Ruby on rails rails mailer在同一邮件中生成html和文本

我在mailer controller中有一个方法，在平台上创建每条消息后发送电子邮件通知

MailerClass.send_mail_notification(to, @conversation).deliver_now

我写了方法，写了视图（用html和纯文本）

然而，当邮件在测试中交付时，纯文本和html版本都放在邮件收集器的同一html选项卡中

----==_mimepart_5e78cae1e1672_73fb2187fbc2829035 Content-Type: text/plain;
 charset=UTF-8 Content-Transfer-Encoding: 7bit # Hi ..., 

======================= 
there was a new message from ... to ...: 
how are you 
Click here to see more: open interview 
----==_mimepart_5e78cae1e1672_73fb2187fbc2829035 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit 
----==_mimepart_5e78cae1e1672_73fb2187fbc2829035 Content-Type: text/html; charset=UTF-8 Content-Transfer-Encoding: 7bit #<InterviewRequest:0x00007f6430a062c0>

Hi ...,
there was a new message ...
---==_mimepart_...

---==\u mimepart\u 5E78CAE1672\u 73fb2187fbc2829035内容类型：文本/普通；
charset=UTF-8内容传输编码：7bit#Hi。。。，
======================= 
有一条新消息来自。。。致……：
你好吗
单击此处查看更多信息：开放式面试
----==\u mimepart\u 5E78CAE1672\u 73fb2187fbc2829035内容类型：文本/普通；字符集=UTF-8内容传输编码：7bit
----==\u mimepart\u 5e78cae1e1672\u 73fb2187fbc289035内容类型：text/html；字符集=UTF-8内容传输编码：7bit#
你好
有一条新消息。。。
---==\u mimepart\u。。。

我注意到，这两种类型的mimepart是相同的。这是否让mailcatcher将这两封邮件识别为同一封邮件？如何为纯文本和html生成不同的mimetype，以便将它们分开

有人有类似的情况或对此有任何想法吗？ 谢谢

----==_mimepart_5e78cae1e1672_73fb2187fbc2829035 Content-Type: text/plain;
 charset=UTF-8 Content-Transfer-Encoding: 7bit # Hi ..., 

======================= 
there was a new message from ... to ...: 
how are you 
Click here to see more: open interview 
----==_mimepart_5e78cae1e1672_73fb2187fbc2829035 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit 
----==_mimepart_5e78cae1e1672_73fb2187fbc2829035 Content-Type: text/html; charset=UTF-8 Content-Transfer-Encoding: 7bit #<InterviewRequest:0x00007f6430a062c0>

Hi ...,
there was a new message ...
---==_mimepart_...