added guardAgainstHpack function

Revert "added guardAgainstHpack function"

This reverts commit f7fb00c.

added guardAgainstHpack function

Author: JMoss-dev

plugins/hls-cabal-plugin/src/Ide/Plugin/Cabal/CabalAdd.hs

@@ -277,7 +277,7 @@ getDependencyEdit recorder env cabalFilePath buildTarget dependency = do
       logWith recorder Debug $ LogCreatedEdit edit
       pure edit
 
--- | Given a path to a haskell file, returns the closest cabal file.
+-- | Given a path to a haskell file, returns the closest cabal file, except if package.yaml is also present.
 --   If cabal file wasn't found, gives Nothing.
 findResponsibleCabalFile :: FilePath -> IO (Maybe FilePath)
 findResponsibleCabalFile haskellFilePath = do
@@ -293,7 +293,12 @@ findResponsibleCabalFile haskellFilePath = do
       cabalFiles <- filterM (\c -> doesFileExist c) objectsCabalExtension
       case safeHead cabalFiles of
         Nothing        -> go ps
-        Just cabalFile -> pure $ Just cabalFile
+        Just cabalFile -> guardAgainstHpack path cabalFile
+          where
+            guardAgainstHpack :: FilePath -> FilePath -> IO (Maybe FilePath)
+            guardAgainstHpack path cabalFile = do
+              exists <- doesFileExist $ path </> "package.yaml"
+              if exists then pure Nothing else pure $ Just cabalFile
 
 -- | Gives cabal file's contents or throws error.
 --   Inspired by @readCabalFile@ in cabal-add,