+withVirtualCWD :: GhcMonad m => m a -> m a
+withVirtualCWD m = do
+ hsc_env <- getSession
+ let ic = hsc_IC hsc_env
+
+ let set_cwd = do
+ dir <- liftIO $ getCurrentDirectory
+ case ic_cwd ic of
+ Just dir -> liftIO $ setCurrentDirectory dir
+ Nothing -> return ()
+ return dir
+
+ reset_cwd orig_dir = do
+ virt_dir <- liftIO $ getCurrentDirectory
+ hsc_env <- getSession
+ let old_IC = hsc_IC hsc_env
+ setSession hsc_env{ hsc_IC = old_IC{ ic_cwd = Just virt_dir } }
+ liftIO $ setCurrentDirectory orig_dir
+
+ gbracket set_cwd reset_cwd $ \_ -> m
+
+