Main.hs

{-# OPTIONS_GHC -Wno-orphans #-}
module Development.IDE.Main
(Arguments(..)
,defaultArguments
,Command(..)
,IdeCommand(..)
,isLSP
,commandP
,defaultMain
,testing
,Log(..)
) where

import           Control.Concurrent.Extra                 (withNumCapabilities)
import           Control.Concurrent.MVar                  (MVar, newEmptyMVar,
                                                           putMVar, tryReadMVar)
import           Control.Concurrent.STM.Stats             (dumpSTMStats)
import           Control.Exception.Safe                   as Safe
import           Control.Monad.Extra                      (concatMapM, unless,
                                                           when)
import           Control.Monad.IO.Class                   (liftIO)
import qualified Data.Aeson                               as J
import           Data.Coerce                              (coerce)
import           Data.Default                             (Default (def))
import           Data.Hashable                            (hashed)
import qualified Data.HashMap.Strict                      as HashMap
import           Data.List.Extra                          (intercalate,
                                                           isPrefixOf, nubOrd,
                                                           partition)
import           Data.Maybe                               (catMaybes, isJust)
import qualified Data.Text                                as T
import           Development.IDE                          (Action,
                                                           Priority (Debug),
                                                           Rules, hDuplicateTo')
import           Development.IDE.Core.Debouncer           (Debouncer,
                                                           newAsyncDebouncer)
import           Development.IDE.Core.FileStore           (isWatchSupported,
                                                           setSomethingModified)
import           Development.IDE.Core.IdeConfiguration    (IdeConfiguration (..),
                                                           modifyClientSettings,
                                                           registerIdeConfiguration)
import           Development.IDE.Core.OfInterest          (FileOfInterestStatus (OnDisk),
                                                           kick,
                                                           setFilesOfInterest)
import           Development.IDE.Core.Rules               (mainRule)
import qualified Development.IDE.Core.Rules               as Rules
import           Development.IDE.Core.RuleTypes           (GenerateCore (GenerateCore),
                                                           GetHieAst (GetHieAst),
                                                           TypeCheck (TypeCheck))
import           Development.IDE.Core.Service             (initialise,
                                                           runAction)
import qualified Development.IDE.Core.Service             as Service
import           Development.IDE.Core.Shake               (IdeState (shakeExtras),
                                                           ThreadQueue (tLoaderQueue),
                                                           shakeSessionInit,
                                                           uses)
import qualified Development.IDE.Core.Shake               as Shake
import           Development.IDE.Graph                    (action)
import           Development.IDE.LSP.LanguageServer       (runLanguageServer,
                                                           runWithWorkerThreads,
                                                           setupLSP)
import qualified Development.IDE.LSP.LanguageServer       as LanguageServer
import           Development.IDE.Main.HeapStats           (withHeapStats)
import qualified Development.IDE.Main.HeapStats           as HeapStats
import qualified Development.IDE.Monitoring.OpenTelemetry as OpenTelemetry
import           Development.IDE.Plugin                   (Plugin (pluginHandlers, pluginModifyDynflags, pluginRules))
import           Development.IDE.Plugin.HLS               (asGhcIdePlugin)
import qualified Development.IDE.Plugin.HLS               as PluginHLS
import qualified Development.IDE.Plugin.HLS.GhcIde        as GhcIde
import qualified Development.IDE.Plugin.Test              as Test
import           Development.IDE.Session                  (SessionLoadingOptions,
                                                           getHieDbLoc,
                                                           getInitialGhcLibDirDefault,
                                                           loadSessionWithOptions,
                                                           retryOnSqliteBusy)
import qualified Development.IDE.Session                  as Session
import           Development.IDE.Types.Location           (NormalizedUri,
                                                           toNormalizedFilePath')
import           Development.IDE.Types.Monitoring         (Monitoring)
import           Development.IDE.Types.Options            (IdeGhcSession,
                                                           IdeOptions (optCheckParents, optCheckProject, optReportProgress, optRunSubset),
                                                           IdeTesting (IdeTesting),
                                                           clientSupportsProgress,
                                                           defaultIdeOptions,
                                                           optModifyDynFlags,
                                                           optTesting)
import           Development.IDE.Types.Shake              (WithHieDb,
                                                           toNoFileKey)
import           GHC.Conc                                 (getNumProcessors)
import           GHC.IO.Encoding                          (setLocaleEncoding)
import           GHC.IO.Handle                            (hDuplicate)
import           HIE.Bios.Cradle                          (findCradle)
import qualified HieDb.Run                                as HieDb
import           Ide.Logger                               (Pretty (pretty),
                                                           Priority (Info),
                                                           Recorder,
                                                           WithPriority,
                                                           cmapWithPrio,
                                                           logWith, nest, vsep,
                                                           (<+>))
import           Ide.Plugin.Config                        (CheckParents (NeverCheck),
                                                           Config, checkParents,
                                                           checkProject,
                                                           getConfigFromNotification)
import           Ide.PluginUtils                          (allLspCmdIds',
                                                           getProcessID,
                                                           idePluginsToPluginDesc,
                                                           pluginDescToIdePlugins)
import           Ide.Types                                (IdeCommand (IdeCommand),
                                                           IdePlugins,
                                                           PluginDescriptor (PluginDescriptor, pluginCli),
                                                           PluginId (PluginId),
                                                           ipMap, pluginId)
import qualified Language.LSP.Server                      as LSP
import           Numeric.Natural                          (Natural)
import           Options.Applicative                      hiding (action)
import qualified System.Directory.Extra                   as IO
import           System.Exit                              (ExitCode (ExitFailure, ExitSuccess),
                                                           exitWith)
import           System.FilePath                          (takeExtension,
                                                           takeFileName, (</>))
import           System.IO                                (BufferMode (LineBuffering, NoBuffering),
                                                           Handle, hFlush,
                                                           hPutStrLn,
                                                           hSetBuffering,
                                                           hSetEncoding, stderr,
                                                           stdin, stdout, utf8)
import           System.Process                           (readProcessWithExitCode)
import           System.Random                            (newStdGen)
import           System.Time.Extra                        (Seconds, offsetTime,
                                                           showDuration)
import qualified Language.LSP.Protocol.Types as LSP

