misc: fix error formatting in multiple files

autopilot/agent.go

@@ -648,7 +648,7 @@ func (a *Agent) openChans(availableFunds btcutil.Amount, numChans uint32,
 	// to open channels to.
 	scores, err = chooseN(numChans, scores)
 	if err != nil {
-		return fmt.Errorf("Unable to make weighted choice: %v",
+		return fmt.Errorf("unable to make weighted choice: %v",
 			err)
 	}
 

autopilot/combinedattach.go

@@ -130,7 +130,7 @@ func (c *WeightedCombAttachment) NodeScores(g ChannelGraph, chans []Channel,
 
 		// Sanity check the new score.
 		case score.Score < 0 || score.Score > 1.0:
-			return nil, fmt.Errorf("Invalid node score from "+
+			return nil, fmt.Errorf("invalid node score from "+
 				"combination: %v", score.Score)
 		}
 

breacharbiter.go

@@ -1358,8 +1358,8 @@ func (rs *retributionStore) Remove(chanPoint *wire.OutPoint) error {
 		// to remove a finalized retribution state that is not already
 		// stored in the db.
 		if retBucket == nil {
-			return errors.New("Unable to remove retribution " +
-				"because the retribution bucket doesn't exist.")
+			return errors.New("unable to remove retribution " +
+				"because the retribution bucket doesn't exist")
 		}
 
 		// Serialize the channel point we are intending to remove.

brontide/noise.go

@@ -492,7 +492,7 @@ func (b *Machine) RecvActOne(actOne [ActOneSize]byte) error {
 	// If the handshake version is unknown, then the handshake fails
 	// immediately.
 	if actOne[0] != HandshakeVersion {
-		return fmt.Errorf("Act One: invalid handshake version: %v, "+
+		return fmt.Errorf("act one: invalid handshake version: %v, "+
 			"only %v is valid, msg=%x", actOne[0], HandshakeVersion,
 			actOne[:])
 	}
@@ -564,7 +564,7 @@ func (b *Machine) RecvActTwo(actTwo [ActTwoSize]byte) error {
 	// If the handshake version is unknown, then the handshake fails
 	// immediately.
 	if actTwo[0] != HandshakeVersion {
-		return fmt.Errorf("Act Two: invalid handshake version: %v, "+
+		return fmt.Errorf("act two: invalid handshake version: %v, "+
 			"only %v is valid, msg=%x", actTwo[0], HandshakeVersion,
 			actTwo[:])
 	}
@@ -630,7 +630,7 @@ func (b *Machine) RecvActThree(actThree [ActThreeSize]byte) error {
 	// If the handshake version is unknown, then the handshake fails
 	// immediately.
 	if actThree[0] != HandshakeVersion {
-		return fmt.Errorf("Act Three: invalid handshake version: %v, "+
+		return fmt.Errorf("act three: invalid handshake version: %v, "+
 			"only %v is valid, msg=%x", actThree[0], HandshakeVersion,
 			actThree[:])
 	}

chainntnfs/txnotifier.go

@@ -1690,7 +1690,7 @@ func (n *TxNotifier) DisconnectTip(blockHeight uint32) error {
 	defer n.Unlock()
 
 	if blockHeight != n.currentHeight {
-		return fmt.Errorf("Received blocks out of order: "+
+		return fmt.Errorf("received blocks out of order: "+
 			"current height=%d, disconnected height=%d",
 			n.currentHeight, blockHeight)
 	}

chainregistry.go

@@ -201,7 +201,7 @@ func newChainControlFromConfig(cfg *config, chanDB *channeldb.DB,
 			defaultLitecoinStaticFeePerKW, 0,
 		)
 	default:
-		return nil, fmt.Errorf("Default routing policy for chain %v is "+
+		return nil, fmt.Errorf("default routing policy for chain %v is "+
 			"unknown", registeredChains.PrimaryChain())
 	}
 

channeldb/graph.go

@@ -3086,7 +3086,7 @@ func (c *ChannelGraph) IsPublicNode(pubKey [33]byte) (bool, error) {
 // genMultiSigP2WSH generates the p2wsh'd multisig script for 2 of 2 pubkeys.
 func genMultiSigP2WSH(aPub, bPub []byte) ([]byte, error) {
 	if len(aPub) != 33 || len(bPub) != 33 {
-		return nil, fmt.Errorf("Pubkey size error. Compressed " +
+		return nil, fmt.Errorf("pubkey size error. Compressed " +
 			"pubkeys only")
 	}
 
