json object for FileNotFound

When a nonexistant file is passed to a command and  --json-error-messages
is enabled, output a JSON object indicating the problem.

(But git ls-files --error-unmatch still displays errors about such files in
some situations.)

I don't like the duplication of the name of the command introduced by this,
but I can't see a great way around it. One way would be to pass the Command
instead.

When json is not enabled, the stderr is unchanged. This is necessary
because some commands like find have custom output. So dislaying
"find foo not found" would be wrong. So had to complicate things with
toplevelFileProblem having different output with and without json.

When not using --json-error-messages but still using --json, it displays
the error to stderr, but does display a json object without the error. It
does have an errorid though. Unsure how useful that behavior is.

Sponsored-by: Dartmouth College's Datalad project

Command/Add.hs

@@ -119,7 +119,7 @@ seek o = startConcurrency commandStages $ do
 			-- are not known to git yet, since this will add
 			-- them. Instead, have workTreeItems warn about other
 			-- problems, like files that don't exist.
-			let ww = WarnUnmatchWorkTreeItems
+			let ww = WarnUnmatchWorkTreeItems "add"
 			l <- workTreeItems ww (addThese o)
 			let go b a = a ww (commandAction . gofile b) l
 			unless (updateOnly o) $

Command/Copy.hs

@@ -60,7 +60,7 @@ seek' o fto = startConcurrency (Command.Move.stages fto) $ do
 		Batch fmt -> batchOnly (keyOptions o) (copyFiles o) $
 			batchAnnexed fmt seeker keyaction
   where
-	ww = WarnUnmatchLsFiles
+	ww = WarnUnmatchLsFiles "copy"
 	
 	seeker = AnnexedFileSeeker
 		{ startAction = start o fto

Command/Drop.hs

@@ -74,7 +74,7 @@ seek o = startConcurrency commandStages $ do
 		Batch fmt -> batchOnly (keyOptions o) (dropFiles o) $
 			batchAnnexed fmt seeker (startKeys o from)
   where
-	ww = WarnUnmatchLsFiles
+	ww = WarnUnmatchLsFiles "drop"
 
 start :: DropOptions -> Maybe Remote -> SeekInput -> RawFilePath -> Key -> CommandStart
 start o from si file key = start' o from key afile ai si

Command/FilterBranch.hs

@@ -192,4 +192,4 @@ seek o = withOtherTmp $ \tmpdir -> do
 	c <- inRepo $ Git.commitTree cmode cmessage [] t
 	liftIO $ putStrLn (fromRef c)
   where
-	ww = WarnUnmatchLsFiles
+	ww = WarnUnmatchLsFiles "filter-branch"

Command/Find.hs

@@ -75,7 +75,7 @@ seek o = do
 		Batch fmt -> batchOnly (keyOptions o) (findThese o) $
 			batchAnnexedFiles fmt seeker
   where
-	ww = WarnUnmatchLsFiles
+	ww = WarnUnmatchLsFiles "find"
 
 -- Default to needing content to be present, but if the user specified a
 -- limit, content does not need to be present.

Command/Fix.hs

@@ -35,7 +35,7 @@ seek :: CmdParams -> CommandSeek
 seek ps = unlessM crippledFileSystem $
 	withFilesInGitAnnex ww seeker =<< workTreeItems ww ps
   where
-	ww = WarnUnmatchLsFiles
+	ww = WarnUnmatchLsFiles "fix"
 	seeker = AnnexedFileSeeker
 		{ startAction = start FixAll
 		, checkContentPresent = Nothing

Command/Fsck.hs

@@ -113,7 +113,7 @@ seek o = startConcurrency commandStages $ do
 	cleanupIncremental i
 	void $ tryIO $ recordActivity Fsck u
   where
-	ww = WarnUnmatchLsFiles
+	ww = WarnUnmatchLsFiles "fsck"
 
 checkDeadRepo :: UUID -> Annex ()
 checkDeadRepo u =

Command/Get.hs

@@ -53,7 +53,7 @@ seek o = startConcurrency transferStages $ do
 		Batch fmt -> batchOnly (keyOptions o) (getFiles o) $
 			batchAnnexed fmt seeker (startKeys from)
   where
-	ww = WarnUnmatchLsFiles
+	ww = WarnUnmatchLsFiles "get"
 
 start :: GetOptions -> Maybe Remote -> SeekInput -> RawFilePath -> Key -> CommandStart
 start o from si file key = start' expensivecheck from key afile ai si