data Log
  = LogHeapStats !HeapStats.Log
  | LogLspStart [PluginId]
  | LogLspStartDuration !Seconds
  | LogShouldRunSubset !Bool
  | LogConfigurationChange T.Text
  | LogService Service.Log
  | LogShake Shake.Log
  | LogGhcIde GhcIde.Log
  | LogLanguageServer LanguageServer.Log
  | LogSession Session.Log
  | LogPluginHLS PluginHLS.Log
  | LogRules Rules.Log
  | LogUsingGit
  deriving Show

instance Pretty Log where
  pretty = \case
    LogHeapStats msg -> pretty msg
    LogLspStart pluginIds ->
      nest 2 $ vsep
        [ "Starting LSP server..."
        , "If you are seeing this in a terminal, you probably should have run WITHOUT the --lsp option!"
        , "PluginIds:" <+> pretty (coerce @_ @[T.Text] pluginIds)
        ]
    LogLspStartDuration duration ->
      "Started LSP server in" <+> pretty (showDuration duration)
    LogShouldRunSubset shouldRunSubset ->
      "shouldRunSubset:" <+> pretty shouldRunSubset
    LogConfigurationChange msg -> "Configuration changed:" <+> pretty msg
    LogService msg -> pretty msg
    LogShake msg -> pretty msg
    LogGhcIde msg -> pretty msg
    LogLanguageServer msg -> pretty msg
    LogSession msg -> pretty msg
    LogPluginHLS msg -> pretty msg
    LogRules msg -> pretty msg
    LogUsingGit -> "Using git to list file, relying on .gitignore"

data Command
    = Check [FilePath]  -- ^ Typecheck some paths and print diagnostics. Exit code is the number of failures
    | Db {hieOptions ::  HieDb.Options, hieCommand :: HieDb.Command}
     -- ^ Run a command in the hiedb
    | LSP   -- ^ Run the LSP server
    | Custom {ideCommand :: IdeCommand IdeState} -- ^ User defined
    deriving Show

-- TODO move these to hiedb
deriving instance Show HieDb.Command
deriving instance Show HieDb.Options

isLSP :: Command -> Bool
isLSP LSP = True
isLSP _   = False

commandP :: IdePlugins IdeState -> Parser Command
commandP plugins =
    hsubparser(command "typecheck" (info (Check <$> fileCmd) fileInfo)
            <> command "hiedb" (info (Db <$> HieDb.optParser "" True <*> HieDb.cmdParser) hieInfo)
            <> command "lsp" (info (pure LSP) lspInfo)
            <> pluginCommands
            )
  where
    fileCmd = many (argument str (metavar "FILES/DIRS..."))
    lspInfo = fullDesc <> progDesc "Start talking to an LSP client"
    fileInfo = fullDesc <> progDesc "Used as a test bed to check your IDE will work"
    hieInfo = fullDesc <> progDesc "Query .hie files"

