sync: a member refused as a whole, synced with again once it changed document

A node refusing a member as a whole sent it nothing, and lifted that
only when a change of the member's was taken again. But a member that
dropped what was refused (REFUSALS) starts its sync sessions over, and
a fresh session sends no changes until the other side answers: the two
waited for each other, and the member stayed refused.

The refusal now notes the member's run and epoch_seq when it began; a
member with another document since (it dropped what was refused, or
rejoined) is synced with again.

1 files changed, 5 insertions, 0 deletions

diff --git a/src/state/peer.rs b/src/state/peer.rs
index e0b161d..f6e4a62 100644
--- a/src/state/peer.rs
+++ b/src/state/peer.rs
@@ -141,6 +141,10 @@ pub(crate) struct PeerState {
     pub(crate) epoch_seq: Option<u32>,
     /// The peer's run, from its HELLO or HELLO_REPLY: a new one starts `epoch_seq` over.
     pub(crate) run_id: Option<crate::transport::RunId>,
+    /// While we refuse the peer as a whole (`access::screen`): its run and `epoch_seq`
+    /// when we began to. Another means it has another document since (it dropped what
+    /// we refused, `swarm::refusals`, or rejoined): we sync with it again.
+    pub(crate) refused_with: Option<(Option<crate::transport::RunId>, Option<u32>)>,
     /// The newest handshake the peer started with us: its run and number
     /// (`HelloRequest::handshake`). A HELLO repeating it is a retry or a late copy.
     pub(crate) last_hello: Option<(crate::transport::RunId, u32)>,
@@ -319,6 +323,7 @@ impl PeerState {
             epoch: None,
             epoch_seq: None,
             run_id: None,
+            refused_with: None,
             last_hello: None,
             handshake: 0,
             reports_ready: None,