--debug is passed along to git-annex-shell when git-annex is in debug mode.

Messages.hs

@@ -32,6 +32,7 @@ module Messages (
 	setupConsole,
 	enableDebugOutput,
 	disableDebugOutput,
+	debugEnabled,
 	commandProgressDisabled,
 ) where
 
@@ -191,6 +192,12 @@ enableDebugOutput = updateGlobalLogger rootLoggerName $ setLevel DEBUG
 disableDebugOutput :: IO ()
 disableDebugOutput = updateGlobalLogger rootLoggerName $ setLevel NOTICE
 
+{- Checks if debugging is enabled. -}
+debugEnabled :: IO Bool
+debugEnabled = do
+	l <- getRootLogger
+	return $ getLevel l <= Just DEBUG
+
 {- Should commands that normally output progress messages have that
  - output disabled? -}
 commandProgressDisabled :: Annex Bool