cmd/swarm: fix TestConfigFileOverrides

cmd/swarm/config.go

@@ -179,8 +179,10 @@ func cmdLineOverride(currentConfig *bzzapi.Config, ctx *cli.Context) *bzzapi.Con
 		if err != nil {
 			utils.Fatalf("invalid cli flag %s: %v", SwarmNetworkIdFlag.Name, err)
 		}
+		if id != 0 {
 			currentConfig.NetworkID = id
 		}
+	}
 
 	if ctx.GlobalIsSet(utils.DataDirFlag.Name) {
 		if datadir := ctx.GlobalString(utils.DataDirFlag.Name); datadir != "" {
@@ -272,8 +274,10 @@ func envVarsOverride(currentConfig *bzzapi.Config) (config *bzzapi.Config) {
 		if err != nil {
 			utils.Fatalf("invalid environment variable %s: %v", SWARM_ENV_NETWORK_ID, err)
 		}
+		if id != 0 {
 			currentConfig.NetworkID = id
 		}
+	}
 
 	if datadir := os.Getenv(GETH_ENV_DATADIR); datadir != "" {
 		currentConfig.Path = expandPath(datadir)

cmd/swarm/main.go

@@ -95,7 +95,6 @@ var (
 		Name:   "bzznetworkid",
 		Usage:  "Network identifier (integer, default 3=swarm testnet)",
 		EnvVar: SWARM_ENV_NETWORK_ID,
-		Value:  3,
 	}
 	SwarmSwapEnabledFlag = cli.BoolFlag{
 		Name:   "swap",