fix(rime-install): end recursive call

rime-install

@@ -4,14 +4,10 @@ if [[ -z "${plum_repo}" ]]; then
     plum_repo='rime/plum'
 fi
 
-run_from_plum_dir=0
-
 if [[ -z "${plum_dir}" ]]; then
     # am I in a working copy already?
     plum_dir="$(dirname "$0")"
-    if [[ -f "${plum_dir}"/scripts/install-packages.sh ]]; then
-        run_from_plum_dir=1
-    else
+    if ! [[ -f "${plum_dir}"/scripts/install-packages.sh ]]; then
         # make a copy of plum in a subdirectory
         plum_dir='plum'
     fi
@@ -21,8 +17,8 @@ if ! [[ -e "${plum_dir}" ]]; then
     git clone --depth 1 "https://github.com/${plum_repo}.git" "${plum_dir}"
 fi
 
-if [[ "${run_from_plum_dir}" -eq 0 ]]; then
-    # run newer version of rime-install
+if ! [[ "$0" -ef "${plum_dir}"/rime-install ]]; then
+    # run the newer version of rime-install
     "${plum_dir}"/rime-install "$@"
     exit
 fi