unused: --used-refspec can now be configured to look at refs in the reflog. This provides a way to not consider old versions of files to be unused after they have reached a specified age, when the old refs in the reflog expire.

May be slow.

Annex/Branch.hs

@@ -210,7 +210,7 @@ getHistorical :: RefDate -> FilePath -> Annex String
 getHistorical date file =
 	-- This check avoids some ugly error messages when the reflog
 	-- is empty.
-	ifM (null <$> inRepo (Git.RefLog.get' [Param "-n1"] fullname))
+	ifM (null <$> inRepo (Git.RefLog.get' [Param "-n1"] (Just fullname)))
 		( error ("No reflog for " ++ fromRef fullname)
 		, getRef (Git.Ref.dateRef fullname date) file
 		)

Command/Unused.hs

@@ -21,6 +21,7 @@ import qualified Git
 import qualified Git.Command
 import qualified Git.Ref
 import qualified Git.Branch
+import qualified Git.RefLog
 import qualified Git.LsFiles as LsFiles
 import qualified Git.DiffTree as DiffTree
 import qualified Backend
@@ -216,8 +217,9 @@ withKeysReferencedInGit :: RefSpec -> (Key -> Annex ()) -> Annex ()
 withKeysReferencedInGit refspec a = do
 	current <- inRepo Git.Branch.currentUnsafe
 	shaHead <- maybe (return Nothing) (inRepo . Git.Ref.sha) current
-	usedrefs <- applyRefSpec refspec . relevantrefs (shaHead, current)
+	rs <- relevantrefs (shaHead, current)
 		<$> inRepo (Git.Command.pipeReadStrict [Param "show-ref"])
+	usedrefs <- applyRefSpec refspec rs (inRepo Git.RefLog.getAll)
 	forM_ usedrefs $
 		withKeysReferencedInGitRef a
   where

Git/RefLog.hs

@@ -14,14 +14,18 @@ import Git.Sha
 
 {- Gets the reflog for a given branch. -}
 get :: Branch -> Repo -> IO [Sha]
-get = get' []
+get b = get' [] (Just b)
 
-get' :: [CommandParam] -> Branch -> Repo -> IO [Sha]
+{- Gets all reflogs for all branches. -}
+getAll :: Repo -> IO [Sha]
+getAll = get' [Param "--all"] Nothing
+
+get' :: [CommandParam] -> Maybe Branch -> Repo -> IO [Sha]
 get' ps b = mapMaybe extractSha . lines <$$> pipeReadStrict ps'
   where
-	ps' = 
-		[ Param "log"
-		, Param "-g"
-		, Param "--format=%H"
-		, Param (fromRef b)
+	ps' = catMaybes
+		[ Just $ Param "log"
+		, Just $ Param "-g"
+		, Just $ Param "--format=%H"
+		, Param . fromRef <$> b
 		] ++ ps

Types/RefSpec.hs

@@ -15,7 +15,11 @@ import Data.Either
 
 type RefSpec = [RefSpecPart]
 
-data RefSpecPart = AddRef Ref | AddMatching Glob | RemoveMatching Glob
+data RefSpecPart
+	= AddRef Ref
+	| AddMatching Glob
+	| AddRefLog
+	| RemoveMatching Glob
 
 allRefSpec :: RefSpec
 allRefSpec = [AddMatching $ compileGlob "*" CaseSensative]
@@ -30,15 +34,19 @@ parseRefSpec v = case partitionEithers (map mk $ split ":" v) of
 			Right $ AddMatching $ compileGlob s CaseSensative
 		| otherwise = Right $ AddRef $ Ref s
 	mk ('-':s) = Right $ RemoveMatching $ compileGlob s CaseSensative
+	mk "reflog" = Right AddRefLog
 	mk s = Left $ "bad refspec item \"" ++ s ++ "\" (expected + or - prefix)"
 
-applyRefSpec :: RefSpec -> [Ref] -> [Ref]
-applyRefSpec refspec rs = go [] refspec
+applyRefSpec :: Monad m => RefSpec -> [Ref] -> m [Sha] -> m [Ref]
+applyRefSpec refspec rs getreflog = go [] refspec
   where
-	go c [] = reverse c
+	go c [] = return (reverse c)
 	go c (AddRef r : rest) = go (r:c) rest
 	go c (AddMatching g : rest) =
 		let add = filter (matchGlob g . fromRef) rs
 		in go (add ++ c) rest
+	go c (AddRefLog : rest) = do
+		reflog <- getreflog
+		go (reflog ++ c) rest
 	go c (RemoveMatching g : rest) = 
 		go (filter (not . matchGlob g . fromRef) c) rest

debian/changelog

@@ -27,6 +27,10 @@ git-annex (5.20150618) UNRELEASED; urgency=medium
     link to annexed content.
   * sync: When annex.autocommit=false, avoid making any commit of local
     changes, while still merging with remote to the extent possible.
+  * unused: --used-refspec can now be configured to look at refs in the
+    reflog. This provides a way to not consider old versions of files to be
+    unused after they have reached a specified age, when the old refs in
+    the reflog expire.
 
  -- Joey Hess <id@joeyh.name>  Thu, 02 Jul 2015 12:31:14 -0400
 

doc/git-annex-unused.mdwn

@@ -60,6 +60,11 @@ and walking the list in order from left to right.
   For example, "+HEAD^" adds "HEAD^".
 * Each - is matched against the set of refs accumulated so far.
   Any matching refs are removed from the set.
+* "reflog" adds all the refs from the reflog. This will make past versions
+  of files not be considered to be unused until the ref expires from the
+  reflog (by default for 90 days). Note that this may make git-annex unused
+  take some time to complete, it if needs to check every ref from the
+  reflog.
 
 # SEE ALSO
 

doc/todo/Deleting_Unused_Files_by_Age.mdwn

@@ -11,3 +11,7 @@ I would like to not drop all unused files.
 > However, I think that many users expect git annex unused to be able to
 > immediately find and remove a file after it's been deleted. So this
 > probably needs to be a configurable behavior. --[[Joey]]
+
+>> Implemented this,  `git annex unused --used-refspec=+refs/heads/*:reflog`
+>> will consider all head refs as used (the default), plus consider all
+>> refs in the reflog as used. [[done]] --[[Joey]]