@@ -3833,7 +3833,7 @@ func putChanEdgePolicyUnknown(edges kvdb.RwBucket, channelID uint64,
 	byteOrder.PutUint64(edgeKey[33:], channelID)
 
 	if edges.Get(edgeKey[:]) != nil {
-		return fmt.Errorf("Cannot write unknown policy for channel %v "+
+		return fmt.Errorf("cannot write unknown policy for channel %v "+
 			" when there is already a policy present", channelID)
 	}
 

config.go

@@ -1150,7 +1150,7 @@ func loadConfig() (*config, error) {
 	// the wallet.
 	_, err = parseHexColor(cfg.Color)
 	if err != nil {
-		return nil, fmt.Errorf("Unable to parse node color: %v", err)
+		return nil, fmt.Errorf("unable to parse node color: %v", err)
 	}
 
 	// Warn about missing config file only after all other configuration is

fundingmanager.go

@@ -1929,7 +1929,7 @@ func (f *fundingManager) handleFundingSigned(fmsg *fundingSignedMsg) {
 	delete(f.signedReservations, fmsg.msg.ChanID)
 	f.resMtx.Unlock()
 	if !ok {
-		err := fmt.Errorf("Unable to find signed reservation for "+
+		err := fmt.Errorf("unable to find signed reservation for "+
 			"chan_id=%x", fmsg.msg.ChanID)
 		fndgLog.Warnf(err.Error())
 		f.failFundingFlow(fmsg.peer, fmsg.msg.ChanID, err)
@@ -2562,7 +2562,7 @@ func (f *fundingManager) annAfterSixConfs(completeChan *channeldb.OpenChannel,
 			completeChan.FundingBroadcastHeight,
 		)
 		if err != nil {
-			return fmt.Errorf("Unable to register for "+
+			return fmt.Errorf("unable to register for "+
 				"confirmation of ChannelPoint(%v): %v",
 				completeChan.FundingOutpoint, err)
 		}
@@ -3217,7 +3217,7 @@ func (f *fundingManager) handleInitFundingMsg(msg *initFundingMsg) {
 		UpfrontShutdownScript: shutdown,
 	}
 	if err := msg.peer.SendMessage(true, &fundingOpen); err != nil {
-		e := fmt.Errorf("Unable to send funding request message: %v",
+		e := fmt.Errorf("unable to send funding request message: %v",
 			err)
 		fndgLog.Errorf(e.Error())
 
@@ -3501,7 +3501,7 @@ func (f *fundingManager) deleteChannelOpeningState(chanPoint *wire.OutPoint) err
 	return kvdb.Update(f.cfg.Wallet.Cfg.Database, func(tx kvdb.RwTx) error {
 		bucket := tx.ReadWriteBucket(channelOpeningStateBucket)
 		if bucket == nil {
-			return fmt.Errorf("Bucket not found")
+			return fmt.Errorf("bucket not found")
 		}
 
 		var outpointBytes bytes.Buffer

fundingmanager_test.go

@@ -2839,7 +2839,7 @@ func TestFundingManagerRejectPush(t *testing.T) {
 
 	// Assert Bob responded with an ErrNonZeroPushAmount error.
 	err := assertFundingMsgSent(t, bob.msgChan, "Error").(*lnwire.Error)
-	if !strings.Contains(err.Error(), "Non-zero push amounts are disabled") {
+	if !strings.Contains(err.Error(), "non-zero push amounts are disabled") {
 		t.Fatalf("expected ErrNonZeroPushAmount error, got \"%v\"",
 			err.Error())
 	}

htlcswitch/decayedlog.go

@@ -93,7 +93,7 @@ func (d *DecayedLog) Start() error {
 		kvdb.BoltBackendName, d.dbPath, true,
 	)
 	if err != nil {
-		return fmt.Errorf("Could not open boltdb: %v", err)
+		return fmt.Errorf("could not open boltdb: %v", err)
 	}
 
 	// Initialize the primary buckets used by the decayed log.
@@ -105,7 +105,7 @@ func (d *DecayedLog) Start() error {
 	if d.notifier != nil {
 		epochClient, err := d.notifier.RegisterBlockEpochNtfn(nil)
 		if err != nil {
-			return fmt.Errorf("Unable to register for epoch "+
+			return fmt.Errorf("unable to register for epoch "+
 				"notifications: %v", err)
 		}
 

htlcswitch/link.go

@@ -634,7 +634,7 @@ func (l *channelLink) syncChanStates() error {
 	}
 
 	if err := l.cfg.Peer.SendMessage(true, localChanSyncMsg); err != nil {
-		return fmt.Errorf("Unable to send chan sync message for "+
+		return fmt.Errorf("unable to send chan sync message for "+
 			"ChannelPoint(%v): %v", l.channel.ChannelPoint(), err)
 	}
 

