class Opal::Nodes::CallNode::DependencyResolver

def expand_path(path, base = '')
  "#{base}/#{path}".split('/').each_with_object([]) do |part, p|
    if part == ''
      # we had '//', so ignore
    elsif part == '..'
      p.pop
    else
      p << part
    end
  end.join '/'
end