multi: update linter, fix issues

.golangci.yml

@@ -76,6 +76,9 @@ linters:
   - golint
   - maligned
   - scopelint
+  - varcheck
+  - structcheck
+  - deadcode
   
   # New linters that need a code adjustment first.
   - wrapcheck
@@ -107,6 +110,10 @@ linters:
   - stylecheck
   - thelper
   - revive
+  - tagalign
+  - depguard
+  - nosnakecase
+  - interfacebloat
   
   # Additions compared to LND
   - exhaustruct
@@ -122,6 +129,10 @@ issues:
         linters:
           - forbidigo
           - unparam
+          - gosec
+      - path: _mock\.go
+        linters:
+          - gosec
         
       # Allow fmt.Printf() in loopd
       - path: cmd/loopd/*

client.go

@@ -204,6 +204,8 @@ func (s *Client) FetchSwaps(ctx context.Context) ([]*SwapInfo, error) {
 	swaps := make([]*SwapInfo, 0, len(loopInSwaps)+len(loopOutSwaps))
 
 	for _, swp := range loopOutSwaps {
+		swp := swp
+
 		swapInfo := &SwapInfo{
 			SwapType:      swap.TypeOut,
 			SwapContract:  swp.Contract.SwapContract,
@@ -235,6 +237,8 @@ func (s *Client) FetchSwaps(ctx context.Context) ([]*SwapInfo, error) {
 	}
 
 	for _, swp := range loopInSwaps {
+		swp := swp
+
 		swapInfo := &SwapInfo{
 			SwapType:      swap.TypeIn,
 			SwapContract:  swp.Contract.SwapContract,

fsm/fsm_test.go

@@ -88,8 +88,9 @@ func TestStateMachine_ActionError(t *testing.T) {
 
 	// Add a Transition to State2 if the Action on Stat2 fails.
 	// The new StateMap looks like this:
-	// State1 -> Event1 -> State2
-	// State2 -> OnError -> ErrorState
+	// 	State1 -> Event1 -> State2
+	//
+	// 	State2 -> OnError -> ErrorState
 	states["State2"] = State{
 		Action: ctx.errorAction,
 		Transitions: Transitions{

liquidity/autoloop_test.go

@@ -984,7 +984,7 @@ func TestAutoloopBothTypes(t *testing.T) {
 				Events: []*loopdb.LoopEvent{
 					{
 						SwapStateData: loopdb.SwapStateData{
-							State: loopdb.SwapState(loopdb.StateSuccess),
+							State: loopdb.StateSuccess,
 						},
 					},
 				},
@@ -1168,7 +1168,7 @@ func TestAutoLoopRecurringBudget(t *testing.T) {
 				Events: []*loopdb.LoopEvent{
 					{
 						SwapStateData: loopdb.SwapStateData{
-							State: loopdb.SwapState(loopdb.StateSuccess),
+							State: loopdb.StateSuccess,
 						},
 					},
 				},

liquidity/fees.go

@@ -349,7 +349,7 @@ func (f *FeePortion) loopOutLimits(swapAmt btcutil.Amount,
 	// multiplier from the miner fees. We do this because we want to
 	// consider the average case for our budget calculations and not the
 	// severe edge-case miner fees.
-	miner = miner / maxMinerMultiplier
+	miner /= maxMinerMultiplier
 
 	// Calculate the worst case fees that we could pay for this swap,
 	// ensuring that we are within our fee limit even if the swap fails.

liquidity/liquidity.go

@@ -536,10 +536,7 @@ func (m *Manager) dispatchBestEasyAutoloopSwap(ctx context.Context) error {
 
 	// Get a summary of our existing swaps so that we can check our autoloop
 	// budget.
-	summary, err := m.checkExistingAutoLoops(ctx, loopOut, loopIn)
-	if err != nil {
-		return err
-	}
+	summary := m.checkExistingAutoLoops(ctx, loopOut, loopIn)
 
 	err = m.checkSummaryBudget(summary)
 	if err != nil {
@@ -581,7 +578,7 @@ func (m *Manager) dispatchBestEasyAutoloopSwap(ctx context.Context) error {
 	// allowed clamp it to max.
 	amount := localTotal - m.params.EasyAutoloopTarget
 	if amount > restrictions.Maximum {
-		amount = btcutil.Amount(restrictions.Maximum)
+		amount = restrictions.Maximum
 	}
 
