From d2efb504b937738ecf3df27c835001f4e6e17d19 Mon Sep 17 00:00:00 2001
From: Julian Ospald <hasufell@posteo.de>
Date: Sun, 12 Apr 2020 18:54:03 +0200
Subject: [PATCH] Fix upgradeGHCup

File needs to be unlinked first, because it might
potentially be in use.
---
 lib/GHCup.hs | 11 ++++++++---
 1 file changed, 8 insertions(+), 3 deletions(-)

diff --git a/lib/GHCup.hs b/lib/GHCup.hs
index 7ed8075..dde8072 100644
--- a/lib/GHCup.hs
+++ b/lib/GHCup.hs
@@ -690,17 +690,22 @@ upgradeGHCup dls mtarget = do
   lift $ $(logInfo) [i|Upgrading GHCup...|]
   let latestVer = fromJust $ getLatest dls GHCup
   pfreq <- liftE platformRequest
-  dli <- lE $ getDownloadInfo GHCup latestVer pfreq dls
-  tmp <- lift withGHCupTmpDir
+  dli   <- lE $ getDownloadInfo GHCup latestVer pfreq dls
+  tmp   <- lift withGHCupTmpDir
   let fn = [rel|ghcup|]
   p <- liftE $ download dli tmp (Just fn)
   case mtarget of
     Nothing -> do
       dest <- liftIO $ ghcupBinDir
+      liftIO $ hideError NoSuchThing $ deleteFile (dest </> fn)
       handleIO (throwE . CopyError . show) $ liftIO $ copyFile p
                                                                (dest </> fn)
                                                                Overwrite
-    Just fullDest -> liftIO $ copyFile p fullDest Overwrite
+    Just fullDest -> do
+      liftIO $ hideError NoSuchThing $ deleteFile fullDest
+      handleIO (throwE . CopyError . show) $ liftIO $ copyFile p
+                                                               fullDest
+                                                               Overwrite
   pure latestVer