Fix ghc and hlint warnings (#568)

* Fix ghc and hlint warnings

* exceptions needed with ghc 9.6+

* Small improvements

* Add -Wunused-packages, consolidate warning configs, fix few more warnings

* fourmolu

Author: jhrcek

cabal.project

@@ -15,7 +15,7 @@ package lsp
 
 package lsp-types
   -- This makes a big difference here as lsp-types
-  -- has very many independent modules 
+  -- has very many independent modules
   ghc-options: -j4
 
 -- We allow filepath-1.5, this lets us actually test it. There is no problem

lsp-test/bench/SimpleBench.hs

@@ -1,7 +1,6 @@
 {-# LANGUAGE DuplicateRecordFields #-}
 {-# LANGUAGE GADTs #-}
 {-# LANGUAGE OverloadedStrings #-}
-{-# LANGUAGE RankNTypes #-}
 
 module Main where
 

lsp-test/example/Test.hs

@@ -6,6 +6,7 @@ import Language.LSP.Protocol.Message
 import Language.LSP.Protocol.Types
 import Language.LSP.Test
 
+main :: IO ()
 main = runSession "lsp-demo-reactor-server" fullCaps "test/data/" $ do
   doc <- openDoc "Rename.hs" "haskell"
 

lsp-test/func-test/FuncTest.hs

@@ -15,14 +15,12 @@ import Control.Monad.IO.Class
 import Data.Aeson qualified as J
 import Data.Maybe
 import Data.Proxy
-import Data.Set qualified as Set
 import Language.LSP.Protocol.Lens qualified as L
 import Language.LSP.Protocol.Message
 import Language.LSP.Protocol.Types
 import Language.LSP.Server
 import Language.LSP.Test qualified as Test
 import System.Exit
-import System.IO
 import System.Process
 import Test.Hspec
 import UnliftIO

lsp-test/lsp-test.cabal

@@ -31,7 +31,11 @@ source-repository head
   type:     git
   location: https://github.com/haskell/lsp
 
+common warnings
+  ghc-options: -Wunused-packages
+
 library
+  import:             warnings
   hs-source-dirs:     src
   default-language:   GHC2021
   exposed-modules:    Language.LSP.Test
@@ -66,7 +70,6 @@ library
     , mtl                 >=2.2   && <2.4
     , parser-combinators  ^>=1.3
     , process             ^>=1.6
-    , row-types           ^>=1.0
     , some                ^>=1.0
     , text                >=1     && <2.2
     , time                >=1.10  && <1.13
@@ -90,6 +93,7 @@ library
   ghc-options:        -W
 
 test-suite tests
+  import:             warnings
   type:               exitcode-stdio-1.0
   hs-source-dirs:     test
   main-is:            Test.hs
@@ -115,6 +119,7 @@ test-suite tests
     , unliftio
 
 test-suite func-test
+  import:             warnings
   type:               exitcode-stdio-1.0
   hs-source-dirs:     func-test
   default-language:   GHC2021
@@ -123,7 +128,6 @@ test-suite func-test
     , base
     , aeson
     , co-log-core
-    , containers
     , hspec
     , lens
     , lsp
@@ -133,6 +137,7 @@ test-suite func-test
     , unliftio
 
 test-suite example
+  import:             warnings
   type:               exitcode-stdio-1.0
   hs-source-dirs:     example
   default-language:   GHC2021
@@ -145,11 +150,12 @@ test-suite example
   build-tool-depends: lsp:lsp-demo-reactor-server
 
 benchmark simple-bench
+  import:             warnings
   type:               exitcode-stdio-1.0
   hs-source-dirs:     bench
   default-language:   GHC2021
   main-is:            SimpleBench.hs
-  ghc-options:        -Wall -O2 -eventlog -rtsopts
+  ghc-options:        -Wall -O2 -rtsopts
   build-depends:
     , base
     , extra

lsp-test/src/Language/LSP/Test.hs

@@ -1,8 +1,8 @@
+{-# LANGUAGE DataKinds #-}
 {-# LANGUAGE DuplicateRecordFields #-}
 {-# LANGUAGE GADTs #-}
 {-# LANGUAGE LambdaCase #-}
 {-# LANGUAGE OverloadedStrings #-}
-{-# LANGUAGE TypeInType #-}
 
 {- |
 Module      : Language.LSP.Test
@@ -559,7 +559,7 @@ createDoc file languageId contents = do
   let pred :: SomeRegistration -> [TRegistration Method_WorkspaceDidChangeWatchedFiles]
       pred (SomeRegistration r@(TRegistration _ SMethod_WorkspaceDidChangeWatchedFiles _)) = [r]
       pred _ = mempty
-      regs = concatMap pred $ Map.elems dynCaps
+      regs = concatMap pred dynCaps
       watchHits :: FileSystemWatcher -> Bool
       watchHits (FileSystemWatcher (GlobPattern (InL (Pattern pattern))) kind) =
         -- If WatchKind is excluded, defaults to all true as per spec
@@ -740,7 +740,7 @@ getCodeActionContext doc = do
  Note that this does not wait for more to come in.
 -}
 getCurrentDiagnostics :: TextDocumentIdentifier -> Session [Diagnostic]
-getCurrentDiagnostics doc = fromMaybe [] . Map.lookup (toNormalizedUri $ doc ^. L.uri) . curDiagnostics <$> get
+getCurrentDiagnostics doc = Map.findWithDefault [] (toNormalizedUri $ doc ^. L.uri) . curDiagnostics <$> get
 
