use git cli when available and fallback to libgit2 about ffizer HOT 1 CLOSED

#[tracing::instrument(fields(dst = ?dst.as_ref(), url = url.as_ref(), rev = rev.as_ref()))]
#[cfg(not(feature = "git2"))]
pub fn retrieve<P, U, R>(dst: P, url: U, rev: R) -> Result<(), Error>
where
    P: AsRef<Path>,
    R: AsRef<str>,
    U: AsRef<str>,
{
    let dst = dst.as_ref();
    if dst.exists() {
        // fetch
        debug!("fetch origin");
        let _fetch_result = std::process::Command::new("git")
            .args(["fetch", "origin"])
            .status()?;

        // checkout
        debug!("checkout --force {}", rev.as_ref());
        let _checkout_result = std::process::Command::new("git")
            .args(["checkout", "--force", rev.as_ref()])
            .status()?;

        // reset
        debug!("reset --hard origin/{}", rev.as_ref());
        let remote_branch = format!("origin/{}", rev.as_ref());
        let _checkout_result = std::process::Command::new("git")
            .args(["reset", "--hard", remote_branch.as_str()])
            .status()?;
    } else {
        std::fs::create_dir_all(dst).map_err(|source| Error::CreateFolder {
            path: dst.to_path_buf(),
            source,
        })?;

        // clone
        let git_url = dst.as_os_str().to_str().unwrap();
        debug!("clone --branch {} {}", rev.as_ref(), git_url);
        let _clone_result = std::process::Command::new("git")
            .args(["clone", "--branch", rev.as_ref(), git_url])
            .status()?;

        // checkout
        debug!("checkout --force {}", rev.as_ref());
        let _checkout_result = std::process::Command::new("git")
            .args(["checkout", "--force", rev.as_ref()])
            .status()?;
    }
    Ok(())
}