fts: avoid a memory leak edge case

* lib/fts.c (fts_open): Set an appropriate fts_level
so that an immediate fts_close() will free the allocation.
* tests/test-fts.c (fts_dealloc): Add a test case which
will trigger under valgrind or address sanitizer.
Fixes https://bugs.gnu.org/31439

1 files changed, 1 insertions, 0 deletions

diff --git a/lib/fts.c b/lib/fts.c
index d543510595..1ccc78c116 100644
--- a/lib/fts.c
+++ b/lib/fts.c
@@ -546,6 +546,7 @@ fts_open (char * const *argv,
                 goto mem3;
         sp->fts_cur->fts_link = root;
         sp->fts_cur->fts_info = FTS_INIT;
+        sp->fts_cur->fts_level = 1;
         if (! setup_dir (sp))
                 goto mem3;