ThreadBroadcastMessageEvent is missing files, upload, display_as_bot and parent_user_id #2762

Package

@slack/types

SDK Version

@slack/types@3.2.0

Node.js Version

N/A (type definition issue)

Operating System

No response

Steps to Reproduce

1. Set up an app subscribed to the message.channels event.
2. Start a thread in a channel where the app is a member.
3. Reply in that thread. Attach a file and check "Also send to #channel".
4. Inspect the payload of the message event the app receives.

In TypeScript, the following code does not compile:

import type { ThreadBroadcastMessageEvent } from "@slack/types";

function handle(event: ThreadBroadcastMessageEvent) {
  event.files; // error TS2339: Property 'files' does not exist on type 'ThreadBroadcastMessageEvent'
}

Expected Result

ThreadBroadcastMessageEvent defines files?: File[], upload?: boolean, display_as_bot?: boolean and parent_user_id?: string. Slack sends these fields, so we can access them without a type assertion.

Actual Result

Slack sends a message event with subtype: "thread_broadcast". The event includes files, upload, display_as_bot and parent_user_id:

{
  "type": "message",
  "subtype": "thread_broadcast",
  "user": "U0XXXXXXX",
  "text": "broadcast with a file",
  "ts": "1791448977.697319",
  "thread_ts": "1791447929.601119",
  "channel": "C0XXXXXXX",
  "channel_type": "channel",
  "event_ts": "1791448977.697319",
  "client_msg_id": "...",
  "parent_user_id": "U0XXXXXXX",
  "display_as_bot": false,
  "upload": false,
  "files": [{ "id": "F0XXXXXXX", "name": "image.png", "filetype": "png", ... }],
  "root": { ... },
  "blocks": [ ... ]
}

However, ThreadBroadcastMessageEvent does not define any of these four fields:

In the same file, GenericMessageEvent defines files and parent_user_id, and FileShareMessageEvent defines all four.