`sendResponse`, the 3rd param of `addListener` callback function accepts expected 1 param in `any` type but 0 now

[Yang Zihan]

As I expected, the sendResponse callback should accept 1 param in any type but now 0.

Thus the following codes will fail to pass the type checking.

[Rob]

The type should be something like sendResponse: (response?: any) => void

The types are generated automatically so how do we fix this?

[Matt McNally]

This appears to affect not just runtime.onMessage but also runtime.onMessageExternal and runtime.onUserScriptMessage. The invalid definition originates from Chrome's documentation: https://developer.chrome.com/docs/extensions/reference/api/runtime#event-onMessage - an override might be needed here to enforce inclusion of a response argument.

[Aniruddha Mukherjee]

According to MDN:

The function takes a single argument, which may be any serializable object

So sendResponse(response: any) => void should do the trick right?

And why isn't this issue fixed yet? This seems like a longstanding problem.

[Rob]

I think someone who works at Google will have to fix it.

[Oleh]

I have fixed this localy using declaration merging. Hope this helps someone.

declare namespace chrome {
  /// <reference types="chrome-types" />
  export namespace runtime {
    export const onMessage: events.Event<
      (
        message: any,
        sender: MessageSender,
        sendResponse: (data: any) => void,
      ) => boolean | undefined
    >;
  }
}