Re: [gentoo-dev] [RFC] new vala.eclass

[Alexandre Rostovtsev <tetromino@gentoo.org>]

On Sun, 2012-09-09 at 22:09 -0400, Alexandre Rostovtsev wrote:
> Revised proposal with suggestions from Nirbheek. VALA_API_VERSION has
> been split into max and min to make it easier for packages to depend on
> a range of vala slots.
> 
> # Copyright 1999-2012 Gentoo Foundation
> # Distributed under the terms of the GNU General Public License v2
> # $Header: $
> 
> # @ECLASS: vala.eclass
> # @MAINTAINER:
> # gnome@gentoo.org
> # @AUTHOR:
> # Alexandre Rostovtsev <tetromino@gentoo.org>
> # @BLURB: Sets up the environment for using a specific version of vala.
> # @DESCRIPTION:
> # This eclass sets up commonly used environment variables for using a specific
> # version of dev-lang/vala to configure and build a package. It is needed for
> # packages whose build systems assume the existence of certain unversioned vala
> # executables, pkgconfig files, etc., which Gentoo does not provide.
> #
> # This eclass provides one phase function: src_prepare.
> 
> inherit multilib
> 
> case "${EAPI:-0}" in
> 	0)	die "EAPI=0 is not supported" ;;
> 	1)	;;
> 	*)	EXPORT_FUNCTIONS src_prepare ;;
> esac
> 
> # @ECLASS-VARIABLE: VALA_MIN_API_VERSION
> # @DEFAULT_UNSET
> # @DESCRIPTION:
> # Minimum vala API version (e.g. 0.16).
> VALA_MIN_API_VERSION=${VALA_MIN_API_VERSION:-0.10}
> 
> # @ECLASS-VARIABLE: VALA_MAX_API_VERSION
> # @DEFAULT_UNSET
> # @DESCRIPTION:
> # Maximum vala API version (e.g. 0.18).
> VALA_MAX_API_VERSION=${VALA_MAX_API_VERSION:-0.18}
> 
> # @ECLASS-VARIABLE: VALA_USE_DEPEND
> # @DEFAULT_UNSET
> # @DESCRIPTION:
> # USE dependencies that vala must be built with (e.g. vapigen).
> 
> # @FUNCTION: vala_api_versions
> # @DESCRIPTION:
> # Outputs a list of vala API versions from VALA_MAX_API_VERSION down to
> # VALA_MIN_API_VERSION.
> vala_api_versions() {
> 	eval "echo 0.{${VALA_MAX_API_VERSION#0.}..${VALA_MIN_API_VERSION#0.}..2}"
> }
> 
> # @FUNCTION: vala_depend
> # @DESCRIPTION:
> # Outputs a ||-dependency string on vala from VALA_MAX_API_VERSION down to
> # VALA_MIN_API_VERSION
> vala_depend() {
> 	local u v versions=$(vala_api_versions)
> 	[[ ${VALA_USE_DEPEND} ]] && u="[${VALA_USE_DEPEND}]"
> 
> 	echo -n "|| ("
> 	for v in ${versions}; do
> 		echo -n " dev-lang/vala:${v}${u}"
> 	done
> 	echo " )"
> }
> 
> # @FUNCTION: vala_best_api_version
> # @DESCRIPTION:
> # Returns the highest installed vala API version satisfying
> # VALA_MAX_API_VERSION, VALA_MIN_API_VERSION, and VALA_USE_DEPEND.
> vala_best_api_version() {
> 	local u v
> 	[[ ${VALA_USE_DEPEND} ]] && u="[${VALA_USE_DEPEND}]"
> 	for v in $(vala_api_versions); do
> 		has_version "dev-lang/vala:${v}${u}" && echo "${v}" && return
> 	done
> }
> 
> # @FUNCTION: vala_src_prepare
> # @USAGE: [--vala-api-version api_version]
> # @DESCRIPTION:
> # Sets up the environment variables and pkgconfig files for the
> # specified API version, or, if no version is specified, for the
> # highest installed vala API version satisfying
> # VALA_MIN_API_VERSION, VALA_MIN_API_VERSION, and VALA_USE_DEPEND.
> vala_src_prepare() {
> 	local p d valafoo version
> 
> 	if [[ $1 = "--vala-api-version" ]]; then
> 		version=$2
> 		[[ ${version} ]] || die "'--vala-api-version' option requires API version parameter."
> 	else
> 		version=$(vala_best_api_version)
> 		[[ ${version} ]] || die "No installed vala in $(vala_depend)"
> 	fi
> 
> 	export VALAC=$(type -P valac-${version})
> 
> 	valafoo=$(type -P vala-gen-introspect-${VALA_API_VERSION})
> 	[[ ${valafoo} ]] && export VALA_GEN_INTROSPECT=$(type -P vala-gen-introspect-${version})
> 
> 	valafoo=$(type -P vapigen-${VALA_API_VERSION})
> 	[[ ${valafoo} ]] && export VAPIGEN="${valafoo}"
> 
> 	valafoo="${EPREFIX}/usr/share/vala/Makefile.vapigen"
> 	[[ -e ${valafoo} ]] && export VAPIGEN_MAKEFILE="${valafoo}"
> 
> 	export VAPIGEN_VAPIDIR="${EPREFIX}/usr/share/vala/vapi"
> 
> 	mkdir -p "${T}/pkgconfig" || die "mkdir failed"
> 	for p in libvala vapigen; do
> 		for d in "${EPREFIX}/usr/$(get_libdir)/pkgconfig" "${EPREFIX}/usr/share/pkgconfig"; do
> 			if [[ -e ${d}/${p}-${VALA_API_VERSION}.pc ]]; then
> 				ln -s "${d}/${p}-${VALA_API_VERSION}.pc" "${T}/pkgconfig/${p}.pc" || die "ln failed"
> 				break
> 			fi
> 		done
> 	done
> 	: ${PKG_CONFIG_PATH:="${EPREFIX}/usr/$(get_libdir)/pkgconfig:${EPREFIX}/usr/share/pkgconfig"}
> 	export PKG_CONFIG_PATH="${T}/pkgconfig:${PKG_CONFIG_PATH}"
> }

Now in portage.