refactor: unify the error handling methods that are different from the project style

Signed-off-by: LesCyber <andi4cing@gmail.com>

funding/manager.go

@@ -3,6 +3,7 @@ package funding
 import (
 	"bytes"
 	"encoding/binary"
+	"errors"
 	"fmt"
 	"io"
 	"sync"
@@ -1112,7 +1113,7 @@ func (f *Manager) advanceFundingState(channel *channeldb.OpenChannel,
 		channelState, shortChanID, err := f.getChannelOpeningState(
 			&channel.FundingOutpoint,
 		)
-		if err == channeldb.ErrChannelNotFound {
+		if errors.Is(err, channeldb.ErrChannelNotFound) {
 			// Channel not in fundingManager's opening database,
 			// meaning it was successfully announced to the
 			// network.
@@ -1326,7 +1327,7 @@ func (f *Manager) advancePendingChannelState(channel *channeldb.OpenChannel,
 	}
 
 	confChannel, err := f.waitForFundingWithTimeout(channel)
-	if err == ErrConfirmationTimeout {
+	if errors.Is(err, ErrConfirmationTimeout) {
 		return f.fundingTimeout(channel, pendingChanID)
 	} else if err != nil {
 		return fmt.Errorf("error waiting for funding "+

graph/db/graph.go

@@ -1076,7 +1076,7 @@ func (c *ChannelGraph) AddChannelEdge(edge *models.ChannelEdgeInfo,
 
 			// Silence ErrEdgeAlreadyExist so that the batch can
 			// succeed, but propagate the error via local state.
-			if err == ErrEdgeAlreadyExist {
+			if errors.Is(err, ErrEdgeAlreadyExist) {
 				alreadyExists = true
 				return nil
 			}
@@ -3493,7 +3493,7 @@ func (c *ChannelGraph) FetchChannelEdgesByID(chanID uint64) (
 		policy1 = nil
 		policy2 = nil
 	})
-	if err == ErrZombieEdge {
+	if errors.Is(err, ErrZombieEdge) {
 		return edgeInfo, nil, nil, err
 	}
 	if err != nil {

lnrpc/websocket_proxy.go

@@ -5,6 +5,7 @@ package lnrpc
 
 import (
 	"bufio"
+	"errors"
 	"io"
 	"net/http"
 	"net/textproto"
@@ -500,7 +501,7 @@ func IsClosedConnError(err error) bool {
 	if err == nil {
 		return false
 	}
-	if err == http.ErrServerClosed {
+	if errors.Is(err, http.ErrServerClosed) {
 		return true
 	}
 

peer/brontide.go

@@ -4001,7 +4001,7 @@ func (p *Brontide) handleCloseMsg(msg *closeMsg) {
 	chanCloser, err := p.fetchActiveChanCloser(msg.cid)
 	if err != nil {
 		// If the channel is not known to us, we'll simply ignore this message.
-		if err == ErrChannelNotFound {
+		if errors.Is(err, ErrChannelNotFound) {
 			return
 		}
 

rpcserver.go

@@ -1440,7 +1440,7 @@ func (r *rpcServer) SendCoins(ctx context.Context,
 		// If sending everything to this address would invalidate our
 		// reserved wallet balance, we create a new sweep tx, where
 		// we'll send the reserved value back to our wallet.
-		if err == lnwallet.ErrReservedValueInvalidated {
+		if errors.Is(err, lnwallet.ErrReservedValueInvalidated) {
 			sweepTxPkg.CancelSweepAttempt()
 
 			rpcsLog.Debugf("Reserved value %v not satisfied after "+
@@ -4348,7 +4348,7 @@ func (r *rpcServer) nurseryPopulateForceCloseResp(chanPoint *wire.OutPoint,
 	// didn't have any time-locked outputs, then the nursery may not know of
 	// the contract.
 	nurseryInfo, err := r.server.utxoNursery.NurseryReport(chanPoint)
-	if err == contractcourt.ErrContractNotFound {
+	if errors.Is(err, contractcourt.ErrContractNotFound) {
 		return nil
 	}
 	if err != nil {

server.go

@@ -5,6 +5,7 @@ import (
 	"context"
 	"crypto/rand"
 	"encoding/hex"
+	"errors"
 	"fmt"
 	"math/big"
 	prand "math/rand"
@@ -4906,7 +4907,7 @@ func (s *server) DisconnectPeer(pubKey *btcec.PublicKey) error {
 	// exit in an error as we can't disconnect from a peer that we're not
 	// currently connected to.
 	peer, err := s.findPeerByPubStr(pubStr)
-	if err == ErrPeerNotConnected {
+	if errors.Is(err, ErrPeerNotConnected) {
 		return fmt.Errorf("peer %x is not connected", pubBytes)
 	}