Fix most hlint warnings in ghcide

ghcide/session-loader/Development/IDE/Session.hs

@@ -534,7 +534,7 @@ loadSessionWithOptions recorder SessionLoadingOptions{..} dir = do
                   -- compilation but these are the true source of
                   -- information.
                   new_deps = fmap (\(df, targets) -> RawComponentInfo (homeUnitId_ df) df targets cfp opts dep_info) newTargetDfs
-                  all_deps = new_deps `NE.appendList` maybe [] id oldDeps
+                  all_deps = new_deps `NE.appendList` fromMaybe [] oldDeps
                   -- Get all the unit-ids for things in this component
                   _inplace = map rawComponentUnitId $ NE.toList all_deps
 
@@ -594,7 +594,7 @@ loadSessionWithOptions recorder SessionLoadingOptions{..} dir = do
           void $ modifyVar' fileToFlags $
               Map.insert hieYaml this_flags_map
           void $ modifyVar' filesMap $
-              flip HM.union (HM.fromList (zip (map fst $ concatMap toFlagsMap all_targets) (repeat hieYaml)))
+              flip HM.union (HM.fromList (map ((,hieYaml) . fst) $ concatMap toFlagsMap all_targets))
 
           void $ extendKnownTargets all_targets
 
@@ -685,7 +685,7 @@ loadSessionWithOptions recorder SessionLoadingOptions{..} dir = do
                   -- again.
                   modifyVar_ fileToFlags (const (return Map.empty))
                   -- Keep the same name cache
-                  modifyVar_ hscEnvs (return . Map.adjust (\_ -> []) hieYaml )
+                  modifyVar_ hscEnvs (return . Map.adjust (const []) hieYaml )
                   consultCradle hieYaml cfp
                 else return (opts, Map.keys old_di)
             Nothing -> consultCradle hieYaml cfp

ghcide/session-loader/Development/IDE/Session/Implicit.hs

@@ -3,26 +3,27 @@ module Development.IDE.Session.Implicit
   ) where
 
 
-import           Control.Applicative               ((<|>))
+import           Control.Applicative       ((<|>))
+import           Control.Exception         (handleJust)
 import           Control.Monad
-import           Control.Monad.Trans.Maybe
 import           Control.Monad.IO.Class
-import           Control.Exception (handleJust)
+import           Control.Monad.Trans.Maybe
 import           Data.Bifunctor
+import           Data.Functor              ((<&>))
 import           Data.Maybe
 import           Data.Void
+import           System.Directory          hiding (findFile)
 import           System.FilePath
-import           System.Directory                  hiding (findFile)
 import           System.IO.Error
 
-import           Colog.Core                        (LogAction (..), WithSeverity (..))
-import           HIE.Bios.Cradle                   (getCradle, defaultCradle)
+import           Colog.Core                (LogAction (..), WithSeverity (..))
 import           HIE.Bios.Config
-import           HIE.Bios.Types                    hiding (ActionName(..))
+import           HIE.Bios.Cradle           (defaultCradle, getCradle)
+import           HIE.Bios.Types            hiding (ActionName (..))
 
-import           Hie.Locate
 import           Hie.Cabal.Parser
-import qualified Hie.Yaml                          as Implicit
+import           Hie.Locate
+import qualified Hie.Yaml                  as Implicit
 
 loadImplicitCradle :: Show a => LogAction IO (WithSeverity Log) -> FilePath -> IO (Cradle a)
 loadImplicitCradle l wfile = do
@@ -50,11 +51,11 @@ inferCradleTree start_dir =
    <|> (cabalExecutable >> cabalConfigDir start_dir >>= \dir -> cabalWorkDir dir >> pure (simpleCabalCradle dir))
    <|> (stackExecutable >> stackConfigDir start_dir >>= \dir -> stackWorkDir dir >> stackCradle dir)
    -- If we have a cabal.project OR we have a .cabal and dist-newstyle, prefer cabal
-   <|> (cabalExecutable >> (cabalConfigDir start_dir <|> cabalFileAndWorkDir) >>= pure . simpleCabalCradle)
+   <|> (cabalExecutable >> (cabalConfigDir start_dir <|> cabalFileAndWorkDir) <&> simpleCabalCradle)
    -- If we have a stack.yaml, use stack
    <|> (stackExecutable >> stackConfigDir start_dir >>= stackCradle)
    -- If we have a cabal file, use cabal
-   <|> (cabalExecutable >> cabalFileDir start_dir >>= pure . simpleCabalCradle)
+   <|> (cabalExecutable >> cabalFileDir start_dir <&> simpleCabalCradle)
 
