diff --git a/contrib/mock b/contrib/mock
index 933d5316..f7fc7bc3 100644
--- a/contrib/mock
+++ b/contrib/mock
@@ -32,8 +32,9 @@ _mock()
 			return 0
 			;;
 		-r|--root)
-			COMPREPLY=( $( command ls $cfgdir | \
-				sed -ne 's/^\('$cur'.*\)\.cfg$/\1/p') )
+			COMPREPLY=( $( compgen -W "$( command ls $cfgdir )" \
+				-- $cur ) )
+			COMPREPLY=( ${COMPREPLY[@]/%.cfg/} )
 			return 0
 			;;
 		--@(config|result)dir)