multi: fix linter issues

This commit fixes outstanding linter issues, that we're not found by
running `make lint` locally. The linter issues were found by running
`docker run -v $(pwd):/build loop-tools golangci-lint run --whole-files`

I added the `revive` to the excludes as it would be to much of a
refactor and IMO seems unneccesary. E.g.
`interface.go:222:6: exported: type name will be used as
loop.LoopInTerms by other packages, and that stutters; consider
 calling this InTerms (revive)`. I think `loop.LoopInTerms` is fine.

Author: sputn1ck

.golangci.yml

@@ -106,7 +106,8 @@ linters:
   - nilnil
   - stylecheck
   - thelper
-
+  - revive
+  
   # Additions compared to LND
   - exhaustruct
 
@@ -120,6 +121,7 @@ issues:
       - path: _test\.go
         linters:
           - forbidigo
+          - unparam
 
       # Allow fmt.Printf() in loopd
       - path: cmd/loopd/*

client.go

@@ -355,7 +355,7 @@ func (s *Client) resumeSwaps(ctx context.Context,
 		if pend.State().State.Type() != loopdb.StateTypePending {
 			continue
 		}
-		swap, err := resumeLoopOutSwap(ctx, swapCfg, pend)
+		swap, err := resumeLoopOutSwap(swapCfg, pend)
 		if err != nil {
 			log.Errorf("resuming loop out swap: %v", err)
 			continue

client_test.go

@@ -141,7 +141,6 @@ func TestLoopOutFailWrongAmount(t *testing.T) {
 			m.prepayInvoiceAmt += 10
 		}, ErrPrepayAmountTooHigh)
 	})
-
 }
 
 // TestLoopOutResume tests that swaps in various states are properly resumed

cmd/loop/loopin.go

@@ -94,7 +94,6 @@ func loopIn(ctx *cli.Context) error {
 		amtStr = ctx.String("amt")
 	case ctx.NArg() > 0:
 		amtStr = args[0]
-		args = args.Tail()
 	default:
 		// Show command help if no arguments and flags were provided.
 		return cli.ShowCommandHelp(ctx, "in")

executor.go

@@ -38,7 +38,7 @@ type executorConfig struct {
 
 // executor is responsible for executing swaps.
 //
-// TODO(roasbeef): rename to SubSwapper
+// TODO(roasbeef): rename to SubSwapper.
 type executor struct {
 	wg            sync.WaitGroup
 	newSwaps      chan genericSwap
@@ -134,9 +134,9 @@ func (s *executor) run(mainCtx context.Context,
 
 	swapDoneChan := make(chan int)
 	nextSwapID := 0
+
 	for {
 		select {
-
 		case newSwap := <-s.newSwaps:
 			queue := queue.NewConcurrentQueue(10)
 			queue.Start()

interface.go

@@ -363,7 +363,7 @@ type SwapInfo struct {
 	OutgoingChanSet loopdb.ChannelSet
 }
 
-// LastUpdate returns the last update time of the swap
+// LastUpdate returns the last update time of the swap.
 func (s *In) LastUpdate() time.Time {
 	return s.LastUpdateTime
 }

loopdb/loop.go

@@ -58,7 +58,7 @@ type SwapContract struct {
 	ProtocolVersion ProtocolVersion
 }
 
-// Loop contains fields shared between LoopIn and LoopOut
+// Loop contains fields shared between LoopIn and LoopOut.
 type Loop struct {
 	Hash   lntypes.Hash
 	Events []*LoopEvent

loopdb/meta.go

@@ -92,7 +92,6 @@ func syncVersions(db *bbolt.DB, chainParams *chaincfg.Params) error {
 		"db_version=%v", latestDBVersion, currentVersion)
 
 	switch {
-
 	// If the database reports a higher version that we are aware of, the
 	// user is probably trying to revert to a prior version of lnd. We fail
 	// here to prevent reversions and unintended corruption.

loopin.go

@@ -221,7 +221,7 @@ func newLoopInSwap(globalCtx context.Context, cfg *swapConfig,
 
 	// Validate the response parameters the prevent us continuing with a
 	// swap that is based on parameters outside our allowed range.
-	err = validateLoopInContract(cfg.lnd, currentHeight, request, swapResp)
+	err = validateLoopInContract(currentHeight, swapResp)
 	if err != nil {
 		return nil, err
 	}
@@ -387,11 +387,7 @@ func resumeLoopInSwap(_ context.Context, cfg *swapConfig,
 