    pluginCommands = mconcat
        [ command (T.unpack pId) (Custom <$> p)
        | PluginDescriptor{pluginCli = Just p, pluginId = PluginId pId} <- ipMap plugins
        ]


data Arguments = Arguments
    { argsProjectRoot           :: FilePath
    , argCommand                :: Command
    , argsRules                 :: Rules ()
    , argsHlsPlugins            :: IdePlugins IdeState
    , argsGhcidePlugin          :: Plugin Config  -- ^ Deprecated
    , argsSessionLoadingOptions :: SessionLoadingOptions
    , argsIdeOptions            :: Config -> Action IdeGhcSession -> IdeOptions
    , argsLspOptions            :: LSP.Options
    , argsDefaultHlsConfig      :: Config
    , argsGetHieDbLoc           :: FilePath -> IO FilePath -- ^ Map project roots to the location of the hiedb for the project
    , argsDebouncer             :: IO (Debouncer NormalizedUri) -- ^ Debouncer used for diagnostics
    , argsHandleIn              :: IO Handle
    , argsHandleOut             :: IO Handle
    , argsThreads               :: Maybe Natural
    , argsMonitoring            :: IO Monitoring
    , argsDisableKick           :: Bool -- ^ flag to disable kick used for testing
    }

defaultArguments :: Recorder (WithPriority Log) -> FilePath -> IdePlugins IdeState -> Arguments
defaultArguments recorder projectRoot plugins = Arguments
        { argsProjectRoot = projectRoot -- ^ see Note [Root Directory]
        , argCommand = LSP
        , argsRules = mainRule (cmapWithPrio LogRules recorder) def
        , argsGhcidePlugin = mempty
        , argsHlsPlugins = pluginDescToIdePlugins (GhcIde.descriptors (cmapWithPrio LogGhcIde recorder)) <> plugins
        , argsSessionLoadingOptions = def
        , argsIdeOptions = \config ghcSession -> (defaultIdeOptions ghcSession)
            { optCheckProject = pure $ checkProject config
            , optCheckParents = pure $ checkParents config
            }
        , argsLspOptions = def
            { LSP.optCompletionTriggerCharacters = Just "."
            -- Generally people start to notice that something is taking a while at about 1s, so
            -- that's when we start reporting progress
            , LSP.optProgressStartDelay = 1_000_000
            -- Once progress is being reported, it's nice to see that it's moving reasonably quickly,
            -- but not so fast that it's ugly. This number is a bit made up
            , LSP.optProgressUpdateDelay = 1_00_000
            }
        , argsDefaultHlsConfig = def
        , argsGetHieDbLoc = getHieDbLoc
        , argsDebouncer = newAsyncDebouncer
        , argsThreads = Nothing
        , argsHandleIn = pure stdin
        , argsHandleOut = do
                -- Move stdout to another file descriptor and duplicate stderr
                -- to stdout. This guards against stray prints from corrupting the JSON-RPC
                -- message stream.
                newStdout <- hDuplicate stdout
                stderr `hDuplicateTo'` stdout
                hSetBuffering stdout NoBuffering

                -- Print out a single space to assert that the above redirection works.
                -- This is interleaved with the logger, hence we just print a space here in
                -- order not to mess up the output too much. Verified that this breaks
                -- the language server tests without the redirection.
                putStr " " >> hFlush stdout
                return newStdout
        , argsMonitoring = OpenTelemetry.monitoring
        , argsDisableKick = False
        }


testing :: Recorder (WithPriority Log) -> FilePath -> IdePlugins IdeState -> Arguments
testing recorder projectRoot plugins =
  let
    arguments@Arguments{ argsHlsPlugins, argsIdeOptions, argsLspOptions } =
        defaultArguments recorder projectRoot plugins
    hlsPlugins = pluginDescToIdePlugins $
      idePluginsToPluginDesc argsHlsPlugins
      ++ [Test.blockCommandDescriptor "block-command", Test.plugin]
    ideOptions config sessionLoader =
      let
        defOptions = argsIdeOptions config sessionLoader
      in
        defOptions{ optTesting = IdeTesting True }
    lspOptions = argsLspOptions { LSP.optProgressStartDelay = 0, LSP.optProgressUpdateDelay = 0 }
  in
    arguments
      { argsHlsPlugins = hlsPlugins
      , argsIdeOptions = ideOptions
      , argsLspOptions = lspOptions
      }

