bug#62720: 29.0.60; Not easy at all to upgrade :core packages like Eglot

[Eli Zaretskii]

> From: Philip Kaludercic <philipk@posteo.net>
> Cc: joaotavora@gmail.com,  monnier@iro.umontreal.ca,  62720@debbugs.gnu.org
> Date: Sat, 15 Apr 2023 13:21:53 +0000
> 
> >> - User option to enable upgrading built-in packages
> >> - Prefix argument to enable upgrading built-in packages
> >> - Always upgrade built-in packages
> >
> > The first two on emacs-29, the last one on master (if enough people
> > think it's a good idea; me, I think we should wait for a while before
> > deciding).
> 
> OK, so let us use this change:
> 
> (I intentionally picked this one without the user option since that
> will probably become unnecessary with Emacs 30+).

The user option allows those users who always want package-install to
upgrade core package to have what they want, easily.  So I think we
should keep it.  On master, the option could be t by default, or
become unnecessary if that's what happens (but I wouldn't bet on
that).

> I believe there was an issue with the name
> `package--upgradable-built-in-p' and the docstring?

Yes.  The doc string has a typo:

  "Return non-nil if PACKAGE if the built-in version is used."

See those two "if"s?  And even if I replace the second "if" with "is",
the sentence doesn't make sense.

As for the name, I think we can leave it at that.

Thanks.