Description

Concerning TypeScript, there seems to be a mismatch between message event type definitions and the actual events from Slack. For instance the following example would cause unexpected errors due to message_changed events:

app.message(({ message }) => {
  const user: string = message.user
  if (user.match(/^U/)) {
    // ...
  }
})

The type definition does not allow message.user to be undefined, but in reality it may be when the subtype is message_changed. This issue is easy to work around by filtering by subtype, but these type safety breaking issues can be fiendishly difficult to detect.

What type of issue is this?

• bug
• enhancement (feature request)
• question
• documentation related
• testing related
• discussion

Requirements

• I've read and understood the Contributing guidelines and have done my best effort to follow them.
• I've read and agree to the Code of Conduct.
• I've searched for any related issues and avoided creating a duplicate issue.