feat: TUI undo op (#5629)

codex-rs/tui/src/chatwidget/tests.rs

@@ -34,6 +34,8 @@ use codex_core::protocol::ReviewRequest;
 use codex_core::protocol::StreamErrorEvent;
 use codex_core::protocol::TaskCompleteEvent;
 use codex_core::protocol::TaskStartedEvent;
+use codex_core::protocol::UndoCompletedEvent;
+use codex_core::protocol::UndoStartedEvent;
 use codex_core::protocol::ViewImageToolCallEvent;
 use codex_protocol::ConversationId;
 use codex_protocol::plan_tool::PlanItemArg;
@@ -294,8 +296,6 @@ fn make_chatwidget_manual() -> (
         suppress_session_configured_redraw: false,
         pending_notification: None,
         is_review_mode: false,
-        ghost_snapshots: Vec::new(),
-        ghost_snapshots_disabled: false,
         needs_final_message_separator: false,
         last_rendered_width: std::cell::Cell::new(None),
         feedback: codex_feedback::CodexFeedback::new(),
@@ -849,6 +849,90 @@ fn slash_init_skips_when_project_doc_exists() {
     );
 }
 
+#[test]
+fn slash_undo_sends_op() {
+    let (mut chat, mut rx, _op_rx) = make_chatwidget_manual();
+
+    chat.dispatch_command(SlashCommand::Undo);
+
+    match rx.try_recv() {
+        Ok(AppEvent::CodexOp(Op::Undo)) => {}
+        other => panic!("expected AppEvent::CodexOp(Op::Undo), got {other:?}"),
+    }
+}
+
+#[test]
+fn undo_success_events_render_info_messages() {
+    let (mut chat, mut rx, _op_rx) = make_chatwidget_manual();
+
+    chat.handle_codex_event(Event {
+        id: "turn-1".to_string(),
+        msg: EventMsg::UndoStarted(UndoStartedEvent {
+            message: Some("Undo requested for the last turn...".to_string()),
+        }),
+    });
+    assert!(
+        chat.bottom_pane.status_indicator_visible(),
+        "status indicator should be visible during undo"
+    );
+
+    chat.handle_codex_event(Event {
+        id: "turn-1".to_string(),
+        msg: EventMsg::UndoCompleted(UndoCompletedEvent {
+            success: true,
+            message: None,
+        }),
+    });
+
+    let cells = drain_insert_history(&mut rx);
+    assert_eq!(cells.len(), 1, "expected final status only");
+    assert!(
+        !chat.bottom_pane.status_indicator_visible(),
+        "status indicator should be hidden after successful undo"
+    );
+
+    let completed = lines_to_single_string(&cells[0]);
+    assert!(
+        completed.contains("Undo completed successfully."),
+        "expected default success message, got {completed:?}"
+    );
+}
+
+#[test]
+fn undo_failure_events_render_error_message() {
+    let (mut chat, mut rx, _op_rx) = make_chatwidget_manual();
+
+    chat.handle_codex_event(Event {
+        id: "turn-2".to_string(),
+        msg: EventMsg::UndoStarted(UndoStartedEvent { message: None }),
+    });
+    assert!(
+        chat.bottom_pane.status_indicator_visible(),
+        "status indicator should be visible during undo"
+    );
+
+    chat.handle_codex_event(Event {
+        id: "turn-2".to_string(),
+        msg: EventMsg::UndoCompleted(UndoCompletedEvent {
+            success: false,
+            message: Some("Failed to restore workspace state.".to_string()),
+        }),
+    });
+
+    let cells = drain_insert_history(&mut rx);
+    assert_eq!(cells.len(), 1, "expected final status only");
+    assert!(
+        !chat.bottom_pane.status_indicator_visible(),
+        "status indicator should be hidden after failed undo"
+    );
+
+    let completed = lines_to_single_string(&cells[0]);
+    assert!(
+        completed.contains("Failed to restore workspace state."),
+        "expected failure message, got {completed:?}"
+    );
+}
+
 /// The commit picker shows only commit subjects (no timestamps).
 #[test]
 fn review_commit_picker_shows_subjects_without_timestamps() {