app-server: test empty workspace roots roundtrip

codex-rs/app-server/src/request_processors/thread_processor_tests.rs

@@ -547,6 +547,49 @@ mod thread_processor_behavior_tests {
         assert_eq!(persisted.workspace_roots, vec![workspace_root]);
     }
 
+    #[test]
+    fn persisted_thread_permission_state_preserves_empty_workspace_roots_from_event_roundtrip() {
+        let cwd = test_path_buf("/tmp/project").abs();
+        let thread_id = ThreadId::from_string("67e55044-10b1-426f-9247-bb680e5fe0c8").unwrap();
+        let permission_profile = codex_protocol::models::PermissionProfile::workspace_write();
+        let event = codex_protocol::protocol::EventMsg::SessionConfigured(
+            codex_protocol::protocol::SessionConfiguredEvent {
+                session_id: thread_id.into(),
+                thread_id,
+                forked_from_id: None,
+                thread_source: None,
+                thread_name: None,
+                model: "gpt-5".to_string(),
+                model_provider_id: "mock_provider".to_string(),
+                service_tier: None,
+                approval_policy: AskForApproval::Never,
+                approvals_reviewer: codex_protocol::config_types::ApprovalsReviewer::User,
+                permission_profile: permission_profile.clone(),
+                active_permission_profile: None,
+                cwd: cwd.clone(),
+                workspace_roots: Vec::new(),
+                reasoning_effort: None,
+                initial_messages: None,
+                network_proxy: None,
+                rollout_path: None,
+            },
+        );
+        let event = serde_json::from_value(serde_json::to_value(event).unwrap()).unwrap();
+        let history = codex_protocol::protocol::InitialHistory::Forked(vec![
+            codex_protocol::protocol::RolloutItem::EventMsg(event),
+        ]);
+
+        let persisted = persisted_thread_permission_state(
+            &history,
+            Some(cwd.as_path()),
+            /*fallback_sandbox_policy*/ None,
+        )
+        .expect("permission state should be reconstructed");
+
+        assert_eq!(persisted.permission_profile, permission_profile);
+        assert_eq!(persisted.workspace_roots, Vec::<AbsolutePathBuf>::new());
+    }
+
     #[test]
     fn config_load_error_marks_cloud_requirements_failures_for_relogin() {
         let err = std::io::Error::other(CloudRequirementsLoadError::new(