   where
   maybeItsBios = (\wdir -> (Bios (Program $ wdir </> ".hie-bios") Nothing Nothing, wdir)) <$> biosWorkDir start_dir

ghcide/src/Development/IDE/Core/Compile.hs

@@ -297,8 +297,8 @@ captureSplicesAndDeps TypecheckHelpers{..} env k = do
 #endif
 
                                          | n <- concatMap (uniqDSetToList . bcoFreeNames) $ bc_bcos bcos
-                                         , Just mod <- [nameModule_maybe n] -- Names from other modules
                                          , not (isWiredInName n) -- Exclude wired-in names
+                                         , Just mod <- [nameModule_maybe n] -- Names from other modules
                                          , moduleUnitId mod `elem` home_unit_ids -- Only care about stuff from the home package set
                                          ]
                  home_unit_ids =
@@ -340,7 +340,7 @@ captureSplicesAndDeps TypecheckHelpers{..} env k = do
 #else
              {- load it -}
            ; fv_hvs <- loadDecls (hscInterp hsc_env') hsc_env' srcspan bcos
-           ; let hval = (expectJust "hscCompileCoreExpr'" $ lookup (idName binding_id) fv_hvs)
+           ; let hval = expectJust "hscCompileCoreExpr'" $ lookup (idName binding_id) fv_hvs
 #endif
 
            ; modifyIORef' var (flip extendModuleEnvList [(mi_module $ hm_iface hm, linkableHash lb) | lb <- lbs, let hm = linkableHomeMod lb])
@@ -595,7 +595,7 @@ mkHiFileResultCompile se session' tcm simplified_guts = catchErrs $ do
           -- SYB is slow but fine given that this is only used for testing
           noUnfoldings = everywhere $ mkT $ \v -> if isId v
             then
-              let v' = if isOtherUnfolding (realIdUnfolding v) then (setIdUnfolding v noUnfolding) else v
+              let v' = if isOtherUnfolding (realIdUnfolding v) then setIdUnfolding v noUnfolding else v
                 in setIdOccInfo v' noOccInfo
             else v
           isOtherUnfolding (OtherCon _) = True
@@ -1256,9 +1256,9 @@ parseHeader
        -> FilePath  -- ^ the filename (for source locations)
        -> Util.StringBuffer -- ^ Haskell module source text (full Unicode is supported)
 #if MIN_VERSION_ghc(9,5,0)
-       -> ExceptT [FileDiagnostic] m ([FileDiagnostic], Located(HsModule GhcPs))
+       -> ExceptT [FileDiagnostic] m ([FileDiagnostic], Located (HsModule GhcPs))
 #else
-       -> ExceptT [FileDiagnostic] m ([FileDiagnostic], Located(HsModule))
+       -> ExceptT [FileDiagnostic] m ([FileDiagnostic], Located HsModule)
 #endif
 parseHeader dflags filename contents = do
    let loc  = mkRealSrcLoc (Util.mkFastString filename) 1 1
@@ -1748,19 +1748,19 @@ pathToModuleName = mkModuleName . map rep
 
   - CPP clauses should be placed at the end of the imports section. The clauses
   should be ordered by the GHC version they target from earlier to later versions,
-  with negative if clauses coming before positive if clauses of the same 
-  version. (If you think about which GHC version a clause activates for this 
+  with negative if clauses coming before positive if clauses of the same
+  version. (If you think about which GHC version a clause activates for this
   should make sense `!MIN_VERSION_GHC(9,0,0)` refers to 8.10 and lower which is
-  a earlier version than `MIN_VERSION_GHC(9,0,0)` which refers to versions 9.0 
+  a earlier version than `MIN_VERSION_GHC(9,0,0)` which refers to versions 9.0
   and later). In addition there should be a space before and after each CPP
   clause.
 
-  - In if clauses that use `&&` and depend on more than one statement, the 
+  - In if clauses that use `&&` and depend on more than one statement, the
   positive statement should come before the negative statement. In addition the
   clause should come after the single positive clause for that GHC version.
 
