From 5df1fb660c0cb3a41e18e21802e482e7ea75fb7a Mon Sep 17 00:00:00 2001
From: Christopher Vollick <0@psycoti.ca>
Date: Fri, 8 Jan 2021 12:01:38 -0500
Subject: [PATCH] Replace Non-Exhaustive Pattern with Case

I did this because in newer versions of GHC things like this require a
MonadFail instance, whereas explicitly handling it like this does not.

Now, we don't currently require those newer versions, but since I happened to
have a new one it was causing me trouble. And this new way works in both
versions, so I think it's safe to just throw it in here.
---
 StoreChunks.hs | 11 ++++++-----
 1 file changed, 6 insertions(+), 5 deletions(-)

diff --git a/StoreChunks.hs b/StoreChunks.hs
index e395c1c..359feb1 100644
--- a/StoreChunks.hs
+++ b/StoreChunks.hs
@@ -34,11 +34,12 @@ storeChunks storePath tmpName getChunk = loop hashInit hashInit hashInit
 	tmpPath = storePath ++ "/tmp/" ++ tmpName
 	cidPath digest = storePath ++ "/" ++ textToString (digestCID digest)
 	loop sha1 sha256 sha512 = do
-			Just chunk <- UIO.lift getChunk
-			if ByteString.null chunk then
-				finish sha1 sha256 sha512
-			else
-				step sha1 sha256 sha512 chunk
+		maybeChunk <- UIO.lift getChunk
+		case maybeChunk of
+			Nothing -> return $ Left $ userError "Failed to getChunk"
+			Just chunk
+				| ByteString.null chunk -> finish sha1 sha256 sha512
+				| otherwise -> step sha1 sha256 sha512 chunk
 
 	step sha1 sha256 sha512 chunk = do
 		result <- UIO.fromIO' (error.show) $ do
-- 
2.34.2