fix(set-u): initialize locals and guard network.sh calls in auto_detect_fqdn and detect_ipv6_prefix

network_find_wan/network_find_wan6 internally unset their dest variable before
populating it via eval. Under set -u, the subsequent empty check crashes with
"parameter not set". Fix: initialize all locals to "" and wrap network.sh
calls with set +u / set -u using ${VAR:-} default expansion on the check.

test(integration): add Suite 12 — auto-detect server settings (option 4), 95 tests passing

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

Author: beadon

openvpn_server_management.sh

@@ -665,26 +665,29 @@ check_ipv6_subnet_conflict() {
 
 # Function to detect IPv6 prefix delegation from WAN
 detect_ipv6_prefix() {
-    local WAN6_IF
-    local wan6_addrs
-    local prefix_delegation
-    local prefix_size
-    local lan_ipv6
-    local lan_prefix
+    local WAN6_IF=""
+    local wan6_addrs=""
+    local prefix_delegation=""
+    local prefix_size=""
+    local lan_ipv6=""
+    local lan_prefix=""
 
     echo "Detecting IPv6 configuration from WAN interface..."
     echo ""
 
-    # Get WAN interface name
+    # Get WAN interface name — network.sh may unset the dest var if no route found,
+    # so keep set +u active until after the empty check.
     . /lib/functions/network.sh
     network_flush_cache
+    set +u
     network_find_wan6 WAN6_IF
-
-    if [ -z "$WAN6_IF" ]; then
+    if [ -z "${WAN6_IF:-}" ]; then
+        set -u
         echo "  No WAN IPv6 interface found"
         echo "  IPv6 may not be configured on this router"
         return 1
     fi
+    set -u
 
     echo "  WAN IPv6 interface: $WAN6_IF"
 
@@ -759,17 +762,17 @@ detect_ipv6_prefix() {
 
 # Auto-Detect DDNS configured name, Fetch server address configured elsewhere
 auto_detect_fqdn() {
-    local DETECTED_PORT
-    local DETECTED_PROTO
-    local DETECTED_POOL
-    local DETECTED_IPV6_POOL
-    local rule_index
-    local rule_name
-    local rule_dest_port
-    local rule_proto
-    local NET_FQDN
-    local NET_IF
-    local NET_ADDR
+    local DETECTED_PORT=""
+    local DETECTED_PROTO=""
+    local DETECTED_POOL=""
+    local DETECTED_IPV6_POOL=""
+    local rule_index=""
+    local rule_name=""
+    local rule_dest_port=""
+    local rule_proto=""
+    local NET_FQDN=""
+    local NET_IF=""
+    local NET_ADDR=""
 
     echo ""
     echo "Script default settings (if no config found):"
@@ -877,12 +880,14 @@ auto_detect_fqdn() {
     # Update DNS based on detected pool
     OVPN_DNS="${OVPN_POOL%.* *}.1"
 
-    # Detect server FQDN/IP
+    # Detect server FQDN/IP — network.sh may unset dest vars; keep set +u active
     NET_FQDN="$(uci -q get ddns.@service[0].lookup_host)"
     . /lib/functions/network.sh
     network_flush_cache
+    set +u
     network_find_wan NET_IF
-    network_get_ipaddr NET_ADDR "${NET_IF}"
+    network_get_ipaddr NET_ADDR "${NET_IF:-}"
+    set -u
     if [ -n "${NET_FQDN}" ]
     then
         OVPN_SERV="${NET_FQDN}"

tests/integration_test.sh

@@ -607,6 +607,27 @@ check wait_for "testvpn" 5
 expect_send "Press Enter" "" 5
 check wait_for "Select an option:" 5
 
+# ── Suite 12: Auto-detect Server Settings ────────────────────────────────────
+# option 4 is read-only: detects port/proto from server.conf and firewall rules,
+# WAN IP from UCI, and prints "Final Settings". No user prompts — returns
+# directly to the main menu after output.
+
+printf "\n--- [%s] Suite 12: Auto-detect Server Settings (option 4) ---\n" "$(ts)"
+
+it "option 4 detects settings from server.conf and prints final summary"
+select_option "4"
+wait_for "Detecting configuration" 5
+# server.conf exists from Suite 2 — port and protocol should be detected
+wait_for "Detected port" 10
+wait_for "Final Settings" 10
+# No Press Enter gate — returns directly to menu; allow time for network detection
+check wait_for "Select an option:" 20
+
+it "option 4 reports a VPN server address"
+select_option "4"
+wait_for "Detected WAN IP\|Detected DDNS" 20
+check wait_for "Select an option:" 20
+
 # ── Done ──────────────────────────────────────────────────────────────────────
 
 quit_script