Keep confirmed Watch snapshots current

crates/storage/tests/mobile_watch.rs

@@ -261,6 +261,33 @@ fn duplicate_delivery_after_watch_restart_recovers_a_lost_acknowledgement() -> T
     Ok(())
 }
 
+#[test]
+fn confirmed_unchanged_snapshot_stays_current_when_republished() -> TestResult {
+    let directory = tempfile::tempdir()?;
+    let journal = directory.path().join("watch-snapshot.toml");
+    let entries = || vec![entry("otp/alice", "Acme", "alice", b"secret")];
+    let mut sender = WatchSnapshotSender::load(journal.clone());
+    let first = sender.prepare("paired-watch", entries())?;
+    let receipt = WatchRuntime::default()
+        .apply_snapshot(first.snapshot().expose().to_vec())?
+        .receipt()
+        .to_vec();
+    assert_eq!(
+        sender.acknowledge(&receipt)?.state(),
+        MobileWatchSnapshotState::Current
+    );
+
+    assert_eq!(sender.prepare("paired-watch", entries())?.revision(), 1);
+    assert_eq!(sender.status().state(), MobileWatchSnapshotState::Current);
+    let mut reloaded = WatchSnapshotSender::load(journal);
+    assert_eq!(reloaded.status().state(), MobileWatchSnapshotState::Current);
+    reloaded.prepare("paired-watch", entries())?;
+    assert_eq!(reloaded.status().state(), MobileWatchSnapshotState::Current);
+    assert_eq!(reloaded.prepare("paired-watch", Vec::new())?.revision(), 2);
+    assert_eq!(reloaded.status().state(), MobileWatchSnapshotState::Pending);
+    Ok(())
+}
+
 #[test]
 fn authoritative_context_switches_sender_generation_and_rejects_delayed_packets() -> TestResult {
     let directory = tempfile::tempdir()?;