Support macOS Bash 3.2 in compile scripts

compile-app.sh

@@ -33,7 +33,7 @@ if [ "${#ALL_APPS[@]}" -eq 0 ]; then
 fi
 
 # --- select targets ---
-if [ "$#" -eq 0 ] || [ "${1,,}" = "all" ]; then
+if [ "$#" -eq 0 ] || [[ "${1:-}" == [Aa][Ll][Ll] ]]; then
     TARGETS=("${ALL_APPS[@]}")
 else
     TARGETS=()
@@ -56,7 +56,7 @@ mkdir -p "$OUT_DIR"
 # Give the container a pseudo-TTY when we are interactive, so build.sh's
 # single-line [k/3] progress refreshes in place (same trick as the firmware
 # build gives Ninja). Batch/redirected runs stay plain and line-oriented.
-TTY_ARGS=(); [[ -t 1 ]] && TTY_ARGS=(-t)
+TTY_ARG=""; [[ -t 1 ]] && TTY_ARG="-t"
 
 echo
 echo "🚀 Building overlay apps"
@@ -69,7 +69,7 @@ fail=0
 read_u32le() { od -An -tx1 -j"$2" -N4 "$1" | awk '{printf "0x%s%s%s%s",$4,$3,$2,$1}'; }
 
 for app in "${TARGETS[@]}"; do
-    if docker run --rm "${TTY_ARGS[@]}" -u "$(id -u):$(id -g)" \
+    if docker run --rm ${TTY_ARG:+"$TTY_ARG"} -u "$(id -u):$(id -g)" \
             -v "$PWD":/work -w "/work/$APPS_DIR/$app" \
             -e PATH="/opt/toolchain/bin:/usr/bin:/bin" -e APP_VMA="$APP_VMA" \
             "$IMAGE" bash ./build.sh; then

compile-firmware.sh

@@ -63,29 +63,32 @@ RESULT_RAM_SIZES=()
 
 run_preset_build() {
   local preset="$1"
-  local -a docker_tty_args=()
+  local docker_tty_arg=""
 
   # Give Ninja a pseudo-terminal for an interactive single-preset build. This
   # lets it refresh its [current/total] progress on one line. Batch/redirected
   # builds keep plain line-oriented output suitable for logs and CI.
   if (( INTERACTIVE && ! QUIET )); then
-    docker_tty_args=(-t)
+    docker_tty_arg="-t"
   fi
 
-  docker run --rm "${docker_tty_args[@]}" \
+  # The ${var:+...} and ${array[@]+...} forms avoid expanding an empty array,
+  # which Bash 3.2 treats as an unbound variable when nounset is enabled.
+  docker run --rm ${docker_tty_arg:+"$docker_tty_arg"} \
     -u "$(id -u):$(id -g)" \
     -v "$PWD":/src -w /src "$IMAGE" \
     bash -c 'which arm-none-eabi-gcc && arm-none-eabi-gcc --version &&
              cmake --fresh --preset "$1" "${@:2}" &&
              cmake --build --preset "$1" -j' \
-    bash "$preset" "${EXTRA_ARGS[@]}"
+    bash "$preset" ${EXTRA_ARGS[@]+"${EXTRA_ARGS[@]}"}
 }
 
 build_preset() {
   local preset="$1"
   local preset_slug log_file bin_file flash_size ram_size status
 
-  preset_slug="${preset,,}"
+  # macOS ships Bash 3.2, which does not support Bash 4's ${var,,} syntax.
+  preset_slug="$(printf '%s' "$preset" | tr '[:upper:]' '[:lower:]')"
   log_file="$(mktemp)"
   bin_file=""