Don't clean up tmp dirs when --keep=always

lib/GHCup/Utils/Dirs.hs

@@ -465,13 +465,20 @@ withGHCupTmpDir :: ( MonadReader env m
                    , MonadMask m
                    , MonadIO m)
                 => m GHCupPath
-withGHCupTmpDir = snd <$> withRunInIO (\run ->
+withGHCupTmpDir = do
+  Settings{keepDirs} <- getSettings
+  snd <$> withRunInIO (\run ->
     run
       $ allocate
           (run mkGhcupTmpDir)
-        (\fp ->
-            handleIO (\e -> run
-                $ logDebug ("Resource cleanup failed for " <> T.pack (fromGHCupPath fp) <> ", error was: " <> T.pack (displayException e)))
+          (\fp -> if -- we don't know whether there was a failure, so can only
+                     -- decide for 'Always'
+                     | keepDirs == Always -> pure ()
+                     | otherwise -> handleIO (\e -> run
+                        $ logDebug ("Resource cleanup failed for "
+                                   <> T.pack (fromGHCupPath fp)
+                                   <> ", error was: "
+                                   <> T.pack (displayException e)))
                         . removePathForcibly
                         $ fp))