Hi, Thank you for your insights.
On Sun, 27 Sep 2020 at 15:12, Nicolas Goaziou <m...@nicolasgoaziou.fr> wrote: > > --8<---------------cut here---------------start------------->8--- > > guix build -m manifest.scm --with-input=emacs-minimal=emacs-next \ > > --with-input=emacs=emacs-next > > --8<---------------cut here---------------end--------------->8--- > > Possibly. And then Magit uses emacs-no-x as an input, so we may need to > also add --with-input=emacs-no-x=emacs-next to the command. [...] > Or maybe `package-with-emacs-next' could be more high-level, and handle > all of these cases. I don't know. I am not familiar with the Emacs build system. Do the packages need different flavors of the Emacs VM to be byte-compiled? For example, the package emacs-magit drags emacs-no-x because of emacs-libgit, why is emacs-minimal not enough here? Well, the emacs-build-system depends (implicitly) on emacs-minimal, only. And the initial patch `package-with-emacs-next' was changing this, only. However, the package emacs-libgit is cmake-build-system and the package emacs-no-x is an explicit dependency; which is another story. :-) Therefore, the `package-with-emacs-next' could replace the Emacs used by the build system (emacs-minimal -> emacs-next-minimal) and also traverse all the graph of dependencies and replace all the Emacs variants (emacs-{minimal,xwidgets,no-x,no-x-toolkit,wide-int}) in gnu/packages/emacs.scm by the package emacs-next. I am not sure it will work. Maybe the Emacs variants should also be rebuilt inheriting from emacs-next instead of emacs. WDYT? Does it make sense? All the best, simon