
       ShellCheck.Data
+      ShellCheck.Options
       ShellCheck.Parser
       ShellCheck.Simple
     other-modules:

ShellCheck/Analytics.hs

@@ -16,7 +16,7 @@
     along with this program.  If not, see <http://www.gnu.org/licenses/>.
 -}
 {-# LANGUAGE TemplateHaskell #-}
-module ShellCheck.Analytics (AnalysisOption(..), filterByAnnotation, runAnalytics, shellForExecutable, runTests) where
+module ShellCheck.Analytics (AnalysisOptions(..), defaultAnalysisOptions, filterByAnnotation, runAnalytics, shellForExecutable, runTests) where
 
 import Control.Arrow (first)
 import Control.Monad
@@ -29,23 +29,19 @@ import Data.List
 import Data.Maybe
 import Debug.Trace
 import ShellCheck.AST
+import ShellCheck.Options
 import ShellCheck.Data
 import ShellCheck.Parser hiding (runTests)
 import Text.Regex
 import qualified Data.Map as Map
 import Test.QuickCheck.All (quickCheckAll)
 
-data Shell = Ksh | Zsh | Sh | Bash
-    deriving (Show, Eq)
-
 data Parameters = Parameters {
     variableFlow :: [StackData],
     parentMap :: Map.Map Id Token,
     shellType :: Shell
     }
 
-data AnalysisOption = ForceShell Shell
-
 -- Checks that are run on the AST root
 treeChecks :: [Parameters -> Token -> [Note]]
 treeChecks = [
@@ -55,11 +51,12 @@ treeChecks = [
     ,subshellAssignmentCheck
     ,checkSpacefulness
     ,checkQuotesInLiterals
-    ,checkShebang
+    ,checkShebangParameters
     ,checkFunctionsUsedExternally
     ,checkUnusedAssignments
     ,checkUnpassedInFunctions
     ,checkArrayWithoutIndex
+    ,checkShebang
     ]
 
 checksFor Sh = [
@@ -81,24 +78,19 @@ checksFor Bash = [
     ,checkForDecimals
     ]
 
-runAnalytics :: [AnalysisOption] -> Token -> [Note]
+runAnalytics :: AnalysisOptions -> Token -> [Note]
 runAnalytics options root = runList options root treeChecks
 
 runList options root list = notes
     where
         params = Parameters {
-                shellType = getShellOption,
+                shellType = fromMaybe (determineShell root) $ optionShellType options,
                 parentMap = getParentTree root,
                 variableFlow = getVariableFlow (shellType params) (parentMap params) root
         }
-        notes = concatMap (\f -> f params root) list
+        notes = filter (\c -> getCode c `notElem` optionExcludes options) $ concatMap (\f -> f params root) list
+        getCode (Note _ _ c _) = c
 
-        getShellOption =
-            fromMaybe (determineShell root) . msum $
-                map (\option ->
-                    case option of
-                        ForceShell x -> return x
-                        ) options
 
 checkList l t = concatMap (\f -> f t) l
 
@@ -353,21 +345,21 @@ getFlags _ = []
         [] -> Nothing
         (r:_) -> Just r
 
-verify :: (Parameters -> Token -> Writer [a] ()) -> String -> Bool
+verify :: (Parameters -> Token -> Writer [Note] ()) -> String -> Bool
 verify f s = checkNode f s == Just True
 
-verifyNot :: (Parameters -> Token -> Writer [a] ()) -> String -> Bool
+verifyNot :: (Parameters -> Token -> Writer [Note] ()) -> String -> Bool
 verifyNot f s = checkNode f s == Just False
 
-verifyTree :: (Parameters -> Token -> [a]) -> String -> Bool
+verifyTree :: (Parameters -> Token -> [Note]) -> String -> Bool
 verifyTree f s = checkTree f s == Just True
 
-verifyNotTree :: (Parameters -> Token -> [a]) -> String -> Bool
+verifyNotTree :: (Parameters -> Token -> [Note]) -> String -> Bool
 verifyNotTree f s = checkTree f s == Just False
 
 checkNode f = checkTree (runNodeAnalysis f)
 checkTree f s = case parseShell "-" s of
-        (ParseResult (Just (t, m)) _) -> Just . not . null $ runList [] t [f]
+        (ParseResult (Just (t, m)) _) -> Just . not . null $ runList defaultAnalysisOptions t [f]
         _ -> Nothing
 