defaultMain :: Recorder (WithPriority Log) -> Arguments -> IO ()
defaultMain recorder Arguments{..} = withHeapStats (cmapWithPrio LogHeapStats recorder) fun
 where
  fun = do
    setLocaleEncoding utf8
    pid <- T.pack . show <$> getProcessID
    hSetBuffering stderr LineBuffering

    let hlsPlugin = asGhcIdePlugin (cmapWithPrio LogPluginHLS recorder) argsHlsPlugins
        hlsCommands = allLspCmdIds' pid argsHlsPlugins
        plugins = hlsPlugin <> argsGhcidePlugin
        options = argsLspOptions {
          LSP.optExecuteCommandCommands = LSP.optExecuteCommandCommands argsLspOptions <> Just hlsCommands,
          LSP.optWorkspaceWillRenameFileOperationRegistrationOptions = Just $
            LSP.FileOperationRegistrationOptions
              [LSP.FileOperationFilter
              {_scheme= Just "file", _pattern = LSP.FileOperationPattern
                  { {-|
                  The glob pattern to match. Glob patterns can have the following syntax:
                  - `*` to match one or more characters in a path segment
                  - `?` to match on one character in a path segment
                  - `**` to match any number of path segments, including none
                  - `{}` to group sub patterns into an OR expression. (e.g. `**​/*.{ts,js}` matches all TypeScript and JavaScript files)
                  - `[]` to declare a range of characters to match in a path segment (e.g., `example.[0-9]` to match on `example.0`, `example.1`, …)
                  - `[!...]` to negate a range of characters to match in a path segment (e.g., `example.[!0-9]` to match on `example.a`, `example.b`, but not `example.0`)
                  -}
                  _glob = "**/*.hs"
                  , {-|
                  Whether to match files or folders with this pattern.

                  Matches both if undefined.
                  -}
                  _matches = Nothing
                  , {-|
                  Additional options used during matching.
                  -}
                  _options = Nothing
                }
              }],
          LSP.optWorkspaceDidRenameFileOperationRegistrationOptions = Just $
           LSP.FileOperationRegistrationOptions
              [LSP.FileOperationFilter
              {_scheme= Just "file", _pattern = LSP.FileOperationPattern
                  { {-|
                  The glob pattern to match. Glob patterns can have the following syntax:
                  - `*` to match one or more characters in a path segment
                  - `?` to match on one character in a path segment
                  - `**` to match any number of path segments, including none
                  - `{}` to group sub patterns into an OR expression. (e.g. `**​/*.{ts,js}` matches all TypeScript and JavaScript files)
                  - `[]` to declare a range of characters to match in a path segment (e.g., `example.[0-9]` to match on `example.0`, `example.1`, …)
                  - `[!...]` to negate a range of characters to match in a path segment (e.g., `example.[!0-9]` to match on `example.a`, `example.b`, but not `example.0`)
                  -}
                  _glob = "**/*.hs"
                  , {-|
                  Whether to match files or folders with this pattern.

                  Matches both if undefined.
                  -}
                  _matches = Nothing
                  , {-|
                  Additional options used during matching.
                  -}
                  _options = Nothing
                }
              }]
          }
        argsParseConfig = getConfigFromNotification argsHlsPlugins
        rules = do
            argsRules
            unless argsDisableKick $ action kick
            pluginRules plugins
        -- install the main and ghcide-plugin rules
        -- install the kick action, which triggers a typecheck on every
        -- Shake database restart, i.e. on every user edit.

    debouncer <- argsDebouncer
    inH <- argsHandleIn
    outH <- argsHandleOut

    numProcessors <- getNumProcessors
    let numCapabilities = max 1 $ maybe (numProcessors `div` 2) fromIntegral argsThreads

    case argCommand of
        LSP -> withNumCapabilities numCapabilities $ do
            ioT <- offsetTime
            logWith recorder Info $ LogLspStart (pluginId <$> ipMap argsHlsPlugins)

            let getIdeState :: MVar IdeState -> LSP.LanguageContextEnv Config -> FilePath -> WithHieDb -> Shake.ThreadQueue -> IO IdeState
                getIdeState ideStateVar env rootPath withHieDb threadQueue = do
                  t <- ioT
                  logWith recorder Info $ LogLspStartDuration t
                  sessionLoader <- loadSessionWithOptions (cmapWithPrio LogSession recorder) argsSessionLoadingOptions rootPath (tLoaderQueue threadQueue)
                  config <- LSP.runLspT env LSP.getConfig
                  let def_options = argsIdeOptions config sessionLoader

