git-annex/Command/ResolveMerge.hs
Joey Hess 0a4479b8ec
Avoid backtraces on expected failures when built with ghc 8; only use backtraces for unexpected errors.
ghc 8 added backtraces on uncaught errors. This is great, but git-annex was
using error in many places for a error message targeted at the user, in
some known problem case. A backtrace only confuses such a message, so omit it.

Notably, commands like git annex drop that failed due to eg, numcopies,
used to use error, so had a backtrace.

This commit was sponsored by Ethan Aubin.
2016-11-15 21:29:54 -04:00

40 lines
1 KiB
Haskell

{- git-annex command
-
- Copyright 2014 Joey Hess <id@joeyh.name>
-
- Licensed under the GNU GPL version 3 or higher.
-}
module Command.ResolveMerge where
import Command
import qualified Git
import Git.Sha
import qualified Git.Branch
import Annex.AutoMerge
cmd :: Command
cmd = command "resolvemerge" SectionPlumbing
"resolve merge conflicts"
paramNothing (withParams seek)
seek :: CmdParams -> CommandSeek
seek = withNothing start
start :: CommandStart
start = do
showStart "resolvemerge" ""
us <- fromMaybe nobranch <$> inRepo Git.Branch.current
d <- fromRepo Git.localGitDir
let merge_head = d </> "MERGE_HEAD"
them <- fromMaybe (error nomergehead) . extractSha
<$> liftIO (readFile merge_head)
ifM (resolveMerge (Just us) them False)
( do
void $ commitResolvedMerge Git.Branch.ManualCommit
next $ next $ return True
, giveup "Merge conflict could not be automatically resolved."
)
where
nobranch = giveup "No branch is currently checked out."
nomergehead = giveup "No SHA found in .git/merge_head"