Improve Fix memory usage

ShellCheck.cabal

@@ -53,6 +53,7 @@ library
       base > 4.6.0.1 && < 5,
       bytestring,
       containers >= 0.5,
+      deepseq >= 1.4.0.0,
       directory,
       mtl >= 2.2.1,
       parsec,
@@ -89,6 +90,7 @@ executable shellcheck
       aeson,
       base >= 4 && < 5,
       bytestring,
+      deepseq >= 1.4.0.0,
       ShellCheck,
       containers,
       directory,
@@ -104,6 +106,7 @@ test-suite test-shellcheck
       aeson,
       base >= 4 && < 5,
       bytestring,
+      deepseq >= 1.4.0.0,
       ShellCheck,
       containers,
       directory,

src/ShellCheck/AST.hs

@@ -17,14 +17,17 @@
     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 DeriveGeneric, DeriveAnyClass #-}
 module ShellCheck.AST where
 
+import GHC.Generics (Generic)
 import Control.Monad.Identity
+import Control.DeepSeq
 import Text.Parsec
 import qualified ShellCheck.Regex as Re
 import Prelude hiding (id)
 
-newtype Id = Id Int deriving (Show, Eq, Ord)
+newtype Id = Id Int deriving (Show, Eq, Ord, Generic, NFData)
 
 data Quoted = Quoted | Unquoted deriving (Show, Eq)
 data Dashed = Dashed | Undashed deriving (Show, Eq)

src/ShellCheck/Analytics.hs

@@ -241,6 +241,39 @@ isCondition (child:parent:rest) =
             T_UntilExpression id c l -> take 1 . reverse $ c
             _ -> []
 
+-- helpers to build replacements
+replaceStart id params n r =
+    let tp = tokenPositions params
+        (start, _) = tp Map.! id
+        new_end = start {
+            posColumn = posColumn start + n
+        }
+    in
+    newReplacement {
+        repStartPos = start,
+        repEndPos = new_end,
+        repString = r
+    }
+replaceEnd id params n r =
+    -- because of the way we count columns 1-based
+    -- we have to offset end columns by 1
+    let tp = tokenPositions params
+        (_, end) = tp Map.! id
+        new_start = end {
+            posColumn = posColumn end - n + 1
+        }
+        new_end = end {
+            posColumn = posColumn end + 1
+        }
+    in
+    newReplacement {
+        repStartPos = new_start,
+        repEndPos = new_end,
+        repString = r
+    }
+surroundWidth id params s = fixWith [replaceStart id params 0 s, replaceEnd id params 0 s]
+fixWith fixes = newFix { fixReplacements = fixes }
+
 prop_checkEchoWc3 = verify checkEchoWc "n=$(echo $foo | wc -c)"
 checkEchoWc _ (T_Pipeline id _ [a, b]) =
     when (acmd == ["echo", "${VAR}"]) $
@@ -1334,8 +1367,10 @@ 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 $(...) notation instead of legacy backticked `...`."
+checkBackticks params (T_Backticked id list) | not (null list) =
+    addComment $
+        makeCommentWithFix StyleC id 2006  "Use $(...) notation instead of legacy backticked `...`."
+            (fixWith [replaceStart id params 1 "$(", replaceEnd id params 1 ")"])
 checkBackticks _ _ = return ()
 
 prop_checkIndirectExpansion1 = verify checkIndirectExpansion "${foo$n}"
@@ -1639,8 +1674,10 @@ checkSpacefulness params t =
                 makeComment InfoC (getId token) 2223
                     "This default assignment may cause DoS due to globbing. Quote it."
             else
-                makeComment InfoC (getId token) 2086
-                    "Double quote to prevent globbing and word splitting."
+                makeCommentWithFix InfoC (getId token) 2086
+                    "Double quote to prevent globbing and word splitting." (surroundWidth (getId token) params "\"")
+                -- makeComment InfoC (getId token) 2086
+                --     "Double quote to prevent globbing and word splitting."
 
