Fix multiple anti-patterns from DeepSource analysis (#6951)

* Merge variable declaration and assignment
* Use result of type assertion to simplify cases
* Replace call to bytes.Compare with bytes.Equal
* Drop unnecessary use of the blank identifier
* Replace x.Sub(time.Now()) with time.Until(x)
* Function literal can be simplified
* Use a single append to concatenate two slices
* Replace time.Now().Sub(x) with time.Since(x)
* Omit comparison with boolean constant
* Omit redundant nil check on slices
* Nested if can be replaced with else-if
* Function call can be replaced with helper function
* Omit redundant control flow
* Use plain channel send or receive
* Simplify returning boolean expression
* Merge branch 'origin-master' into fix-antipatterns
* Merge branch 'master' into fix-antipatterns

Author: rkapka

beacon-chain/blockchain/process_block.go

@@ -372,10 +372,8 @@ func (s *Service) savePostStateInfo(ctx context.Context, r [32]byte, b *ethpb.Si
 	defer span.End()
 	if initSync {
 		s.saveInitSyncBlock(r, b)
-	} else {
-		if err := s.beaconDB.SaveBlock(ctx, b); err != nil {
-			return errors.Wrapf(err, "could not save block from slot %d", b.Block.Slot)
-		}
+	} else if err := s.beaconDB.SaveBlock(ctx, b); err != nil {
+		return errors.Wrapf(err, "could not save block from slot %d", b.Block.Slot)
 	}
 	if err := s.stateGen.SaveState(ctx, r, state); err != nil {
 		return errors.Wrap(err, "could not save state")

beacon-chain/core/blocks/deposit.go

@@ -179,10 +179,8 @@ func ProcessDeposit(beaconState *stateTrie.BeaconState, deposit *ethpb.Deposit,
 		if err := beaconState.AppendBalance(amount); err != nil {
 			return nil, err
 		}
-	} else {
-		if err := helpers.IncreaseBalance(beaconState, index, amount); err != nil {
-			return nil, err
-		}
+	} else if err := helpers.IncreaseBalance(beaconState, index, amount); err != nil {
+		return nil, err
 	}
 
 	return beaconState, nil

beacon-chain/core/helpers/signing_root.go

@@ -49,11 +49,11 @@ func ComputeDomainAndSign(state *state.BeaconState, epoch uint64, obj interface{
 //    ))
 func ComputeSigningRoot(object interface{}, domain []byte) ([32]byte, error) {
 	return signingData(func() ([32]byte, error) {
-		switch object.(type) {
+		switch t := object.(type) {
 		case *ethpb.BeaconBlock:
-			return stateutil.BlockRoot(object.(*ethpb.BeaconBlock))
+			return stateutil.BlockRoot(t)
 		case *ethpb.AttestationData:
-			return stateutil.AttestationDataRoot(object.(*ethpb.AttestationData))
+			return stateutil.AttestationDataRoot(t)
 		default:
 			// utilise generic ssz library
 			return ssz.HashTreeRoot(object)

beacon-chain/db/kv/backup.go

@@ -54,9 +54,7 @@ func (kv *Store) Backup(ctx context.Context) error {
 				if err != nil {
 					return err
 				}
-				return b.ForEach(func(k []byte, v []byte) error {
-					return b2.Put(k, v)
-				})
+				return b.ForEach(b2.Put)
 			})
 		})
 	})

beacon-chain/gateway/gateway.go

@@ -87,8 +87,6 @@ func (g *Gateway) Start() {
 			return
 		}
 	}()
-
-	return
 }
 
 // Status of grpc gateway. Returns an error if this service is unhealthy.

beacon-chain/node/node.go

@@ -319,12 +319,10 @@ func (b *BeaconNode) startDB(cliCtx *cli.Context) error {
 		if err != nil {
 			return errors.Wrap(err, "could not create new database")
 		}
-	} else {
 		// Only check if historical states were deleted and needed to recompute when
 		// user doesn't want to skip.
-		if err := d.HistoricalStatesDeleted(b.ctx); err != nil {
-			return err
-		}
+	} else if err := d.HistoricalStatesDeleted(b.ctx); err != nil {
+		return err
 	}
 
 	if err := d.RunMigrations(b.ctx); err != nil {

beacon-chain/operations/attestations/prune_expired.go

@@ -62,8 +62,5 @@ func (s *Service) expired(slot uint64) bool {
 	expirationSlot := slot + params.BeaconConfig().SlotsPerEpoch
 	expirationTime := s.genesisTime + expirationSlot*params.BeaconConfig().SecondsPerSlot
 	currentTime := uint64(roughtime.Now().Unix())
-	if currentTime >= expirationTime {
-		return true
-	}
-	return false
+	return currentTime >= expirationTime
 }

beacon-chain/p2p/service.go

@@ -370,18 +370,15 @@ func (s *Service) awaitStateInitialized() {
 	stateChannel := make(chan *feed.Event, 1)
 	stateSub := s.stateNotifier.StateFeed().Subscribe(stateChannel)
 	defer stateSub.Unsubscribe()
-	for {
-		select {
-		case event := <-stateChannel:
-			if event.Type == statefeed.Initialized {
-				data, ok := event.Data.(*statefeed.InitializedData)
-				if !ok {
-					log.Fatalf("Received wrong data over state initialized feed: %v", data)
-				}
-				s.genesisTime = data.StartTime
-				s.genesisValidatorsRoot = data.GenesisValidatorsRoot
-				return
+	for event := range stateChannel {
+		if event.Type == statefeed.Initialized {
+			data, ok := event.Data.(*statefeed.InitializedData)
+			if !ok {
+				log.Fatalf("Received wrong data over state initialized feed: %v", data)
 			}
+			s.genesisTime = data.StartTime
+			s.genesisValidatorsRoot = data.GenesisValidatorsRoot
+			return
 		}
 	}
 }

beacon-chain/p2p/testing/mock_peermanager.go

@@ -36,16 +36,12 @@ func (m MockPeerManager) ENR() *enr.Record {
 }
 
 // RefreshENR .
-func (m MockPeerManager) RefreshENR() {
-	return
-}
+func (m MockPeerManager) RefreshENR() {}
 
 // FindPeersWithSubnet .
 func (m MockPeerManager) FindPeersWithSubnet(ctx context.Context, index uint64) (bool, error) {
 	return true, nil
 }
 
 // AddPingMethod .
-func (m MockPeerManager) AddPingMethod(reqFunc func(ctx context.Context, id peer.ID) error) {
-	return
-}
+func (m MockPeerManager) AddPingMethod(reqFunc func(ctx context.Context, id peer.ID) error) {}

beacon-chain/p2p/testing/p2p.go

@@ -318,9 +318,7 @@ func (p *TestP2P) FindPeersWithSubnet(ctx context.Context, index uint64) (bool,
 }
 
 // RefreshENR mocks the p2p func.
-func (p *TestP2P) RefreshENR() {
-	return
-}
+func (p *TestP2P) RefreshENR() {}
 
 // ForkDigest mocks the p2p func.
 func (p *TestP2P) ForkDigest() ([4]byte, error) {