git-annex merge branch

* merge: When run with a branch parameter, merges from that branch.
  This is especially useful when using an adjusted branch, because
  it applies the same adjustment to the branch before merging it.

Command/Merge.hs

@@ -1,6 +1,6 @@
 {- git-annex command
  -
- - Copyright 2011, 2013 Joey Hess <id@joeyh.name>
+ - Copyright 2011-2019 Joey Hess <id@joeyh.name>
  -
  - Licensed under the GNU AGPL version 3 or higher.
  -}
@@ -9,27 +9,38 @@ module Command.Merge where
 
 import Command
 import qualified Annex.Branch
+import qualified Git
+import qualified Git.Branch
 import Annex.CurrentBranch
-import Command.Sync (prepMerge, mergeLocal, mergeConfig)
+import Command.Sync (prepMerge, mergeLocal, mergeConfig, merge)
 
 cmd :: Command
 cmd = command "merge" SectionMaintenance
-	"automatically merge changes from remotes"
-	paramNothing (withParams seek)
+	"merge changes from remotes"
+	(paramOptional paramRef) (withParams seek)
 
 seek :: CmdParams -> CommandSeek
-seek _ = do
-	commandAction mergeBranch
-	commandAction mergeSynced
+seek [] = do
+	prepMerge
+	commandAction mergeAnnexBranch
+	commandAction mergeSyncedBranch
+seek bs = do
+	prepMerge
+	forM_ bs (commandAction . mergeBranch . Git.Ref)
+seek _ = giveup ""
 
-mergeBranch :: CommandStart
-mergeBranch = starting "merge" (ActionItemOther (Just "git-annex")) $ do
+mergeAnnexBranch :: CommandStart
+mergeAnnexBranch = starting "merge" (ActionItemOther (Just "git-annex")) $ do
 	Annex.Branch.update
 	-- commit explicitly, in case no remote branches were merged
 	Annex.Branch.commit =<< Annex.Branch.commitMessage
 	next $ return True
 
-mergeSynced :: CommandStart
-mergeSynced = do
-	prepMerge
-	mergeLocal mergeConfig def =<< getCurrentBranch
+mergeSyncedBranch :: CommandStart
+mergeSyncedBranch = mergeLocal mergeConfig def =<< getCurrentBranch
+
+mergeBranch :: Git.Ref -> CommandStart
+mergeBranch r = starting "merge" (ActionItemOther (Just (Git.fromRef r))) $ do
+	currbranch <- getCurrentBranch
+	merge currbranch mergeConfig def Git.Branch.ManualCommit r
+	next $ return True