fix: preserve session layouts across shutdown and restore failures (#4400)

* fix: preserve session layouts across shutdown and restore failures

refs #4320

* test: update subscription fixture for pane restore errors

---------

Co-authored-by: JJ Liebig <jonathan.liebig@gmail.com>

1 files changed, 32 insertions, 0 deletions

diff --git a/src/server/headless/tests/mod.rs b/src/server/headless/tests/mod.rs
index 60f89d63..cf6d389b 100644
--- a/src/server/headless/tests/mod.rs
+++ b/src/server/headless/tests/mod.rs
@@ -96,6 +96,7 @@ fn test_headless_server_with_event_hub(event_hub: api::EventHub) -> HeadlessServ
         headless_size,
         effective_size: headless_size,
         shutting_down: false,
+        host_shutdown_requested: Arc::new(AtomicBool::new(false)),
         handoff_in_progress: false,
         #[cfg(unix)]
         pending_handoff_repaint_nudge: false,
@@ -4186,6 +4187,37 @@ fn changed_git_refresh_requests_headless_render() {
 }
 
 #[tokio::test]
+async fn host_shutdown_preserves_panes_from_queued_and_selected_death_events() {
+    let mut server = test_headless_server();
+    let workspace = crate::workspace::Workspace::test_new("host-shutdown");
+    let pane_id = workspace.tabs[0].root_pane;
+    server.app.state.workspaces = vec![workspace];
+    server.app.state.ensure_test_terminals();
+    server.app.state.active = Some(0);
+    let event = || AppEvent::PaneDied {
+        pane_id,
+        exit_reason: crate::platform::ChildExitReason::Exited,
+    };
+    server.app.event_tx.try_send(event()).unwrap();
+    server
+        .host_shutdown_requested
+        .store(true, Ordering::Release);
+    assert_eq!(
+        server.drain_internal_events_with_forwarding_up_to(16),
+        (false, false)
+    );
+    assert!(!server.handle_internal_event_with_forwarding(event()));
+    assert!(server.app.find_pane(pane_id).is_some());
+    assert!(server.app.event_rx.try_recv().is_ok());
+    server
+        .host_shutdown_requested
+        .store(false, Ordering::Release);
+    assert!(server.handle_internal_event_with_forwarding(event()));
+    assert!(server.app.find_pane(pane_id).is_none());
+    shutdown_test_runtimes(&mut server);
+}
+
+#[tokio::test]
 async fn pane_death_reconciles_each_client_view_and_focus() {
     let mut server = test_headless_server();
     let mut workspace = crate::workspace::Workspace::test_new("pane-death-views");