add writer trees

2 files changed, 6 insertions, 1 deletions

diff --git a/src/transport/mod.rs b/src/transport/mod.rs
index 9ae8ff2..899f4b8 100644
--- a/src/transport/mod.rs
+++ b/src/transport/mod.rs
@@ -670,6 +670,10 @@ pub(crate) struct SyncEnvelope {
     /// not one it is still filling (joining, rejoining). Only such a peer can tell a
     /// catching-up node that it has everything; an empty document says nothing else.
     pub(crate) ready: bool,
+    /// Whose change it passes on along the writer's tree (`swarm::tree`), by pair key:
+    /// the writer's, on its own push and on every member's after; None otherwise
+    /// (answers, pulls).
+    pub(crate) writer: Option<u64>,
 }
 
 /// What a sync envelope carries.
diff --git a/src/transport/wire.rs b/src/transport/wire.rs
index a6ca286..8e3baa6 100644
--- a/src/transport/wire.rs
+++ b/src/transport/wire.rs
@@ -14,7 +14,7 @@ use super::{EncodedMessage, MessageKind, ParsedMessage};
 
 /// The wire format's version, the first byte of every payload. Bump it with every change
 /// to a message type or a codec (`golden_bytes` fails then).
-pub(crate) const VERSION: u8 = 21;
+pub(crate) const VERSION: u8 = 22;
 
 /// What the second byte of a payload says.
 fn tag(kind: MessageKind) -> u8 {
@@ -410,6 +410,7 @@ pub(crate) fn samples() -> Vec<ParsedMessage> {
                 to: vec![ChangeHash([2; 32])],
             }),
             ready: true,
+            writer: Some(7),
         }),
         ParsedMessage::Status(status.clone()),
         ParsedMessage::StatusReply(status),