pkgs/fupdate-sys: Avoid unset variable errors

1 files changed, 3 insertions, 7 deletions

diff --git a/pkgs/by-name/fu/fupdate-sys/fupdate-sys.sh b/pkgs/by-name/fu/fupdate-sys/fupdate-sys.sh
index 435c45a8..28e09f3d 100755
--- a/pkgs/by-name/fu/fupdate-sys/fupdate-sys.sh
+++ b/pkgs/by-name/fu/fupdate-sys/fupdate-sys.sh
@@ -107,7 +107,7 @@ while [ "$#" -gt 0 ]; do
         help 0
         ;;
     "--branch" | "-b")
-        if [ -n "$2" ]; then
+        if [ "${2-unset}" != "unset" ]; then
             BRANCH="$2"
         else
             error "$1 requires an argument"
@@ -116,7 +116,7 @@ while [ "$#" -gt 0 ]; do
         shift 2
         ;;
     "--mode" | "-m")
-        if [ -n "$2" ]; then
+        if [ "${2-unset}" != "unset" ]; then
             MODE="$2"
         else
             error "$1 requires an argument"
@@ -150,11 +150,7 @@ trap cleanup EXIT
 git remote show origin | grep 'HEAD' | cut -d':' -f2 | sed -e 's/^ *//g' -e 's/ *$//g' >"$default_branch" &
 
 msg2 "Updating system..."
-if [ -n "$MODE" ]; then
-    nixos-rebuild "$MODE"
-else
-    nixos-rebuild switch
-fi
+nixos-rebuild "${MODE-switch}"
 
 git switch "$(cat "$default_branch")" >/dev/null 2>&1 && msg2 "Switched to branch '$(cat "$default_branch")'"
 msg "Finished Update!"