_app. componentDidCatch is deprecated in upcoming v9.3.7 - Is the Sentry example still valid?

[Vadorequest]

I've noticed the componentDidCatch method is now deprecated.

https://github.com/zeit/next.js/blob/v9.3.7-canary.12/packages/next/pages/_app.tsx#L38

But, it's still used in the with-sentry example:
https://github.com/zeit/next.js/blob/18a9c7e371efc4c487f9c3599c3211ce30009d6c/examples/with-sentry/pages/_app.js#L50

Should we stop using it? I'm wondering because I'm also using Sentry with the following code:

  componentDidCatch(error: Error, errorInfo: ErrorInfo): void {
    // eslint-disable-next-line no-console
    console.debug('_app.componentDidCatch - Unexpected error caught', error, errorInfo);

    Sentry.withScope((scope) => {
      Object.keys(errorInfo).forEach((key) => {
        scope.setExtra(key, errorInfo[key]);
      });

      Sentry.captureException(error);
    });

    // This is needed to render errors correctly in development / production
    super.componentDidCatch(error, errorInfo);
  }

Is the above way outdated?
Do you recommend a new way of catching errors as of Next.js 9.3.6?

[timneutkens]

It's actually not using that method, using componentDidCatch is fine in any component. What was deprecated is having to call super.componentDidCatch (calling the built-in _app componentDidCatch) as that does not do anything special anymore.

So in case of your example you can remove super.componentDidCatch and replace it with throw error as that makes it bubble up the error again.

[Vadorequest]

Thanks @timneutkens, I've actually removed componentDidCatch in _app altogether, I don't see the point anymore. I don't remember why it was necessary in the first place. Errors in _app are properly caught and display the _error page as expected, so it doesn't seem necessary to keep it around.

Unless I've missed something?

[timneutkens]

Correct! We just catch them and render _error indeed 👍

[Vadorequest]

Awesome, this simplifies things a bit.

I have other error-related questions at #12913 (with focus on SSG/hybrid rendering and concerns), if ever you find some time.

I'm also rewriting a v9.2 app into a v9.4 with SSG first-class support at https://github.com/UnlyEd/next-right-now/tree/v1-hyb-mst-aptd-gcms-lcz-sty, I'd love if someone from the Next.js core team could review it and give us some feedback on it (perfs, best practices, etc.)

Thank you for this very great framework. <3