reorder repo parameters last

Many functions took the repo as their first parameter. Changing it
consistently to be the last parameter allows doing some useful things with
currying, that reduce boilerplate.

In particular, g <- gitRepo is almost never needed now, instead
use inRepo to run an IO action in the repo, and fromRepo to get
a value from the repo.

This also provides more opportunities to use monadic and applicative
combinators.

Command/Add.hs

@@ -60,8 +60,8 @@ undo file key e = do
 		-- fromAnnex could fail if the file ownership is weird
 		tryharder :: IOException -> Annex ()
 		tryharder _ = do
-			g <- gitRepo
-			liftIO $ renameFile (gitAnnexLocation g key) file
+			src <- fromRepo $ gitAnnexLocation key
+			liftIO $ renameFile src file
 
 cleanup :: FilePath -> Key -> Bool -> CommandCleanup
 cleanup file key hascontent = do

Command/AddUrl.hs

@@ -41,10 +41,9 @@ perform url file = do
 
 download :: String -> FilePath -> CommandPerform
 download url file = do
-	g <- gitRepo
 	showAction $ "downloading " ++ url ++ " "
 	let dummykey = Backend.URL.fromUrl url
-	let tmp = gitAnnexTmpLocation g dummykey
+	tmp <- fromRepo $ gitAnnexTmpLocation dummykey
 	liftIO $ createDirectoryIfMissing True (parentDir tmp)
 	ok <- liftIO $ Url.download url tmp
 	if ok

Command/DropUnused.hs

@@ -58,17 +58,15 @@ perform key = maybe droplocal dropremote =<< Annex.getState Annex.fromremote
 			next $ Command.Drop.cleanupRemote key r
 		droplocal = Command.Drop.performLocal key (Just 0) -- force drop
 
-performOther :: (Git.Repo -> Key -> FilePath) -> Key -> CommandPerform
+performOther :: (Key -> Git.Repo -> FilePath) -> Key -> CommandPerform
 performOther filespec key = do
-	g <- gitRepo
-	let f = filespec g key
+	f <- fromRepo $ filespec key
 	liftIO $ whenM (doesFileExist f) $ removeFile f
 	next $ return True
 
 readUnusedLog :: FilePath -> Annex UnusedMap
 readUnusedLog prefix = do
-	g <- gitRepo
-	let f = gitAnnexUnusedLog prefix g
+	f <- fromRepo $ gitAnnexUnusedLog prefix
 	e <- liftIO $ doesFileExist f
 	if e
 		then M.fromList . map parse . lines <$> liftIO (readFile f)

Command/Fsck.hs

@@ -79,26 +79,26 @@ check = sequence >=> dispatch
    in this repository only. -}
 verifyLocationLog :: Key -> String -> Annex Bool
 verifyLocationLog key desc = do
-	g <- gitRepo
 	present <- inAnnex key
 	
 	-- Since we're checking that a key's file is present, throw
 	-- in a permission fixup here too.
-	when present $ liftIO $ do
-		let f = gitAnnexLocation g key
-		preventWrite f
-		preventWrite (parentDir f)
+	when present $ do
+		f <- fromRepo $ gitAnnexLocation key
+		liftIO $ do
+			preventWrite f
+			preventWrite (parentDir f)
 
 	u <- getUUID
         uuids <- keyLocations key
 
 	case (present, u `elem` uuids) of
 		(True, False) -> do
-				fix g u InfoPresent
+				fix u InfoPresent
 				-- There is no data loss, so do not fail.
 				return True
 		(False, True) -> do
-				fix g u InfoMissing
+				fix u InfoMissing
 				warning $
 					"** Based on the location log, " ++ desc
 					++ "\n** was expected to be present, " ++
@@ -107,16 +107,16 @@ verifyLocationLog key desc = do
 		_ -> return True
 	
 	where
-		fix g u s = do
+		fix u s = do
 			showNote "fixing location log"
+			g <- gitRepo
 			logChange g key u s
 
