cmd, node: dump empty value config (#21296)

cmd/utils/flags.go

@@ -905,12 +905,15 @@ func setNAT(ctx *cli.Context, cfg *p2p.Config) {
 
 // splitAndTrim splits input separated by a comma
 // and trims excessive white space from the substrings.
-func splitAndTrim(input string) []string {
-	result := strings.Split(input, ",")
-	for i, r := range result {
-		result[i] = strings.TrimSpace(r)
+func splitAndTrim(input string) (ret []string) {
+	l := strings.Split(input, ",")
+	for _, r := range l {
+		r = strings.TrimSpace(r)
+		if len(r) > 0 {
+			ret = append(ret, r)
+		}
 	}
-	return result
+	return ret
 }
 
 // setHTTP creates the HTTP RPC listener interface string from the set