fn is_alive_or_zombie<T: GraphTxnT>(
    txn: &T,
    channel: &T::Graph,
    a: &Vertex<ChangeId>,
) -> Result<bool, TxnErr<T::GraphError>> {
    if a.is_root() {
        return Ok(true);
    }
    for e in iter_adjacent(
        txn,
        channel,
        *a,
        EdgeFlags::PARENT,
        EdgeFlags::all() - EdgeFlags::DELETED,
    )? {
        let e = e?;
        let zf = EdgeFlags::pseudof();
        if (e.flag() & zf != EdgeFlags::PSEUDO)
            && (e.flag().contains(EdgeFlags::BLOCK) || a.is_empty())
        {
            return Ok(true);
        }
    }
    Ok(false)
}

                let is_dead = parent_is_dead || {
                    if let Some(vertex) = txn.get_inodes(&inode_, None)? {
                        vertex.change != pending_change_id
                            && !is_alive(txn, channel, &vertex.inode_vertex())?
                    } else {
                        true
                    }
                };

                let is_dead = parent_is_dead
                    || (!id.basename.is_empty() && {
                        if let Some(vertex) = txn.get_inodes(&inode_, None)? {
                            vertex.change != pending_change_id
                                && !is_alive_or_zombie(txn, channel, &vertex.inode_vertex())?
                        } else {
                            true
                        }
                    });