* emacs/guix-main.scm (process-package-actions): Set grafting according
to 'dry-run?'.
* guix/scripts.scm (build-package): Disable grafts when 'dry-run?' is #t.
Co-authored-by: Ludovic Courtès <ludo@gnu.org>
Suggested by Ludovic Courtès <ludo@gnu.org>.
* guix/scripts.scm (build-package-source): New procedure.
* emacs/guix-devel.el (guix-devel-build-package-source): New command.
(guix-devel-keys-map): Add key binding for it.
* doc/emacs.texi (Emacs Development): Document it.