htlcswitch/switch.go

@@ -421,7 +421,7 @@ func (s *Switch) GetPaymentResult(paymentID uint64, paymentHash lntypes.Hash,
 			deobfuscator, n, paymentID, paymentHash,
 		)
 		if err != nil {
-			e := fmt.Errorf("Unable to extract result: %v", err)
+			e := fmt.Errorf("unable to extract result: %v", err)
 			log.Error(e)
 			resultChan <- &PaymentResult{
 				Error: e,
@@ -770,7 +770,7 @@ func (s *Switch) routeAsync(packet *htlcPacket, errChan chan error,
 	case <-linkQuit:
 		return ErrLinkShuttingDown
 	case <-s.quit:
-		return errors.New("Htlc Switch was stopped")
+		return errors.New("htlc switch was stopped")
 	}
 }
 
@@ -962,7 +962,7 @@ func (s *Switch) extractResult(deobfuscator ErrorDecrypter, n *networkResult,
 		}, nil
 
 	default:
-		return nil, fmt.Errorf("Received unknown response type: %T",
+		return nil, fmt.Errorf("received unknown response type: %T",
 			htlc)
 	}
 }

input/script_utils.go

@@ -49,7 +49,7 @@ func WitnessScriptHash(witnessScript []byte) ([]byte, error) {
 // pubkeys.
 func GenMultiSigScript(aPub, bPub []byte) ([]byte, error) {
 	if len(aPub) != 33 || len(bPub) != 33 {
-		return nil, fmt.Errorf("Pubkey size error. Compressed pubkeys only")
+		return nil, fmt.Errorf("pubkey size error: compressed pubkeys only")
 	}
 
 	// Swap to sort pubkeys if needed. Keys are sorted in lexicographical

input/test_utils.go

@@ -64,7 +64,7 @@ func (m *MockSigner) SignOutputRaw(tx *wire.MsgTx,
 	hash160 := btcutil.Hash160(pubkey.SerializeCompressed())
 	privKey := m.findKey(hash160, signDesc.SingleTweak, signDesc.DoubleTweak)
 	if privKey == nil {
-		return nil, fmt.Errorf("Mock signer does not have key")
+		return nil, fmt.Errorf("mock signer does not have key")
 	}
 
 	sig, err := txscript.RawTxInWitnessSignature(tx, signDesc.SigHashes,
@@ -93,7 +93,7 @@ func (m *MockSigner) ComputeInputScript(tx *wire.MsgTx, signDesc *SignDescriptor
 		privKey := m.findKey(addresses[0].ScriptAddress(), signDesc.SingleTweak,
 			signDesc.DoubleTweak)
 		if privKey == nil {
-			return nil, fmt.Errorf("Mock signer does not have key for "+
+			return nil, fmt.Errorf("mock signer does not have key for "+
 				"address %v", addresses[0])
 		}
 
@@ -111,7 +111,7 @@ func (m *MockSigner) ComputeInputScript(tx *wire.MsgTx, signDesc *SignDescriptor
 		privKey := m.findKey(addresses[0].ScriptAddress(), signDesc.SingleTweak,
 			signDesc.DoubleTweak)
 		if privKey == nil {
-			return nil, fmt.Errorf("Mock signer does not have key for "+
+			return nil, fmt.Errorf("mock signer does not have key for "+
 				"address %v", addresses[0])
 		}
 
@@ -125,7 +125,7 @@ func (m *MockSigner) ComputeInputScript(tx *wire.MsgTx, signDesc *SignDescriptor
 		return &Script{Witness: witnessScript}, nil
 
 	default:
-		return nil, fmt.Errorf("Unexpected script type: %v", scriptType)
+		return nil, fmt.Errorf("unexpected script type: %v", scriptType)
 	}
 }
 