 
@@ -504,7 +496,7 @@ checkPipePitfalls _ (T_Pipeline id _ commands) = do
         \(find:xargs:_) ->
           let args = deadSimple xargs ++ deadSimple find
           in
-            unless (or $ map ($ args) [
+            unless (any ($ args) [
                 hasShortParameter '0',
                 hasParameter "null",
                 hasParameter "print0",
@@ -541,9 +533,9 @@ checkPipePitfalls _ (T_Pipeline id _ commands) = do
     for' l f = for l (first f)
     first func (x:_) = func (getId x)
     first _ _ = return ()
-    hasShortParameter char list = any (\x -> "-" `isPrefixOf` x && char `elem` x) list
-    hasParameter string list =
-        any (isPrefixOf string . dropWhile (== '-')) list
+    hasShortParameter char = any (\x -> "-" `isPrefixOf` x && char `elem` x)
+    hasParameter string =
+        any (isPrefixOf string . dropWhile (== '-'))
 checkPipePitfalls _ _ = return ()
 
 indexOfSublists sub = f 0
@@ -593,11 +585,17 @@ mayBecomeMultipleArgs t = willBecomeMultipleArgs t || f t
     f (T_NormalWord _ parts) = any f parts
     f _ = False
 
-prop_checkShebang1 = verifyTree checkShebang "#!/usr/bin/env bash -x\necho cow"
-prop_checkShebang2 = verifyNotTree checkShebang "#! /bin/sh  -l "
-checkShebang _ (T_Script id sb _) =
+prop_checkShebangParameters1 = verifyTree checkShebangParameters "#!/usr/bin/env bash -x\necho cow"
+prop_checkShebangParameters2 = verifyNotTree checkShebangParameters "#! /bin/sh  -l "
+checkShebangParameters _ (T_Script id sb _) =
     [Note id ErrorC 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"
+checkShebang params (T_Script id sb _) = 
+    [Note id ErrorC 2148 "Include a shebang (#!) to specify the shell." | sb == ""]
+
 prop_checkBashisms = verify checkBashisms "while read a; do :; done < <(a)"
 prop_checkBashisms2 = verify checkBashisms "[ foo -nt bar ]"
 prop_checkBashisms3 = verify checkBashisms "echo $((i++))"
@@ -618,8 +616,8 @@ prop_checkBashisms17= verify checkBashisms "echo $((RANDOM%6+1))"
 prop_checkBashisms18= verify checkBashisms "foo &> /dev/null"
 checkBashisms _ = bashism
   where
-    errMsg id s = err id 2040 $ "#!/bin/sh was specified, so " ++ s ++ " not supported, even when sh is actually bash."
-    warnMsg id s = warn id 2039 $ "#!/bin/sh was specified, but " ++ s ++ " not standard."
+    errMsg id s = err id 2040 $ "In sh, " ++ s ++ " not supported, even when sh is actually bash."
+    warnMsg id s = warn id 2039 $ "In POSIX sh, " ++ s ++ " not supported."
     bashism (T_ProcSub id _ _) = errMsg id "process substitution is"
     bashism (T_Extglob id _ _) = warnMsg id "extglob is"
     bashism (T_DollarSingleQuoted id _) = warnMsg id "$'..' is"
@@ -1412,7 +1410,7 @@ getWordParts (T_NormalWord _ l)   = concatMap getWordParts l
 getWordParts (T_DoubleQuoted _ l) = l
 getWordParts other                = [other]
 