     writeF _ _ name (DataString SourceExternal) = setSpaces name True >> return []
     writeF _ _ name (DataString SourceInteger) = setSpaces name False >> return []
@@ -2537,7 +2574,8 @@ checkUncheckedCdPushdPopd params root =
             && not (isSafeDir t)
             && not (name t `elem` ["pushd", "popd"] && ("n" `elem` map snd (getAllFlags t)))
             && not (isCondition $ getPath (parentMap params) t)) $
-                warn (getId t) 2164 "Use 'cd ... || exit' or 'cd ... || return' in case cd fails."
+                warnWithFix (getId t) 2164 "Use 'cd ... || exit' or 'cd ... || return' in case cd fails."
+                    (fixWith [replaceEnd (getId t) params 0 " || exit"])
     checkElement _ = return ()
     name t = fromMaybe "" $ getCommandName t
     isSafeDir t = case oversimplify t of
@@ -2694,7 +2732,7 @@ checkArrayAssignmentIndices params root =
                         T_Literal id str -> [(id,str)]
                         _ -> []
                     guard $ '=' `elem` str
-                    return $ warn id 2191 "The = here is literal. To assign by index, use ( [index]=value ) with no spaces. To keep as literal, quote it."
+                    return $ warnWithFix id 2191 "The = here is literal. To assign by index, use ( [index]=value ) with no spaces. To keep as literal, quote it." (surroundWidth id params "\"")
                 in
                     if null literalEquals && isAssociative
                     then warn (getId t) 2190 "Elements in associative arrays need index, e.g. array=( [index]=value ) ."

src/ShellCheck/AnalyzerLib.hs

@@ -20,6 +20,7 @@
 {-# LANGUAGE FlexibleContexts #-}
 {-# LANGUAGE TemplateHaskell  #-}
 module ShellCheck.AnalyzerLib where
+
 import ShellCheck.AST
 import ShellCheck.ASTLib
 import ShellCheck.Data
@@ -28,15 +29,16 @@ import           ShellCheck.Parser
 import ShellCheck.Regex
 
 import Control.Arrow (first)
+import Control.DeepSeq
 import Control.Monad.Identity
 import Control.Monad.RWS
 import Control.Monad.State
 import Control.Monad.Writer
 import Data.Char
 import Data.List
-import qualified Data.Map               as Map
 import Data.Maybe
 import Data.Semigroup
+import qualified Data.Map as Map
 
 import Test.QuickCheck.All (forAllProperties)
 import Test.QuickCheck.Test (maxSuccess, quickCheckWithResult, stdArgs)
@@ -81,7 +83,8 @@ data Parameters = Parameters {
     parentMap          :: Map.Map Id Token, -- A map from Id to parent Token
     shellType          :: Shell,            -- The shell type, such as Bash or Ksh
     shellTypeSpecified :: Bool,    -- True if shell type was forced via flags
-    rootNode           :: Token              -- The root node of the AST
+    rootNode           :: Token,              -- The root node of the AST
+    tokenPositions     :: Map.Map Id (Position, Position) -- map from token id to start and end position
     }
 
 -- TODO: Cache results of common AST ops here
@@ -142,7 +145,7 @@ makeComment severity id code note =
         }
     }
 
-addComment note = tell [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
@@ -150,6 +153,20 @@ 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
 
+warnWithFix id code str fix = addComment $
+    let comment = makeComment WarningC id code str in
+    comment {
+        tcFix = Just fix
+    }
+
+makeCommentWithFix :: Severity -> Id -> Code -> String -> Fix -> TokenComment
+makeCommentWithFix severity id code str fix =
+    let comment = makeComment severity id code str
+        withFix = comment {
+            tcFix = Just fix
+        }
+    in withFix `deepseq` withFix
+
 makeParameters spec =
     let params = Parameters {
         rootNode = root,
@@ -164,7 +181,8 @@ makeParameters spec =
 
         shellTypeSpecified = isJust $ asShellType spec,
         parentMap = getParentTree root,
-        variableFlow = getVariableFlow params root
+        variableFlow = getVariableFlow params root,
+        tokenPositions = asTokenPositions spec
     } in params
   where root = asScript spec
 

