You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: ls_tree.rs
    path of file: ./repos/turbo/crates/turborepo-scm/src
    
    the code of the file until where you have to start completion: use std::{
    io::{BufRead, BufReader, Read},
    process::{Command, Stdio},
};

use nom::Finish;
use turbopath::{AbsoluteSystemPathBuf, RelativeUnixPathBuf};

use crate::{package_deps::GitHashes,
    
    pub fn git_ls_tree(&self, root_path: &AbsoluteSystemPathBuf) -> Result<GitHashes, Error> {
        let mut hashes = GitHashes::new();
        let mut git = Command::new(self.bin.as_std_path())
            .args(["ls-tree", "-r", "-z", "HEAD"])
            .current_dir(root_path)
            .stdout(Stdio::piped())
            .stderr(Stdio::piped())
            .spawn()?;

        let stdout = git
            .stdout
            .as_mut()
            .ok_or_else(|| Error::git_error("failed to get stdout for git ls-tree"))?;
        let mut stderr = git
            .stderr
            .take()
            .ok_or_else(|| Error::git_error("failed to get stderr for git ls-tree"))?;
        let parse_result = read_ls_tree(stdout, &mut hashes);
        wait_for_success(git, &mut stderr, "git ls-tree", root_path, parse_result)?;
        Ok(hashes)
    }