lnd.go

@@ -209,7 +209,7 @@ func Main(lisCfg ListenerCfg) error {
 	if cfg.CPUProfile != "" {
 		f, err := os.Create(cfg.CPUProfile)
 		if err != nil {
-			err := fmt.Errorf("Unable to create CPU profile: %v",
+			err := fmt.Errorf("unable to create CPU profile: %v",
 				err)
 			ltndLog.Error(err)
 			return err
@@ -237,7 +237,7 @@ func Main(lisCfg ListenerCfg) error {
 		channeldb.OptionSetSyncFreelist(cfg.SyncFreelist),
 	)
 	if err != nil {
-		err := fmt.Errorf("Unable to open channeldb: %v", err)
+		err := fmt.Errorf("unable to open channeldb: %v", err)
 		ltndLog.Error(err)
 		return err
 	}
@@ -256,7 +256,7 @@ func Main(lisCfg ListenerCfg) error {
 		cfg.TLSExtraDomains, cfg.RPCListeners,
 	)
 	if err != nil {
-		err := fmt.Errorf("Unable to load TLS credentials: %v", err)
+		err := fmt.Errorf("unable to load TLS credentials: %v", err)
 		ltndLog.Error(err)
 		return err
 	}
@@ -289,7 +289,7 @@ func Main(lisCfg ListenerCfg) error {
 			mainChain.ChainDir,
 		)
 		if err != nil {
-			err := fmt.Errorf("Unable to initialize neutrino "+
+			err := fmt.Errorf("unable to initialize neutrino "+
 				"backend: %v", err)
 			ltndLog.Error(err)
 			return err
@@ -364,7 +364,7 @@ func Main(lisCfg ListenerCfg) error {
 			restProxyDest, tlsCfg, walletUnlockerListeners,
 		)
 		if err != nil {
-			err := fmt.Errorf("Unable to set up wallet password "+
+			err := fmt.Errorf("unable to set up wallet password "+
 				"listeners: %v", err)
 			ltndLog.Error(err)
 			return err
@@ -388,7 +388,7 @@ func Main(lisCfg ListenerCfg) error {
 			networkDir, macaroons.IPLockChecker,
 		)
 		if err != nil {
-			err := fmt.Errorf("Unable to set up macaroon "+
+			err := fmt.Errorf("unable to set up macaroon "+
 				"authentication: %v", err)
 			ltndLog.Error(err)
 			return err
@@ -398,7 +398,7 @@ func Main(lisCfg ListenerCfg) error {
 		// Try to unlock the macaroon store with the private password.
 		err = macaroonService.CreateUnlock(&privateWalletPw)
 		if err != nil {
-			err := fmt.Errorf("Unable to unlock macaroons: %v", err)
+			err := fmt.Errorf("unable to unlock macaroons: %v", err)
 			ltndLog.Error(err)
 			return err
 		}
@@ -412,7 +412,7 @@ func Main(lisCfg ListenerCfg) error {
 				cfg.ReadMacPath, cfg.InvoiceMacPath,
 			)
 			if err != nil {
-				err := fmt.Errorf("Unable to create macaroons "+
+				err := fmt.Errorf("unable to create macaroons "+
 					"%v", err)
 				ltndLog.Error(err)
 				return err
@@ -429,7 +429,7 @@ func Main(lisCfg ListenerCfg) error {
 		walletInitParams.Wallet, neutrinoCS,
 	)
 	if err != nil {
-		err := fmt.Errorf("Unable to create chain control: %v", err)
+		err := fmt.Errorf("unable to create chain control: %v", err)
 		ltndLog.Error(err)
 		return err
 	}
@@ -448,7 +448,7 @@ func Main(lisCfg ListenerCfg) error {
 		},
 	})
 	if err != nil {
-		err := fmt.Errorf("Unable to derive node private key: %v", err)
+		err := fmt.Errorf("unable to derive node private key: %v", err)
 		ltndLog.Error(err)
 		return err
 	}
@@ -467,7 +467,7 @@ func Main(lisCfg ListenerCfg) error {
 		var err error
 		towerClientDB, err = wtdb.OpenClientDB(graphDir)
 		if err != nil {
-			err := fmt.Errorf("Unable to open watchtower client "+
+			err := fmt.Errorf("unable to open watchtower client "+
 				"database: %v", err)
 			ltndLog.Error(err)
 			return err
@@ -508,7 +508,7 @@ func Main(lisCfg ListenerCfg) error {
 
 		towerDB, err := wtdb.OpenTowerDB(towerDBDir)
 		if err != nil {
-			err := fmt.Errorf("Unable to open watchtower "+
+			err := fmt.Errorf("unable to open watchtower "+
 				"database: %v", err)
 			ltndLog.Error(err)
 			return err
@@ -524,7 +524,7 @@ func Main(lisCfg ListenerCfg) error {
 			},
 		)
 		if err != nil {
-			err := fmt.Errorf("Unable to derive watchtower "+
+			err := fmt.Errorf("unable to derive watchtower "+
 				"private key: %v", err)
 			ltndLog.Error(err)
 			return err
@@ -561,7 +561,7 @@ func Main(lisCfg ListenerCfg) error {
 