 	// If the amount we want to loop out is less than the minimum we can't
@@ -601,7 +598,7 @@ func (m *Manager) dispatchBestEasyAutoloopSwap(ctx context.Context) error {
 	builder := newLoopOutBuilder(m.cfg)
 
 	channel := m.pickEasyAutoloopChannel(
-		channels, restrictions, loopOut, loopIn, amount,
+		channels, restrictions, loopOut, loopIn,
 	)
 	if channel == nil {
 		return fmt.Errorf("no eligible channel for easy autoloop")
@@ -624,12 +621,12 @@ func (m *Manager) dispatchBestEasyAutoloopSwap(ctx context.Context) error {
 	switch feeLimit := easyParams.FeeLimit.(type) {
 	case *FeePortion:
 		if feeLimit.PartsPerMillion == 0 {
-			feeLimit = &FeePortion{
+			easyParams.FeeLimit = &FeePortion{
 				PartsPerMillion: defaultFeePPM,
 			}
 		}
 	default:
-		feeLimit = &FeePortion{
+		easyParams.FeeLimit = &FeePortion{
 			PartsPerMillion: defaultFeePPM,
 		}
 	}
@@ -646,16 +643,16 @@ func (m *Manager) dispatchBestEasyAutoloopSwap(ctx context.Context) error {
 		return err
 	}
 
-	swap := loop.OutRequest{}
+	var swp loop.OutRequest
 	if t, ok := suggestion.(*loopOutSwapSuggestion); ok {
-		swap = t.OutRequest
+		swp = t.OutRequest
 	} else {
 		return fmt.Errorf("unexpected swap suggestion type: %T", t)
 	}
 
 	// Dispatch a sticky loop out.
 	go m.dispatchStickyLoopOut(
-		ctx, swap, defaultAmountBackoffRetry, defaultAmountBackoff,
+		ctx, swp, defaultAmountBackoffRetry, defaultAmountBackoff,
 	)
 
 	return nil
@@ -762,10 +759,7 @@ func (m *Manager) SuggestSwaps(ctx context.Context) (
 
 	// Get a summary of our existing swaps so that we can check our autoloop
 	// budget.
-	summary, err := m.checkExistingAutoLoops(ctx, loopOut, loopIn)
-	if err != nil {
-		return nil, err
-	}
+	summary := m.checkExistingAutoLoops(ctx, loopOut, loopIn)
 
 	err = m.checkSummaryBudget(summary)
 	if err != nil {
@@ -1074,9 +1068,9 @@ func (e *existingAutoLoopSummary) totalFees() btcutil.Amount {
 // automatically dispatched swaps that have completed, and the worst-case fee
 // total for our set of ongoing, automatically dispatched swaps as well as a
 // current in-flight count.
-func (m *Manager) checkExistingAutoLoops(ctx context.Context,
-	loopOuts []*loopdb.LoopOut, loopIns []*loopdb.LoopIn) (
-	*existingAutoLoopSummary, error) {
+func (m *Manager) checkExistingAutoLoops(_ context.Context,
+	loopOuts []*loopdb.LoopOut,
+	loopIns []*loopdb.LoopIn) *existingAutoLoopSummary {
 
 	var summary existingAutoLoopSummary
 
@@ -1133,7 +1127,7 @@ func (m *Manager) checkExistingAutoLoops(ctx context.Context,
 		}
 	}
 
-	return &summary, nil
+	return &summary
 }
 
 // currentSwapTraffic examines our existing swaps and returns a summary of the
@@ -1416,7 +1410,7 @@ func (m *Manager) waitForSwapPayment(ctx context.Context, swapHash lntypes.Hash,
 // swap conflicts.
 func (m *Manager) pickEasyAutoloopChannel(channels []lndclient.ChannelInfo,
 	restrictions *Restrictions, loopOut []*loopdb.LoopOut,
-	loopIn []*loopdb.LoopIn, amount btcutil.Amount) *lndclient.ChannelInfo {
+	loopIn []*loopdb.LoopIn) *lndclient.ChannelInfo {
 
 	traffic := m.currentSwapTraffic(loopOut, loopIn)
 