src/ShellCheck/Checker.hs

@@ -42,7 +42,8 @@ tokenToPosition startMap t = fromMaybe fail $ do
     return $ newPositionedComment {
         pcStartPos = fst span,
         pcEndPos = snd span,
-        pcComment = tcComment t
+        pcComment = tcComment t,
+        pcFix = tcFix t
     }
   where
     fail = error "Internal shellcheck error: id doesn't exist. Please report!"
@@ -63,11 +64,20 @@ checkScript sys spec = do
             psShellTypeOverride = csShellTypeOverride spec
         }
         let parseMessages = prComments result
+        let tokenPositions = prTokenPositions result
+        let analysisSpec root =
+                as {
+                    asScript = root,
+                    asShellType = csShellTypeOverride spec,
+                    asCheckSourced = csCheckSourced spec,
+                    asExecutionMode = Executed,
+                    asTokenPositions = tokenPositions
+                } where as = newAnalysisSpec root
         let analysisMessages =
                 fromMaybe [] $
                     (arComments . analyzeScript . analysisSpec)
                         <$> prRoot result
-        let translator = tokenToPosition (prTokenPositions result)
+        let translator = tokenToPosition tokenPositions
         return . nub . sortMessages . filter shouldInclude $
             (parseMessages ++ map translator analysisMessages)
 
@@ -90,13 +100,6 @@ checkScript sys spec = do
          cMessage comment)
     getPosition = pcStartPos
 
-    analysisSpec root =
-        as {
-            asScript = root,
-            asShellType = csShellTypeOverride spec,
-            asCheckSourced = csCheckSourced spec,
-            asExecutionMode = Executed
-         } where as = newAnalysisSpec root
 
 getErrors sys spec =
     sort . map getCode . crComments $

src/ShellCheck/Formatter/JSON.hs

@@ -39,7 +39,20 @@ format = do
         footer = finish ref
     }
 
-instance ToJSON (PositionedComment) where
+instance ToJSON Replacement where
+    toJSON replacement =
+        let start = repStartPos replacement
+            end = repEndPos replacement
+            str = repString replacement in
+        object [
+          "line" .= posLine start,
+          "endLine" .= posLine end,
+          "column" .= posColumn start,
+          "endColumn" .= posColumn end,
+          "replaceWith" .= str
+        ]
+
+instance ToJSON PositionedComment where
   toJSON comment =
     let start = pcStartPos comment
         end = pcEndPos comment
@@ -52,7 +65,8 @@ instance ToJSON (PositionedComment) where
       "endColumn" .= posColumn end,
       "level" .= severityText comment,
       "code" .= cCode c,
-      "message" .= cMessage c
+      "message" .= cMessage c,
+      "fix" .= pcFix comment
     ]
 
   toEncoding comment =
@@ -68,8 +82,14 @@ instance ToJSON (PositionedComment) where
       <> "level" .= severityText comment
       <> "code" .= cCode c
       <> "message" .= cMessage c
+      <> "fix" .= pcFix comment
     )
 
+instance ToJSON Fix where
+    toJSON fix = object [
+        "replacements" .= fixReplacements fix
+        ]
+
 outputError file msg = hPutStrLn stderr $ file ++ ": " ++ msg
 collectResult ref result _ =
     modifyIORef ref (\x -> crComments result ++ x)
@@ -77,4 +97,3 @@ collectResult ref result _ =
 finish ref = do
     list <- readIORef ref
     BL.putStrLn $ encode list
-

src/ShellCheck/Formatter/TTY.hs

@@ -25,6 +25,7 @@ import ShellCheck.Formatter.Format
 import Control.Monad
 import Data.IORef
 import Data.List
+import Data.Maybe
 import GHC.Exts
 import System.IO
 import System.Info
@@ -118,8 +119,8 @@ outputForFile color sys comments = do
     let fileLines = lines contents
     let lineCount = fromIntegral $ length fileLines
     let groups = groupWith lineNo comments
-    mapM_ (\x -> do
-        let lineNum = lineNo (head x)
+    mapM_ (\commentsForLine -> do
+        let lineNum = lineNo (head commentsForLine)
         let line = if lineNum < 1 || lineNum > lineCount
                         then ""
                         else fileLines !! fromIntegral (lineNum - 1)
@@ -127,10 +128,62 @@ outputForFile color sys comments = do
         putStrLn $ color "message" $
            "In " ++ fileName ++" line " ++ show lineNum ++ ":"
         putStrLn (color "source" line)
-        mapM_ (\c -> putStrLn (color (severityText c) $ cuteIndent c)) x
+        mapM_ (\c -> putStrLn (color (severityText c) $ cuteIndent c)) commentsForLine
         putStrLn ""
+        -- FIXME: Enable when reasonably stable
+        -- showFixedString color comments lineNum line
       ) groups
 
