I have an actionmailer class and associated overhead, it works perfectly. In my unit test (rails default minitest) however, the email body is empty. Why is that?
my mail
You probably have two versions of the email templates (text.erb and html.erb).
text.erb
html.erb
If so, you can use email.text_part.body.to_s for plain-text email and email.html_part.body.to_s for HTML version.
email.text_part.body.to_s
email.html_part.body.to_s