 {- The size of the data for a key is checked against the size encoded in
  - the key's metadata, if available. -}
 checkKeySize :: Key -> Annex Bool
 checkKeySize key = do
-	g <- gitRepo
-	let file = gitAnnexLocation g key
+	file <- fromRepo $ gitAnnexLocation key
 	present <- liftIO $ doesFileExist file
 	case (present, Types.Key.keySize key) of
 		(_, Nothing) -> return True

Command/Map.hs

@@ -31,8 +31,7 @@ seek = [withNothing start]
 
 start :: CommandStart
 start = do
-	g <- gitRepo
-	rs <- spider g
+	rs <- spider =<< gitRepo
 
 	umap <- uuidMap
 	trusted <- trustGet Trusted

Command/Migrate.hs

@@ -42,14 +42,13 @@ upgradableKey key = isNothing $ Types.Key.keySize key
 
 perform :: FilePath -> Key -> Backend Annex -> CommandPerform
 perform file oldkey newbackend = do
-	g <- gitRepo
-
 	-- Store the old backend's cached key in the new backend
 	-- (the file can't be stored as usual, because it's already a symlink).
 	-- The old backend's key is not dropped from it, because there may
 	-- be other files still pointing at that key.
-	let src = gitAnnexLocation g oldkey
-	let tmpfile = gitAnnexTmpDir g </> takeFileName file
+	src <- fromRepo $ gitAnnexLocation oldkey
+	tmp <- fromRepo $ gitAnnexTmpDir
+	let tmpfile = tmp </> takeFileName file
 	liftIO $ createLink src tmpfile
 	k <- Backend.genKey tmpfile $ Just newbackend
 	liftIO $ cleantmp tmpfile

Command/SendKey.hs

@@ -21,8 +21,7 @@ seek = [withKeys start]
 
 start :: Key -> CommandStart
 start key = do
-	g <- gitRepo
-	let file = gitAnnexLocation g key
+	file <- fromRepo $ gitAnnexLocation key
 	whenM (inAnnex key) $
 		liftIO $ rsyncServerSend file -- does not return
 	warning "requested key is not present"

Command/Unannex.hs

@@ -31,8 +31,8 @@ start file = isAnnexed file $ \(key, _) -> do
 		then do
 			force <- Annex.getState Annex.force
 			unless force $ do
-				g <- gitRepo
-				staged <- liftIO $ LsFiles.staged g [Git.workTree g]
+				top <- fromRepo Git.workTree
+				staged <- inRepo $ LsFiles.staged [top]
 				unless (null staged) $
 					error "This command cannot be run when there are already files staged for commit."
 				Annex.changeState $ \s -> s { Annex.force = True }
@@ -46,19 +46,19 @@ perform file key = next $ cleanup file key
 
 cleanup :: FilePath -> Key -> CommandCleanup
 cleanup file key = do
-	g <- gitRepo
-
 	liftIO $ removeFile file
-	liftIO $ Git.run g "rm" [Params "--quiet --", File file]
+	inRepo $ Git.run "rm" [Params "--quiet --", File file]
 	-- git rm deletes empty directories; put them back
 	liftIO $ createDirectoryIfMissing True (parentDir file)
 
 	fast <- Annex.getState Annex.fast
 	if fast
-		then liftIO $ do
+		then do
 			-- fast mode: hard link to content in annex
-			createLink (gitAnnexLocation g key) file
-			allowWrite file
+			src <- fromRepo $ gitAnnexLocation key
+			liftIO $ do
+				createLink src file
+				allowWrite file
 		else do
 			fromAnnex key file
 			logStatus key InfoMissing

Command/Uninit.hs

@@ -28,11 +28,9 @@ check = do
 	when (b == Annex.Branch.name) $ error $
 		"cannot uninit when the " ++ b ++ " branch is checked out"
 	where
-		current_branch = do
-			g <- gitRepo
-			b <- liftIO $
-				Git.pipeRead g [Params "rev-parse --abbrev-ref HEAD"]
-			return $ head $ lines $ B.unpack b
+		current_branch = head . lines . B.unpack <$> revhead
+		revhead = inRepo $ Git.pipeRead 
+			[Params "rev-parse --abbrev-ref HEAD"]
 
 seek :: [CommandSeek]
 seek = [withFilesInGit startUnannex, withNothing start]
@@ -53,12 +51,11 @@ perform = next cleanup
 
