git-annex/Git/DiffTree.hs
Joey Hess 6db4aee7df
use --no-abbrev instead of --abbrev=40
This avoids hardcoding the sha size, so when git uses sha256, it will
output the full sha256 and not a truncation to 40 characters.

I reviewed git's history, and while there have been some
bugs with commands not supporting --no-abbrev (eg git diff --no-index
--no-abbrev was broken in git 2.1), none of the commands git-annex
uses will be impacted by those old bugs.
2020-01-07 12:29:37 -04:00

125 lines
3.9 KiB
Haskell

{- git diff-tree interface
-
- Copyright 2012 Joey Hess <id@joeyh.name>
-
- Licensed under the GNU AGPL version 3 or higher.
-}
module Git.DiffTree (
DiffTreeItem(..),
isDiffOf,
diffTree,
diffTreeRecursive,
diffIndex,
diffWorkTree,
diffFiles,
diffLog,
commitDiff,
) where
import Numeric
import Common
import Git
import Git.Sha
import Git.Command
import Git.FilePath
import Git.DiffTreeItem
import qualified Git.Filename
import qualified Git.Ref
{- Checks if the DiffTreeItem modifies a file with a given name
- or under a directory by that name. -}
isDiffOf :: DiffTreeItem -> TopFilePath -> Bool
isDiffOf diff f = case fromRawFilePath (getTopFilePath f) of
"" -> True -- top of repo contains all
d -> d `dirContains` fromRawFilePath (getTopFilePath (file diff))
{- 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), Param "--"]
{- 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), Param "--"]
{- 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, or 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] ++ [Param "--"] )
repo
, return ([], return True)
)
{- Diff between the index and work tree. -}
diffFiles :: [CommandParam] -> Repo -> IO ([DiffTreeItem], IO Bool)
diffFiles = getdiff (Param "diff-files")
{- Runs git log in --raw mode to get the changes that were made in
- a particular commit to particular files. The output format
- is adjusted to be the same as diff-tree --raw._-}
diffLog :: [CommandParam] -> Repo -> IO ([DiffTreeItem], IO Bool)
diffLog params = getdiff (Param "log")
(Param "-n1" : Param "--no-abbrev" : Param "--pretty=format:" : params)
{- Uses git show to get the changes made by a commit.
-
- Does not support merge commits, and will fail on them. -}
commitDiff :: Sha -> Repo -> IO ([DiffTreeItem], IO Bool)
commitDiff ref = getdiff (Param "show")
[ Param "--no-abbrev", Param "--pretty=", Param "--raw", Param (fromRef ref) ]
getdiff :: CommandParam -> [CommandParam] -> Repo -> IO ([DiffTreeItem], IO Bool)
getdiff command params repo = do
(diff, cleanup) <- pipeNullSplit ps repo
return (parseDiffRaw (map decodeBL diff), cleanup)
where
ps =
command :
Param "-z" :
Param "--raw" :
Param "--no-renames" :
Param "-l0" :
params
{- Parses --raw output used by diff-tree and git-log. -}
parseDiffRaw :: [String] -> [DiffTreeItem]
parseDiffRaw l = go l
where
go [] = []
go (info:f:rest) = mk info f : go rest
go (s:[]) = error $ "diff-tree parse error near \"" ++ 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 $ toRawFilePath f
}
where
readmode = fst . Prelude.head . readOct
-- info = :<srcmode> SP <dstmode> SP <srcsha> SP <dstsha> SP <status>
(srcm, past_srcm) = splitAt 7 $ drop 1 info
(dstm, past_dstm) = splitAt 7 past_srcm
(ssha, past_ssha) = separate (== ' ') past_dstm
(dsha, s) = separate (== ' ') past_ssha