 		wtConfig, err := cfg.Watchtower.Apply(wtCfg, lncfg.NormalizeAddresses)
 		if err != nil {
-			err := fmt.Errorf("Unable to configure watchtower: %v",
+			err := fmt.Errorf("unable to configure watchtower: %v",
 				err)
 			ltndLog.Error(err)
 			return err
@@ -569,7 +569,7 @@ func Main(lisCfg ListenerCfg) error {
 
 		tower, err = watchtower.New(wtConfig)
 		if err != nil {
-			err := fmt.Errorf("Unable to create watchtower: %v", err)
+			err := fmt.Errorf("unable to create watchtower: %v", err)
 			ltndLog.Error(err)
 			return err
 		}
@@ -586,7 +586,7 @@ func Main(lisCfg ListenerCfg) error {
 		torController,
 	)
 	if err != nil {
-		err := fmt.Errorf("Unable to create server: %v", err)
+		err := fmt.Errorf("unable to create server: %v", err)
 		ltndLog.Error(err)
 		return err
 	}
@@ -596,19 +596,19 @@ func Main(lisCfg ListenerCfg) error {
 	// it at will.
 	atplCfg, err := initAutoPilot(server, cfg.Autopilot, mainChain)
 	if err != nil {
-		err := fmt.Errorf("Unable to initialize autopilot: %v", err)
+		err := fmt.Errorf("unable to initialize autopilot: %v", err)
 		ltndLog.Error(err)
 		return err
 	}
 
 	atplManager, err := autopilot.NewManager(atplCfg)
 	if err != nil {
-		err := fmt.Errorf("Unable to create autopilot manager: %v", err)
+		err := fmt.Errorf("unable to create autopilot manager: %v", err)
 		ltndLog.Error(err)
 		return err
 	}
 	if err := atplManager.Start(); err != nil {
-		err := fmt.Errorf("Unable to start autopilot manager: %v", err)
+		err := fmt.Errorf("unable to start autopilot manager: %v", err)
 		ltndLog.Error(err)
 		return err
 	}
@@ -636,12 +636,12 @@ func Main(lisCfg ListenerCfg) error {
 		tower, tlsCfg, rpcListeners, chainedAcceptor,
 	)
 	if err != nil {
-		err := fmt.Errorf("Unable to create RPC server: %v", err)
+		err := fmt.Errorf("unable to create RPC server: %v", err)
 		ltndLog.Error(err)
 		return err
 	}
 	if err := rpcServer.Start(); err != nil {
-		err := fmt.Errorf("Unable to start RPC server: %v", err)
+		err := fmt.Errorf("unable to start RPC server: %v", err)
 		ltndLog.Error(err)
 		return err
 	}
@@ -656,7 +656,7 @@ func Main(lisCfg ListenerCfg) error {
 
 		_, bestHeight, err := activeChainControl.chainIO.GetBestBlock()
 		if err != nil {
-			err := fmt.Errorf("Unable to determine chain tip: %v",
+			err := fmt.Errorf("unable to determine chain tip: %v",
 				err)
 			ltndLog.Error(err)
 			return err
@@ -672,7 +672,7 @@ func Main(lisCfg ListenerCfg) error {
 
 			synced, _, err := activeChainControl.wallet.IsSynced()
 			if err != nil {
-				err := fmt.Errorf("Unable to determine if "+
+				err := fmt.Errorf("unable to determine if "+
 					"wallet is synced: %v", err)
 				ltndLog.Error(err)
 				return err
@@ -687,7 +687,7 @@ func Main(lisCfg ListenerCfg) error {
 
 		_, bestHeight, err = activeChainControl.chainIO.GetBestBlock()
 		if err != nil {
-			err := fmt.Errorf("Unable to determine chain tip: %v",
+			err := fmt.Errorf("unable to determine chain tip: %v",
 				err)
 			ltndLog.Error(err)
 			return err
@@ -700,7 +700,7 @@ func Main(lisCfg ListenerCfg) error {
 	// With all the relevant chains initialized, we can finally start the
 	// server itself.
 	if err := server.Start(); err != nil {
-		err := fmt.Errorf("Unable to start server: %v", err)
+		err := fmt.Errorf("unable to start server: %v", err)
 		ltndLog.Error(err)
 		return err
 	}
@@ -711,7 +711,7 @@ func Main(lisCfg ListenerCfg) error {
 	// stopped together with the autopilot service.
 	if cfg.Autopilot.Active {
 		if err := atplManager.StartAgent(); err != nil {
-			err := fmt.Errorf("Unable to start autopilot agent: %v",
+			err := fmt.Errorf("unable to start autopilot agent: %v",
 				err)
 			ltndLog.Error(err)
 			return err
@@ -720,7 +720,7 @@ func Main(lisCfg ListenerCfg) error {
 
