fix: preserve tab identity across restored sessions

1 files changed, 112 insertions, 5 deletions

diff --git a/src/persist/restore.rs b/src/persist/restore.rs
index 229d565d..7c046698 100644
--- a/src/persist/restore.rs
+++ b/src/persist/restore.rs
@@ -509,11 +509,7 @@ fn restore_tab(
             .map(|pane_id| {
                 PaneLaunchEnv::from_extra(Vec::new()).with_identity(
                     workspace_id.to_string(),
-                    format!(
-                        "{}:t{}",
-                        workspace_id,
-                        crate::workspace::encode_public_number(number)
-                    ),
+                    crate::workspace::public_tab_id_for_number(workspace_id, number),
                     pane_id.to_string(),
                 )
             })
@@ -1312,6 +1308,117 @@ mod tests {
         assert_eq!(workspace.next_public_tab_number, 6);
     }
 
+    #[tokio::test]
+    async fn restore_with_gapped_public_tab_numbers_keeps_agent_panel_tab_indices() {
+        let cwd = std::env::current_dir().unwrap();
+        let pane_snap = |id: &str| {
+            (
+                id.parse::<u32>().unwrap(),
+                super::super::snapshot::PaneSnapshot {
+                    cwd: cwd.clone(),
+                    label: None,
+                    agent_name: None,
+                    agent_session: None,
+                    launch_argv: None,
+                },
+            )
+        };
+        let final_pane = super::super::snapshot::PaneSnapshot {
+            cwd: cwd.clone(),
+            label: Some("planner".into()),
+            agent_name: Some("planner".into()),
+            agent_session: Some(super::super::snapshot::PaneAgentSessionSnapshot {
+                source: "herdr:codex".into(),
+                agent: "codex".into(),
+                kind: crate::agent_resume::AgentSessionRefKind::Id,
+                value: "codex-session".into(),
+            }),
+            launch_argv: None,
+        };
+        let snapshot = SessionSnapshot {
+            version: super::super::snapshot::SNAPSHOT_VERSION,
+            workspaces: vec![WorkspaceSnapshot {
+                id: Some("w1".into()),
+                custom_name: None,
+                identity_cwd: cwd.clone(),
+                worktree_space: None,
+                public_pane_numbers: HashMap::from([(10, 1), (11, 2), (12, 3), (13, 4)]),
+                next_public_pane_number: 5,
+                public_tab_numbers: vec![1, 3, 4, 5],
+                next_public_tab_number: 6,
+                tabs: vec![
+                    TabSnapshot {
+                        custom_name: None,
+                        layout: LayoutSnapshot::Pane(10),
+                        panes: HashMap::from([pane_snap("10")]),
+                        zoomed: false,
+                        focused: Some(10),
+                        root_pane: Some(10),
+                    },
+                    TabSnapshot {
+                        custom_name: None,
+                        layout: LayoutSnapshot::Pane(11),
+                        panes: HashMap::from([pane_snap("11")]),
+                        zoomed: false,
+                        focused: Some(11),
+                        root_pane: Some(11),
+                    },
+                    TabSnapshot {
+                        custom_name: None,
+                        layout: LayoutSnapshot::Pane(12),
+                        panes: HashMap::from([pane_snap("12")]),
+                        zoomed: false,
+                        focused: Some(12),
+                        root_pane: Some(12),
+                    },
+                    TabSnapshot {
+                        custom_name: None,
+                        layout: LayoutSnapshot::Pane(13),
+                        panes: HashMap::from([(13, final_pane)]),
+                        zoomed: false,
+                        focused: Some(13),
+                        root_pane: Some(13),
+                    },
+                ],
+                active_tab: 3,
+            }],
+            active: Some(0),
+            selected: 0,
+            agent_panel_scope: Default::default(),
+            sidebar_width: None,
+            sidebar_section_split: None,
+            collapsed_space_keys: Default::default(),
+        };
+        let (events, _event_rx) = mpsc::channel(4);
+
+        let (workspaces, terminals, _runtimes) = restore(
+            &snapshot,
+            None,
+            24,
+            80,
+            0,
+            test_restore_shell(),
+            crate::config::ShellModeConfig::NonLogin,
+            false,
+            events,
+            Arc::new(Notify::new()),
+            Arc::new(AtomicBool::new(false)),
+        );
+
+        let workspace = workspaces.first().expect("workspace should restore");
+        let agent_pane = workspace.tabs[3].root_pane;
+        let detail = workspace
+            .pane_details(&terminals)
+            .into_iter()
+            .find(|detail| detail.pane_id == agent_pane)
+            .expect("restored agent pane should be listed");
+
+        assert_eq!(workspace.active_tab, 3);
+        assert_eq!(workspace.tabs[3].number, 5);
+        assert_eq!(detail.tab_idx, 3);
+        assert_eq!(detail.agent_label, "planner");
+    }
+
     #[test]
     fn legacy_restore_precomputes_missing_public_pane_numbers() {
         let cwd = std::env::current_dir().unwrap();