                  -- disable runSubset if the client doesn't support watched files
                  runSubset <- (optRunSubset def_options &&) <$> LSP.runLspT env isWatchSupported
                  logWith recorder Debug $ LogShouldRunSubset runSubset

                  let ideOptions = def_options
                              { optReportProgress = clientSupportsProgress caps
                              , optModifyDynFlags = optModifyDynFlags def_options <> pluginModifyDynflags plugins
                              , optRunSubset = runSubset
                              }
                      caps = LSP.resClientCapabilities env
                  monitoring <- argsMonitoring
                  ide <- initialise
                      (cmapWithPrio LogService recorder)
                      argsDefaultHlsConfig
                      argsHlsPlugins
                      rules
                      (Just env)
                      debouncer
                      ideOptions
                      withHieDb
                      threadQueue
                      monitoring
                      rootPath
                  putMVar ideStateVar ide
                  pure ide

            let setup ideStateVar = setupLSP (cmapWithPrio LogLanguageServer recorder) argsProjectRoot argsGetHieDbLoc (pluginHandlers plugins) (getIdeState ideStateVar)
                -- See Note [Client configuration in Rules]
                onConfigChange ideStateVar cfg = do
                  -- TODO: this is nuts, we're converting back to JSON just to get a fingerprint
                  let cfgObj = J.toJSON cfg
                  mide <- liftIO $ tryReadMVar ideStateVar
                  case mide of
                    Nothing -> pure ()
                    Just ide -> liftIO $ do
                        let msg = T.pack $ show cfg
                        setSomethingModified Shake.VFSUnmodified ide "config change" $ do
                            logWith recorder Debug $ LogConfigurationChange msg
                            modifyClientSettings ide (const $ Just cfgObj)
                            return [toNoFileKey Rules.GetClientSettings]

            do
                ideStateVar <- newEmptyMVar
                runLanguageServer (cmapWithPrio LogLanguageServer recorder) options inH outH argsDefaultHlsConfig argsParseConfig (onConfigChange ideStateVar) (setup ideStateVar)
            dumpSTMStats
        Check argFiles -> do
          let dir = argsProjectRoot
          dbLoc <- getHieDbLoc dir
          runWithWorkerThreads (cmapWithPrio LogSession recorder) dbLoc $ \hiedb threadQueue -> do
            -- GHC produces messages with UTF8 in them, so make sure the terminal doesn't error
            hSetEncoding stdout utf8
            hSetEncoding stderr utf8

            putStrLn $ "ghcide setup tester in " ++ dir ++ "."
            putStrLn "Report bugs at https://github.com/haskell/haskell-language-server/issues"

            putStrLn $ "\nStep 1/4: Finding files to test in " ++ dir
            files <- expandFiles recorder (argFiles ++ ["." | null argFiles])
            -- LSP works with absolute file paths, so try and behave similarly
            absoluteFiles <- nubOrd <$> mapM IO.canonicalizePath files
            putStrLn $ "Found " ++ show (length absoluteFiles) ++ " files"

            putStrLn "\nStep 2/4: Looking for hie.yaml files that control setup"
            cradles <- mapM findCradle absoluteFiles
            let ucradles = nubOrd cradles
            let n = length ucradles
            putStrLn $ "Found " ++ show n ++ " cradle" ++ ['s' | n /= 1]
            when (n > 0) $ putStrLn $ "  (" ++ intercalate ", " (catMaybes ucradles) ++ ")"
            putStrLn "\nStep 3/4: Initializing the IDE"
            sessionLoader <- loadSessionWithOptions (cmapWithPrio LogSession recorder) argsSessionLoadingOptions dir (tLoaderQueue threadQueue)
            let def_options = argsIdeOptions argsDefaultHlsConfig sessionLoader
                ideOptions = def_options
                        { optCheckParents = pure NeverCheck
                        , optCheckProject = pure False
                        , optModifyDynFlags = optModifyDynFlags def_options <> pluginModifyDynflags plugins
                        }
            ide <- initialise (cmapWithPrio LogService recorder) argsDefaultHlsConfig argsHlsPlugins rules Nothing debouncer ideOptions hiedb threadQueue mempty dir
            shakeSessionInit (cmapWithPrio LogShake recorder) ide
            registerIdeConfiguration (shakeExtras ide) $ IdeConfiguration mempty (hashed Nothing)