 	if cfg.Watchtower.Active {
 		if err := tower.Start(); err != nil {
-			err := fmt.Errorf("Unable to start watchtower: %v", err)
+			err := fmt.Errorf("unable to start watchtower: %v", err)
 			ltndLog.Error(err)
 			return err
 		}

lntest/harness.go

@@ -685,7 +685,7 @@ func (n *NetworkHarness) SaveProfilesPages() {
 
 	for _, node := range n.activeNodes {
 		if err := saveProfilesPage(node); err != nil {
-			fmt.Println(err)
+			fmt.Printf("Error: %v\n", err)
 		}
 	}
 }
@@ -699,16 +699,16 @@ func saveProfilesPage(node *HarnessNode) error {
 		),
 	)
 	if err != nil {
-		return fmt.Errorf("Failed to get profile page "+
-			"(node_id=%d, name=%s): %v\n",
+		return fmt.Errorf("failed to get profile page "+
+			"(node_id=%d, name=%s): %v",
 			node.NodeID, node.Cfg.Name, err)
 	}
 	defer resp.Body.Close()
 
 	body, err := ioutil.ReadAll(resp.Body)
 	if err != nil {
-		return fmt.Errorf("Failed to read profile page "+
-			"(node_id=%d, name=%s): %v\n",
+		return fmt.Errorf("failed to read profile page "+
+			"(node_id=%d, name=%s): %v",
 			node.NodeID, node.Cfg.Name, err)
 	}
 
@@ -719,16 +719,16 @@ func saveProfilesPage(node *HarnessNode) error {
 
 	logFile, err := os.Create(fileName)
 	if err != nil {
-		return fmt.Errorf("Failed to create file for profile page "+
-			"(node_id=%d, name=%s): %v\n",
+		return fmt.Errorf("failed to create file for profile page "+
+			"(node_id=%d, name=%s): %v",
 			node.NodeID, node.Cfg.Name, err)
 	}
 	defer logFile.Close()
 
 	_, err = logFile.Write(body)
 	if err != nil {
-		return fmt.Errorf("Failed to save profile page "+
-			"(node_id=%d, name=%s): %v\n",
+		return fmt.Errorf("failed to save profile page "+
+			"(node_id=%d, name=%s): %v",
 			node.NodeID, node.Cfg.Name, err)
 	}
 	return nil
@@ -872,10 +872,10 @@ func (n *NetworkHarness) OpenChannel(ctx context.Context,
 	// prevents any funding workflows from being kicked off if the chain
 	// isn't yet synced.
 	if err := srcNode.WaitForBlockchainSync(ctx); err != nil {
-		return nil, fmt.Errorf("Unable to sync srcNode chain: %v", err)
+		return nil, fmt.Errorf("enable to sync srcNode chain: %v", err)
 	}
 	if err := destNode.WaitForBlockchainSync(ctx); err != nil {
-		return nil, fmt.Errorf("Unable to sync destNode chain: %v", err)
+		return nil, fmt.Errorf("unable to sync destNode chain: %v", err)
 	}
 
 	minConfs := int32(1)
@@ -941,10 +941,10 @@ func (n *NetworkHarness) OpenPendingChannel(ctx context.Context,
 
 	// Wait until srcNode and destNode have blockchain synced
 	if err := srcNode.WaitForBlockchainSync(ctx); err != nil {
-		return nil, fmt.Errorf("Unable to sync srcNode chain: %v", err)
+		return nil, fmt.Errorf("unable to sync srcNode chain: %v", err)
 	}
 	if err := destNode.WaitForBlockchainSync(ctx); err != nil {
-		return nil, fmt.Errorf("Unable to sync destNode chain: %v", err)
+		return nil, fmt.Errorf("unable to sync destNode chain: %v", err)
 	}
 
 	openReq := &lnrpc.OpenChannelRequest{

lntest/node.go

@@ -1122,7 +1122,7 @@ func (hn *HarnessNode) WaitForBlockchainSync(ctx context.Context) error {
 	case err := <-errChan:
 		return err
 	case <-ctx.Done():
-		return fmt.Errorf("Timeout while waiting for blockchain sync")
+		return fmt.Errorf("timeout while waiting for blockchain sync")
 	}
 }
 

lnwallet/channel.go

@@ -3920,7 +3920,7 @@ func genHtlcSigValidationJobs(localCommitmentView *commitment,
 			// Make sure there are more signatures left.
 			if i >= len(htlcSigs) {
 				return nil, fmt.Errorf("not enough HTLC " +
-					"signatures.")
+					"signatures")
 			}
 
