bug#70958: 30.0.50; eglot-managed-mode hooks not called on shutdown

[Eli Zaretskii]

> From: Troy Brown <brownts@troybrown.dev>
> Date: Wed, 15 May 2024 08:38:28 -0400
> 
> The documentation for eglot-managed-mode-hook indicates that the hook
> is run after Eglot has started/stopped managing a buffer.  I was
> trying to use this to perform setup/teardown of functionality when
> this happened, but it appears the registered hooks are never called on
> shutdown.  The following is a little test that can be run in a buffer
> which has LSP support, to demonstrate the problem.  My expectation is
> that "Buffer not managed" is output and the my-eglot-hook-var is
> changed to 'not-managed when a shutdown occurs.
> 
> --8<---------------cut here---------------start------------->8---
> (defun my-eglot-test ()
>   (defun my-eglot-hook ()
>     (message "my-eglot-hook invoked")
>     (if (eglot-managed-p)
>         (progn
>           (message "Buffer is managed")
>           (setq-local my-eglot-hook-var 'managed))
>       (message "Buffer not managed")
>       (setq-local my-eglot-hook-var 'not-managed)))
>   (add-hook 'eglot-managed-mode-hook #'my-eglot-hook)
>   (setq-local my-eglot-hook-var 'initial)
>   (cl-assert (not (eglot-managed-p)))
>   (cl-assert (eq my-eglot-hook-var 'initial))
>   (call-interactively #'eglot)
>   (cl-assert (eglot-managed-p))
>   (cl-assert (eq my-eglot-hook-var 'managed))
>   (sleep-for 3) ; wait for server connection
>   (call-interactively #'eglot-shutdown)
>   (cl-assert (not (eglot-managed-p)))
>   (cl-assert (eq my-eglot-hook-var 'not-managed)))
> --8<---------------cut here---------------end--------------->8---

João, any comments or suggestions?