 -- | Returns the tokens of all progress sessions that have started but not yet ended.
 getIncompleteProgressSessions :: Session (Set.Set ProgressToken)

lsp-test/src/Language/LSP/Test/Compat.hs

@@ -1,7 +1,6 @@
 {-# LANGUAGE CPP #-}
 {-# LANGUAGE DataKinds #-}
 {-# LANGUAGE DuplicateRecordFields #-}
-{-# LANGUAGE OverloadedLabels #-}
 {-# LANGUAGE OverloadedStrings #-}
 -- For some reason ghc warns about not using
 -- Control.Monad.IO.Class but it's needed for
@@ -103,7 +102,7 @@ cleanupProcess (mb_stdin, mb_stdout, mb_stderr, ph) = do
     return ()
   where ignoreSigPipe = ignoreIOError ResourceVanished ePIPE
         ignorePermDenied = ignoreIOError PermissionDenied eACCES
-    
+
 ignoreIOError :: IOErrorType -> Errno -> IO () -> IO ()
 ignoreIOError ioErrorType errno =
   C.handle $ \e -> case e of

lsp-test/src/Language/LSP/Test/Decoding.hs

@@ -1,6 +1,6 @@
+{-# LANGUAGE DataKinds #-}
 {-# LANGUAGE GADTs #-}
 {-# LANGUAGE OverloadedStrings #-}
-{-# LANGUAGE TypeInType #-}
 
 module Language.LSP.Test.Decoding where
 
@@ -10,7 +10,6 @@ import Data.Aeson
 import Data.Aeson.Types
 import Data.ByteString.Lazy.Char8 qualified as B
 import Data.Foldable
-import Data.Functor.Const
 import Data.Functor.Product
 import Data.Maybe
 import Language.LSP.Protocol.Lens qualified as L
@@ -82,7 +81,7 @@ decodeFromServerMsg reqMap bytes = unP $ parse p obj
     let (mm, newMap) = pickFromIxMap lid reqMap
      in case mm of
           Nothing -> Nothing
-          Just m -> Just $ (m, Pair m (Const newMap))
+          Just m -> Just (m, Pair m (Const newMap))
   unP (Success (FromServerMess m msg)) = (reqMap, FromServerMess m msg)
   unP (Success (FromServerRsp (Pair m (Const newMap)) msg)) = (newMap, FromServerRsp m msg)
   unP (Error e) = error $ "Error decoding " <> show obj <> " :" <> e

lsp-test/src/Language/LSP/Test/Files.hs

@@ -1,6 +1,6 @@
+{-# LANGUAGE DataKinds #-}
 {-# LANGUAGE GADTs #-}
 {-# LANGUAGE OverloadedStrings #-}
-{-# LANGUAGE TypeInType #-}
 
 module Language.LSP.Test.Files (
   swapFiles,
@@ -83,18 +83,13 @@ mapUris f event =
         swapDocumentChangeUri (InR (InR (InL renameFile))) = InR $ InR $ InL $ L.newUri .~ f (renameFile ^. L.newUri) $ renameFile
         swapDocumentChangeUri (InR (InR (InR deleteFile))) = InR $ InR $ InR $ swapUri id deleteFile
      in e
-          & L.changes . _Just %~ swapKeys f
+          & L.changes . _Just %~ M.mapKeys f
           & L.documentChanges . _Just . traversed %~ swapDocumentChangeUri
 
-  swapKeys :: (Uri -> Uri) -> M.Map Uri b -> M.Map Uri b
-  swapKeys f = M.foldlWithKey' (\acc k v -> M.insert (f k) v acc) M.empty
-
   swapUri :: L.HasUri b Uri => Lens' a b -> a -> a
-  swapUri lens x =
-    let newUri = f (x ^. lens . L.uri)
-     in (lens . L.uri) .~ newUri $ x
+  swapUri lens = (lens . L.uri) %~ f
 
-  -- \| Transforms rootUri/rootPath.
+  -- Transforms rootUri/rootPath.
   transformInit :: InitializeParams -> InitializeParams
   transformInit x =
     let modifyRootPath p =

lsp-test/src/Language/LSP/Test/Parsing.hs

@@ -1,7 +1,7 @@
+{-# LANGUAGE DataKinds #-}
 {-# LANGUAGE GADTs #-}
 {-# LANGUAGE LambdaCase #-}
 {-# LANGUAGE OverloadedStrings #-}
-{-# LANGUAGE TypeInType #-}
 
 module Language.LSP.Test.Parsing (
   -- $receiving