From 724f6e0969330677ebf5e0fb78ba36086548af3f Mon Sep 17 00:00:00 2001
From: yyforyongyu <yy2452@columbia.edu>
Date: Thu, 3 Sep 2020 03:15:04 +0800
Subject: [PATCH] itest: require no error when cleaning up chainbackends

---
 lntest/bitcoind.go       | 24 ++++++++++++++++++------
 lntest/btcd.go           | 20 +++++++++++++++-----
 lntest/itest/lnd_test.go |  6 +++++-
 lntest/neutrino.go       |  4 ++--
 4 files changed, 40 insertions(+), 14 deletions(-)

diff --git a/lntest/bitcoind.go b/lntest/bitcoind.go
index 0a73c86e..86d59ef4 100644
--- a/lntest/bitcoind.go
+++ b/lntest/bitcoind.go
@@ -3,6 +3,7 @@
 package lntest
 
 import (
+	"errors"
 	"fmt"
 	"io/ioutil"
 	"math/rand"
@@ -71,7 +72,7 @@ func (b BitcoindBackendConfig) Name() string {
 // NewBackend starts a bitcoind node and returns a BitoindBackendConfig for
 // that node.
 func NewBackend(miner string, netParams *chaincfg.Params) (
-	*BitcoindBackendConfig, func(), error) {
+	*BitcoindBackendConfig, func() error, error) {
 
 	if netParams != &chaincfg.RegressionNetParams {
 		return nil, nil, fmt.Errorf("only regtest supported")
@@ -121,21 +122,32 @@ func NewBackend(miner string, netParams *chaincfg.Params) (
 		return nil, nil, fmt.Errorf("couldn't start bitcoind: %v", err)
 	}
 
-	cleanUp := func() {
+	cleanUp := func() error {
 		bitcoind.Process.Kill()
 		bitcoind.Wait()
 
+		var errStr string
 		// After shutting down the chain backend, we'll make a copy of
 		// the log file before deleting the temporary log dir.
 		err := CopyFile("./output_bitcoind_chainbackend.log", logFile)
 		if err != nil {
-			fmt.Printf("unable to copy file: %v\n", err)
+			errStr += fmt.Sprintf("unable to copy file: %v\n", err)
 		}
 		if err = os.RemoveAll(logDir); err != nil {
-			fmt.Printf("Cannot remove dir %s: %v\n", logDir, err)
+			errStr += fmt.Sprintf(
+				"cannot remove dir %s: %v\n", logDir, err,
+			)
 		}
-
-		os.RemoveAll(tempBitcoindDir)
+		if err := os.RemoveAll(tempBitcoindDir); err != nil {
+			errStr += fmt.Sprintf(
+				"cannot remove dir %s: %v\n",
+				tempBitcoindDir, err,
+			)
+		}
+		if errStr != "" {
+			return errors.New(errStr)
+		}
+		return nil
 	}
 
 	// Allow process to start.
diff --git a/lntest/btcd.go b/lntest/btcd.go
index 2322d8ee..3b75b7bc 100644
--- a/lntest/btcd.go
+++ b/lntest/btcd.go
@@ -4,6 +4,7 @@ package lntest
 
 import (
 	"encoding/hex"
+	"errors"
 	"fmt"
 	"os"
 
@@ -72,7 +73,7 @@ func (b BtcdBackendConfig) Name() string {
 // that node. miner should be set to the P2P address of the miner to connect
 // to.
 func NewBackend(miner string, netParams *chaincfg.Params) (
-	*BtcdBackendConfig, func(), error) {
+	*BtcdBackendConfig, func() error, error) {
 
 	args := []string{
 		"--rejectnonstd",
@@ -98,19 +99,28 @@ func NewBackend(miner string, netParams *chaincfg.Params) (
 		minerAddr: miner,
 	}
 
-	cleanUp := func() {
-		chainBackend.TearDown()
+	cleanUp := func() error {
+		var errStr string
+		if err := chainBackend.TearDown(); err != nil {
+			errStr += err.Error() + "\n"
+		}
 
 		// After shutting down the chain backend, we'll make a copy of
 		// the log file before deleting the temporary log dir.
 		logFile := logDir + "/" + netParams.Name + "/btcd.log"
 		err := CopyFile("./output_btcd_chainbackend.log", logFile)
 		if err != nil {
-			fmt.Printf("unable to copy file: %v\n", err)
+			errStr += fmt.Sprintf("unable to copy file: %v\n", err)
 		}
 		if err = os.RemoveAll(logDir); err != nil {
-			fmt.Printf("Cannot remove dir %s: %v\n", logDir, err)
+			errStr += fmt.Sprintf(
+				"cannot remove dir %s: %v\n", logDir, err,
+			)
 		}
+		if errStr != "" {
+			return errors.New(errStr)
+		}
+		return nil
 	}
 
 	return bd, cleanUp, nil
diff --git a/lntest/itest/lnd_test.go b/lntest/itest/lnd_test.go
index 8a094b3b..a8589450 100644
--- a/lntest/itest/lnd_test.go
+++ b/lntest/itest/lnd_test.go
@@ -14445,7 +14445,11 @@ func TestLightningNetworkDaemon(t *testing.T) {
 	if err != nil {
 		ht.Fatalf("unable to start backend: %v", err)
 	}
-	defer cleanUp()
+	defer func() {
+		require.NoError(
+			t, cleanUp(), "failed to clean up chain backend",
+		)
+	}()
 
 	if err := miner.SetUp(true, 50); err != nil {
 		ht.Fatalf("unable to set up mining node: %v", err)
diff --git a/lntest/neutrino.go b/lntest/neutrino.go
index 1a5497b9..25f2af24 100644
--- a/lntest/neutrino.go
+++ b/lntest/neutrino.go
@@ -44,12 +44,12 @@ func (b NeutrinoBackendConfig) Name() string {
 
 // NewBackend starts and returns a NeutrinoBackendConfig for the node.
 func NewBackend(miner string, _ *chaincfg.Params) (
-	*NeutrinoBackendConfig, func(), error) {
+	*NeutrinoBackendConfig, func() error, error) {
 
 	bd := &NeutrinoBackendConfig{
 		minerAddr: miner,
 	}
 
-	cleanUp := func() {}
+	cleanUp := func() error { return nil }
 	return bd, cleanUp, nil
 }