Re: Stability of core packages (was: Not easy at all to upgrade :core packages like Eglot)

[Eli Zaretskii <eliz@gnu.org>]

> From: "Dr. Arne Babenhauserheide" <arne_bab@web.de>
> Cc: joaotavora@gmail.com, jporterbugs@gmail.com, dmitry@gutov.dev,
>  emacs-devel@gnu.org
> Date: Wed, 19 Apr 2023 21:40:35 +0200
> 
> > Specifically, users of Emacs 28 and older, who had Eglot installed,
> > and expect Eglot to be automatically updated upon Emacs startup
> > whenever a new Eglot version is available, will now have their
> > expectations broken after they upgrade to Emacs 29, because Eglot is
> > now a built-in package, and package.el won't by default upgrade a
> > built-in package.
> …
> > So there's a dilemma here: which of the two groups of users to break?
> 
> Not updating eglot until the next Emacs release shouldn’t cause breakage
> in any other packages, right?

No, it shouldn't.  With the obvious exception of the breakage that is
already part of the current Emacs release, which we somehow failed to
detect and fix before releasing it.

> Except if a more modern eglot is a dependency of a non-built-in package.

Right.

> I think that’s what I would prefer: I would treat being pulled into
> Emacs as a stabilization step that switches the package from being on
> the latest version to being at the version in Emacs or the minimum
> version required by dependencies — if that version is higher than the
> version in Emacs. Basically minimize the distance from the Emacs
> release.

AFAIU, that is what will happen with Emacs 29 when it is released.
But things might change in Emacs 30, as we are currently discussing
what needs to be done to better support updating core packages.