oldkeys: check associated files by default and add --unchecked

Removed the prior code that checked for keys used by current versions of
the files being acted on. It is redundant with the associated files
check (so long as the associated files database is always up-to-date,
which reconcileStaged should accomplish).

Sponsored-by: Luke T. Shumaker on Patreon

Command/OldKeys.hs

@@ -1,4 +1,4 @@
-{- GIT-annex command
+{- git-annex command
  -
  - Copyright 2023 Joey Hess <id@joeyh.name>
  -
@@ -16,13 +16,12 @@ import qualified Annex
 import Annex.CatFile
 import Utility.Terminal
 import qualified Utility.Format
+import qualified Database.Keys
 
-import qualified Data.Map as M
-import qualified Data.Set as S
 import qualified Data.ByteString.Char8 as S8
 
 cmd :: Command
-cmd = noCommit $ withAnnexOptions [annexedMatchingOptions] $
+cmd = noCommit $
 	command "oldkeys" SectionQuery
 		"list keys used for old versions of files"
 		paramPaths (seek <$$> optParser)
@@ -30,6 +29,7 @@ cmd = noCommit $ withAnnexOptions [annexedMatchingOptions] $
 data OldKeysOptions = OldKeysOptions
 	{ fileOptions :: CmdParams
 	, revisionRange :: Maybe String
+	, uncheckedOption :: Bool
 	}
 
 optParser :: CmdParamsDesc -> Parser OldKeysOptions
@@ -39,20 +39,21 @@ optParser desc = OldKeysOptions
 		( long "revision-range" <> metavar "RANGE"
 		<> help "limit to a revision range"
 		))
+	<*> switch 
+		( long "unchecked"
+		<> help "don't check if current files use keys"
+		)
 
 seek :: OldKeysOptions -> CommandSeek
 seek o = do
 	isterminal <- liftIO $ checkIsTerminal stdout
-	-- Get the diff twice and make separate passes over it
-	-- to avoid needing to cache it all in memory.
-	currentkeys <- withdiff getcurrentkeys
 	withdiff $ \l -> 
 		forM_ l $ \i ->
 			when (DiffTree.srcsha i `notElem` nullShas) $ do
 				catKey (DiffTree.srcsha i) >>= \case
-					Just key | S.notMember key currentkeys ->
-						commandAction $ start isterminal key
-					_ -> return ()
+					Just key -> commandAction $ 
+						start o isterminal key
+					Nothing -> return ()
   where
   	withdiff a = do
 		(output, cleanup) <- Annex.inRepo $
@@ -87,38 +88,17 @@ seek o = do
 		Just TreeExecutable -> True
 		Just TreeSymlink -> True
 		_ -> False
-	
-	-- Accumulate the most recent key used for each file 
-	-- (that is not deleted).
-	-- Those keys should never be listed as old keys, even if
-	-- some other file did have them as an old key. This avoids
-	-- surprising behavior for renames and reverts.
-	getcurrentkeys l = getcurrentkeys' l M.empty
-	getcurrentkeys' [] m = pure $ S.fromList $ catMaybes $ M.elems m
-	getcurrentkeys' (i:l) m
-		| not (isfilemode (DiffTree.dstmode i)) =
-			getcurrentkeys' l m
-		| DiffTree.dstsha i `elem` nullShas = 
-			getcurrentkeys' l $
-				M.insertWith (\_ prev -> prev)
-					(DiffTree.file i)
-					Nothing
-					m
-		| otherwise = case M.lookup (DiffTree.file i) m of
-			Just _ -> getcurrentkeys' l m
-			Nothing -> catKey (DiffTree.dstsha i) >>= \case
-				Just key -> getcurrentkeys' l $
-					M.insert	
-						(DiffTree.file i)
-						(Just key)
-						m
-				_ -> getcurrentkeys' l m
 
-start :: IsTerminal -> Key -> CommandStart
-start (IsTerminal isterminal) key = startingCustomOutput key $ do
-	liftIO $ S8.putStrLn $ if isterminal
-		then Utility.Format.encode_c (const False) sk
-		else sk
-	next $ return True
+start :: OldKeysOptions -> IsTerminal -> Key -> CommandStart
+start o (IsTerminal isterminal) key
+	| uncheckedOption o = go
+	| otherwise = Database.Keys.getAssociatedFiles key >>= \case
+		[] -> go
+		_ -> stop
   where
+	go = startingCustomOutput key $ do
+		liftIO $ S8.putStrLn $ if isterminal
+			then Utility.Format.encode_c (const False) sk
+			else sk
+		next $ return True
 	sk = serializeKey' key

doc/git-annex-oldkeys.mdwn

@@ -15,14 +15,21 @@ The output from this command can be piped into a command like
 
 The keys are listed in order from newest to oldest.
 
-When listing old keys for a directory, it will include the most recent
-key used by deleted files (but not by renamed files).
-
-Note that the listed keys may still be used by other files in the
-repository.
+When listing old keys for a directory, it will include keys used by deleted
+files that were in that directory in past commits.
 
 # OPTIONS
 
+* --unchecked
+
+  By default this command does not list a key that is also used by any
+  file in the currently checked out branch. This option makes it also
+  list such keys.
+
+  The default behavior avoids surprises when dropping listed keys.
+  This option can be useful when eg copying all old versions of a file to a
+  remote.
+
 * --revision-range=value
 
   Only list old keys used in the specified range of revisions.