remove redundancy

server/start.go

@@ -6,6 +6,7 @@ import (
 	"bufio"
 	"errors"
 	"fmt"
+	"io"
 	"net"
 	"net/http"
 	"os"
@@ -280,7 +281,7 @@ func startInProcess(ctx *Context, clientCtx client.Context, appCreator types.App
 	var app types.Application
 
 	if isTestnet, ok := ctx.Viper.Get(KeyIsTestnet).(bool); ok && isTestnet {
-		app, err = testnetify(ctx, home, appCreator, db)
+		app, err = testnetify(ctx, home, appCreator, db, traceWriter)
 		if err != nil {
 			return err
 		}
@@ -669,20 +670,14 @@ before stopping the daemon.
 
 // testnetify modifies both state and blockStore, allowing the provided operator address and local validator key to control the network
 // that the state in the data folder represents. The chainID of the local genesis file is modified to match the provided chainID.
-func testnetify(ctx *Context, home string, testnetAppCreator types.AppCreator, db db.DB) (types.Application, error) {
+func testnetify(ctx *Context, home string, testnetAppCreator types.AppCreator, db db.DB, traceWriter io.WriteCloser) (types.Application, error) {
 	config := ctx.Config
 
 	newChainID, ok := ctx.Viper.Get(KeyNewChainID).(string)
 	if !ok {
 		return nil, fmt.Errorf("expected string for key %s", KeyNewChainID)
 	}
 
-	traceWriterFile := ctx.Viper.GetString(flagTraceStore)
-	traceWriter, err := openTraceWriter(traceWriterFile)
-	if err != nil {
-		return nil, err
-	}
-
 	genDocProvider := node.DefaultGenesisDocProviderFunc(config)
 
 	// Initialize blockStore and stateDB.