misskey "register_note_post_interruptor" makes unexpected error in Misskey 12.120.0-alpha.8

💡 Summary

New Deep-Copy function copies null fields when sending notes, that causing errors on API endpoints.

🥰 Expected Behavior

Notes should be sent with no error in while using register_note_post_interruptor

🤬 Actual Behavior

When a note is sent via API, it should be remove null in the nullable field, but if register_note_post_interruptor is used, null is not removed from the request body.

If it's normal, make a request like this: (no polls, no media, no CW, not a reply or renote quote.)

{"text":"Test Text", "poll":null, "localOnly":false, "visibility":"home", "i":"token"}

But it works like this:

{"text":"Test Text", "fileIds":null, "replyId":null, "renoteId":null ,"channelId":null, "poll":null, "cw":null, "localOnly":false, "visibility":"home", "visibleUserIds":null, "i":"token"}

This causes a null to enter a non-nullable field and causes an API error that prevents the note from being sent properly.

Its seems to be a problem caused by the new Deep-Copy function instead of the Deep-Copy usede before by Misskey. The existing JSON.parse(JSON.stringfiy()) deletes the null field of the structure during the parsing process, but the new function copies the null field without deleting it.

That problem causes the interruptor.handler function in MkPostForm to deep-copy a structure containing null to return a value containing null. This causes error in API Endpoint with non-nullable field, so backend returns an error.

📝 Steps to Reproduce

Install and use a plugin that uses register_note_post_interruptor

### {
  id: "shxmwkehdRhflakf"
  name: "auto footer plugin"
  version: "1.0.0"
  author:  "@[email protected]"
  description: "Add footer automatically in notes."
  permissions: []
  config: {
    footer: {
      type: "string"
      label: "Footer"
      description: "Add a footer automatically after the double line break."
      default: ""
    }
  }
}

@note_with_footer(note) {
  #footer = Plugin:config.footer
  note.text <- `{note.text}{Str:lf}{Str:lf}{footer}`
  note
}

Plugin:register_note_post_interruptor(note_with_footer)

Its make error like this:

📌 Environment

Misskey version: Misskey 12.120.0-alpha.8 Your OS: Microsoft Windows 11 Home Insider Preview (25236.1010) Your browser: Mozilla Firefox Nightly 109.0a1