guix/etc/snippets/text-mode/guix-commit-message-add-package

# -*- mode: snippet -*-
# name: guix-commit-message-add-package
# key: add
# condition: git-commit-mode
# --
gnu: Add ${1:`(with-temp-buffer
                (magit-git-wash #'magit-diff-wash-diffs
                  "diff" "--staged")
                (goto-char (point-min))
                (when (re-search-forward "\\+(define-public \\(\\S-+\\)" nil 'noerror)
                  (match-string-no-properties 1)))`}.

* `(car (magit-staged-files))` ($1): New variable.