-isCommand token str = isCommandMatch token (\cmd -> cmd  == str || ("/" ++ str) `isSuffixOf` cmd)
+isCommand token str = isCommandMatch token (\cmd -> cmd  == str || ('/' : str) `isSuffixOf` cmd)
 isUnqualifiedCommand token str = isCommandMatch token (== str)
 
 isCommandMatch token matcher = fromMaybe False $ do

ShellCheck/Options.hs

+module ShellCheck.Options where
+
+data Shell = Ksh | Zsh | Sh | Bash
+    deriving (Show, Eq)
+
+data AnalysisOptions = AnalysisOptions {
+    optionShellType :: Maybe Shell,
+    optionExcludes :: [Integer]
+}
+
+defaultAnalysisOptions = AnalysisOptions {
+    optionShellType = Nothing,
+    optionExcludes = []
+}

ShellCheck/Parser.hs

@@ -1801,8 +1801,7 @@ readLetSuffix = many1 (readIoRedirect <|> try readLetExpression <|> readCmdWord)
 -- Get whatever a parser would parse as a string
 readStringForParser parser = do
     pos <- lookAhead (parser >> getPosition)
-    s <- readUntil pos
-    return s
+    readUntil pos
   where
     readUntil endPos = anyChar `reluctantlyTill` (getPosition >>= guard . (== endPos))
 
@@ -1995,11 +1994,11 @@ readScript = do
             return $ T_Script id sb commands;
         } <|> do {
             parseProblem WarningC 1014 "Couldn't read any commands.";
-            return $ T_Script id sb [T_EOF id];
+            return $ T_Script id sb []
         }
       else do
         many anyChar
-        return $ T_Script id sb [T_EOF id];
+        return $ T_Script id sb [];
 
   where
     basename s = reverse . takeWhile (/= '/') . reverse $ s

ShellCheck/Simple.hs

@@ -18,15 +18,16 @@
 {-# LANGUAGE TemplateHaskell #-}
 module ShellCheck.Simple (shellCheck, ShellCheckComment, scLine, scColumn, scSeverity, scCode, scMessage, runTests) where
 
-import ShellCheck.Parser hiding (runTests)
-import ShellCheck.Analytics hiding (runTests)
-import Data.Maybe
-import Text.Parsec.Pos
 import Data.List
+import Data.Maybe
+import ShellCheck.Analytics hiding (runTests)
+import ShellCheck.Options
+import ShellCheck.Parser hiding (runTests)
 import Test.QuickCheck.All (quickCheckAll)
+import Text.Parsec.Pos
 
-shellCheck :: String -> [AnalysisOption] -> [ShellCheckComment]
-shellCheck script options =
+shellCheck :: AnalysisOptions -> String -> [ShellCheckComment]
+shellCheck options script =
     let (ParseResult result notes) = parseShell "-" script in
         let allNotes = notes ++ concat (maybeToList $ do
             (tree, posMap) <- result
@@ -51,21 +52,25 @@ severityToString s =
 formatNote (ParseNote pos severity code text) =
     ShellCheckComment (sourceLine pos) (sourceColumn pos) (severityToString severity) (fromIntegral code) text
 
+testCheck = shellCheck defaultAnalysisOptions { optionExcludes = [2148] } -- Ignore #! warnings
 prop_findsParseIssue =
-    let comments = shellCheck "echo \"$12\"" [] in
+    let comments = testCheck "echo \"$12\"" in
         length comments == 1 && scCode (head comments) == 1037
 prop_commentDisablesParseIssue1 =
-    null $ shellCheck "#shellcheck disable=SC1037\necho \"$12\"" []
+    null $ testCheck "#shellcheck disable=SC1037\necho \"$12\""
 prop_commentDisablesParseIssue2 =
-    null $ shellCheck "#shellcheck disable=SC1037\n#lol\necho \"$12\"" []
+    null $ testCheck "#shellcheck disable=SC1037\n#lol\necho \"$12\""
 
 prop_findsAnalysisIssue =
-    let comments = shellCheck "echo $1" [] in
+    let comments = testCheck "echo $1" in
         length comments == 1 && scCode (head comments) == 2086
 prop_commentDisablesAnalysisIssue1 =
-    null $ shellCheck "#shellcheck disable=SC2086\necho $1" []
+    null $ testCheck "#shellcheck disable=SC2086\necho $1"
 prop_commentDisablesAnalysisIssue2 =
-    null $ shellCheck "#shellcheck disable=SC2086\n#lol\necho $1" []
+    null $ testCheck "#shellcheck disable=SC2086\n#lol\necho $1"
+
+prop_optionDisablesIssue1 =
+    null $ shellCheck (defaultAnalysisOptions { optionExcludes = [2086, 2148] }) "echo $1"
 
 return []
 runTests = $quickCheckAll

shellcheck.1.md

@@ -18,24 +18,28 @@ corner cases can cause delayed failures.
 
