
fn split_file(data: FileSlice) -> io::Result<(FileSlice, FileSlice)> {
    let (data, footer_len_bytes) = data.split_from_end(size_of::<u64>());
    let serialized_offset: OwnedBytes = footer_len_bytes.read_bytes()?;
    let mut serialized_offset_buf = serialized_offset.as_slice();
    let offset = u64::deserialize(&mut serialized_offset_buf)? as usize;
    Ok(data.split(offset))
}

#[cfg(test)]