+hasApplicableFix lineNum comment = fromMaybe False $ do
+    replacements <- fixReplacements <$> pcFix comment
+    guard $ all (\c -> onSameLine (repStartPos c) && onSameLine (repEndPos c)) replacements
+    return True
+  where
+    onSameLine pos = posLine pos == lineNum
+
+-- FIXME: Work correctly with multiple replacements
+showFixedString color comments lineNum line =
+    case filter (hasApplicableFix lineNum) comments of
+        (first:_) -> do
+            -- in the spirit of error prone
+            putStrLn $ color "message" "Did you mean: "
+            putStrLn $ fixedString first line
+            putStrLn ""
+        _ -> return ()
+
+-- need to do something smart about sorting by end index
+fixedString :: PositionedComment -> String -> String
+fixedString comment line =
+    case (pcFix comment) of
+    Nothing -> ""
+    Just rs ->
+        applyReplacement (fixReplacements rs) line 0
+        where
+            applyReplacement [] s _ = s
+            applyReplacement (rep:xs) s offset =
+                let replacementString = repString rep
+                    start = (posColumn . repStartPos) rep
+                    end = (posColumn . repEndPos) rep
+                    z = doReplace start end s replacementString
+                    len_r = (fromIntegral . length) replacementString in
+                applyReplacement xs z (offset + (end - start) + len_r)
+
+-- FIXME: Work correctly with tabs
+-- start and end comes from pos, which is 1 based
+-- doReplace 0 0 "1234" "A" -> "A1234" -- technically not valid
+-- doReplace 1 1 "1234" "A" -> "A1234"
+-- doReplace 1 2 "1234" "A" -> "A234"
+-- doReplace 3 3 "1234" "A" -> "12A34"
+-- doReplace 4 4 "1234" "A" -> "123A4"
+-- doReplace 5 5 "1234" "A" -> "1234A"
+doReplace start end o r =
+    let si = fromIntegral (start-1)
+        ei = fromIntegral (end-1)
+        (x, xs) = splitAt si o
+        (y, z) = splitAt (ei - si) xs
+    in
+    x ++ r ++ z
+
 cuteIndent :: PositionedComment -> String
 cuteIndent comment =
     replicate (fromIntegral $ colNo comment - 1) ' ' ++

src/ShellCheck/Interface.hs

@@ -17,6 +17,7 @@
     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 DeriveGeneric, DeriveAnyClass #-}
 module ShellCheck.Interface
     (
     SystemInterface(..)
@@ -24,7 +25,7 @@ module ShellCheck.Interface
     , CheckResult(crFilename, crComments)
     , ParseSpec(psFilename, psScript, psCheckSourced, psShellTypeOverride)
     , ParseResult(prComments, prTokenPositions, prRoot)
-    , AnalysisSpec(asScript, asShellType, asExecutionMode, asCheckSourced)
+    , AnalysisSpec(asScript, asShellType, asExecutionMode, asCheckSourced, asTokenPositions)
     , AnalysisResult(arComments)
     , FormatterOptions(foColorOption, foWikiLinkCount)
     , Shell(Ksh, Sh, Bash, Dash)
@@ -34,9 +35,9 @@ module ShellCheck.Interface
     , Severity(ErrorC, WarningC, InfoC, StyleC)
     , Position(posFile, posLine, posColumn)
     , Comment(cSeverity, cCode, cMessage)
-    , PositionedComment(pcStartPos , pcEndPos , pcComment)
+    , PositionedComment(pcStartPos , pcEndPos , pcComment, pcFix)
     , ColorOption(ColorAuto, ColorAlways, ColorNever)
-    , TokenComment(tcId, tcComment)
+    , TokenComment(tcId, tcComment, tcFix)
     , emptyCheckResult
     , newParseResult
     , newAnalysisSpec
@@ -49,10 +50,18 @@ module ShellCheck.Interface
     , emptyCheckSpec
     , newPositionedComment
     , newComment
+    , Fix(fixReplacements)
+    , newFix
+    , Replacement(repStartPos, repEndPos, repString)
+    , newReplacement
     ) where
 