 # OPTIONS
 
-**-f** *FORMAT*, **--format=***FORMAT*
-
-:   Specify the output format of shellcheck, which prints its results in the
-    standard output. Subsequent **-f** options are ignored, see **FORMATS**
-    below for more information.
-
 **-e**\ *CODE1*[,*CODE2*...],\ **--exclude=***CODE1*[,*CODE2*...]
 
 :   Explicitly exclude the specified codes from the report. Subsequent **-e**
     options are cumulative, but all the codes can be specified at once,
     comma-separated as a single argument.
 
+**-f** *FORMAT*, **--format=***FORMAT*
+
+:   Specify the output format of shellcheck, which prints its results in the
+    standard output. Subsequent **-f** options are ignored, see **FORMATS**
+    below for more information.
+
 **-s**\ *shell*,\ **--shell=***shell*
 
 :   Specify Bourne shell dialect. Valid values are *sh*, *bash*, *ksh* and
     *zsh*. The default is to use the file's shebang, or *bash* if the target
     shell can't be determined.
 
+**-V**\ *version*,\ **--version**
+
+:   Print version and exit.
+
 # FORMATS
 
 **tty**

shellcheck.hs

@@ -26,6 +26,7 @@ import GHC.Exts
 import GHC.IO.Device
 import Prelude hiding (catch)
 import ShellCheck.Data
+import ShellCheck.Options
 import ShellCheck.Simple
 import ShellCheck.Analytics
 import System.Console.GetOpt
@@ -48,10 +49,10 @@ instance Monoid Status where
 
 header = "Usage: shellcheck [OPTIONS...] FILES..."
 options = [
-    Option "f" ["format"]
-        (ReqArg (Flag "format") "FORMAT") "output format",
     Option "e" ["exclude"]
         (ReqArg (Flag "exclude") "CODE1,CODE2..") "exclude types of warnings",
+    Option "f" ["format"]
+        (ReqArg (Flag "format") "FORMAT") "output format",
     Option "s" ["shell"]
         (ReqArg (Flag "shell") "SHELLNAME") "Specify dialect (bash,sh,ksh,zsh)",
     Option "V" ["version"]
@@ -74,15 +75,12 @@ instance JSON ShellCheckComment where
 parseArguments :: [String] -> ErrorT Status IO ([Flag], [FilePath])
 parseArguments argv =
     case getOpt Permute options argv of
-        (opts, files, []) -> do
-            verifyOptions opts files
-            return (opts, files)
-
+        (opts, files, []) -> return (opts, files)
         (_, _, errors) -> do
             liftIO . printErr $ concat errors ++ "\n" ++ usageInfo header options
             throwError SyntaxFailure
 
-formats :: Map.Map String ([Flag] -> [FilePath] -> IO Status)
+formats :: Map.Map String (AnalysisOptions -> [FilePath] -> IO Status)
 formats = Map.fromList [
     ("json", forJson),
     ("gcc", forGcc),
@@ -93,7 +91,7 @@ formats = Map.fromList [
 toStatus = liftM (either id (const NoProblems)) . runErrorT
 
 catchExceptions :: IO Status -> IO Status
-catchExceptions action = action `catch` handler
+catchExceptions action = action -- action `catch` handler
   where
     handler err = do
         printErr $ show (err :: SomeException)
@@ -101,7 +99,7 @@ catchExceptions action = action `catch` handler
 
 checkComments comments = if null comments then NoProblems else SomeProblems
 
-forTty :: [Flag] -> [FilePath] -> IO Status
+forTty :: AnalysisOptions -> [FilePath] -> IO Status
 forTty options files = do
     output <- mapM doFile files
     return $ mconcat output
@@ -155,14 +153,14 @@ forTty options files = do
         return $ if term then colorComment else const id
 
