From 267edfebe3a3e14d363213fe3ace290f34de4705 Mon Sep 17 00:00:00 2001
From: Nikolay Yakimov <root@livid.pp.ru>
Date: Fri, 3 Jul 2015 19:35:22 +0300
Subject: [PATCH] Try best-guess tactic if file to be redirected doesn't exist

---
 Language/Haskell/GhcMod/FileMapping.hs | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/Language/Haskell/GhcMod/FileMapping.hs b/Language/Haskell/GhcMod/FileMapping.hs
index 8904efa..93f7cb1 100644
--- a/Language/Haskell/GhcMod/FileMapping.hs
+++ b/Language/Haskell/GhcMod/FileMapping.hs
@@ -52,7 +52,10 @@ getCanonicalFileName :: IOish m => FilePath -> GhcModT m FilePath
 getCanonicalFileName fn = do
   crdl <- cradle
   let ccfn = cradleCurrentDir crdl </> fn
-  liftIO $ canonicalizePath ccfn
+  fex <- liftIO $ doesFileExist ccfn
+  if fex
+    then liftIO $ canonicalizePath ccfn
+    else return ccfn
 
 unloadMappedFile :: IOish m => FilePath -> GhcModT m ()
 unloadMappedFile = (delMMappedFile =<<) . getCanonicalFileName