class Capybara::RackTest::Form

def add_input_param(field, params)
  if %w[radio checkbox].include? field['type']
    if field['checked']
      node = Capybara::RackTest::Node.new(driver, field)
      merge_param!(params, field['name'].to_s, node.value.to_s)
    end
  elsif %w[submit image].include? field['type']
    # TODO: identify the click button here (in document order, rather
    # than leaving until the end of the params)
  elsif field['type'] == 'file'
    if multipart?
      file = if (value = field['value']).to_s.empty?
        NilUploadedFile.new
      else
        mime_info = MiniMime.lookup_by_filename(value)
        Rack::Test::UploadedFile.new(value, (mime_info && mime_info.content_type).to_s)
      end
      merge_param!(params, field['name'].to_s, file)
    else
      merge_param!(params, field['name'].to_s, File.basename(field['value'].to_s))
    end
  else
    merge_param!(params, field['name'].to_s, field['value'].to_s)
  end
end