@@ -1472,7 +1466,6 @@ func (m *Manager) numActiveStickyLoops() int {
 	defer m.activeStickyLock.Unlock()
 
 	return m.activeStickyLoops
-
 }
 
 func (m *Manager) checkSummaryBudget(summary *existingAutoLoopSummary) error {
@@ -1482,7 +1475,6 @@ func (m *Manager) checkSummaryBudget(summary *existingAutoLoopSummary) error {
 			"(upper limit)",
 			m.params.AutoFeeBudget, summary.spentFees,
 			summary.pendingFees)
-
 	}
 
 	return nil
@@ -1556,7 +1548,3 @@ func satPerKwToSatPerVByte(satPerKw chainfee.SatPerKWeight) int64 {
 func ppmToSat(amount btcutil.Amount, ppm uint64) btcutil.Amount {
 	return btcutil.Amount(uint64(amount) * ppm / FeeBase)
 }
-
-func mSatToSatoshis(amount lnwire.MilliSatoshi) btcutil.Amount {
-	return btcutil.Amount(amount / 1000)
-}

liquidity/parameters.go

@@ -3,13 +3,13 @@ package liquidity
 import (
 	"errors"
 	"fmt"
-	"github.com/lightningnetwork/lnd/lnrpc/walletrpc"
 	"strings"
 	"time"
 
 	"github.com/btcsuite/btcd/btcutil"
 	"github.com/lightninglabs/lndclient"
 	"github.com/lightninglabs/loop/swap"
+	"github.com/lightningnetwork/lnd/lnrpc/walletrpc"
 	"github.com/lightningnetwork/lnd/lnwallet/chainfee"
 	"github.com/lightningnetwork/lnd/lnwire"
 	"github.com/lightningnetwork/lnd/routing/route"
@@ -527,7 +527,6 @@ func ParametersToRpc(cfg Parameters) (*clientrpc.LiquidityParameters,
 
 	default:
 		addrType = clientrpc.AddressType_ADDRESS_TYPE_UNKNOWN
-
 	}
 
 	rpcCfg := &clientrpc.LiquidityParameters{

liquidity/threshold_rule.go

@@ -127,10 +127,10 @@ func (r *ThresholdRule) swapAmount(channel *balances,
 // This function can be used for loop out or loop in, but the concept is the
 // same - we want liquidity in one (target) direction, while preserving some
 // minimum in the other (reserve) direction.
-// * target: this is the side of the channel(s) where we want to acquire some
-//   liquidity. We aim for this liquidity to reach the threshold amount set.
-// * reserve: this is the side of the channel(s) that we will move liquidity
-//   away from. This may not drop below a certain reserve threshold.
+//   - target: this is the side of the channel(s) where we want to acquire some
+//     liquidity. We aim for this liquidity to reach the threshold amount set.
+//   - reserve: this is the side of the channel(s) that we will move liquidity
+//     away from. This may not drop below a certain reserve threshold.
 func calculateSwapAmount(targetAmount, reserveAmount,
 	capacity btcutil.Amount, targetThresholdPercentage,
 	reserveThresholdPercentage uint64) btcutil.Amount {

loopd/daemon.go

@@ -10,6 +10,7 @@ import (
 	"strings"
 	"sync"
 	"sync/atomic"
+	"time"
 
 	"github.com/coreos/bbolt"
 	proxy "github.com/grpc-ecosystem/grpc-gateway/v2/runtime"
@@ -302,7 +303,10 @@ func (d *Daemon) startWebServers() error {
 	if d.restListener != nil {
 		log.Infof("Starting REST proxy listener")
 