-  - There shouldn't be multiple identical CPP statements. The use of odd or even 
+  - There shouldn't be multiple identical CPP statements. The use of odd or even
   GHC numbers is identical, with the only preference being to use what is
-  already there. (i.e. (`MIN_VERSION_GHC(9,2,0)` and `MIN_VERSION_GHC(9,1,0)` 
+  already there. (i.e. (`MIN_VERSION_GHC(9,2,0)` and `MIN_VERSION_GHC(9,1,0)`
   are functionally equivalent)
 -}

ghcide/src/Development/IDE/Core/FileStore.hs

@@ -265,7 +265,7 @@ registerFileWatches globs = do
           -- our purposes.
           registration = LSP.TRegistration { _id ="globalFileWatches"
                                            , _method = LSP.SMethod_WorkspaceDidChangeWatchedFiles
-                                           , _registerOptions = Just $ regOptions}
+                                           , _registerOptions = Just regOptions}
           regOptions =
             DidChangeWatchedFilesRegistrationOptions { _watchers = watchers }
           -- See Note [File existence cache and LSP file watchers] for why this exists, and the choice of watch kind

ghcide/src/Development/IDE/Core/Rules.hs

@@ -372,7 +372,7 @@ getLocatedImportsRule recorder =
         let import_dirs = deps env_eq
         let dflags = hsc_dflags env
             isImplicitCradle = isNothing $ envImportPaths env_eq
-        dflags' <- return $ if isImplicitCradle
+        let dflags' = if isImplicitCradle
                     then addRelativeImport file (moduleName $ ms_mod ms) dflags
                     else dflags
         opt <- getIdeOptions
@@ -538,7 +538,7 @@ reportImportCyclesRule recorder =
                   let cycles = mapMaybe (cycleErrorInFile fileId) (toList errs)
                   -- Convert cycles of files into cycles of module names
                   forM cycles $ \(imp, files) -> do
-                      modNames <- forM files $ 
+                      modNames <- forM files $
                           getModuleName . idToPath depPathIdMap
                       pure $ toDiag imp $ sort modNames
     where cycleErrorInFile f (PartOfCycle imp fs)
@@ -701,7 +701,7 @@ dependencyInfoForFiles fs = do
         -- 'extendModSummaryNoDeps'.
         -- This may have to change in the future.
           map extendModSummaryNoDeps $
-          (catMaybes mss)
+          catMaybes mss
 #endif
   pure (fingerprintToBS $ Util.fingerprintFingerprints $ map (maybe fingerprint0 msrFingerprint) msrs, processDependencyInformation rawDepInfo bm mg)
 
@@ -1170,7 +1170,7 @@ getLinkableType f = use_ NeedsCompilation f
 -- needsCompilationRule :: Rules ()
 needsCompilationRule :: NormalizedFilePath  -> Action (IdeResultNoDiagnosticsEarlyCutoff (Maybe LinkableType))
 needsCompilationRule file
-  | "boot" `isSuffixOf` (fromNormalizedFilePath file) =
+  | "boot" `isSuffixOf` fromNormalizedFilePath file =
     pure (Just $ encodeLinkableType Nothing, Just Nothing)
 needsCompilationRule file = do
   graph <- useNoFile GetModuleGraph

ghcide/src/Development/IDE/Core/Shake.hs

@@ -189,7 +189,7 @@ import           Development.IDE.GHC.Compat             (mkSplitUniqSupply,
 data Log
   = LogCreateHieDbExportsMapStart
   | LogCreateHieDbExportsMapFinish !Int
-  | LogBuildSessionRestart !String ![DelayedActionInternal] !(KeySet) !Seconds !(Maybe FilePath)
+  | LogBuildSessionRestart !String ![DelayedActionInternal] !KeySet !Seconds !(Maybe FilePath)
   | LogBuildSessionRestartTakingTooLong !Seconds
   | LogDelayedAction !(DelayedAction ()) !Seconds
   | LogBuildSessionFinish !(Maybe SomeException)
@@ -1276,7 +1276,7 @@ updateFileDiagnostics recorder fp ver k ShakeExtras{diagnostics, hiddenDiagnosti
                             liftIO $ tag "count" (show $ Prelude.length newDiags)
                             liftIO $ tag "key" (show k)
                             LSP.sendNotification SMethod_TextDocumentPublishDiagnostics $
-                                LSP.PublishDiagnosticsParams (fromNormalizedUri uri') (fmap fromIntegral ver) ( newDiags)
+                                LSP.PublishDiagnosticsParams (fromNormalizedUri uri') (fmap fromIntegral ver) newDiags
                  return action
     where
         diagsFromRule :: Diagnostic -> Diagnostic

