From b547324253184c41279d5e6c312a7f01f0106f8e Mon Sep 17 00:00:00 2001
From: Julian Ospald <hasufell@posteo.de>
Date: Thu, 23 Feb 2023 21:47:50 +0800
Subject: [PATCH] Smarter variants for 'listDirectory', fixing #797

---
 lib/GHCup/Utils.hs      | 12 ++++++------
 lib/GHCup/Utils/Dirs.hs | 27 ++++++++++++++++++++++++++-
 2 files changed, 32 insertions(+), 7 deletions(-)

diff --git a/lib/GHCup/Utils.hs b/lib/GHCup/Utils.hs
index 37c109c..4a78b62 100644
--- a/lib/GHCup/Utils.hs
+++ b/lib/GHCup/Utils.hs
@@ -335,7 +335,7 @@ ghcSet mtarget = do
 getInstalledGHCs :: (MonadReader env m, HasDirs env, MonadIO m) => m [Either FilePath GHCTargetVersion]
 getInstalledGHCs = do
   ghcdir <- ghcupGHCBaseDir
-  fs     <- liftIO $ hideErrorDef [NoSuchThing] [] $ listDirectory (fromGHCupPath ghcdir)
+  fs     <- liftIO $ hideErrorDef [NoSuchThing] [] $ listDirectoryDirs (fromGHCupPath ghcdir)
   forM fs $ \f -> case parseGHCupGHCDir f of
     Right r -> pure $ Right r
     Left  _ -> pure $ Left f
@@ -438,7 +438,7 @@ getInstalledHLSs = do
         Nothing        -> pure $ Left f
 
   hlsdir <- ghcupHLSBaseDir
-  fs     <- liftIO $ hideErrorDef [NoSuchThing] [] $ listDirectory (fromGHCupPath hlsdir)
+  fs     <- liftIO $ hideErrorDef [NoSuchThing] [] $ listDirectoryDirs (fromGHCupPath hlsdir)
   new <- forM fs $ \f -> case parseGHCupHLSDir f of
     Right r -> pure $ Right r
     Left  _ -> pure $ Left f
@@ -626,7 +626,7 @@ hlsInternalServerScripts ver mghcVer = do
   dir <- ghcupHLSDir ver
   let bdir = fromGHCupPath dir </> "bin"
   fmap (bdir </>) . filter (\f -> maybe True (\gv -> ("-" <> T.unpack (prettyVer gv)) `isSuffixOf` f) mghcVer)
-    <$> liftIO (listDirectory bdir)
+    <$> liftIO (listDirectoryFiles bdir)
 
 -- | Get all binaries for a hls version from the ~/.ghcup/hls/<ver>/lib/haskell-language-server-<ver>/bin directory, if any.
 -- Returns the full path.
@@ -639,7 +639,7 @@ hlsInternalServerBinaries ver mghcVer = do
   let regex = makeRegexOpts compExtended execBlank ([s|^haskell-language-server-.*$|] :: ByteString)
   (Just bdir) <- fmap headMay $ liftIO $ expandFilePath [Left (dir </> "lib"), Right regex, Left "bin"]
   fmap (bdir </>) . filter (\f -> maybe True (\gv -> ("-" <> T.unpack (prettyVer gv)) `isSuffixOf` f) mghcVer)
-    <$> liftIO (listDirectory bdir)
+    <$> liftIO (listDirectoryFiles bdir)
 
 -- | Get all libraries for a hls version from the ~/.ghcup/hls/<ver>/lib/haskell-language-server-<ver>/lib/<ghc-ver>/
 -- directory, if any.
@@ -652,7 +652,7 @@ hlsInternalServerLibs ver ghcVer = do
   dir <- fromGHCupPath <$> ghcupHLSDir ver
   let regex = makeRegexOpts compExtended execBlank ([s|^haskell-language-server-.*$|] :: ByteString)
   (Just bdir) <- fmap headMay $ liftIO $ expandFilePath [Left (dir </> "lib"), Right regex, Left ("lib" </> T.unpack (prettyVer ghcVer))]
-  fmap (bdir </>) <$> liftIO (listDirectory bdir)
+  fmap (bdir </>) <$> liftIO (listDirectoryFiles bdir)
 
 
 -- | Get the wrapper binary for an hls version, if any.
@@ -936,7 +936,7 @@ ghcToolFiles ver = do
   whenM (fmap not $ ghcInstalled ver)
         (throwE (NotInstalled GHC ver))
 
-  files <- liftIO (listDirectory bindir >>= filterM (doesFileExist . (bindir </>)))
+  files <- liftIO (listDirectoryFiles bindir >>= filterM (doesFileExist . (bindir </>)))
   pure (getUniqueTools . groupToolFiles . fmap (dropSuffix exeExt) $ files)
 
  where
diff --git a/lib/GHCup/Utils/Dirs.hs b/lib/GHCup/Utils/Dirs.hs
index 4f791cf..dc8ebb0 100644
--- a/lib/GHCup/Utils/Dirs.hs
+++ b/lib/GHCup/Utils/Dirs.hs
@@ -42,6 +42,9 @@ module GHCup.Utils.Dirs
   , removeDirectoryRecursive
   , removePathForcibly
 
+  , listDirectoryFiles
+  , listDirectoryDirs
+
   -- System.Directory re-exports
   , createDirectory
   , createDirectoryIfMissing
@@ -130,7 +133,7 @@ import           Data.Maybe
 import           Data.Versions
 import           GHC.IO.Exception               ( IOErrorType(NoSuchThing) )
 import           Haskus.Utils.Variant.Excepts
-import           Optics
+import           Optics hiding ( uncons )
 import           Safe
 import           System.Directory hiding ( removeDirectory
                                          , removeDirectoryRecursive
@@ -529,6 +532,28 @@ cleanupTrash = do
       ) $ liftIO $ removePathForcibly (recycleDir `appendGHCupPath` fp))
 
 
+-- | List *actual files* in a directory, ignoring empty files and a couple
+-- of blacklisted files, such as '.DS_Store' on mac.
+listDirectoryFiles :: FilePath -> IO [FilePath]
+listDirectoryFiles fp = do
+  listDirectory fp >>= filterM (doesFileExist . (fp </>)) <&> filter (\fp' -> not (isHidden fp') && not (isBlacklisted fp'))
+
+-- | List *actual directories* in a directory, ignoring empty directories and a couple
+-- of blacklisted files, such as '.DS_Store' on mac.
+listDirectoryDirs :: FilePath -> IO [FilePath]
+listDirectoryDirs fp = do
+  listDirectory fp >>= filterM (doesDirectoryExist . (fp </>)) <&> filter (\fp' -> not (isHidden fp') && not (isBlacklisted fp'))
+
+isHidden :: FilePath -> Bool
+isHidden fp'
+  | isWindows = False
+  | Just ('.', _) <- uncons fp' = True
+  | otherwise = False
+
+isBlacklisted :: FilePath -> Bool
+isBlacklisted fp' = fp' `elem` [".DS_Store"]
+
+
 
 -- System.Directory re-exports with GHCupPath