-		d.restServer = &http.Server{Handler: restHandler}
+		d.restServer = &http.Server{
+			Handler:           restHandler,
+			ReadHeaderTimeout: 5 * time.Second,
+		}
 
 		d.wg.Add(1)
 		go func() {

loopd/migration.go

@@ -61,7 +61,7 @@ func migrateBoltdb(ctx context.Context, cfg *Config) error {
 		return err
 	}
 
-	// If the migration was successfull we'll rename the bolt db to
+	// If the migration was successful we'll rename the bolt db to
 	// loop.db.bk.
 	err = os.Rename(
 		filepath.Join(cfg.DataDir, "loop.db"),

loopd/view.go

@@ -49,6 +49,8 @@ func viewOut(swapClient *loop.Client, chainParams *chaincfg.Params) error {
 	}
 
 	for _, s := range swaps {
+		s := s
+
 		htlc, err := loop.GetHtlc(
 			s.Hash, &s.Contract.SwapContract, chainParams,
 		)
@@ -98,6 +100,8 @@ func viewIn(swapClient *loop.Client, chainParams *chaincfg.Params) error {
 	}
 
 	for _, s := range swaps {
+		s := s
+
 		htlc, err := loop.GetHtlc(
 			s.Hash, &s.Contract.SwapContract, chainParams,
 		)

loopdb/migrate.go

@@ -142,7 +142,7 @@ func (m *MigratorManager) migrateLoopIns(ctx context.Context) error {
 	swapMap := make(map[lntypes.Hash]*LoopInContract)
 	updateMap := make(map[lntypes.Hash][]BatchInsertUpdateData)
 
-	// For each loop in, create a new loop in in the toStore.
+	// For each loop in, create a new loop in the toStore.
 	for _, loopIn := range loopIns {
 		swapMap[loopIn.Hash] = loopIn.Contract
 
@@ -311,6 +311,7 @@ func (m *MigratorManager) checkLiquidityParams(ctx context.Context) error {
 func equalizeLoopOut(fromLoopOut, toLoopOut *LoopOut) error {
 	if fromLoopOut.Contract.InitiationTime.Unix() !=
 		toLoopOut.Contract.InitiationTime.Unix() {
+
 		return fmt.Errorf("initiation time mismatch")
 	}
 
@@ -318,6 +319,7 @@ func equalizeLoopOut(fromLoopOut, toLoopOut *LoopOut) error {
 
 	if fromLoopOut.Contract.SwapPublicationDeadline.Unix() !=
 		toLoopOut.Contract.SwapPublicationDeadline.Unix() {
+
 		return fmt.Errorf("swap publication deadline mismatch")
 	}
 
@@ -337,6 +339,7 @@ func equalizeLoopOut(fromLoopOut, toLoopOut *LoopOut) error {
 func equalizeLoopIns(fromLoopIn, toLoopIn *LoopIn) error {
 	if fromLoopIn.Contract.InitiationTime.Unix() !=
 		toLoopIn.Contract.InitiationTime.Unix() {
+
 		return fmt.Errorf("initiation time mismatch")
 	}
 
@@ -398,17 +401,6 @@ func equalValues(src interface{}, dst interface{}) error {
 	return nil
 }
 
-func elementsMatch(src interface{}, dst interface{}) error {
-	mt := &mockTesting{}
-
-	require.ElementsMatch(mt, src, dst)
-	if mt.fail || mt.failNow {
-		return fmt.Errorf(mt.format, mt.args)
-	}
-
-	return nil
-}
-
 type mockTesting struct {
 	failNow bool
 	fail    bool

loopdb/migrations.go

@@ -108,7 +108,7 @@ func newReplacerFile(parent fs.File, replaces map[string]string) (*replacerFile,
 
 	contentStr := string(content)
 	for from, to := range replaces {
-		contentStr = strings.Replace(contentStr, from, to, -1)
+		contentStr = strings.ReplaceAll(contentStr, from, to)
 	}
 
