From 43305f5a0e2a87c68405989600b33e33c1ab70df Mon Sep 17 00:00:00 2001
From: tv <tv@krebsco.de>
Date: Fri, 6 Nov 2026 07:04:33 +0100
Subject: partition registrations tested

---
 src/simtest/remakes.rs | 64 ++++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 64 insertions(+)

diff --git a/src/simtest/remakes.rs b/src/simtest/remakes.rs
index 4a193aa..ec83c40 100644
--- a/src/simtest/remakes.rs
+++ b/src/simtest/remakes.rs
@@ -479,6 +479,70 @@ async fn both_sides_of_an_old_partition_commit_and_converge() {
     assert_eq!(read(&e, "data").await, Some(json!(1)));
 }
 
+/// Electorates widened on one side: with three members and c cut off, d and e join
+/// through c and register there, so c's side counts 5 members (3 of them on its side)
+/// and a's side 3 (2 on its side). Each side's remake gets a majority of the electorate
+/// it sees, and both commit (`remakes.md`, Limits). Once the partition heals, the swarm
+/// ends on one epoch: the one more nodes are on.
+#[tokio::test(flavor = "multi_thread", worker_threads = 4)]
+async fn members_registered_during_a_partition_commit_on_their_side_and_converge() {
+    use crate::remake::Host;
+
+    let sim = Sim::new(40);
+    let (a, b, c) = three(&sim).await;
+    write(&a, "data", json!(1)).await;
+    sim.wait_converged(&[&a, &b, &c], SOON).await;
+
+    let cut = LinkParams {
+        loss: 1.0,
+        ..LinkParams::default()
+    };
+    let link = |params: &LinkParams| {
+        for one in ["a", "b"] {
+            for other in ["c", "d", "e"] {
+                sim.net.set_link(one, other, params.clone());
+                sim.net.set_link(other, one, params.clone());
+            }
+        }
+    };
+    link(&cut);
+    let [d, e] = ["d", "e"].map(|id| sim.start(id, &["c"], Start::Join));
+    sim.wait_ready(&[&d, &e], SOON).await;
+    let (a_ref, c_ref) = (&a, &c);
+    sim.wait_until("c's electorate is all five", SOON, move || async move {
+        let doc = c_ref.doc.read().await;
+        c_ref.electorate(&doc.doc, c_ref.now_millis()).len() == 5
+    })
+    .await;
+    {
+        let doc = a_ref.doc.read().await;
+        assert_eq!(a_ref.electorate(&doc.doc, a_ref.now_millis()).len(), 3);
+    }
+
+    propose(&a, json!({ "kind": "compact" })).await;
+    propose(&c, json!({ "kind": "compact" })).await;
+    on_generation(&sim, &[&a, &b], 1).await;
+    on_generation(&sim, &[&c, &d, &e], 1).await;
+    let larger = same_epoch(&[&c, &d, &e]);
+    assert_ne!(same_epoch(&[&a, &b]), larger, "two epochs of generation 1");
+
+    link(&LinkParams::default());
+    let all = [&a, &b, &c, &d, &e];
+    let all_ref = &all;
+    sim.wait_until("every node is on c's epoch", REMAKE, move || async move {
+        for node in all_ref {
+            if node.local_epoch() != larger || !node.is_ready().await {
+                return false;
+            }
+        }
+        true
+    })
+    .await;
+    for node in all {
+        assert_eq!(read(node, "data").await, Some(json!(1)));
+    }
+}
+
 /// A node whose clock is ahead sees a remake expire early: aborting it from there is
 /// refused while the node knows its clock is off (`?force=clock` overrides), as its
 /// coordinator, alive, may still commit it.
-- 
cgit v1.3.1