 import ShellCheck.AST
+
+import Control.DeepSeq
 import Control.Monad.Identity
+import Data.Monoid
+import GHC.Generics (Generic)
 import qualified Data.Map as Map
 
 
@@ -126,14 +135,16 @@ data AnalysisSpec = AnalysisSpec {
     asScript :: Token,
     asShellType :: Maybe Shell,
     asExecutionMode :: ExecutionMode,
-    asCheckSourced :: Bool
+    asCheckSourced :: Bool,
+    asTokenPositions :: Map.Map Id (Position, Position)
 }
 
 newAnalysisSpec token = AnalysisSpec {
     asScript = token,
     asShellType = Nothing,
     asExecutionMode = Executed,
-    asCheckSourced = False
+    asCheckSourced = False,
+    asTokenPositions = Map.empty
 }
 
 newtype AnalysisResult = AnalysisResult {
@@ -163,12 +174,13 @@ data ExecutionMode = Executed | Sourced deriving (Show, Eq)
 type ErrorMessage = String
 type Code = Integer
 
-data Severity = ErrorC | WarningC | InfoC | StyleC deriving (Show, Eq, Ord)
+data Severity = ErrorC | WarningC | InfoC | StyleC
+    deriving (Show, Eq, Ord, Generic, NFData)
 data Position = Position {
     posFile :: String,    -- Filename
     posLine :: Integer,   -- 1 based source line
     posColumn :: Integer  -- 1 based source column, where tabs are 8
-} deriving (Show, Eq)
+} deriving (Show, Eq, Generic, NFData)
 
 newPosition :: Position
 newPosition = Position {
@@ -181,7 +193,7 @@ data Comment = Comment {
     cSeverity :: Severity,
     cCode     :: Code,
     cMessage  :: String
-} deriving (Show, Eq)
+} deriving (Show, Eq, Generic, NFData)
 
 newComment :: Comment
 newComment = Comment {
@@ -190,27 +202,52 @@ newComment = Comment {
     cMessage  = ""
 }
 
+-- only support single line for now
+data Replacement = Replacement {
+    repStartPos :: Position,
+    repEndPos :: Position,
+    repString :: String
+} deriving (Show, Eq, Generic, NFData)
+
+newReplacement = Replacement {
+    repStartPos = newPosition,
+    repEndPos = newPosition,
+    repString = ""
+}
+
+data Fix = Fix {
+    fixReplacements :: [Replacement]
+} deriving (Show, Eq, Generic, NFData)
+
+newFix = Fix {
+    fixReplacements = []
+}
+
 data PositionedComment = PositionedComment {
     pcStartPos :: Position,
     pcEndPos   :: Position,
-    pcComment  :: Comment
-} deriving (Show, Eq)
+    pcComment  :: Comment,
+    pcFix      :: Maybe Fix
+} deriving (Show, Eq, Generic, NFData)
 
 newPositionedComment :: PositionedComment
 newPositionedComment = PositionedComment {
     pcStartPos = newPosition,
     pcEndPos   = newPosition,
-    pcComment  = newComment
+    pcComment  = newComment,
+    pcFix      = Nothing
 }
 
 data TokenComment = TokenComment {
     tcId :: Id,
-    tcComment :: Comment
-} deriving (Show, Eq)
+    tcComment :: Comment,
+    tcFix :: Maybe Fix
+} deriving (Show, Eq, Generic, NFData)
 
 newTokenComment = TokenComment {
     tcId = Id 0,
-    tcComment = newComment
+    tcComment = newComment,
+    tcFix = Nothing
 }
 
 data ColorOption =