SiteSetting.disable_emails로 인해 메시지가 전송되지 않는 문제를 재현하지는 못했지만, EmailLog가 반환된 경우에만 성공으로 보고하도록 스크립트를 수정했고, disable_emails 설정에 대한 추가 경고도 추가했습니다.
$ bin/rake 'emails:test[]'
Testing sending to using localhost:1025, username: with auth.
SMTP server connection successful.
Sending to . . .
Mail was not sent.
Reason: message.to is blank
### WARNING
The `disable_emails` site setting is currently set to non-staff.
Consider changing it to 'no' before performing any further troubleshooting.
그리고
Sending to michael@example.com. . .
Mail accepted by SMTP server.
Message-ID: dfaf1c88-aab6-474b-b50c-8c500afb6291@localhost
If you do not receive the message, check your SPAM folder
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