Implement git history log in repo page

src/Data/ByteString/Char8/Local.hs

@@ -0,0 +1,28 @@
+{- This file is part of Vervis.
+ -
+ - Written in 2016 by fr33domlover <fr33domlover@riseup.net>.
+ -
+ - ♡ Copying is an act of love. Please copy, reuse and share.
+ -
+ - The author(s) have dedicated all copyright and related and neighboring
+ - rights to this software to the public domain worldwide. This software is
+ - distributed without any warranty.
+ -
+ - You should have received a copy of the CC0 Public Domain Dedication along
+ - with this software. If not, see
+ - <http://creativecommons.org/publicdomain/zero/1.0/>.
+ -}
+
+module Data.ByteString.Char8.Local
+    ( takeLine
+    )
+where
+
+import Prelude hiding (takeWhile)
+
+import Data.ByteString.Char8
+
+import Data.Char.Local (isNewline)
+
+takeLine :: ByteString -> ByteString
+takeLine = takeWhile $ not . isNewline

src/Data/Char/Local.hs

@@ -15,6 +15,7 @@
 
 module Data.Char.Local
     ( isAsciiLetter
+    , isNewline
     )
 where
 
@@ -22,3 +23,6 @@ import Prelude
 
 isAsciiLetter :: Char -> Bool
 isAsciiLetter c = 'A' <= c && c <= 'Z' || 'a' <= c && c <= 'z'
+
+isNewline :: Char -> Bool
+isNewline c = c == '\n' || c == '\r'

src/Data/Git/Local.hs

@@ -154,7 +154,7 @@ loadCommitGraphByName :: Graph g => Git -> String -> IO (CommitGraph g)
 loadCommitGraphByName git name = do
     mg <- loadCommitGraphByNameMaybe git name
     case mg of
-        Nothing -> error ""
+        Nothing -> error "no such ref"
         Just g  -> return g
 
 -- | Load a commit graph and topsort the commits. The resulting list starts