git-annex/Git/DiffTree.hs
Joey Hess 4e0be2792b remove Read instance for Ref
Removed instance, got it all to build using fromRef. (With a few things
that really need to show something using a ref for debugging stubbed out.)

Then added back Read instance, and made Logs.View use it for serialization.
This changes the view log format.
2014-02-19 01:19:57 -04:00

102 lines
3 KiB
Haskell

{- git diff-tree interface
-
- Copyright 2012 Joey Hess <joey@kitenet.net>
-
- Licensed under the GNU GPL version 3 or higher.
-}
module Git.DiffTree (
DiffTreeItem(..),
diffTree,
diffTreeRecursive,
diffIndex,
diffWorkTree,
) where
import Numeric
import System.Posix.Types
import Common
import Git
import Git.Sha
import Git.Command
import Git.FilePath
import qualified Git.Filename
import qualified Git.Ref
data DiffTreeItem = DiffTreeItem
{ srcmode :: FileMode
, dstmode :: FileMode
, srcsha :: Sha -- nullSha if file was added
, dstsha :: Sha -- nullSha if file was deleted
, status :: String
, file :: TopFilePath
} deriving Show
{- Diffs two tree Refs. -}
diffTree :: Ref -> Ref -> Repo -> IO ([DiffTreeItem], IO Bool)
diffTree src dst = getdiff (Param "diff-tree")
[Param (fromRef src), Param (fromRef dst)]
{- Diffs two tree Refs, recursing into sub-trees -}
diffTreeRecursive :: Ref -> Ref -> Repo -> IO ([DiffTreeItem], IO Bool)
diffTreeRecursive src dst = getdiff (Param "diff-tree")
[Param "-r", Param (fromRef src), Param (fromRef dst)]
{- Diffs between a tree and the index. Does nothing if there is not yet a
- commit in the repository. -}
diffIndex :: Ref -> Repo -> IO ([DiffTreeItem], IO Bool)
diffIndex ref = diffIndex' ref [Param "--cached"]
{- Diffs between a tree and the working tree. Does nothing if there is not
- yet a commit in the repository, of if the repository is bare. -}
diffWorkTree :: Ref -> Repo -> IO ([DiffTreeItem], IO Bool)
diffWorkTree ref repo =
ifM (Git.Ref.headExists repo)
( diffIndex' ref [] repo
, return ([], return True)
)
diffIndex' :: Ref -> [CommandParam] -> Repo -> IO ([DiffTreeItem], IO Bool)
diffIndex' ref params repo =
ifM (Git.Ref.headExists repo)
( getdiff (Param "diff-index")
( params ++ [Param $ fromRef ref] )
repo
, return ([], return True)
)
getdiff :: CommandParam -> [CommandParam] -> Repo -> IO ([DiffTreeItem], IO Bool)
getdiff command params repo = do
(diff, cleanup) <- pipeNullSplit ps repo
return (parseDiffTree diff, cleanup)
where
ps = command : Params "-z --raw --no-renames -l0" : params
{- Parses diff-tree output. -}
parseDiffTree :: [String] -> [DiffTreeItem]
parseDiffTree l = go l []
where
go [] c = c
go (info:f:rest) c = go rest (mk info f : c)
go (s:[]) _ = error $ "diff-tree parse error " ++ s
mk info f = DiffTreeItem
{ srcmode = readmode srcm
, dstmode = readmode dstm
, srcsha = fromMaybe (error "bad srcsha") $ extractSha ssha
, dstsha = fromMaybe (error "bad dstsha") $ extractSha dsha
, status = s
, file = asTopFilePath $ fromInternalGitPath $ Git.Filename.decode f
}
where
readmode = fst . Prelude.head . readOct
-- info = :<srcmode> SP <dstmode> SP <srcsha> SP <dstsha> SP <status>
-- All fields are fixed, so we can pull them out of
-- specific positions in the line.
(srcm, past_srcm) = splitAt 7 $ drop 1 info
(dstm, past_dstm) = splitAt 7 past_srcm
(ssha, past_ssha) = splitAt shaSize past_dstm
(dsha, past_dsha) = splitAt shaSize $ drop 1 past_ssha
s = drop 1 past_dsha