 // validateLoopInContract validates the contract parameters against our
 // request.
-func validateLoopInContract(lnd *lndclient.LndServices,
-	height int32,
-	request *LoopInRequest,
-	response *newLoopInResponse) error {
-
+func validateLoopInContract(height int32, response *newLoopInResponse) error {
 	// Verify that we are not forced to publish an htlc that locks up our
 	// funds for too long in case the server doesn't follow through.
 	if response.expiry-height > MaxLoopInAcceptDelta {
@@ -640,7 +636,6 @@ func (s *loopInSwap) waitForHtlcConf(globalCtx context.Context) (
 	var conf *chainntnfs.TxConfirmation
 	for conf == nil {
 		select {
-
 		// P2WSH htlc confirmed.
 		case conf = <-confChanP2WSH:
 			s.htlc = s.htlcP2WSH
@@ -756,7 +751,6 @@ func (s *loopInSwap) publishOnChainHtlc(ctx context.Context) (bool, error) {
 	}
 
 	return true, nil
-
 }
 
 // getTxFee calculates our fee for a transaction that we have broadcast. We use
@@ -875,7 +869,6 @@ func (s *loopInSwap) waitForSwapComplete(ctx context.Context,
 				update.State)
 
 			switch update.State {
-
 			// Swap invoice was paid, so update server cost balance.
 			case channeldb.ContractSettled:
 				s.cost.Server -= update.AmtPaid

loopout.go

@@ -92,7 +92,7 @@ type executeConfig struct {
 	sweeper            *sweep.Sweeper
 	statusChan         chan<- SwapInfo
 	blockEpochChan     <-chan interface{}
-	timerFactory       func(d time.Duration) <-chan time.Time
+	timerFactory       func(time.Duration) <-chan time.Time
 	loopOutMaxParts    uint32
 	totalPaymentTimout time.Duration
 	maxPaymentRetries  int
@@ -144,7 +144,7 @@ func newLoopOutSwap(globalCtx context.Context, cfg *swapConfig,
 	}
 
 	err = validateLoopOutContract(
-		cfg.lnd, currentHeight, request, swapHash, swapResp,
+		cfg.lnd, request, swapHash, swapResp,
 	)
 	if err != nil {
 		return nil, err
@@ -246,8 +246,8 @@ func newLoopOutSwap(globalCtx context.Context, cfg *swapConfig,
 
 // resumeLoopOutSwap returns a swap object representing a pending swap that has
 // been restored from the database.
-func resumeLoopOutSwap(reqContext context.Context, cfg *swapConfig,
-	pend *loopdb.LoopOut) (*loopOutSwap, error) {
+func resumeLoopOutSwap(cfg *swapConfig, pend *loopdb.LoopOut,
+) (*loopOutSwap, error) {
 
 	hash := lntypes.Hash(sha256.Sum256(pend.Contract.Preimage[:]))
 
@@ -386,7 +386,6 @@ func (s *loopOutSwap) execute(mainCtx context.Context,
 // executeAndFinalize executes a swap and awaits the definitive outcome of the
 // offchain payments. When this method returns, the swap outcome is final.
 func (s *loopOutSwap) executeAndFinalize(globalCtx context.Context) error {
-
 	// Announce swap by sending out an initial update.
 	err := s.sendUpdate(globalCtx)
 	if err != nil {
@@ -996,7 +995,6 @@ func (s *loopOutSwap) waitForConfirmedHtlc(globalCtx context.Context) (
 		}
 
 		s.log.Infof("Swap script confirmed on chain")
-
 	} else {
 		s.log.Infof("Retrieving htlc onchain")
 		select {
@@ -1650,9 +1648,8 @@ func (s *loopOutSwap) sweep(ctx context.Context, htlcOutpoint wire.OutPoint,
 
 // validateLoopOutContract validates the contract parameters against our
 // request.
-func validateLoopOutContract(lnd *lndclient.LndServices,
-	height int32, request *OutRequest, swapHash lntypes.Hash,
-	response *newLoopOutResponse) error {
+func validateLoopOutContract(lnd *lndclient.LndServices, request *OutRequest,
+	swapHash lntypes.Hash, response *newLoopOutResponse) error {
 
 	// Check invoice amounts.
 	chainParams := lnd.ChainParams