refactor getCurrentBranch

Both Command.Sync and Annex.Ingest had their own versions of this.

The one in Annex.Ingest used Git.Branch.currentUnsafe, but does not seem
to need it. That is only checking to see if it's in an adjusted unlocked
branch, and when in an adjusted branch, the branch does in fact exist,
so the added check that Git.Branch.current does is fine.

This commit was sponsored by Denis Dzyubenko on Patreon.

Command/Sync.hs

@@ -9,7 +9,6 @@
 module Command.Sync (
 	cmd,
 	CurrBranch,
-	getCurrBranch,
 	mergeConfig,
 	merge,
 	prepMerge,
@@ -60,6 +59,7 @@ import Annex.UpdateInstead
 import Annex.Export
 import Annex.LockFile
 import Annex.TaggedPush
+import Annex.CurrentBranch
 import qualified Database.Export as Export
 import Utility.Bloom
 import Utility.OptParse
@@ -162,8 +162,7 @@ seek :: SyncOptions -> CommandSeek
 seek o = allowConcurrentOutput $ do
 	prepMerge
 
-	getbranch <- getCurrBranch 
-	let withbranch a = a =<< getbranch
+	let withbranch a = a =<< getCurrentBranch
 
 	remotes <- syncRemotes (syncWith o)
 	let gitremotes = filter Remote.gitSyncableRemote remotes
@@ -188,7 +187,7 @@ seek o = allowConcurrentOutput $ do
 				]
 			
 			whenM shouldsynccontent $ do
-				syncedcontent <- seekSyncContent o dataremotes
+				syncedcontent <- withbranch $ seekSyncContent o dataremotes
 				exportedcontent <- withbranch $ seekExportContent exportremotes
 				-- Transferring content can take a while,
 				-- and other changes can be pushed to the
@@ -209,35 +208,6 @@ seek o = allowConcurrentOutput $ do
 		<||> pure (not (null (contentOfOption o)))
 		<||> (pure (not (noContentOption o)) <&&> getGitConfigVal annexSyncContent)
 
-type CurrBranch = (Maybe Git.Branch, Maybe Adjustment)
-
-{- There may not be a branch checked out until after the commit,
- - or perhaps after it gets merged from the remote, or perhaps
- - never.
- -
- - So only look it up once it's needed, and once there is a
- - branch, cache it.
- -
- - When on an adjusted branch, gets the original branch, and the adjustment.
- -}
-getCurrBranch :: Annex (Annex CurrBranch)
-getCurrBranch = do
-	mvar <- liftIO newEmptyMVar
-	return $ ifM (liftIO $ isEmptyMVar mvar)
-		( do
-			currbranch <- inRepo Git.Branch.current
-			case currbranch of
-				Nothing -> return (Nothing, Nothing)
-				Just b -> do
-					let v = case adjustedToOriginal b of
-						Nothing -> (Just b, Nothing)
-						Just (adj, origbranch) ->
-							(Just origbranch, Just adj)
-					liftIO $ putMVar mvar v
-					return v
-		, liftIO $ readMVar mvar
-		)
-
 {- Merging may delete the current directory, so go to the top
  - of the repo. This also means that sync always acts on all files in the
  - repository, not just on a subdirectory. -}
@@ -568,8 +538,11 @@ newer remote b = do
 		, return True
 		)
 
-{- Without --all, only looks at files in the work tree. With --all,
- - makes 2 passes, first looking at the work tree and then all keys.
+{- Without --all, only looks at files in the work tree.
+ - (Or, when in an ajusted branch where some files are hidden, at files in
+ - the original branch.)
+ -
+ - With --all, makes a second pass over all keys.
  - This ensures that preferred content expressions that match on
  - filenames work, even when in --all mode.
  -
@@ -577,15 +550,19 @@ newer remote b = do
  -
  - When concurrency is enabled, files are processed concurrently.
  -}
-seekSyncContent :: SyncOptions -> [Remote] -> Annex Bool
-seekSyncContent o rs = do
+seekSyncContent :: SyncOptions -> [Remote] -> CurrBranch -> Annex Bool
+seekSyncContent o rs currbranch = do
 	mvar <- liftIO newEmptyMVar
 	bloom <- case keyOptions o of
 		Just WantAllKeys -> Just <$> genBloomFilter (seekworktree mvar [])
-		_ -> do
-			l <- workTreeItems (contentOfOption o)
-			seekworktree mvar l (const noop)
-			pure Nothing
+		_ -> case currbranch of
+			(origbranch, Just adj) | adjustmentHidesFiles adj -> do
+				seekbranch origbranch (contentOfOption o)
+				pure Nohing
+			_ = do
+				l <- workTreeItems (contentOfOption o)
+				seekworktree mvar l (const noop)
+				pure Nothing
 	withKeyOptions' (keyOptions o) False
 		(return (seekkeys mvar bloom))
 		(const noop)
@@ -595,7 +572,11 @@ seekSyncContent o rs = do
   where
 	seekworktree mvar l bloomfeeder = seekHelper LsFiles.inRepo l >>=
 		mapM_ (\f -> ifAnnexed f (go (Right bloomfeeder) mvar (AssociatedFile (Just f))) noop)
+
+	seekbranch origbranch l = 
+
 	seekkeys mvar bloom (k, _) = go (Left bloom) mvar (AssociatedFile Nothing) k
+
 	go ebloom mvar af k = commandAction $ do
 		whenM (syncFile ebloom rs af k) $
 			void $ liftIO $ tryPutMVar mvar ()