 -- This totally ignores the filenames. Fixme?
-forJson :: [Flag] -> [FilePath] -> IO Status
+forJson :: AnalysisOptions -> [FilePath] -> IO Status
 forJson options files = catchExceptions $ do
     comments <- liftM concat $ mapM (commentsFor options) files
     putStrLn $ encodeStrict comments
     return $ checkComments comments
 
 -- Mimic GCC "file:line:col: (error|warning|note): message" format
-forGcc :: [Flag] -> [FilePath] -> IO Status
+forGcc :: AnalysisOptions -> [FilePath] -> IO Status
 forGcc options files = do
     files <- mapM process files
     return $ mconcat files
@@ -187,7 +185,7 @@ forGcc options files = do
       ]
 
 -- Checkstyle compatible output. A bit of a hack to avoid XML dependencies
-forCheckstyle :: [Flag] -> [FilePath] -> IO Status
+forCheckstyle :: AnalysisOptions -> [FilePath] -> IO Status
 forCheckstyle options files = do
     putStrLn "<?xml version='1.0' encoding='UTF-8'?>"
     putStrLn "<checkstyle version='4.3'>"
@@ -226,23 +224,13 @@ forCheckstyle options files = do
 
 commentsFor options file = liftM (getComments options) $ readContents file
 
-getComments options contents =
-    excludeCodes (getExclusions options) $ shellCheck contents analysisOptions
-  where
-    analysisOptions = catMaybes [ shellOption ]
-    shellOption = do
-        option <- getOption options "shell"
-        sh <- shellForExecutable option
-        return $ ForceShell sh
-
+getComments = shellCheck
 
 readContents :: FilePath -> IO String
 readContents file =
     if file == "-"
     then getContents
     else readFile file
-  where
-    force s = foldr (flip const) s s
 
 -- Realign comments from a tabstop of 8 to 1
 makeNonVirtual comments contents =
@@ -300,8 +288,10 @@ statusToCode status =
         RuntimeException -> ExitFailure 2
 
 process :: [Flag] -> [FilePath] -> ErrorT Status IO ()
-process options files =
-  let format = fromMaybe "tty" $ getOption options "format" in
+process flags files = do
+    options <- foldM (flip parseOption) defaultAnalysisOptions flags
+    verifyFiles files
+    let format = fromMaybe "tty" $ getOption flags "format"
     case Map.lookup format formats of
         Nothing -> do
             liftIO $ do
@@ -312,17 +302,35 @@ process options files =
           where write s = "  " ++ s
         Just f -> ErrorT $ liftM Left $ f options files
 
-verifyOptions :: [Flag] -> [FilePath] -> ErrorT Status IO ()
-verifyOptions opts files = do
-    when (isJust $ getOption opts "version") $ do
-        liftIO printVersion
-        throwError NoProblems
+parseOption flag options =
+    case flag of
+        Flag "shell" str ->
+                fromMaybe (die $ "Unknown shell: " ++ str) $ do
+                    shell <- shellForExecutable str
+                    return $ return options { optionShellType = Just shell }
 
-    let shell = getOption opts "shell" in
-        when (isJust shell && isNothing (shell >>= shellForExecutable)) $ do
-            liftIO $ printErr ("Unknown shell: " ++ fromJust shell)
-            throwError SupportFailure
+        Flag "exclude" str -> do
+            new <- mapM parseNum $ split ',' str
+            let old = optionExcludes options
+            return options { optionExcludes = new ++ old }
+
+        Flag "version" _ -> do
+            liftIO printVersion
+            throwError NoProblems
+
+        _ -> return options
+  where
+    die s = do
+        liftIO $ printErr s
+        throwError SupportFailure
+    parseNum ('S':'C':str) = parseNum str
+    parseNum num = do
+        unless (all isDigit num) $ do
+            liftIO . printErr $ "Bad exclusion: " ++ num
+            throwError SyntaxFailure
+        return (Prelude.read num :: Integer)
 
+verifyFiles files =
     when (null files) $ do
         liftIO $ printErr "No files specified.\n"
         liftIO $ printErr $ usageInfo header options