1 files changed, 168 insertions, 0 deletions
diff --git a/rpath.sh b/rpath.sh
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index 0000000..ea84d21
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+++ b/rpath.sh
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+#!/usr/bin/env bash
+#
+# Copyright 2014 David Vazgenovich Shakaryan
+# Distributed under the terms of the MIT License.
+#
+# rpath
+# https://github.com/omp/rpath
+# Manage multiple Ruby installations with no black magic.
+#
+# In order to prevent environment pollution, the output of this script
+# is a list of commands which must be sourced. This can be achieved
+# through a simple shell function:
+#
+#     rpath() { source <(/path/to/rpath.sh "${@}"); }
+#
+# Two methods of version matching are supported. If the specified
+# argument consists of only numbers, it is matched against the list
+# number shown in `rpath ls`. Otherwise, a substring match is performed
+# against the directory name.
+
+: ${RUBIES_PATH:="${HOME}/.rubies"}
+
+_echo() {
+    echo "echo '${@//\'/\'\\\'\'}'"
+}
+
+_export_path() {
+    echo "export PATH='${PATH//\'/\'\\\'\'}'"
+    echo "hash -r"
+}
+
+_die() {
+    [[ -n "${@}" ]] && echo "echo '${@//\'/\'\\\'\'}' 1>&2"
+
+    echo "false"
+    exit 1
+}
+
+_populate_dirs() {
+    [[ -d "${RUBIES_PATH}" ]] \
+        || _die "Directory ${RUBIES_PATH} does not exist."
+
+    # Cannot handle paths containing a newline. Only an idiot would
+    # encounter this in practice.
+    readarray -t dirs < \
+        <(printf '%s\0' "${RUBIES_PATH}"/* | sort -zV | xargs -0n1)
+}
+
+_match() {
+    if [[ "${1}" =~ ^[0-9]+$ ]]; then
+        [[ "${2}" == "${1}" ]] && return
+    else
+        [[ "${3}" == *"${1}"* ]] && return
+    fi
+
+    return 1
+}
+
+_get() {
+    local dir dirs succeed=false
+
+    IFS=':' read -a dirs <<< "${PATH}"
+
+    for dir in "${dirs[@]}"; do
+        if [[ "${dir}" == "${RUBIES_PATH}/"* ]]; then
+            dir="${dir%/bin}"
+            echo "${dir##*/}"
+
+            succeed=true
+        fi
+    done
+
+    $succeed || return 1
+}
+
+_set() {
+    _clear
+    _echo "Adding ${1}/bin to PATH."
+
+    PATH="${1}/bin:${PATH}"
+}
+
+_clear() {
+    local dir dirs cdirs=() succeed=false
+
+    IFS=':' read -a dirs <<< "${PATH}"
+
+    for dir in "${dirs[@]}"; do
+        if [[ "${dir}" == "${RUBIES_PATH}/"* ]]; then
+            _echo "Removing ${dir} from PATH."
+
+            succeed=true
+        else
+            cdirs+=("${dir}")
+        fi
+    done
+
+    $succeed || return 1
+
+    PATH="$(IFS=':'; echo "${cdirs[*]}")"
+}
+
+rpath_ls() {
+    _populate_dirs
+
+    counter=0
+    current=$(_get | head -n 1)
+
+    for dir in "${dirs[@]}"; do
+        str="[$((++counter))] ${dir##*/}"
+
+        [[ "${dir##*/}" == "${current}" ]] && str+=" *"
+
+        _echo "${str}"
+    done
+}
+
+rpath_get() {
+    current="$(_get)" && _echo "${current}"
+}
+
+rpath_set() {
+    [[ -z "${1}" ]] && _die 'rpath set requires an argument.'
+
+    _populate_dirs
+
+    counter=0
+
+    for dir in "${dirs[@]}"; do
+        if _match "${1}" "$((++counter))" "${dir##*/}"; then
+            _set "${dir}"
+            _export_path
+
+            return
+        fi
+    done
+
+    _die 'No matching ruby found.'
+}
+
+rpath_clear() {
+    _clear || _die 'No rubies found in PATH.'
+    _export_path
+}
+
+rpath_help() {
+    _echo 'Usage: rpath <command> [args]'
+    _echo
+    _echo 'Available options:'
+    _echo '  ls     List all available rubies.'
+    _echo '  get    Display currently selected ruby.'
+    _echo '  set    Select specified ruby.'
+    _echo '  clear  Clear path of any rpath rubies.'
+    _echo '  help   Display this help information.'
+}
+
+case "${1}" in
+    'ls')
+        rpath_ls ;;
+    'get')
+        rpath_get ;;
+    'set')
+        rpath_set "${2}" ;;
+    'clear')
+        rpath_clear ;;
+    *)
+        rpath_help ;;
+esac