diff --git a/vimfiles/tools/shell/bash/update-tags.sh b/vimfiles/tools/shell/bash/update-tags.sh
index 56c87854..fca5b2de 100644
--- a/vimfiles/tools/shell/bash/update-tags.sh
+++ b/vimfiles/tools/shell/bash/update-tags.sh
@@ -3,12 +3,12 @@
 # create tags
 echo "Creating Tags..."
 
-if [ ${CUSTOM} = true ]; then
+if [[ ${CUSTOM} = true ]]; then
     echo "  |- move custom ctags to ${TARGET}"
     cp "${SOURCE}" "${TARGET}"
 else
     # choose ctags path first
-    if [ -f "${DEST}/files" ]; then
+    if [[ -f "${DEST}/files" ]]; then
         FILES="-L ${DEST}/files"
     else
         FILES="-R ."
@@ -19,7 +19,7 @@ else
     ${CTAGS_CMD} -o "${TMP}" ${OPTIONS} "${FILES}"
 
     # replace old file
-    if [ -f "${TMP}" ]; then
+    if [[ -f "${TMP}" ]]; then
         echo "  |- move ${TMP} to ${TARGET}"
         mv -f "${TMP}" "${TARGET}"
     fi