fix: protect ${a[@]+"${a[@]}"} from IFS in Bash 5.2

In Bash 5.2, when IFS is an empty string, ${a[@]+"${a[@]}"} expands to
a single word containing all the elements of the array `a` being
joined. We need to ensure IFS being a normal value.

Author: akinomyoga

bash_completion

@@ -580,7 +580,8 @@ _comp__get_cword_at_cursor()
         ((index < 0)) && index=0
     fi
 
-    local "$2" "$3" "$4" && _comp_upvars -a${#words[@]} "$2" ${words+"${words[@]}"} \
+    local IFS=$' \t\n'
+    local "$2" "$3" "$4" && _comp_upvars -a${#words[@]} "$2" ${words[@]+"${words[@]}"} \
         -v "$3" "$cword" -v "$4" "${cur:0:index}"
 }
 

completions/ri

@@ -3,7 +3,7 @@
 
 _ri_get_methods()
 {
-    local regex
+    local regex IFS=$' \t\n'
 
     if [[ $ri_version == integrated ]]; then
         if [[ ! $separator ]]; then