fix(_variables): protect from failglob

Author: akinomyoga

bash_completion

@@ -679,9 +679,12 @@ _variables()
         return 0
     elif [[ $cur =~ ^(\$\{[#!]?)([A-Za-z0-9_]*)\[([^]]*)$ ]]; then
         # Complete ${array[i with ${array[idx]}
-        local IFS=$'\n'
+        local reset=$(shopt -po noglob) IFS=$'\n'
+        set -o noglob
         COMPREPLY+=($(compgen -W '$(printf %s\\n "${!'${BASH_REMATCH[2]}'[@]}")' \
             -P "${BASH_REMATCH[1]}${BASH_REMATCH[2]}[" -S ']}' -- "${BASH_REMATCH[3]}"))
+        IFS=$' \t\n'
+        $reset
         # Complete ${arr[@ and ${arr[*
         if [[ ${BASH_REMATCH[3]} == [@*] ]]; then
             COMPREPLY+=("${BASH_REMATCH[1]}${BASH_REMATCH[2]}[${BASH_REMATCH[3]}]}")