 	var buf bytes.Buffer

loopdb/raw_db_test.go

@@ -14,12 +14,12 @@ import (
 //
 // Example output:
 //
-// map[string]interface{}{
-//      Hex("1234"): map[string]interface{}{
-//              "human-readable": Hex("102030"),
-//              Hex("1111"): Hex("5783492373"),
-//      },
-// } .
+//	map[string]interface{}{
+//	     Hex("1234"): map[string]interface{}{
+//	             "human-readable": Hex("102030"),
+//	             Hex("1111"): Hex("5783492373"),
+//	     },
+//	} .
 func DumpDB(tx *bbolt.Tx) error { // nolint: unused
 	return tx.ForEach(func(k []byte, bucket *bbolt.Bucket) error {
 		key := toString(k)

loopdb/sql_store.go

@@ -133,6 +133,8 @@ func (s *BaseDB) BatchCreateLoopOut(ctx context.Context,
 	writeOpts := &SqliteTxOptions{}
 	return s.ExecTx(ctx, writeOpts, func(tx *sqlc.Queries) error {
 		for swapHash, swap := range swaps {
+			swap := swap
+
 			insertArgs := loopToInsertArgs(
 				swapHash, &swap.SwapContract,
 			)
@@ -250,13 +252,15 @@ func (s *BaseDB) CreateLoopIn(ctx context.Context, hash lntypes.Hash,
 	})
 }
 
-// BatchCreateLoopOut adds multiple initiated swaps to the store.
+// BatchCreateLoopIn adds multiple initiated swaps to the store.
 func (s *BaseDB) BatchCreateLoopIn(ctx context.Context,
 	swaps map[lntypes.Hash]*LoopInContract) error {
 
 	writeOpts := &SqliteTxOptions{}
 	return s.ExecTx(ctx, writeOpts, func(tx *sqlc.Queries) error {
 		for swapHash, swap := range swaps {
+			swap := swap
+
 			insertArgs := loopToInsertArgs(
 				swapHash, &swap.SwapContract,
 			)
@@ -422,6 +426,7 @@ func loopToInsertArgs(hash lntypes.Hash,
 // needed to insert it into the database.
 func loopOutToInsertArgs(hash lntypes.Hash,
 	loopOut *LoopOutContract) sqlc.InsertLoopOutParams {
+
 	return sqlc.InsertLoopOutParams{
 		SwapHash:            hash[:],
 		DestAddress:         loopOut.DestAddr.String(),
@@ -458,6 +463,7 @@ func loopInToInsertArgs(hash lntypes.Hash,
 // and converts them to the arguments needed to insert them into the database.
 func swapToHtlcKeysInsertArgs(hash lntypes.Hash,
 	swap *SwapContract) sqlc.InsertHtlcKeysParams {
+
 	return sqlc.InsertHtlcKeysParams{
 		SwapHash:               hash[:],
 		SenderScriptPubkey:     swap.HtlcKeys.SenderScriptKey[:],

loopdb/sql_test.go

@@ -17,9 +17,8 @@ import (
 	"github.com/stretchr/testify/require"
 )
 
-var (
-	testTime1 = time.Date(2018, time.January, 9, 14, 54, 32, 3, time.UTC)
-	testTime2 = time.Date(2018, time.January, 9, 15, 02, 03, 5, time.UTC)
+const (
+	testLabel = "test label"
 )
 
 // TestSqliteLoopOutStore tests all the basic functionality of the current
@@ -75,7 +74,7 @@ func TestSqliteLoopOutStore(t *testing.T) {
 	})
 
 	labelledSwap := unrestrictedSwap
-	labelledSwap.Label = "test label"
+	labelledSwap.Label = testLabel
 	t.Run("labelled swap", func(t *testing.T) {
 		testSqliteLoopOutStore(t, &labelledSwap)
 	})
@@ -206,7 +205,7 @@ func TestSQLliteLoopInStore(t *testing.T) {
 	})
 
