title: Testing ActionMailer multipart emails(text and html version) with RSpec
body: <p>I'm currently testing my mailers with RSpec, but I've started setting up multipart emails as described in the Rails Guides here:  <a href="http://guides.rubyonrails.org/action_mailer_basics.html#sending-multipart-emails" rel="noreferrer">http://guides.rubyonrails.org/action_mailer_basics.html#sending-multipart-emails</a></p>
  
  <p>I have both mailer templates in text and html formats, but it looks like my tests are only checking the HTML portion.  Is there a way to check the text template separately?</p>
  
  <p>Is it only checking the HTML view because it's first in the default order?</p>