app-doc/gimp-help: Add IUSE="nls" and fix LINGUAS logic

Follow standard gettext behavior:
- USE="-nls": build only English documentation (and ignore LINGUAS)
- USE="nls" and unset LINGUAS: build all available languages
- USE="nls" and empty LINGUAS: build only English
- USE="nls" and nonempty LINGUAS: build listed languages if supported

See also the following mailing list posting for an explanation:
https://archives.gentoo.org/gentoo-dev/message/38914ce4a7a228d2d29fb623346fba10#L29

Bug: https://bugs.gentoo.org/891709
Signed-off-by: Ulrich Müller <ulm@gentoo.org>

2 files changed, 75 insertions, 65 deletions

diff --git a/app-doc/gimp-help/gimp-help-2.10.34-r1.ebuild b/app-doc/gimp-help/gimp-help-2.10.34-r1.ebuild
deleted file mode 100644
index 2837213514fe..000000000000
--- a/app-doc/gimp-help/gimp-help-2.10.34-r1.ebuild
+++ /dev/null
@@ -1,65 +0,0 @@
-# Copyright 1999-2023 Gentoo Authors
-# Distributed under the terms of the GNU General Public License v2
-
-EAPI=8
-
-PYTHON_COMPAT=( python3_{9..11} )
-inherit python-any-r1
-
-DESCRIPTION="GNU Image Manipulation Program help files"
-HOMEPAGE="https://docs.gimp.org/"
-SRC_URI="mirror://gimp/help/${P}.tar.bz2"
-
-LICENSE="FDL-1.2"
-SLOT="2"
-KEYWORDS="~alpha ~amd64 ~hppa ~ia64 ~ppc ~ppc64 ~riscv ~sparc ~x86"
-IUSE=""
-
-BDEPEND="
-	${PYTHON_DEPS}
-	$(python_gen_any_dep 'dev-libs/libxml2[python,${PYTHON_USEDEP}]')
-	app-text/docbook-xml-dtd
-	dev-lang/perl
-	dev-libs/libxslt
-	gnome-base/librsvg
-	sys-devel/gettext
-"
-
-DOCS=( AUTHORS COPYING NEWS README )
-
-python_check_deps() {
-	python_has_version "dev-libs/libxml2[python,${PYTHON_USEDEP}]"
-}
-
-pkg_setup() {
-	# See bug: 891709
-	if [[ -z "${LINGUAS}" ]] ; then
-		export LINGUAS="en"
-
-		ewarn "The 'LINGUAS' environment variable isn't setup in '/etc/portage/make.conf',"
-		ewarn "therefore only the generic ('en') documentation will be built."
-		ewarn "To build ${PN} for other languages please setup 'LINGUAS' variable"
-		ewarn "or assign it to 'L10N' variable if available, i.e. LINGUAS=\"\${L10N}\""
-		ewarn "The following languages are supported for ${PN}:"
-		ewarn "'ca cs da de el en en_GB es fa fi fr hr hu it ja ko lt nl nn pt pt_BR ro ru sl sv uk zh_CN'"
-		ewarn "For more details please read:"
-		ewarn "https://wiki.gentoo.org/wiki/Localization/Guide#LINGUAS"
-	fi
-}
-
-src_configure() {
-	econf --without-gimp
-}
-
-src_compile() {
-	# See bug: 833566
-	python_export_utf8_locale
-	# Affected with bugs: 677198, 876205. Set "emake -j1"
-	emake -j1
-}
-
-src_install() {
-	# See bug: 905693
-	emake -j1 DESTDIR="${D}" install
-	einstalldocs
-}
diff --git a/app-doc/gimp-help/gimp-help-2.10.34-r2.ebuild b/app-doc/gimp-help/gimp-help-2.10.34-r2.ebuild
new file mode 100644
index 000000000000..9bb1d39037c8
--- /dev/null
+++ b/app-doc/gimp-help/gimp-help-2.10.34-r2.ebuild
@@ -0,0 +1,75 @@
+# Copyright 1999-2023 Gentoo Authors
+# Distributed under the terms of the GNU General Public License v2
+
+EAPI=8
+
+PYTHON_COMPAT=( python3_{9..11} )
+inherit python-any-r1
+
+DESCRIPTION="GNU Image Manipulation Program help files"
+HOMEPAGE="https://docs.gimp.org/"
+SRC_URI="mirror://gimp/help/${P}.tar.bz2"
+
+LICENSE="FDL-1.2"
+SLOT="2"
+KEYWORDS="~alpha ~amd64 ~hppa ~ia64 ~ppc ~ppc64 ~riscv ~sparc ~x86"
+IUSE="nls"
+
+BDEPEND="
+	${PYTHON_DEPS}
+	$(python_gen_any_dep 'dev-libs/libxml2[python,${PYTHON_USEDEP}]')
+	app-text/docbook-xml-dtd
+	dev-lang/perl
+	dev-libs/libxslt
+	gnome-base/librsvg
+	sys-devel/gettext
+"
+
+DOCS=( AUTHORS COPYING NEWS README )
+
+python_check_deps() {
+	python_has_version "dev-libs/libxml2[python,${PYTHON_USEDEP}]"
+}
+
+pkg_setup() {
+	# The upstream build system isn't pure gettext and doesn't distinguish
+	# between empty and unset LINGUAS. Default to English only if either
+	# nls is unset or if LINGUAS exists but is empty. #891709
+	if ! use nls || [[ -v LINGUAS && -z ${LINGUAS} ]]; then
+		export LINGUAS="en"
+	elif [[ ! -v LINGUAS ]]; then
+		local line
+		while read line; do ewarn "${line}"; done <<-EOF
+			The "LINGUAS" variable is unset in your configuration,
+			but the "nls" USE flag is set. Therefore, documentation for
+			*all* languages will be built, which may take quite some time.
+			If you want to install documentation for a defined list
+			of languages, please assign "LINGUAS" accordingly.
+			The following languages are supported for ${CATEGORY}/${PN}:
+			"ca cs da de el en en_GB es fa fi fr hr hu it ja ko lt nl nn
+			pt pt_BR ro ru sl sv uk zh_CN"
+			If you want to install only the English documentation, it is
+			recommended to unset the "nls" USE flag for ${CATEGORY}/${PN}.
+
+			For more details please read:
+			https://wiki.gentoo.org/wiki/Localization/Guide#LINGUAS
+		EOF
+	fi
+}
+
+src_configure() {
+	econf --without-gimp
+}
+
+src_compile() {
+	# See bug: 833566
+	python_export_utf8_locale
+	# Affected with bugs: 677198, 876205. Set "emake -j1"
+	emake -j1
+}
+
+src_install() {
+	# See bug: 905693
+	emake -j1 DESTDIR="${D}" install
+	einstalldocs
+}