refactor: reduce trivial _comp_compgen -- -W '"${COMPREPLY[@]}"'

There are also more non-trivial cases where COMPREPLY is first
constructed and then filtered by `_comp_compgen -- -W
'"${COMPREPLY[@]}"'`, but they would conflict with forthcoming other
PRs for _comp_compgen rewrite.  We will address them after finishing
the _comp_compgen-related PRs.

Co-authored-by: Ville Skyttä <ville.skytta@iki.fi>

Author: akinomyoga

completions/ifup

@@ -33,8 +33,6 @@ _comp_cmd_ifupdown()
 
     if ((args == 1)); then
         _configured_interfaces
-        ((${#COMPREPLY[@]})) &&
-            _comp_compgen -- -W '"${COMPREPLY[@]}"'
     fi
 } &&
     complete -F _comp_cmd_ifupdown ifup ifdown ifquery ifstatus

completions/ip

@@ -334,8 +334,7 @@ _comp_cmd_ip()
                     if [[ $cword -eq $subcword+1 || $prev == dev ]]; then
                         _available_interfaces
                         if [[ $prev != dev ]]; then
-                            COMPREPLY+=(dev)
-                            _comp_compgen -- -W '"${COMPREPLY[@]}"'
+                            _comp_compgen -a -W dev
                         fi
                     fi
                     ;;

completions/smartctl

@@ -4,14 +4,10 @@ _comp_cmd_smartctl__device()
 {
     case $cur in
         areca* | 3ware* | megaraid* | cciss*)
-            # shellcheck disable=SC2054
-            COMPREPLY=(${cur%%,*},{0..31})
-            _comp_compgen -- -W '"${COMPREPLY[@]}"'
+            _comp_compgen -- -W '${cur%%,*},{0..31}'
             ;;
         hpt*)
-            # shellcheck disable=SC2054
-            COMPREPLY=(hpt,{1..4}/{1..8} hpt,{1..4}/{1..8}/{1..5})
-            _comp_compgen -- -W '"${COMPREPLY[@]}"'
+            _comp_compgen -- -W 'hpt,{1..4}/{1..8} hpt,{1..4}/{1..8}/{1..5}'
             ;;
         *)
             COMPREPLY=($(compgen -W "ata scsi sat usbcypress usbjmicron

completions/tune2fs

@@ -15,8 +15,7 @@ _comp_cmd_tune2fs()
             ;;
         -*g)
             _gids
-            ((${#COMPREPLY[@]})) &&
-                _comp_compgen -- -g -W '"${COMPREPLY[@]}"'
+            _comp_compgen -a -- -g
             return
             ;;
         -*M)
@@ -40,8 +39,7 @@ _comp_cmd_tune2fs()
             ;;
         -*u)
             _uids
-            ((${#COMPREPLY[@]})) &&
-                _comp_compgen -- -u -W '"${COMPREPLY[@]}"'
+            _comp_compgen -a -- -u
             return
             ;;
         -*U)

completions/useradd

@@ -30,9 +30,7 @@ _comp_cmd_useradd()
             ;;
         --gid | -${noargopts}g)
             _gids
-            _comp_compgen -aR -- -g
-            ((${#COMPREPLY[@]})) &&
-                _comp_compgen -- -W '"${COMPREPLY[@]}"'
+            _comp_compgen -a -- -g
             return
             ;;
         --groups | -${noargopts}G)

completions/usermod

@@ -26,9 +26,7 @@ _comp_cmd_usermod()
             ;;
         --gid | -${noargopts}g)
             _gids
-            _comp_compgen -aR -- -g
-            ((${#COMPREPLY[@]})) &&
-                _comp_compgen -- -W '"${COMPREPLY[@]}"'
+            _comp_compgen -a -- -g
             return
             ;;
         --groups | -${noargopts}G)