context_hasher.update(b"\0");

        context_hasher.update(b"\0");

    vertices[v].context_path = Some(Arc::new(
        store_path.join(data_encoding::HEXLOWER.encode(context_hasher.finalize().as_bytes())),
    ));

    let s = data_encoding::HEXLOWER.encode(context_hasher.finalize().as_bytes());
    vertices[v].context_path = Some(Arc::new(store_path.join(s)));

async fn copy(from: &Path, to: &Path) -> Result<(), std::io::Error> {

async fn copy(
    hashing: &mut Vec<tokio::task::JoinHandle<Result<Option<(PathBuf, String)>, Error>>>,
    from: &Path,
    to: &Path,
) -> Result<(), std::io::Error> {

            if p == Path::new("blake3sums") {
                continue;
            }

            tokio::fs::hard_link(&elt, &to.join(&p)).await.unwrap_or(());

            let to_p = to.join(&p);
            tokio::fs::hard_link(&elt, &to_p).await.unwrap_or(());
            let p = p.to_path_buf();
            hashing.push(tokio::spawn(async move {
                // hash + write
                info!("hashing {:?}", to_p);
                if let Ok(file) = tokio::fs::File::open(&to_p).await {
                    let mut hasher = blake3::Hasher::new();
                    hash_reader(file, &mut hasher).await.unwrap();
                    let hex = data_encoding::HEXLOWER.encode(hasher.finalize().as_bytes());
                    Ok::<_, Error>(Some((p, hex)))
                } else {
                    Ok(None)
                }
            }));

    let mut hashing = Vec::new();

                    copy(&vertices[d].context_path.clone().unwrap(), &tmp.dir_path()).await?

                    copy(
                        &mut hashing,
                        &vertices[d].context_path.clone().unwrap(),
                        &tmp.dir_path(),
                    )
                    .await?;

    let mut hashing = Vec::new();

        let f = rel.to_path_buf();

            let path = path
                .strip_prefix(&vertices[v].downloaded.path)
                .unwrap()
                .to_str()
                .unwrap();

            let path = path.to_str().unwrap();