diff --git a/markbase-core/src/vfs/local_fs.rs b/markbase-core/src/vfs/local_fs.rs
index 75092a6..651ea99 100644
--- a/markbase-core/src/vfs/local_fs.rs
+++ b/markbase-core/src/vfs/local_fs.rs
@@ -771,3 +771,118 @@ impl VfsAclMeta {
         }
     }
 }
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+    use std::fs;
+    use std::time::Duration;
+    use tempfile::TempDir;
+
+    fn setup_snapshots(base_dir: &Path, snapshot_name: &str) -> PathBuf {
+        let snapshots_dir = base_dir.join(".snapshots");
+        let snapshot_path = snapshots_dir.join(snapshot_name);
+
+        fs::create_dir_all(&snapshot_path).unwrap();
+
+        let meta = VfsSnapshotMeta {
+            name: snapshot_name.to_string(),
+            created: SystemTime::now(),
+            source_path: base_dir.to_string_lossy().to_string(),
+        };
+
+        let meta_file = snapshot_path.join(".meta");
+        let meta_json = serde_json::to_string(&meta).unwrap();
+        fs::write(&meta_file, &meta_json).unwrap();
+
+        snapshot_path
+    }
+
+    #[test]
+    fn test_list_previous_versions_with_snapshot() {
+        let temp_dir = TempDir::new().unwrap();
+        let fs_backend = LocalFs::new();
+
+        setup_snapshots(temp_dir.path(), "snapshot_1");
+
+        let versions = fs_backend.list_previous_versions(temp_dir.path()).unwrap();
+        assert_eq!(versions.len(), 1);
+
+        let version = &versions[0];
+        assert_eq!(version.snapshot_name, "snapshot_1");
+        assert!(version.gmt_token.starts_with("@GMT-"));
+    }
+
+    #[test]
+    fn test_list_previous_versions_multiple() {
+        let temp_dir = TempDir::new().unwrap();
+        let fs_backend = LocalFs::new();
+
+        setup_snapshots(temp_dir.path(), "snapshot_1");
+        std::thread::sleep(Duration::from_secs(2));
+        setup_snapshots(temp_dir.path(), "snapshot_2");
+
+        let versions = fs_backend.list_previous_versions(temp_dir.path()).unwrap();
+        assert_eq!(versions.len(), 2);
+    }
+
+    #[test]
+    fn test_open_previous_version_not_found() {
+        let temp_dir = TempDir::new().unwrap();
+        let fs_backend = LocalFs::new();
+
+        let result = fs_backend.open_previous_version(temp_dir.path(), "@GMT-2021.01.01-00.00.00");
+        assert!(result.is_err());
+    }
+
+    #[test]
+    fn test_list_previous_versions_empty() {
+        let temp_dir = TempDir::new().unwrap();
+        let fs_backend = LocalFs::new();
+
+        let versions = fs_backend.list_previous_versions(temp_dir.path()).unwrap();
+        assert_eq!(versions.len(), 0);
+    }
+
+    #[test]
+    fn test_gmt_token_unique() {
+        let temp_dir = TempDir::new().unwrap();
+
+        setup_snapshots(temp_dir.path(), "snapshot_1");
+        std::thread::sleep(Duration::from_secs(2));
+        setup_snapshots(temp_dir.path(), "snapshot_2");
+
+        let fs_backend = LocalFs::new();
+        let versions = fs_backend.list_previous_versions(temp_dir.path()).unwrap();
+
+        let gmt_tokens: Vec<&str> = versions.iter().map(|v| v.gmt_token.as_str()).collect();
+        assert_ne!(gmt_tokens[0], gmt_tokens[1]);
+    }
+
+    #[test]
+    fn test_skip_hidden_snapshots() {
+        let temp_dir = TempDir::new().unwrap();
+        let fs_backend = LocalFs::new();
+
+        setup_snapshots(temp_dir.path(), "snapshot_1");
+
+        let hidden_snapshot_path = temp_dir.path().join(".snapshots").join(".hidden");
+        fs::create_dir_all(&hidden_snapshot_path).unwrap();
+
+        let versions = fs_backend.list_previous_versions(temp_dir.path()).unwrap();
+        assert_eq!(versions.len(), 1);
+    }
+
+    #[test]
+    fn test_snapshot_meta_parse() {
+        let temp_dir = TempDir::new().unwrap();
+
+        let snapshot_path = setup_snapshots(temp_dir.path(), "test_snapshot");
+
+        let meta_file = snapshot_path.join(".meta");
+        let meta_json = fs::read_to_string(&meta_file).unwrap();
+        let meta: VfsSnapshotMeta = serde_json::from_str(&meta_json).unwrap();
+
+        assert_eq!(meta.name, "test_snapshot");
+    }
+}