Initial version that seems to work more or less.

Intended for some testing, not yet for release.

1 files changed, 205 insertions, 0 deletions

diff --git a/eselect-gem/gem.eselect b/eselect-gem/gem.eselect
new file mode 100644
index 0000000..40bf7f5
--- /dev/null
+++ b/eselect-gem/gem.eselect
@@ -0,0 +1,205 @@
+# Copyright 1999-2007 Gentoo Foundation
+# Distributed under the terms of the GNU General Public License v2
+# $Id: vi.eselect 261 2006-03-30 21:11:55Z kugelfang $
+
+DESCRIPTION="Manage binaries provided by slotted gems."
+MAINTAINER="graaff@gentoo.org"
+
+# Manage binaries installed by gems. Since gems install their binaries
+# in a standard manner we can handle them with a single eselect
+# module.
+
+# Usage: eselect gems <gemname> <version> <binaries>
+
+# This creates symlinks in /usr/bin to the versioned binaries in the
+# gem bin directory.
+
+GEM_DIR="$(gem env gemdir)"
+GEM_BIN_DIR="$GEM_DIR/bin"
+
+# get_executables(gemname)
+find_executables() {
+	# Parse the specifications file to get the list of executables as
+	# specified by the gem. Pick the last version.
+	echo $(grep -h s.executables "$GEM_DIR/specifications/${1}"-*.gemspec | tail -n 1 | cut --delimiter="=" --fields=2 | tr -d "[]\"/,")
+}
+
+# find a list of versions for this gem
+find_targets() {
+	for f in "${GEM_DIR}/gems/${1}-"* ; do
+		if [[ -d ${f} ]] ; then
+			echo $(basename ${f} )
+		fi
+	done
+}
+
+# Try to remove the current symlinks for all the current executables
+remove_symlinks() {
+	local executables=( $( find_executables ${1} ) )
+
+	for (( i = 0 ; i < ${#executables[@]} ; i = i + 1 )) ; do
+				target="${ROOT}/usr/bin/${executables[${i}]}"
+		rm ${target} &>/dev/null
+	done
+}
+
+# set the symlinks for all the executables
+set_symlinks() {
+	local gem=${1}
+	local target=${2}
+
+	if is_number "${target}" && [[ ${target} -ge 1 ]] ; then
+		targets=( $(find_targets ${1}) )
+		target=${targets[$(( ${target} - 1 ))]}
+		target=$(echo $target | cut --delimiter="-" --fields=2)
+	fi
+
+	local executables=( $( find_executables ${1} ) )
+
+	for (( i = 0 ; i < ${#executables[@]} ; i = i + 1 )) ; do
+				executable="${ROOT}/usr/bin/${executables[${i}]}"
+
+				if [[ -f "${executable}-${target}" ]] ; then
+					ln -s "${executable}-${target}" "${executable}" || \
+						die "Couldn't set ${target} symlink"
+				else
+					die -q  "Target \"${target}\" doesn't appear to be valid!"
+				fi
+	done
+}
+
+set_symlink_default() {
+	set_symlink 1
+}
+
+set_symlink_by_slot() {
+	slot=${1}
+	local target=$(ls  ${RAILS}-${slot}* 2>/dev/null)
+	if [[ -n ${target}  ]]; then
+		remove_symlinks
+		ln -s ${target} ${RAILS}
+	else
+		die -q "No providers available for slot ${slot}"
+	fi
+}
+
+### show action ###
+
+describe_show() {
+	echo "Show the currently selected version for the specific gem"
+}
+
+do_show() {
+	if [[ "x${1}" == "x"  ]]; then
+		die -q "Usage error: a gem name is required."
+	fi
+
+	local executables=( $( find_executables ${1} ) )
+	local executable="${ROOT}/usr/bin/${executables[0]}"
+
+	write_list_start "Current ${1} version:"
+	if [[ -L "${executable}" ]] ; then
+		write_kv_list_entry "$(basename $(canonicalise ${executable} ) )" ""
+	elif [[ -e "${executable}" ]] ; then
+		write_kv_list_entry "(not a symlink: ${executable})" ""
+	else
+		write_kv_list_entry "(unset)" ""
+	fi
+}
+
+### list action ###
+
+describe_list() {
+	echo "List available versions for the specific gem"
+}
+
+do_list() {
+	if [[ "x${1}" == "x"  ]]; then
+		die -q "Usage error: a gem name is required."
+	fi
+
+	local executables=( $( find_executables ${1} ) )
+	local executable="${ROOT}/usr/bin/${executables[0]}"
+
+	# Find all the targets. Basically this means all the versions of
+	# the gem that are installed.
+	local i targets
+	targets=( $(find_targets ${1}) )
+	if [[ -n ${targets[@]} ]] ; then
+		for (( i = 0 ; i < ${#targets[@]} ; i = i + 1 )) ; do
+					[[ ${targets[${i}]} = \
+						$(basename $(canonicalise ${executable}) ) ]] &&
+					targets[${i}]="${targets[${i}]} $(highlight '*')"
+		done
+		write_list_start "Available ${1} versions:"
+		write_numbered_list "${targets[@]}"
+	else
+		write_kv_list_entry "(none found)" ""
+	fi
+}
+
+### set action ###
+
+describe_set() {
+	echo "Set a new version for the specific gem"
+}
+
+describe_set_options() {
+	echo "target : Target name or number (from 'list' action)"
+}
+
+describe_set_parameters() {
+	echo "<target>"
+}
+
+do_set() {
+	if [[ $# != 2  ]]; then
+		die -q "Usage error: a gem name and a new setting are required."
+	fi
+
+	local gem=${1}
+	local version=${2}
+
+	local executables=( $( find_executables ${gem} ) )
+	local executable="${ROOT}/usr/bin/${executables[0]}"
+
+	if [[ -z ${version} ]] ; then
+		die -q "You didn't give me a version name"
+	elif [[ -L "${executable}" ]] ; then
+		if ! remove_symlinks ${gem} ; then
+			die -q "Can't remove existing ${executable} binary"
+		elif ! set_symlinks ${gem} "${version}" ; then
+			die -q "Can't set new ${executable} binary"
+		fi
+	elif [[ -e "${executable}" ]] ; then
+		write_warning_msg "Can't set a new ${executable} provider. There's a file in the way at ${executable}. You can try removing it manually, and then re-running this command."
+	else
+		set_symlinks ${gem} ${version} || die -q "Wasn't able to set a new provider"
+	fi
+}
+
+### update action ###
+
+describe_update() {
+	echo "Updates the symlink(s) to the latest version available"
+}
+
+do_update() {
+	# Only set a symlink if there are any version of rails present
+	local target=1
+	local targets=( $(find_targets ) )
+
+	if [[ -z ${targets[@]} ]] ; then
+		remove_symlinks
+	fi
+
+	target=${targets[$(( ${target} - 1 ))]}
+	if [[ -f "${ROOT}/usr/bin/${target}" ]] ; then
+		set_symlink_default
+	fi
+
+	do_show
+}
+
+# vim: set ft=eselect :
+