update

src/main/java/com/gogirl/application/product/mall/impl/MallCategoryServiceImpl.java

@@ -40,7 +40,10 @@ public class MallCategoryServiceImpl extends ServiceImpl<CategoryMapper, MallCat
         for (MallCategory mallCategory : list) {
             if (mallCategory.getId().equals(subTreeId)) {
                 if (ListUtil.isNotEmpty(mallCategory.getChildList())) {
-                    return SerializationUtils.clone((new ArrayList<>(mallCategory.getChildList())));
+                    List<MallCategory> clone = SerializationUtils.clone((new ArrayList<>(mallCategory.getChildList())));
+                    if (ListUtil.isNotEmpty(clone)) {
+                        return clone;
+                    }
                 }
             } else if (ListUtil.isNotEmpty(mallCategory.getChildList())) {
                 this.findSubTree(mallCategory.getChildList(), subTreeId);