git-annex/Command/DiffDriver.hs
2024-08-24 09:28:41 -04:00

149 lines
3.9 KiB
Haskell

{- git-annex command
-
- Copyright 2014-2023 Joey Hess <id@joeyh.name>
-
- Licensed under the GNU AGPL version 3 or higher.
-}
module Command.DiffDriver where
import Command
import Annex.Content
import Annex.Link
import Git.Types
import qualified Command.Get
cmd :: Command
cmd = command "diffdriver" SectionPlumbing
"git diff driver"
("-- cmd --") (seek <$$> optParser)
data Options = Options
{ textDiff :: Bool
, getOption :: Bool
, restOptions :: CmdParams
}
optParser :: CmdParamsDesc -> Parser Options
optParser desc = Options
<$> switch
( long "text"
<> help "diff text files with diff(1)"
)
<*> switch
( long "get"
<> help "get file contents from remotes"
)
<*> cmdParams desc
seek :: Options -> CommandSeek
seek opts = do
let (req, differ) = parseReq opts
void $ liftIO . exitBool =<< liftIO . differ =<< fixupReq req opts
data Req
= Req
{ rPath :: FilePath
, rOldFile :: FilePath
, rOldHex :: String
, rOldMode :: String
, rNewFile :: FilePath
, rNewHex :: String
, rNewMode ::String
}
| UnmergedReq
{ rPath :: FilePath
}
type Differ = Req -> IO Bool
serializeReq :: Req -> [CommandParam]
serializeReq req@(UnmergedReq {}) = [Param $ rPath req]
serializeReq req@(Req {}) = map Param
[ rPath req
, rOldFile req
, rOldHex req
, rOldMode req
, rNewFile req
, rNewHex req
, rNewMode req
]
parseReq :: Options -> (Req, Differ)
parseReq opts
| textDiff opts = case separate (== "--") (restOptions opts) of
(_,[]) -> (mk (restOptions opts), textDiffer [])
(ps,rest) -> (mk rest, textDiffer ps)
| otherwise = case separate (== "--") (restOptions opts) of
(c:ps, l) -> (mk l, externalDiffer c ps)
([],_) -> badopts
where
mk (path:old_file:old_hex:old_mode:new_file:new_hex:new_mode:[]) =
Req
{ rPath = path
, rOldFile = old_file
, rOldHex = old_hex
, rOldMode = old_mode
, rNewFile = new_file
, rNewHex = new_hex
, rNewMode = new_mode
}
mk (unmergedpath:[]) = UnmergedReq { rPath = unmergedpath }
mk _ = badopts
badopts = giveup $ "Unexpected input: " ++ unwords (restOptions opts)
{- Check if either file is a symlink to a git-annex object,
- which git-diff will leave as a normal file containing the link text.
-
- Also check if either file is a pointer file, as used for unlocked files.
-
- In either case, adjust the Req to instead point to the actual
- location of the annexed object (which may or may not be present).
-
- This also gets objects from remotes when the getOption is set.
-}
fixupReq :: Req -> Options -> Annex Req
fixupReq req@(UnmergedReq {}) _ = return req
fixupReq req@(Req {}) opts =
check rOldFile rOldMode setoldfile req
>>= check rNewFile rNewMode setnewfile
where
setoldfile r@(Req {}) f = r { rOldFile = f }
setoldfile r@(UnmergedReq {}) _ = r
setnewfile r@(Req {}) f = r { rNewFile = f }
setnewfile r@(UnmergedReq {}) _ = r
check getfile getmode setfile r = case readTreeItemType (encodeBS (getmode r)) of
Just TreeSymlink -> do
v <- getAnnexLinkTarget' f False
maybe (return r) go (parseLinkTargetOrPointer =<< v)
_ -> maybe (return r) go =<< liftIO (isPointerFile f)
where
f = toRawFilePath (getfile r)
go k = do
when (getOption opts) $
unlessM (inAnnex k) $
commandAction $
starting "get" ai si $
Command.Get.perform NoLiveUpdate k af
repoint k
where
ai = OnlyActionOn k (ActionItemKey k)
si = SeekInput []
af = AssociatedFile (Just f)
repoint k = withObjectLoc k $
pure . setfile r . fromRawFilePath
externalDiffer :: String -> [String] -> Differ
externalDiffer c ps = \req -> boolSystem c (map Param ps ++ serializeReq req )
textDiffer :: [String] -> Differ
textDiffer diffopts req = do
putStrLn ("diff a/" ++ rPath req ++ " b/" ++ rPath req)
-- diff exits nonzero on difference, so ignore exit status
void $ boolSystem "diff" $
[ Param "-u"
, Param (rOldFile req)
, Param (rNewFile req)
] ++ map Param diffopts
return True