local snippet = contents:sub(math.max(1, index-100), math.min(#contents, index+100))

      local start_offset = find_previous_byte(contents, '\n', index)
      local end_offset = contents:find('\n', index, --[[literal]] true)
      local snippet = contents:sub(start_offset, end_offset)

  end
end
function find_previous_byte(s, b, index)
  while index > 1 do
    if s:sub(index, index) == b then
      break
    end
    index = index-1

  return index