bug#62044: 30.0.50; ERC 5.5: Auto-reconnect is broken

[J.P.]

"J.P." <jp@neverwas.me> writes:

> A stop-gap solution for this issue was introduced in ERC 5.6 as
> `erc-server-delayed-check-reconnect', a new function value for the
> option `erc-server-reconnect-function'. There's since been some
> criticism regarding its lack of discoverability, despite it featuring in
> the Sample Configuration of ERC's manual. It's therefore been suggested
> we favor the behavior it enables whenever possible by detecting
> compatible values of `erc-server-connect-function'. Any false negatives
> will hopefully only affect advanced users with nonstandard connectors.
> The following patch tries to implement this. Feedback welcome.

I ended up installing this (perhaps only temporarily) as

  https://git.savannah.gnu.org/cgit/emacs.git/commit/?id=1c960bda

At the end of the day, I still question the soundness of resorting to a
protocol exchange to prove that the underlying transport is functioning
properly. However, if no one complains in the next week or two, I'll
close this with the release of 5.6.1.

Thanks.