 	labelledSwap := pendingSwap
-	labelledSwap.Label = "test label"
+	labelledSwap.Label = testLabel
 	t.Run("loop in with label", func(t *testing.T) {
 		testSqliteLoopInStore(t, labelledSwap)
 	})
@@ -310,12 +309,12 @@ func TestSqliteLiquidityParams(t *testing.T) {
 // convert between the :one and :many types from sqlc.
 func TestSqliteTypeConversion(t *testing.T) {
 	loopOutSwapRow := sqlc.GetLoopOutSwapRow{}
-	randomStruct(&loopOutSwapRow)
+	err := randomStruct(&loopOutSwapRow)
+	require.NoError(t, err)
 	require.NotNil(t, loopOutSwapRow.DestAddress)
 
 	loopOutSwapsRow := sqlc.GetLoopOutSwapsRow(loopOutSwapRow)
 	require.EqualValues(t, loopOutSwapRow, loopOutSwapsRow)
-
 }
 
 // TestIssue615 tests that on faulty timestamps, the database will be fixed.

loopdb/sqlite.go

@@ -211,7 +211,6 @@ func (db *BaseDB) ExecTx(ctx context.Context, txOptions TxOptions,
 // FixFaultyTimestamps fixes faulty timestamps in the database, caused
 // by using milliseconds instead of seconds as the publication deadline.
 func (b *BaseDB) FixFaultyTimestamps(ctx context.Context) error {
-
 	// Manually fetch all the loop out swaps.
 	rows, err := b.DB.QueryContext(
 		ctx, "SELECT swap_hash, publication_deadline FROM loopout_swaps",
@@ -219,6 +218,9 @@ func (b *BaseDB) FixFaultyTimestamps(ctx context.Context) error {
 	if err != nil {
 		return err
 	}
+	defer func() {
+		_ = rows.Close()
+	}()
 
 	// Parse the rows into a struct. We need to do this manually because
 	// the sqlite driver will fail on faulty timestamps.
@@ -241,14 +243,19 @@ func (b *BaseDB) FixFaultyTimestamps(ctx context.Context) error {
 		loopOutSwaps = append(loopOutSwaps, swap)
 	}
 
+	if err := rows.Err(); err != nil {
+		return err
+	}
+
 	tx, err := b.BeginTx(ctx, &SqliteTxOptions{})
 	if err != nil {
 		return err
 	}
-	defer tx.Rollback() //nolint: errcheck
+	defer func() {
+		_ = tx.Rollback()
+	}()
 
 	for _, swap := range loopOutSwaps {
-
 		// Get the year of the timestamp.
 		year, err := getTimeStampYear(swap.PublicationDeadline)
 		if err != nil {
@@ -300,7 +307,7 @@ type SqliteTxOptions struct {
 	readOnly bool
 }
 
-// NewKeyStoreReadOpts returns a new KeyStoreTxOptions instance triggers a read
+// NewSqlReadOpts returns a new KeyStoreTxOptions instance triggers a read
 // transaction.
 func NewSqlReadOpts() *SqliteTxOptions {
 	return &SqliteTxOptions{
@@ -310,7 +317,7 @@ func NewSqlReadOpts() *SqliteTxOptions {
 
 // ReadOnly returns true if the transaction should be read only.
 //
-// NOTE: This implements the TxOptions
+// NOTE: This implements the TxOptions interface.
 func (r *SqliteTxOptions) ReadOnly() bool {
 	return r.readOnly
 }

loopdb/store_test.go

@@ -105,7 +105,7 @@ func TestLoopOutStore(t *testing.T) {
 	})
 
 	labelledSwap := unrestrictedSwap
-	labelledSwap.Label = "test label"
+	labelledSwap.Label = testLabel
 	t.Run("labelled swap", func(t *testing.T) {
 		testLoopOutStore(t, &labelledSwap)
 	})
@@ -249,7 +249,7 @@ func TestLoopInStore(t *testing.T) {
 	})
 
 	labelledSwap := pendingSwap
-	labelledSwap.Label = "test label"
+	labelledSwap.Label = testLabel
 	t.Run("loop in with label", func(t *testing.T) {
 		testLoopInStore(t, labelledSwap)
 	})

loopout_test.go

@@ -682,7 +682,7 @@ func testPreimagePush(t *testing.T) {
 	sweepTx := ctx.ReceiveTx()
 
