How to properly test the Mail object in rspec -

in reading of rspec, sounds doing like...

expect_any_instance_of(mail).to receive(:deliver) 

...should cause rspec replace deliver method it's own deliver method isn't called. in case when following error in test leads me believe still being called.

 failure/error: task.send_email_alert('test', dummy)      errno::econnrefused:        connection refused - connect(2) "localhost" port 25 

here's method

def send_email_alert(alert_body, alert)   mail = mail.new     alert.send_emails_from     alert.email_address     subject 'new job posted ' + alert.job_board_name     body alert_body   end   mail.deliver! end 

and here's test.

context 'send_email_alert'     'creates email , calls deliver method'       dummy = openstruct.new(send_emails_from: 'test@test.com', job_board_name: 'test', email_address: 'test@test.com')       expect(mail).to receive(:deliver).and_return(true)       task.send_email_alert('test', dummy)     end end 

you've stubbed deliver, did not stub deliver!, method called. separate methods.