Quote all variables in numeric comparisons for safety

testing/validate-plesk.sh

@@ -335,7 +335,7 @@ if command -v mysql &> /dev/null; then
         test_info "Databases without underscores: $NO_UNDERSCORES"
 
         # Check if databases follow username_ pattern or no prefix
-        if [ $NO_UNDERSCORES -gt 0 ]; then
+        if [ "$NO_UNDERSCORES" -gt 0 ]; then
             test_info "Found databases without underscores (suggests NO PREFIX pattern)"
             test_info "Sample databases without prefix:"
             echo "$DB_LIST" | grep -v "_" | grep -v "test" | head -5 >> "$RESULTS_FILE"
@@ -477,7 +477,7 @@ if command -v crontab &> /dev/null; then
             crontab -u "$CRON_USER" -l 2>/dev/null >> "$RESULTS_FILE"
         else
             CRON_READ_ERR=$?
-            if [ $CRON_READ_ERR -eq 1 ]; then
+            if [ "$CRON_READ_ERR" -eq 1 ]; then
                 test_info "User $CRON_USER has no crontab (this is OK - means empty)"
             else
                 test_warn "Cannot read crontab for $CRON_USER (exit code: $CRON_READ_ERR)"
@@ -511,7 +511,7 @@ if command -v crontab &> /dev/null; then
     fi
 
     # Test plesk bin cron if available
-    if [ $HAS_PLESK_CRON -eq 1 ] && [ -n "$TEST_DOMAIN" ]; then
+    if [ "$HAS_PLESK_CRON" -eq 1 ] && [ -n "$TEST_DOMAIN" ]; then
         test_info "Testing Plesk cron management for domain: $TEST_DOMAIN"
 
         # Try to list cron jobs via plesk
@@ -535,7 +535,7 @@ if command -v crontab &> /dev/null; then
     if [ -n "$CRON_USER" ]; then
         echo "RECOMMENDED: Use standard crontab -u $CRON_USER for cron jobs" >> "$RESULTS_FILE"
     fi
-    if [ $HAS_PLESK_CRON -eq 1 ]; then
+    if [ "$HAS_PLESK_CRON" -eq 1 ]; then
         echo "ALTERNATIVE: Plesk bin cron available but may be for web UI management only" >> "$RESULTS_FILE"
     fi