Fix Message ednsflags propery setter.

Setting ednsflags to 0 shouldn't unconditionally enable EDNS.

diff --git a/dns/message.py b/dns/message.py
index 1bb02ae23a2e8029e0741bfd0f0d66840dd8839b..60b74c19ec9053f5c78eb41f8a13e49d6b284aab 100644 (file)
--- a/dns/message.py
+++ b/dns/message.py
@@ -614,7 +614,7 @@ class Message:
     def ednsflags(self, v):
         if self.opt:
             self.opt.ttl = v
-        else:
+        elif v:
             self.opt = self._make_opt(v)
 
     @property