ghcide/src/Development/IDE/GHC/Compat/Outputable.hs

@@ -137,11 +137,11 @@ pprNoLocMsgEnvelope (MsgEnvelope { errMsgDiagnostic = e
   = sdocWithContext $ \_ctx ->
     withErrStyle unqual $
 #if MIN_VERSION_ghc(9,7,0)
-      (formatBulleted e)
+      formatBulleted e
 #elif MIN_VERSION_ghc(9,3,0)
-      (formatBulleted _ctx $ e)
+      formatBulleted _ctx $ e
 #else
-      (formatBulleted _ctx $ Error.renderDiagnostic e)
+      formatBulleted _ctx $ Error.renderDiagnostic e
 #endif
 
 

ghcide/src/Development/IDE/GHC/Compat/Units.hs

@@ -1,5 +1,4 @@
-{-# LANGUAGE CPP             #-}
-{-# LANGUAGE PatternSynonyms #-}
+{-# LANGUAGE CPP #-}
 
 -- | Compat module for 'UnitState' and 'UnitInfo'.
 module Development.IDE.GHC.Compat.Units (

ghcide/src/Development/IDE/GHC/CoreFile.hs

@@ -124,7 +124,7 @@ codeGutsToCoreFile hash CgGuts{..} = CoreFile (map (toIfaceTopBind1 cg_module) $
 -- | Implicit binds can be generated from the interface and are not tidied,
 -- so we must filter them out
 isNotImplictBind :: CoreBind -> Bool
-isNotImplictBind bind = any (not . isImplicitId) $ bindBindings bind
+isNotImplictBind bind = not . all isImplicitId $ bindBindings bind
 
 bindBindings :: CoreBind -> [Var]
 bindBindings (NonRec b _) = [b]
@@ -189,7 +189,7 @@ tcTopIfaceBindings1 :: IORef TypeEnv -> [TopIfaceBinding IfaceId]
           -> IfL [CoreBind]
 tcTopIfaceBindings1 ty_var ver_decls
    = do
-     int <- mapM (traverse $ tcIfaceId) ver_decls
+     int <- mapM (traverse tcIfaceId) ver_decls
      let all_ids = concatMap toList int
      liftIO $ modifyIORef ty_var (flip extendTypeEnvList $ map AnId all_ids)
      extendIfaceIdEnv all_ids $ mapM tc_iface_bindings int
@@ -212,7 +212,7 @@ tc_iface_bindings (TopIfaceNonRec v e) = do
   e' <- tcIfaceExpr e
   pure $ NonRec v e'
 tc_iface_bindings (TopIfaceRec vs) = do
-  vs' <- traverse (\(v, e) -> (,) <$> pure v <*> tcIfaceExpr e) vs
+  vs' <- traverse (\(v, e) -> (v,) <$> tcIfaceExpr e) vs
   pure $ Rec vs'
 
 -- | Prefixes that can occur in a GHC OccName

ghcide/src/Development/IDE/GHC/Orphans.hs

@@ -98,7 +98,7 @@ instance Ord FastString where
 instance NFData (SrcSpanAnn' a) where
     rnf = rwhnf
 
-instance Bifunctor (GenLocated) where
+instance Bifunctor GenLocated where
     bimap f g (L l x) = L (f l) (g x)
 
 deriving instance Functor SrcSpanAnn'

ghcide/src/Development/IDE/GHC/Util.hs

@@ -168,7 +168,7 @@ cgGutsToCoreModule safeMode guts modDetails = CoreModule
 --   Will produce an 8 byte unreadable ByteString.
 fingerprintToBS :: Fingerprint -> BS.ByteString
 fingerprintToBS (Fingerprint a b) = BS.unsafeCreate 8 $ \ptr -> do
-    ptr' <- pure $ castPtr ptr
+    let ptr' = castPtr ptr
     pokeElemOff ptr' 0 a
     pokeElemOff ptr' 1 b
 

ghcide/src/Development/IDE/Import/FindImports.hs

@@ -23,9 +23,9 @@ import           Development.IDE.Types.Location
 -- standard imports
 import           Control.Monad.Extra
 import           Control.Monad.IO.Class
-import           Data.List                         (isSuffixOf, find)
-import qualified Data.Set                          as S
+import           Data.List                         (find, isSuffixOf)
 import           Data.Maybe
+import qualified Data.Set                          as S
 import           System.FilePath
 
