Fix linting.

api/v1/forkchoice.go

@@ -108,15 +108,15 @@ var ForkChoiceNodeValidityStrings = [...]string{
 }
 
 func ForkChoiceNodeValidityFromString(input string) (ForkChoiceNodeValidity, error) {
-	switch strings.ToLower(string(input)) {
+	switch strings.ToLower(input) {
 	case "invalid":
 		return ForkChoiceNodeValidityInvalid, nil
 	case "valid":
 		return ForkChoiceNodeValidityValid, nil
 	case "optimistic":
 		return ForkChoiceNodeValidityOptimistic, nil
 	default:
-		return ForkChoiceNodeValidityUnknown, fmt.Errorf("unrecognised fork choice validity: %s", string(input))
+		return ForkChoiceNodeValidityUnknown, fmt.Errorf("unrecognised fork choice validity: %s", input)
 	}
 }
 

api/v1/forkchoice_test.go

@@ -5,8 +5,8 @@ import (
 	"testing"
 
 	api "github.com/attestantio/go-eth2-client/api/v1"
+	"github.com/stretchr/testify/assert"
 	"github.com/stretchr/testify/require"
-	"gotest.tools/assert"
 )
 
 func TestForkChoiceJSON(t *testing.T) {

spec/versionedsignedbeaconblock.go

@@ -297,6 +297,36 @@ func (v *VersionedSignedBeaconBlock) ProposerSlashings() ([]*phase0.ProposerSlas
 	}
 }
 
+// SyncAggregate returns the sync aggregate of the beacon block.
+func (v *VersionedSignedBeaconBlock) SyncAggregate() (*altair.SyncAggregate, error) {
+	switch v.Version {
+	case DataVersionPhase0:
+		return nil, errors.New("phase0 block does not have sync aggregate")
+	case DataVersionAltair:
+		if v.Altair == nil {
+			return nil, errors.New("no altair block")
+		}
+		return v.Altair.Message.Body.SyncAggregate, nil
+	case DataVersionBellatrix:
+		if v.Bellatrix == nil {
+			return nil, errors.New("no bellatrix block")
+		}
+		return v.Bellatrix.Message.Body.SyncAggregate, nil
+	case DataVersionCapella:
+		if v.Capella == nil {
+			return nil, errors.New("no capella block")
+		}
+		return v.Capella.Message.Body.SyncAggregate, nil
+	case DataVersionDeneb:
+		if v.Deneb == nil {
+			return nil, errors.New("no deneb block")
+		}
+		return v.Deneb.Message.Body.SyncAggregate, nil
+	default:
+		return nil, errors.New("unknown version")
+	}
+}
+
 // String returns a string version of the structure.
 func (v *VersionedSignedBeaconBlock) String() string {
 	switch v.Version {