direct mode mappings now updated by git annex sync

Still lots to do to make sync handle direct mode, but this is a good first
step.

Command/Sync.hs

@@ -15,6 +15,7 @@ import qualified Annex
 import qualified Annex.Branch
 import qualified Annex.Queue
 import Annex.Content
+import Annex.Content.Direct
 import Annex.CatFile
 import qualified Git.Command
 import qualified Git.LsFiles as LsFiles
@@ -129,19 +130,39 @@ pullRemote remote branch = do
 {- The remote probably has both a master and a synced/master branch.
  - Which to merge from? Well, the master has whatever latest changes
  - were committed, while the synced/master may have changes that some
- - other remote synced to this remote. So, merge them both. -}
+ - other remote synced to this remote. So, merge them both.
+ -
+ - In direct mode, updates associated files mappings for the files that
+ - were changed by the merge.
+ -}
 mergeRemote :: Remote -> (Maybe Git.Ref) -> CommandCleanup
 mergeRemote remote b = case b of
 	Nothing -> do
 		branch <- inRepo Git.Branch.currentUnsafe
-		all id <$> (mapM merge $ branchlist branch)
-	Just _ -> all id <$> (mapM merge =<< tomerge (branchlist b))
+		update branch $
+			all id <$> (mapM merge $ branchlist branch)
+	Just branch -> update (Just branch) $
+		all id <$> (mapM merge =<< tomerge (branchlist b))
   where
 	merge = mergeFrom . remoteBranch remote
 	tomerge branches = filterM (changed remote) branches
 	branchlist Nothing = []
 	branchlist (Just branch) = [branch, syncBranch branch]
 
+	update Nothing a = a
+	update (Just branch) a = ifM isDirect
+		( do
+			old <- inRepo $ Git.Ref.sha branch
+			r <- a
+			new <- inRepo $ Git.Ref.sha branch
+			case (old, new) of
+				(Just oldsha, Just newsha) -> do
+					updateAssociatedFiles oldsha newsha
+				_ -> noop
+			return r
+		, a
+		)
+
 pushRemote :: Remote -> Git.Ref -> CommandStart
 pushRemote remote branch = go =<< needpush
   where