 -- See Note [Guidelines For Using CPP In GHCIDE Import Statements]
@@ -93,7 +93,7 @@ locateModuleFile import_dirss exts targetFor isSource modName = do
     Nothing ->
       case find (\(_ , _, reexports) -> S.member modName reexports) import_dirss of
         Just (uid,_,_) -> pure $ LocateFoundReexport uid
-        Nothing -> pure $ LocateNotFound
+        Nothing        -> pure LocateNotFound
     Just (uid,file) -> pure $ LocateFoundFile uid file
   where
     go (uid, candidate) = fmap ((uid,) <$>) $ targetFor modName candidate

ghcide/src/Development/IDE/LSP/LanguageServer.hs

@@ -110,7 +110,7 @@ runLanguageServer recorder options inH outH defaultConfig parseConfig onConfigCh
             -- TODO: magic string
             , LSP.configSection = "haskell"
             , LSP.doInitialize = doInitialize
-            , LSP.staticHandlers = (const staticHandlers)
+            , LSP.staticHandlers = const staticHandlers
             , LSP.interpretHandler = interpretHandler
             , LSP.options = modifyOptions options
             }

ghcide/src/Development/IDE/LSP/Outline.hs

@@ -274,7 +274,7 @@ hsConDeclsBinders cons
     get_flds_h98 _ = []
 
     get_flds_gadt :: HsConDeclGADTDetails GhcPs
-                  -> ([LFieldOcc GhcPs])
+                  -> [LFieldOcc GhcPs]
 #if MIN_VERSION_ghc(9,3,0)
     get_flds_gadt (RecConGADT flds _) = get_flds (reLoc flds)
 #else
@@ -283,7 +283,7 @@ hsConDeclsBinders cons
     get_flds_gadt _ = []
 
     get_flds :: Located [LConDeclField GhcPs]
-             -> ([LFieldOcc GhcPs])
+             -> [LFieldOcc GhcPs]
     get_flds flds = concatMap (cd_fld_names . unLoc) (unLoc flds)
 
 

ghcide/src/Development/IDE/Plugin/Completions/Logic.hs

@@ -704,7 +704,7 @@ getCompletions
               pn = showForSnippet name
               ty = showForSnippet <$> typ
               thisModName = Local $ nameSrcSpan name
-              dets = NameDetails <$> (nameModule_maybe name) <*> pure (nameOccName name)
+              dets = NameDetails <$> nameModule_maybe name <*> pure (nameOccName name)
 
           -- When record-dot-syntax completions are available, we return them exclusively.
           -- They are only available when we write i.e. `myrecord.` with OverloadedRecordDot enabled.
@@ -762,7 +762,7 @@ uniqueCompl candidate unique =
     EQ ->
       -- preserve completions for duplicate record fields where the only difference is in the type
       -- remove redundant completions with less type info than the previous
-      if (isLocalCompletion unique)
+      if isLocalCompletion unique
         -- filter global completions when we already have a local one
         || not(isLocalCompletion candidate) && isLocalCompletion unique
         then EQ

ghcide/src/Development/IDE/Plugin/TypeLenses.hs

@@ -183,7 +183,7 @@ codeLensResolveProvider ideState pId lens@CodeLens{_range} uri TypeLensesResolve
 
 generateLensCommand :: PluginId -> Uri -> T.Text -> TextEdit -> Command
 generateLensCommand pId uri title edit =
-  let wEdit = WorkspaceEdit (Just $ Map.singleton uri $ [edit]) Nothing Nothing
+  let wEdit = WorkspaceEdit (Just $ Map.singleton uri [edit]) Nothing Nothing
   in mkLspCommand pId (CommandId typeLensCommandId) title (Just [toJSON wEdit])
 
 -- Since the lenses are created with diagnostics, and since the globalTypeSig