Command/Inprogress.hs

@@ -49,7 +49,7 @@ seek o = do
 			withFilesInGitAnnex ww seeker
 				=<< workTreeItems ww (inprogressFiles o)
   where
-	ww = WarnUnmatchLsFiles
+	ww = WarnUnmatchLsFiles "inprogress"
 
 start :: IsTerminal -> S.Set Key -> SeekInput -> RawFilePath -> Key -> CommandStart
 start isterminal s _si _file k

Command/List.hs

@@ -56,7 +56,7 @@ seek o = do
 		}
 	withFilesInGitAnnex ww seeker =<< workTreeItems ww (listThese o)
   where
-	ww = WarnUnmatchLsFiles
+	ww = WarnUnmatchLsFiles "list"
 
 getList :: ListOptions -> Annex [(UUID, RemoteName, TrustLevel)]
 getList o

Command/Lock.hs

@@ -32,7 +32,7 @@ cmd = withAnnexOptions [jsonOptions, annexedMatchingOptions] $
 seek :: CmdParams -> CommandSeek
 seek ps = withFilesInGitAnnex ww seeker =<< workTreeItems ww ps
   where
-	ww = WarnUnmatchLsFiles
+	ww = WarnUnmatchLsFiles "lock"
 	seeker = AnnexedFileSeeker
 		{ startAction = start
 		, checkContentPresent = Nothing

Command/Log.hs

@@ -105,7 +105,7 @@ seek o = ifM (null <$> Annex.Branch.getUnmergedRefs)
 	, giveup "This repository is read-only, and there are unmerged git-annex branches, which prevents displaying location log changes. (Set annex.merge-annex-branches to false to ignore the unmerged git-annex branches.)"
 	)
   where
-	ww = WarnUnmatchLsFiles
+	ww = WarnUnmatchLsFiles "log"
 
 start :: LogOptions -> (FilePath -> Outputter) -> SeekInput -> RawFilePath -> Key -> CommandStart
 start o outputter _ file key = do

Command/MetaData.hs

@@ -76,7 +76,7 @@ seek :: MetaDataOptions -> CommandSeek
 seek o = case batchOption o of
 	NoBatch -> do
 		c <- currentVectorClock
-		let ww = WarnUnmatchLsFiles
+		let ww = WarnUnmatchLsFiles "metadata"
 		let seeker = AnnexedFileSeeker
 			{ startAction = start c o
 			, checkContentPresent = Nothing

Command/Migrate.hs

@@ -41,7 +41,7 @@ optParser desc = MigrateOptions
 seek :: MigrateOptions -> CommandSeek
 seek o = withFilesInGitAnnex ww seeker =<< workTreeItems ww (migrateThese o)
   where
-	ww = WarnUnmatchLsFiles
+	ww = WarnUnmatchLsFiles "migrate"
 	seeker = AnnexedFileSeeker
 		{ startAction = start o
 		, checkContentPresent = Nothing

Command/Mirror.hs

@@ -50,7 +50,7 @@ seek o = startConcurrency stages $
 	stages = case fromToOptions o of
 		FromRemote _ -> transferStages
 		ToRemote _ -> commandStages
-	ww = WarnUnmatchLsFiles
+	ww = WarnUnmatchLsFiles "mirror"
 	seeker = AnnexedFileSeeker
 		{ startAction = start o
 		, checkContentPresent = Nothing

Command/Move.hs

@@ -84,7 +84,7 @@ seek' o fto = startConcurrency (stages fto) $ do
 		, usesLocationLog = True
 		}
 	keyaction = startKey fto (removeWhen o)
-	ww = WarnUnmatchLsFiles
+	ww = WarnUnmatchLsFiles "move"
 
 stages :: FromToHereOptions -> UsedStages
 stages (FromOrToRemote (FromRemote _)) = transferStages

