This is a script to update translation source strings from mods' lua source code. The script is for Minetest mods that supports intllib and had strings needing translation passed via intllib's functions declared correctly. The script was taken from homedecor_modpack and tweaked it so it is usable in common mods' locale folder.

updatepo.sh

#! /bin/bash

# To create a new translation:
#   msginit --locale=ll_CC -o locale/ll_CC.po -i locale/template.pot

cd "$(dirname "${BASH_SOURCE[0]}")/..";

# Extract translatable strings.
xgettext --from-code=UTF-8 \
		--language=Lua \
		--sort-by-file \
		--keyword=S \
		--keyword=NS:1,2 \
		--keyword=N_ \
		--add-comments='Translators:' \
		--add-location=file \
		-o locale/template.pot \
		$(find . -name '*.lua')

# Update translations.
find locale -name '*.po' | while read -r file; do
	echo $file
	msgmerge --update $file locale/template.pot;
done

The script was taken from minetest-mods/homedecor_modpack/homedecor_i18n/tools/updatepo.sh and tweaked it so it is usable in common mods' locale folder. See homedecor_modpack's license for reusing this code.