. "$(git --exec-path)/git-sh-i18n"
This is not a command the end user would want to run. Ever. This documentation is meant for people who are studying the Porcelain-ish scripts and/or are writing new ones.
The 'git sh-i18n scriptlet is designed to be sourced (using .) by Git's porcelain programs implemented in shell script. It provides wrappers for the GNU gettext and eval_gettext functions accessible through the gettext.sh script, and provides pass-through fallbacks on systems without GNU gettext.
gettext
eval_gettext
Part of the git(1) suite