remove empty directories when removing from export

The subtle part of this is what happens when the remote fails to remove
an empty directory. The removal from the export needs to fail in that
case, so the removal will be tried again later. However, removeExportLocation
has already been run and changed the export db, so if the next run
checks getExportLocation, it might decide nothing remains to be done,
leaving the empty directory.

Dealt with that by making removeEmptyDirectories, handle a failure
by calling addExportLocation, reverting the database changes so the next
run will be guaranteed to try deleting the empty directory again.

This commit was sponsored by Thomas Hochstein on Patreon.

1 files changed, 11 insertions, 11 deletions

diff --git a/Command/Export.hs b/Command/Export.hs
index 2c75d0164..56676809f 100644
--- a/Command/Export.hs
+++ b/Command/Export.hs
@@ -25,6 +25,7 @@ import Annex.CatFile
 import Logs.Location
 import Logs.Export
 import Database.Export
+import Remote.Helper.Export
 import Messages.Progress
 import Utility.Tmp
 
@@ -252,24 +253,24 @@ startUnexport' r ea db f ek = do
 performUnexport :: Remote -> ExportActions Annex -> ExportHandle -> [ExportKey] -> ExportLocation -> CommandPerform
 performUnexport r ea db eks loc = do
 	ifM (allM (\ek -> removeExport ea (asKey ek) loc) eks)
-		( next $ cleanupUnexport r db eks loc
+		( next $ cleanupUnexport r ea db eks loc
 		, stop
 		)
 
-cleanupUnexport :: Remote -> ExportHandle -> [ExportKey] -> ExportLocation -> CommandCleanup
-cleanupUnexport r db eks loc = do
+cleanupUnexport :: Remote -> ExportActions Annex -> ExportHandle -> [ExportKey] -> ExportLocation -> CommandCleanup
+cleanupUnexport r ea db eks loc = do
 	liftIO $ do
 		forM_ eks $ \ek ->
 			removeExportLocation db (asKey ek) loc
-		-- Flush so that getExportLocation sees this and any
-		-- other removals of the key.
 		flushDbQueue db
+
 	remaininglocs <- liftIO $ 
 		concat <$> forM eks (\ek -> getExportLocation db (asKey ek))
 	when (null remaininglocs) $
 		forM_ eks $ \ek ->
 			logChange (asKey ek) (uuid r) InfoMissing
-	return True
+	
+	removeEmptyDirectories ea db loc (map asKey eks)
 
 startRecoverIncomplete :: Remote -> ExportActions Annex -> ExportHandle -> Git.Sha -> TopFilePath -> CommandStart
 startRecoverIncomplete r ea db sha oldf
@@ -306,7 +307,7 @@ startMoveFromTempName r ea db ek f = do
 performRename :: Remote -> ExportActions Annex -> ExportHandle -> ExportKey -> ExportLocation -> ExportLocation -> CommandPerform
 performRename r ea db ek src dest = do
 	ifM (renameExport ea (asKey ek) src dest)
-		( next $ cleanupRename db ek src dest
+		( next $ cleanupRename ea db ek src dest
 		-- In case the special remote does not support renaming,
 		-- unexport the src instead.
 		, do
@@ -314,11 +315,10 @@ performRename r ea db ek src dest = do
 			performUnexport r ea db [ek] src
 		)
 
-cleanupRename :: ExportHandle -> ExportKey -> ExportLocation -> ExportLocation -> CommandCleanup
-cleanupRename db ek src dest = do
+cleanupRename :: ExportActions Annex -> ExportHandle -> ExportKey -> ExportLocation -> ExportLocation -> CommandCleanup
+cleanupRename ea db ek src dest = do
 	liftIO $ do
 		removeExportLocation db (asKey ek) src
 		addExportLocation db (asKey ek) dest
-		-- Flush so that getExportLocation sees this.
 		flushDbQueue db
-	return True
+	removeEmptyDirectories ea db src [asKey ek]