 			// With the sighash generated, we'll also store the
@@ -3974,7 +3974,7 @@ func genHtlcSigValidationJobs(localCommitmentView *commitment,
 			// Make sure there are more signatures left.
 			if i >= len(htlcSigs) {
 				return nil, fmt.Errorf("not enough HTLC " +
-					"signatures.")
+					"signatures")
 			}
 
 			// With the sighash generated, we'll also store the

lnwallet/errors.go

@@ -34,7 +34,7 @@ func ErrZeroCapacity() ReservationError {
 func ErrChainMismatch(knownChain,
 	unknownChain *chainhash.Hash) ReservationError {
 	return ReservationError{
-		fmt.Errorf("Unknown chain=%v. Supported chain=%v",
+		fmt.Errorf("unknown chain=%v, supported chain=%v",
 			unknownChain, knownChain),
 	}
 }
@@ -44,7 +44,7 @@ func ErrChainMismatch(knownChain,
 func ErrFunderBalanceDust(commitFee, funderBalance,
 	minBalance int64) ReservationError {
 	return ReservationError{
-		fmt.Errorf("Funder balance too small (%v) with fee=%v sat, "+
+		fmt.Errorf("funder balance too small (%v) with fee=%v sat, "+
 			"minimum=%v sat required", funderBalance,
 			commitFee, minBalance),
 	}
@@ -73,7 +73,7 @@ func ErrChanReserveTooSmall(reserve, dustLimit btcutil.Amount) ReservationError
 func ErrChanReserveTooLarge(reserve,
 	maxReserve btcutil.Amount) ReservationError {
 	return ReservationError{
-		fmt.Errorf("Channel reserve is too large: %v sat, max "+
+		fmt.Errorf("channel reserve is too large: %v sat, max "+
 			"is %v sat", int64(reserve), int64(maxReserve)),
 	}
 }
@@ -82,7 +82,7 @@ func ErrChanReserveTooLarge(reserve,
 // FundingOpen request for a channel with non-zero push amount while
 // they have 'rejectpush' enabled.
 func ErrNonZeroPushAmount() ReservationError {
-	return ReservationError{errors.New("Non-zero push amounts are disabled")}
+	return ReservationError{errors.New("non-zero push amounts are disabled")}
 }
 
 // ErrMinHtlcTooLarge returns an error indicating that the MinHTLC value the
@@ -90,7 +90,7 @@ func ErrNonZeroPushAmount() ReservationError {
 func ErrMinHtlcTooLarge(minHtlc,
 	maxMinHtlc lnwire.MilliSatoshi) ReservationError {
 	return ReservationError{
-		fmt.Errorf("Minimum HTLC value is too large: %v, max is %v",
+		fmt.Errorf("minimum HTLC value is too large: %v, max is %v",
 			minHtlc, maxMinHtlc),
 	}
 }

lnwallet/interface.go

@@ -43,7 +43,7 @@ var (
 	// ErrDoubleSpend is returned from PublishTransaction in case the
 	// tx being published is spending an output spent by a conflicting
 	// transaction.
-	ErrDoubleSpend = errors.New("Transaction rejected: output already spent")
+	ErrDoubleSpend = errors.New("transaction rejected: output already spent")
 
 	// ErrNotMine is an error denoting that a WalletController instance is
 	// unable to spend a specified output.

lnwallet/interface_test.go

@@ -753,7 +753,7 @@ func testReservationInitiatorBalanceBelowDustCancel(miner *rpctest.Harness,
 		t.Fatalf("initialization should have failed due to " +
 			"insufficient local amount")
 
-	case !strings.Contains(err.Error(), "Funder balance too small"):
+	case !strings.Contains(err.Error(), "funder balance too small"):
 		t.Fatalf("incorrect error: %v", err)
 	}
 }

lnwire/lnwire.go

@@ -419,7 +419,7 @@ func WriteElement(w io.Writer, element interface{}) error {
 			return err
 		}
 	default:
-		return fmt.Errorf("Unknown type in WriteElement: %T", e)
+		return fmt.Errorf("unknown type in WriteElement: %T", e)
 	}
 
 	return nil
@@ -818,14 +818,14 @@ func ReadElement(r io.Reader, element interface{}) error {
 
