sync, pre-commit, indirect: Avoid unnecessarily catting non-symlink files from git, which can be so large it runs out of memory.

Annex/Direct.hs

@@ -14,8 +14,8 @@ import qualified Git.Merge
 import qualified Git.DiffTree as DiffTree
 import Git.Sha
 import Git.Types
-import Annex.CatFile
 import Git.FileMode
+import Annex.CatFile
 import qualified Annex.Queue
 import Logs.Location
 import Backend
@@ -45,8 +45,10 @@ stageDirect = do
 	{- Determine what kind of modified or deleted file this is, as
 	 - efficiently as we can, by getting any key that's associated
 	 - with it in git, as well as its stat info. -}
-	go (file, Just sha) = do
-		shakey <- catKey sha
+	go (file, Just sha, Just mode) = do
+		shakey <- if isSymLink mode
+			then catKey sha
+			else return Nothing
 		mstat <- liftIO $ catchMaybeIO $ getSymbolicLinkStatus file
 		filekey <- isAnnexLink file
 		case (shakey, filekey, mstat, toInodeCache =<< mstat) of