vyos.configdict: T4263: leaf_node_changed() must also honor valueLess CLI nodes

If a valueLess node is added or removed from the CLI, a call to
leaf_node_changed() will not detect it.

If node is valueLess, on change old or new (depending on addition or deletion)
will be {} and is treated as None.

Add handler for this special case where old or new is an instance of a
dictionary but empty.

1 files changed, 6 insertions, 0 deletions

diff --git a/python/vyos/configdict.py b/python/vyos/configdict.py
index f2ec93520..aea22c0c9 100644
--- a/python/vyos/configdict.py
+++ b/python/vyos/configdict.py
@@ -117,6 +117,12 @@ def leaf_node_changed(conf, path):
     D.set_level(conf.get_level())
     (new, old) = D.get_value_diff(path)
     if new != old:
+        if isinstance(old, dict):
+            # valueLess nodes return {} if node is deleted
+            return True
+        if old is None and isinstance(new, dict):
+            # valueLess nodes return {} if node was added
+            return True
         if old is None:
             return []
         if isinstance(old, str):