cucumber - attach_file 不工作。在黄瓜我得到这个错误

Question

我收到这个错误

"undefined method `attach_file' for #<Object:0x00000002016970> (NoMethodError)"

对于我拥有的代码：-

When /^(?:|I )attach the file "([^\"]*)" to "([^\"]*)"(?: within "([^\"]*)")?$/ do |path, field, selector|

    attach_file(field, path)


end