Creating Spend Info from Tree sturcture

create_spend_info.rs

// Some user struct for trees
enum Tree {
  Node(Tree,Tree),
  Leaf(Miniscript),
}

impl Tree {

  fn update_builder(&self, builder: TaprootBuilder, depth: usize) -> TaprootBuilder {
    match self { 
     Leaf(ms) => builder.add_leaf(ms, depth),
     Node(a, b) => {
        builder = a.update_builder(builder, depth + 1);
        b.update_builder(builder, depth + 1)
      }
    }
  }
}

root.update_builder(&mut new_builder, 0);