 		var addrBytes [deliveryAddressMaxSize]byte
 		if length > deliveryAddressMaxSize {
-			return fmt.Errorf("Cannot read %d bytes into addrBytes", length)
+			return fmt.Errorf("cannot read %d bytes into addrBytes", length)
 		}
 		if _, err = io.ReadFull(r, addrBytes[:length]); err != nil {
 			return err
 		}
 		*e = addrBytes[:length]
 	default:
-		return fmt.Errorf("Unknown type in ReadElement: %T", e)
+		return fmt.Errorf("unknown type in ReadElement: %T", e)
 	}
 
 	return nil

peer.go

@@ -1115,7 +1115,7 @@ func (p *peer) readHandler() {
 	// We'll stop the timer after a new messages is received, and also
 	// reset it after we process the next message.
 	idleTimer := time.AfterFunc(idleTimeout, func() {
-		err := fmt.Errorf("Peer %s no answer for %s -- disconnecting",
+		err := fmt.Errorf("peer %s no answer for %s -- disconnecting",
 			p, idleTimeout)
 		p.Disconnect(err)
 	})
@@ -1657,7 +1657,7 @@ func (p *peer) writeHandler() {
 	// We'll stop the timer after a new messages is sent, and also reset it
 	// after we process the next message.
 	idleTimer := time.AfterFunc(idleTimeout, func() {
-		err := fmt.Errorf("Peer %s no write for %s -- disconnecting",
+		err := fmt.Errorf("peer %s no write for %s -- disconnecting",
 			p, idleTimeout)
 		p.Disconnect(err)
 	})
@@ -2724,7 +2724,7 @@ func (p *peer) resendChanSyncMsg(cid lnwire.ChannelID) error {
 		"peer %v", cid, p)
 
 	if err := p.SendMessage(true, c.LastChanSyncMsg); err != nil {
-		return fmt.Errorf("Failed resending channel sync "+
+		return fmt.Errorf("failed resending channel sync "+
 			"message to peer %v: %v", p, err)
 	}
 

pilot.go

@@ -39,7 +39,7 @@ func validateAtplCfg(cfg *autoPilotConfig) ([]*autopilot.WeightedHeuristic,
 		a, ok := autopilot.AvailableHeuristics[name]
 		if !ok {
 			// No heuristic matching this config option was found.
-			return nil, fmt.Errorf("Heuristic %v not available. %v",
+			return nil, fmt.Errorf("heuristic %v not available. %v",
 				name, availStr)
 		}
 
@@ -58,11 +58,11 @@ func validateAtplCfg(cfg *autoPilotConfig) ([]*autopilot.WeightedHeuristic,
 
 	// Check found heuristics. We must have at least one to operate.
 	if len(heuristics) == 0 {
-		return nil, fmt.Errorf("No active heuristics. %v", availStr)
+		return nil, fmt.Errorf("no active heuristics: %v", availStr)
 	}
 
 	if sum != 1.0 {
-		return nil, fmt.Errorf("Heuristic weights must sum to 1.0")
+		return nil, fmt.Errorf("heuristic weights must sum to 1.0")
 	}
 	return heuristics, nil
 }

routing/notifications.go

@@ -386,7 +386,7 @@ func addToTopologyChange(graph *channeldb.ChannelGraph, update *TopologyChange,
 		return nil
 
 	default:
-		return fmt.Errorf("Unable to add to topology change, "+
+		return fmt.Errorf("unable to add to topology change, "+
 			"unknown message type %T", msg)
 	}
 }

routing/router.go

@@ -2197,7 +2197,7 @@ func (r *ChannelRouter) ForAllOutgoingChannels(cb func(*channeldb.ChannelEdgeInf
 		e, _ *channeldb.ChannelEdgePolicy) error {
 
 		if e == nil {
-			return fmt.Errorf("Channel from self node has no policy")
+			return fmt.Errorf("channel from self node has no policy")
 		}
 
 		return cb(c, e)

server.go

@@ -547,7 +547,7 @@ func newServer(listenAddrs []net.Addr, chanDB *channeldb.DB,
 
 			pmp, err := nat.DiscoverPMP(discoveryTimeout)
 			if err != nil {
-				err := fmt.Errorf("Unable to discover a "+
+				err := fmt.Errorf("unable to discover a "+
 					"NAT-PMP enabled device on the local "+
 					"network: %v", err)
 				srvrLog.Error(err)
@@ -1995,7 +1995,7 @@ func (s *server) createNewHiddenService() error {
 		},
 	)
 	if err != nil {
-		return fmt.Errorf("Unable to generate new node "+
+		return fmt.Errorf("unable to generate new node "+
 			"announcement: %v", err)
 	}