            putStrLn "\nStep 4/4: Type checking the files"
            setFilesOfInterest ide $ HashMap.fromList $ map ((,OnDisk) . toNormalizedFilePath') absoluteFiles
            results <- runAction "User TypeCheck" ide $ uses TypeCheck (map toNormalizedFilePath' absoluteFiles)
            _results <- runAction "GetHie" ide $ uses GetHieAst (map toNormalizedFilePath' absoluteFiles)
            _results <- runAction "GenerateCore" ide $ uses GenerateCore (map toNormalizedFilePath' absoluteFiles)
            let (worked, failed) = partition fst $ zip (map isJust results) absoluteFiles
            when (failed /= []) $
                putStr $ unlines $ "Files that failed:" : map ((++) " * " . snd) failed

            let nfiles xs = let n' = length xs in if n' == 1 then "1 file" else show n' ++ " files"
            putStrLn $ "\nCompleted (" ++ nfiles worked ++ " worked, " ++ nfiles failed ++ " failed)"

            unless (null failed) (exitWith $ ExitFailure (length failed))
        Db opts cmd -> do
            let root = argsProjectRoot
            dbLoc <- getHieDbLoc root
            hPutStrLn stderr $ "Using hiedb at: " ++ dbLoc
            mlibdir <- getInitialGhcLibDirDefault (cmapWithPrio LogSession recorder) root
            rng <- newStdGen
            case mlibdir of
                Nothing     -> exitWith $ ExitFailure 1
                Just libdir -> retryOnSqliteBusy (cmapWithPrio LogSession recorder) rng (HieDb.runCommand libdir opts{HieDb.database = dbLoc} cmd)

        Custom (IdeCommand c) -> do
          let root = argsProjectRoot
          dbLoc <- getHieDbLoc root
          runWithWorkerThreads (cmapWithPrio LogSession recorder) dbLoc $ \hiedb threadQueue -> do
            sessionLoader <- loadSessionWithOptions (cmapWithPrio LogSession recorder) argsSessionLoadingOptions "." (tLoaderQueue threadQueue)
            let def_options = argsIdeOptions argsDefaultHlsConfig sessionLoader
                ideOptions = def_options
                    { optCheckParents = pure NeverCheck
                    , optCheckProject = pure False
                    , optModifyDynFlags = optModifyDynFlags def_options <> pluginModifyDynflags plugins
                    }
            ide <- initialise (cmapWithPrio LogService recorder) argsDefaultHlsConfig argsHlsPlugins rules Nothing debouncer ideOptions hiedb threadQueue mempty root
            shakeSessionInit (cmapWithPrio LogShake recorder) ide
            registerIdeConfiguration (shakeExtras ide) $ IdeConfiguration mempty (hashed Nothing)
            c ide

-- | List the haskell files given some paths
--
-- It will rely on git if possible to filter-out ignored files.
expandFiles :: Recorder (WithPriority Log) -> [FilePath] -> IO [FilePath]
expandFiles recorder paths = do
  let haskellFind x =
        let recurse "." = True
            recurse y | "." `isPrefixOf` takeFileName y = False -- skip .git etc
            recurse y = takeFileName y `notElem` ["dist", "dist-newstyle"] -- cabal directories
        in filter (\y -> takeExtension y `elem` [".hs", ".lhs"]) <$> IO.listFilesInside (return . recurse) x
      git args = do
        mResult <- (Just <$> readProcessWithExitCode "git" args "") `Safe.catchAny`const (pure Nothing)
        pure $
            case mResult of
              Just (ExitSuccess, gitStdout, _) -> Just gitStdout
              _                                -> Nothing
  mHasGit <- git ["status"]
  when (isJust mHasGit) $ logWith recorder Info LogUsingGit
  let findFiles =
        case mHasGit of
          Just _ -> \path -> do
            let lookups =
                  if takeExtension path `elem` [".hs", ".lhs"]
                      then [path]
                      else [path </> "*.hs", path </> "*.lhs"]
                gitLines args = fmap lines <$> git args
            mTracked <- gitLines ("ls-files":lookups)
            mUntracked <- gitLines ("ls-files":"-o":lookups)
            case mTracked <> mUntracked of
              Nothing    -> haskellFind path
              Just files -> pure files
          _ -> haskellFind

  flip concatMapM paths $ \x -> do
    b <- IO.doesFileExist x
    if b
        then return [x]
        else do
            files <- findFiles x
            when (null files) $
                fail $ "Couldn't find any .hs/.lhs files inside directory: " ++ x
            return files