Fix -Wall and -Wunused-packages in hls-class-plugin (#3972)

* Fix -Wunused-packages in class plugin

* -Wall and hlint fixes

* Fix type annotation for ghc 9.6+

Author: jhrcek

plugins/hls-class-plugin/hls-class-plugin.cabal

@@ -24,7 +24,11 @@ source-repository head
     type:     git
     location: https://github.com/haskell/haskell-language-server.git
 
+common warnings
+  ghc-options: -Wall -Wno-unticked-promoted-constructors -Wno-name-shadowing -Wunused-packages
+
 library
+  import: warnings
   -- Plugins that need exactprint have not been updated for 9.8 yet
   if impl(ghc >= 9.8)
     buildable: False
@@ -46,7 +50,6 @@ library
     , ghc
     , ghc-exactprint  >= 1.5
     , ghcide          == 2.6.0.0
-    , ghc-boot-th
     , hls-graph
     , hls-plugin-api  == 2.6.0.0
     , lens
@@ -61,9 +64,8 @@ library
     TypeOperators
     OverloadedStrings
 
-  ghc-options:        -Wall -Wno-unticked-promoted-constructors -Wno-name-shadowing
-
 test-suite tests
+  import: warnings
   if impl(ghc >= 9.8)
     buildable: False
   else
@@ -74,12 +76,10 @@ test-suite tests
   main-is:          Main.hs
   ghc-options:      -threaded -rtsopts -with-rtsopts=-N
   build-depends:
-    , aeson
     , base
     , filepath
     , ghcide
     , hls-class-plugin
-    , hls-plugin-api
     , hls-test-utils     == 2.6.0.0
     , lens
     , lsp-types

plugins/hls-class-plugin/src/Ide/Plugin/Class/CodeAction.hs

@@ -43,7 +43,7 @@ import           Language.LSP.Server
 
 addMethodPlaceholders :: PluginId -> CommandFunction IdeState AddMinimalMethodsParams
 addMethodPlaceholders _ state param@AddMinimalMethodsParams{..} = do
-    caps <- lift $ getClientCapabilities
+    caps <- lift getClientCapabilities
     nfp <- getNormalizedFilePathE (verTxtDocId ^. L.uri)
     pm <- runActionE "classplugin.addMethodPlaceholders.GetParsedModule" state
         $ useE GetParsedModule nfp
@@ -239,6 +239,6 @@ minDefToMethodGroups hsc gblEnv range sigs minDef = makeMethodGroup <$> go minDe
 
         go (Var mn)   = pure $ makeMethodDefinitions hsc gblEnv range $ filter ((==) (printOutputable mn) . signatureToName) sigs
         go (Or ms)    = concatMap (go . unLoc) ms
-        go (And ms)   = foldr (liftA2 (<>)) [[]] (fmap (go . unLoc) ms)
+        go (And ms)   = foldr (liftA2 (<>) . go . unLoc) [[]] ms
         go (Parens m) = go (unLoc m)
 

plugins/hls-class-plugin/src/Ide/Plugin/Class/ExactPrint.hs

@@ -13,10 +13,11 @@ import           Language.Haskell.GHC.ExactPrint
 import           Language.Haskell.GHC.ExactPrint.Parsers
 
 import           Data.Either.Extra                       (eitherToMaybe)
+import           Data.Functor.Identity                   (Identity)
 import           GHC.Parser.Annotation
+import           Language.LSP.Protocol.Types             (Range)
 
 makeEditText :: Monad m => ParsedModule -> DynFlags -> AddMinimalMethodsParams -> MaybeT m (T.Text, T.Text)
--- addMethodDecls :: ParsedSource -> [(LHsDecl GhcPs, LHsDecl GhcPs)] -> Range -> Bool -> TransformT Identity (Located HsModule)
 makeEditText pm df AddMinimalMethodsParams{..} = do
     mDecls <- MaybeT . pure $ traverse (makeMethodDecl df) methodGroup
     let ps = makeDeltaAst $ pm_parsed_source pm
@@ -31,14 +32,21 @@ makeMethodDecl df (mName, sig) = do
     sig' <- eitherToMaybe $ parseDecl df (T.unpack sig) $ T.unpack sig
     pure (name, sig')
 
+#if MIN_VERSION_ghc(9,5,0)
+addMethodDecls :: ParsedSource -> [(LHsDecl GhcPs, LHsDecl GhcPs)] -> Range -> Bool -> TransformT Identity (Located (HsModule GhcPs))
+#else
+addMethodDecls :: ParsedSource -> [(LHsDecl GhcPs, LHsDecl GhcPs)] -> Range -> Bool -> TransformT Identity (Located HsModule)
+#endif
 addMethodDecls ps mDecls range withSig
     | withSig = go (concatMap (\(decl, sig) -> [sig, decl]) mDecls)
     | otherwise = go (map fst mDecls)
     where
     go inserting = do
         allDecls <- hsDecls ps
-        let (before, ((L l inst): after)) = break (inRange range . getLoc) allDecls
-        replaceDecls ps (before ++ (L l (addWhere inst)): (map newLine inserting ++ after))
+        case break (inRange range . getLoc) allDecls of
+            (before, L l inst : after) -> replaceDecls ps (before ++ L l (addWhere inst):(map newLine inserting ++ after))
+            (before, []) -> replaceDecls ps before
+
     -- Add `where` keyword for `instance X where` if `where` is missing.
     --
     -- The `where` in ghc-9.2 is now stored in the instance declaration
@@ -48,15 +56,17 @@ addMethodDecls ps mDecls range withSig
     --
     -- See the link for the original definition:
     --   https://hackage.haskell.org/package/ghc-9.2.1/docs/Language-Haskell-Syntax-Extension.html#t:XCClsInstDecl
-    addWhere (InstD xInstD (ClsInstD ext decl@ClsInstDecl{..})) =
-        let (EpAnn entry anns comments, key) = cid_ext
-        in InstD xInstD (ClsInstD ext decl {
-        cid_ext = (EpAnn
-                    entry
-                    (AddEpAnn AnnWhere (EpaDelta (SameLine 1) []) : anns)
-                    comments
-                    , key)
-        })
+    addWhere instd@(InstD xInstD (ClsInstD ext decl@ClsInstDecl{..})) =
+        case cid_ext of
+            (EpAnn entry anns comments, key) ->
+                    InstD xInstD (ClsInstD ext decl {
+                    cid_ext = (EpAnn
+                                entry
+                                (AddEpAnn AnnWhere (EpaDelta (SameLine 1) []) : anns)
+                                comments
+                                , key)
+                    })
+            _ -> instd
     addWhere decl = decl
 
     newLine (L l e) =

plugins/hls-class-plugin/src/Ide/Plugin/Class/Types.hs

@@ -190,7 +190,6 @@ getInstanceBindLensRule recorder = do
                     (locA l) -- bindSpan
                     (locA l') -- bindNameSpan
             in toBindInfo <$> filter (\(L _ name) -> unLoc name `notElem` sigNames) bindNames
-        getBindSpanWithoutSig _ = []
 
         -- Get bind definition range with its rendered signature text
         getRangeWithSig :: Maybe (InstanceBindTypeSig, SrcSpan) -> IO (Maybe (Range, Int, Name, Type))