 cleanup :: CommandCleanup
 cleanup = do
-	g <- gitRepo
+	annexdir <- fromRepo $ gitAnnexDir
 	uninitialize
 	mapM_ removeAnnex =<< getKeysPresent
-	liftIO $ removeDirectoryRecursive (gitAnnexDir g)
+	liftIO $ removeDirectoryRecursive annexdir
 	-- avoid normal shutdown
 	saveState
-	liftIO $ do
-		Git.run g "branch" [Param "-D", Param Annex.Branch.name]
-		exitSuccess
+	inRepo $ Git.run "branch" [Param "-D", Param Annex.Branch.name]
+	liftIO $ exitSuccess

Command/Unlock.hs

@@ -37,9 +37,8 @@ perform dest key = do
 	
 	checkDiskSpace key
 
-	g <- gitRepo
-	let src = gitAnnexLocation g key
-	let tmpdest = gitAnnexTmpLocation g key
+	src <- fromRepo $ gitAnnexLocation key
+	tmpdest <- fromRepo $ gitAnnexTmpLocation key
 	liftIO $ createDirectoryIfMissing True (parentDir tmpdest)
 	showAction "copying"
 	ok <- liftIO $ copyFileExternal src tmpdest

Command/Unused.hs

@@ -75,8 +75,8 @@ checkRemoteUnused' r = do
 
 writeUnusedFile :: FilePath -> [(Int, Key)] -> Annex ()
 writeUnusedFile prefix l = do
-	g <- gitRepo
-	liftIO $ viaTmp writeFile (gitAnnexUnusedLog prefix g) $
+	logfile <- fromRepo $ gitAnnexUnusedLog prefix
+	liftIO $ viaTmp writeFile logfile $
 		unlines $ map (\(n, k) -> show n ++ " " ++ show k) l
 
 table :: [(Int, Key)] -> [String]
@@ -147,8 +147,7 @@ unusedKeys = do
 excludeReferenced :: [Key] -> Annex [Key]
 excludeReferenced [] = return [] -- optimisation
 excludeReferenced l = do
-	g <- gitRepo
-	c <- liftIO $ Git.pipeRead g [Param "show-ref"]
+	c <- inRepo $ Git.pipeRead [Param "show-ref"]
 	removewith (getKeysReferenced : map getKeysReferencedInGit (refs c))
 		(S.fromList l)
 	where
@@ -183,8 +182,8 @@ exclude smaller larger = S.toList $ remove larger $ S.fromList smaller
 {- List of keys referenced by symlinks in the git repo. -}
 getKeysReferenced :: Annex [Key]
 getKeysReferenced = do
-	g <- gitRepo
-	files <- liftIO $ LsFiles.inRepo g [Git.workTree g]
+	top <- fromRepo Git.workTree
+	files <- inRepo $ LsFiles.inRepo [top]
 	keypairs <- mapM Backend.lookupFile files
 	return $ map fst $ catMaybes keypairs
 
@@ -192,8 +191,7 @@ getKeysReferenced = do
 getKeysReferencedInGit :: String -> Annex [Key]
 getKeysReferencedInGit ref = do
 	showAction $ "checking " ++ Git.refDescribe ref
-	g <- gitRepo
-	findkeys [] =<< liftIO (LsTree.lsTree g ref)
+	findkeys [] =<< inRepo (LsTree.lsTree ref)
 	where
 		findkeys c [] = return c
 		findkeys c (l:ls)
@@ -217,16 +215,14 @@ staleKeysPrune dirspec present = do
 	let stale = contents `exclude` present
 	let dups = contents `exclude` stale
 
-	g <- gitRepo
-	let dir = dirspec g
+	dir <- fromRepo dirspec
 	liftIO $ forM_ dups $ \t -> removeFile $ dir </> keyFile t
 
 	return stale
 
 staleKeys :: (Git.Repo -> FilePath) -> Annex [Key]
 staleKeys dirspec = do
-	g <- gitRepo
-	let dir = dirspec g
+	dir <- fromRepo dirspec
 	exists <- liftIO $ doesDirectoryExist dir
 	if not exists
 		then return []