 	// Finally, we put this swap out of its misery and notify a successful
-	// spend our our sweepTx and assert that the swap succeeds.
+	// spend our sweepTx and assert that the swap succeeds.
 	ctx.NotifySpend(sweepTx, 0)
 
 	cfg.store.(*storeMock).assertLoopOutState(loopdb.StateSuccess)
@@ -1007,7 +1007,7 @@ func TestLoopOutMuSig2Sweep(t *testing.T) {
 	require.Len(t, sweepTx.TxIn[0].Witness, 1)
 
 	// Finally, we put this swap out of its misery and notify a successful
-	// spend our our sweepTx and assert that the swap succeeds.
+	// spend our sweepTx and assert that the swap succeeds.
 	ctx.NotifySpend(sweepTx, 0)
 
 	cfg.store.(*storeMock).assertLoopOutState(loopdb.StateSuccess)

swap/log.go

@@ -25,8 +25,8 @@ func (s *PrefixLog) Infof(format string, params ...interface{}) {
 	)
 }
 
-// Warnf formats message according to format specifier and writes to
-// to log with LevelError.
+// Warnf formats message according to format specifier and writes to log with
+// LevelError.
 func (s *PrefixLog) Warnf(format string, params ...interface{}) {
 	s.Logger.Warnf(
 		fmt.Sprintf("%v %s", ShortHash(&s.Hash), format),
@@ -34,8 +34,8 @@ func (s *PrefixLog) Warnf(format string, params ...interface{}) {
 	)
 }
 
-// Errorf formats message according to format specifier and writes to
-// to log with LevelError.
+// Errorf formats message according to format specifier and writes to log with
+// LevelError.
 func (s *PrefixLog) Errorf(format string, params ...interface{}) {
 	s.Logger.Errorf(
 		fmt.Sprintf("%v %s", ShortHash(&s.Hash), format),

test/log.go

@@ -18,7 +18,7 @@ var (
 // the write-end pipe of an initialized log rotator.
 type logWriter struct{}
 
-func (logWriter) Write(p []byte) (n int, err error) {
+func (logWriter) Write(p []byte) (int, error) {
 	os.Stdout.Write(p)
 	return len(p), nil
 }

tools/Dockerfile

@@ -1,8 +1,9 @@
-FROM golang:1.18
+FROM golang:1.21
 
 RUN apt-get update && apt-get install -y git
 ENV GOCACHE=/tmp/build/.cache
 ENV GOMODCACHE=/tmp/build/.modcache
+ENV GOFLAGS="-buildvcs=false"
 
 COPY . /tmp/tools
 
@@ -10,8 +11,6 @@ RUN cd /tmp \
   && mkdir -p /tmp/build/.cache \
   && mkdir -p /tmp/build/.modcache \
   && cd /tmp/tools \
-  && go install -trimpath -tags=tools github.com/golangci/golangci-lint/cmd/golangci-lint \
-  && chmod -R 777 /tmp/build/ \
-  && git config --global --add safe.directory /build
-
+  && go install -trimpath github.com/golangci/golangci-lint/cmd/golangci-lint \
+  && chmod -R 777 /tmp/build/
 WORKDIR /build

tools/go.mod

@@ -3,6 +3,6 @@ module github.com/lightninglabs/loop/tools
 go 1.16
 
 require (
-	github.com/golangci/golangci-lint v1.46.2 // indirect
-	github.com/rinchsan/gosimports v0.1.5 // indirect
+	github.com/golangci/golangci-lint v1.54.2
+	github.com/rinchsan/gosimports v0.1.5
 )

utils.go

@@ -387,6 +387,8 @@ func invoicesrpcSelectHopHints(amtMSat lnwire.MilliSatoshi, cfg *SelectHopHintsC
 	hopHintChans := make(map[wire.OutPoint]struct{})
 	hopHints := make([][]zpay32.HopHint, 0, numMaxHophints)
 	for _, channel := range openChannels {
+		channel := channel
+
 		enoughHopHints := sufficientHints(
 			len(hopHints), numMaxHophints, hopHintFactor, amtMSat,
 			totalHintBandwidth,