Case-insensitive readme file extension check

It is not uncommon to have README.TXT files.

Author: wismill

src/Distribution/Server/Packages/Readme.hs

@@ -6,9 +6,9 @@ import System.FilePath (splitExtension)
 import Data.Char as Char
 
 isReadmeFile :: FilePath -> Bool
-isReadmeFile fname = map Char.toLower base `elem` basenames
-                        && ext `elem` extensions
+isReadmeFile fname = base `elem` basenames
+                     && ext `elem` extensions
   where
-    (base, ext) = splitExtension fname
+    (base, ext) = splitExtension (map Char.toLower fname)
     basenames  = ["readme"]
     extensions = ["", ".txt", ".html", ".md", ".markdown"]