Re: feature/package+vc 04c4c578c7 3/4: Allow for packages to be installed directly from VCS

[Stefan Monnier]

> +     (list (mapcan
> +            (lambda (spec)
> +              (let ((rel (ignore-errors (elpaa--get-last-release spec))))
> +                (when rel
> +                  (nconc spec (list :release-rev (cdr rel)))))
> +              (pcase spec
> +                (`(,name :url nil . ,rest)
> +                 `((,name :url ,(concat "https://git.sv.gnu.org/git/"; 
> elpaa--gitrepo)
> +                          :branch ,(concat elpaa--branch-prefix (car spec))
> +                          ,@rest)))
> +                (`(,_ :core ,_ . ,_) nil)       ;not supported
> +                (_ (list spec))))
> +            specs)
> +           :version 1 :default-vc 'Git)

IMO we should strive to reduce a package's spec.  Ideally they should
just be a URL.  We're not there yet, but the above adds info which we
can (and do in `elpa-admin.el`) extract from the VCS, so it's going
"backward".  IOW, it's making things worse rather than better.


        Stefan