Command/Multicast.hs

@@ -131,7 +131,7 @@ send ups fs = do
 	-- expensive.
 	starting "sending files" (ActionItemOther Nothing) (SeekInput []) $
 		withTmpFile "send" $ \t h -> do
-			let ww = WarnUnmatchLsFiles
+			let ww = WarnUnmatchLsFiles "multicast"
 			(fs', cleanup) <- seekHelper id ww LsFiles.inRepo
 				=<< workTreeItems ww fs
 			matcher <- Limit.getMatcher

Command/PreCommit.hs

@@ -32,10 +32,10 @@ cmd = command "pre-commit" SectionPlumbing
 
 seek :: CmdParams -> CommandSeek
 seek ps = do
-	let ww = WarnUnmatchWorkTreeItems
+	let ww = WarnUnmatchWorkTreeItems "pre-commit"
 	l <- workTreeItems ww ps
 	-- fix symlinks to files being committed
-	flip withFilesToBeCommitted l $ \(si, f) -> commandAction $
+	flip (withFilesToBeCommitted ww) l $ \(si, f) -> commandAction $
 		maybe stop (Command.Fix.start Command.Fix.FixSymlinks si f)
 			=<< isAnnexLink f
 	-- after a merge conflict or git cherry-pick or stash, pointer

Command/Sync.hs

@@ -794,7 +794,7 @@ seekSyncContent o rs currbranch = do
 		in seekFiltered (const (pure True)) filterer $
 			seekHelper id ww (LsFiles.inRepoOrBranch origbranch) l 
 
-	ww = WarnUnmatchLsFiles
+	ww = WarnUnmatchLsFiles "sync"
 
 	gofile bloom mvar _ f k = 
 		go (Right bloom) mvar (AssociatedFile (Just f)) k

Command/Unannex.hs

@@ -30,7 +30,7 @@ cmd = withAnnexOptions [annexedMatchingOptions] $
 seek :: CmdParams -> CommandSeek
 seek ps = withFilesInGitAnnex ww (seeker False) =<< workTreeItems ww ps
   where
-	ww = WarnUnmatchLsFiles
+	ww = WarnUnmatchLsFiles "unannex"
 
 seeker :: Bool -> AnnexedFileSeeker
 seeker fast = AnnexedFileSeeker

Command/Uninit.hs

@@ -53,13 +53,13 @@ seek ps = do
 	l <- workTreeItems ww ps
 	withFilesNotInGit
 		(CheckGitIgnore False)
-		WarnUnmatchWorkTreeItems
+		(WarnUnmatchWorkTreeItems "uninit")
 		checksymlinks
 		l
 	withFilesInGitAnnex ww (Command.Unannex.seeker True) l
 	finish
   where
-	ww = WarnUnmatchLsFiles
+	ww = WarnUnmatchLsFiles "uninit"
 	checksymlinks (_, f) = 
 		commandAction $ lookupKey f >>= \case
 			Nothing -> stop

Command/Unlock.hs

@@ -33,7 +33,7 @@ mkcmd n d = withAnnexOptions [jsonOptions, annexedMatchingOptions] $
 seek :: CmdParams -> CommandSeek
 seek ps = withFilesInGitAnnex ww seeker =<< workTreeItems ww ps
   where
-	ww = WarnUnmatchLsFiles
+	ww = WarnUnmatchLsFiles "unlock"
 	seeker = AnnexedFileSeeker
 		{ startAction = start
 		, checkContentPresent = Nothing

Command/Whereis.hs

@@ -64,7 +64,7 @@ seek o = do
 		Batch fmt -> batchOnly (keyOptions o) (whereisFiles o) $
 			batchAnnexed fmt seeker (startKeys o m)
   where
-	ww = WarnUnmatchLsFiles
+	ww = WarnUnmatchLsFiles "whereis"
 
 start :: WhereisOptions -> M.Map UUID Remote -> SeekInput -> RawFilePath -> Key -> CommandStart
 start o remotemap si file key =