Prevent removing the currently active version of Node.js/io.js

bin/n

@@ -4,7 +4,7 @@
 # Setup.
 #
 
-VERSION="1.4.0"
+VERSION="1.4.2"
 UP=$'\033[A'
 DOWN=$'\033[B'
 N_PREFIX=${N_PREFIX-/usr/local}
@@ -483,8 +483,11 @@ set_quiet() {
 
 remove_versions() {
   test -z $1 && abort "version(s) required"
+  check_current_version
   while test $# -ne 0; do
-    rm -rf ${VERSIONS_DIR[$DEFAULT]}/${1#v}
+    local version=${1#v}
+    [ "${BINS[$DEFAULT]}/$version" == "$active" ] && abort "cannot remove currently active version ($active)"
+    rm -rf ${VERSIONS_DIR[$DEFAULT]}/$version
     shift
   done
 }

package.json

@@ -1,7 +1,7 @@
 {
   "name": "n",
   "description": "node version manager",
-  "version": "1.4.1",
+  "version": "1.4.2",
   "author": "TJ Holowaychuk <[email protected]>",
   "homepage": "https://github.com/tj/n",
   "bugs": "https://github.com/tj/n/issues",