sync, assistant: When merge.directoryRenames is not set, default it it to "false"

Works better with automatic merge conflict resolution than git's ususual
default of "conflict".

This is not done when automatic merge conflict resolution is disabled.

This commit was sponsored by Mark Reidenbach on Patreon.

Annex/AdjustedBranch.hs

@@ -402,7 +402,7 @@ mergeToAdjustedBranch tomerge (origbranch, adj) mergeconfig canresolvemerge comm
 				-- http://thread.gmane.org/gmane.comp.version-control.git/297237
 				inRepo $ Git.Command.run [Param "reset", Param "HEAD", Param "--quiet"]
 				showAction $ "Merging into " ++ fromRef (Git.Ref.base origbranch)
-				merged <- autoMergeFrom' tomerge Nothing mergeconfig commitmode
+				merged <- autoMergeFrom' tomerge Nothing mergeconfig commitmode True
 					(const $ resolveMerge (Just updatedorig) tomerge True)
 				if merged
 					then do

Annex/AutoMerge.hs

@@ -15,6 +15,7 @@ module Annex.AutoMerge
 	) where
 
 import Annex.Common
+import qualified Annex
 import qualified Annex.Queue
 import Annex.CatFile
 import Annex.Link
@@ -46,22 +47,41 @@ import qualified Data.ByteString.Lazy as L
  -}
 autoMergeFrom :: Git.Ref -> Maybe Git.Ref -> [Git.Merge.MergeConfig] -> Git.Branch.CommitMode -> Bool -> Annex Bool
 autoMergeFrom branch currbranch mergeconfig commitmode canresolvemerge =
-	autoMergeFrom' branch currbranch mergeconfig commitmode resolvemerge
+	autoMergeFrom' branch currbranch mergeconfig commitmode canresolvemerge resolvemerge
   where
 	resolvemerge old
 		| canresolvemerge = resolveMerge old branch False
 		| otherwise = return False 
 
-autoMergeFrom' :: Git.Ref -> Maybe Git.Ref -> [Git.Merge.MergeConfig] -> Git.Branch.CommitMode -> (Maybe Git.Ref -> Annex Bool) -> Annex Bool
+autoMergeFrom' :: Git.Ref -> Maybe Git.Ref -> [Git.Merge.MergeConfig] -> Git.Branch.CommitMode -> Bool -> (Maybe Git.Ref -> Annex Bool) -> Annex Bool
-autoMergeFrom' branch currbranch mergeconfig commitmode resolvemerge = do
+autoMergeFrom' branch currbranch mergeconfig commitmode willresolvemerge toresolvemerge = do
 	showOutput
 	case currbranch of
 		Nothing -> go Nothing
 		Just b -> go =<< inRepo (Git.Ref.sha b)
   where
 	go old = do
-			r <- inRepo (Git.Merge.merge branch mergeconfig commitmode)
+			-- merge.directoryRenames=conflict plus automatic
-				<||> (resolvemerge old <&&> commitResolvedMerge commitmode)
+			-- merge conflict resolution results in files in a
+			-- "renamed" directory getting variant names,
+			-- so is not a great combination. If the user has
+			-- explicitly set it, use it, but otherwise when
+			-- merge conflicts will be resolved, override
+			-- to merge.directoryRenames=false.
+			overridedirectoryrenames <- if willresolvemerge
+				then isNothing . mergeDirectoryRenames
+					<$> Annex.getGitConfig
+				else pure False
+			let f r 
+				| overridedirectoryrenames = r
+					{ Git.gitGlobalOpts = 
+						Param "-c"
+						: Param "merge.directoryRenames=false" 
+						: Git.gitGlobalOpts r
+					}
+				| otherwise = r
+			r <- inRepo (Git.Merge.merge branch mergeconfig commitmode . f)
+				<||> (toresolvemerge old <&&> commitResolvedMerge commitmode)
 			-- Merging can cause new associated files to appear
 			-- and the smudge filter will add them to the database.
 			-- To ensure that this process sees those changes,

CHANGELOG

@@ -33,6 +33,10 @@ git-annex (8.20200815) UNRELEASED; urgency=medium
   * import: Retry downloads that fail, same as is done for downloads generally.
   * resolvemerge: Improve cleanup of files that were deleted by one side of
     a conflicted merge, and modified by the other side.
+  * sync, assistant, merge: When merge.directoryRenames is not set,
+    default it it to "false", which works better with automatic merge
+    conflict resolution than git's ususual default of "conflict".
+    (This is not done when automatic merge conflict resolution is disabled.)
 
  -- Joey Hess <id@joeyh.name>  Fri, 14 Aug 2020 14:57:45 -0400
 

Types/GitConfig.hs

@@ -130,6 +130,7 @@ data GitConfig = GitConfig
 	, receiveDenyCurrentBranch :: DenyCurrentBranch
 	, gcryptId :: Maybe String
 	, gpgCmd :: GpgCmd
+	, mergeDirectoryRenames :: Maybe String
 	}
 
 extractGitConfig :: ConfigSource -> Git.Repo -> GitConfig
@@ -223,6 +224,7 @@ extractGitConfig configsource r = GitConfig
 	, receiveDenyCurrentBranch = getDenyCurrentBranch r
 	, gcryptId = getmaybe "core.gcrypt-id"
 	, gpgCmd = mkGpgCmd (getmaybe "gpg.program")
+	, mergeDirectoryRenames = getmaybe "directoryrenames"
 	}
   where
 	getbool k d = fromMaybe d $ getmaybebool k

doc/bugs/new_merge.directoryRenames_behavior_breaks_sync_merge_conflict_resolution.mdwn

@@ -46,3 +46,5 @@ to detect it and handle it specially.
 > git-annex sync should set merge.directoryRenames=false when
 > merge.directoryRenames is not configured, unless automatic merge conflict
 > resolution is disabled. --[[Joey]]
+>
+> > [[done]] --[[Joey]]