Refactor verifyAttestationIndices method (#8309)

* Refactor verifyAttestationIndices

* Conflict

Co-authored-by: Raul Jordan <raul@prysmaticlabs.com>

beacon-chain/blockchain/process_attestation.go

@@ -7,6 +7,7 @@ import (
 	ethpb "github.com/prysmaticlabs/ethereumapis/eth/v1alpha1"
 	"github.com/prysmaticlabs/prysm/beacon-chain/core/helpers"
 	stateTrie "github.com/prysmaticlabs/prysm/beacon-chain/state"
+	"github.com/prysmaticlabs/prysm/shared/attestationutil"
 	"github.com/prysmaticlabs/prysm/shared/bytesutil"
 	"github.com/prysmaticlabs/prysm/shared/params"
 	"github.com/prysmaticlabs/prysm/shared/timeutils"
@@ -82,11 +83,18 @@ func (s *Service) onAttestation(ctx context.Context, a *ethpb.Attestation) error
 		return err
 	}
 
-	// Use the target state to validate attestation and calculate the committees.
-	indexedAtt, err := s.verifyAttestationIndices(ctx, baseState, a)
+	// Use the target state to verify attesting indices are valid.
+	committee, err := helpers.BeaconCommitteeFromState(baseState, a.Data.Slot, a.Data.CommitteeIndex)
 	if err != nil {
 		return err
 	}
+	indexedAtt, err := attestationutil.ConvertToIndexed(ctx, a, committee)
+	if err != nil {
+		return err
+	}
+	if err := attestationutil.IsValidAttestationIndices(ctx, indexedAtt); err != nil {
+		return err
+	}
 
 	// Note that signature verification is ignored here because it was performed in sync's validation pipeline:
 	// validate_aggregate_proof.go and validate_beacon_attestation.go

beacon-chain/blockchain/process_attestation_helpers.go

@@ -10,7 +10,6 @@ import (
 	"github.com/prysmaticlabs/prysm/beacon-chain/core/helpers"
 	"github.com/prysmaticlabs/prysm/beacon-chain/core/state"
 	stateTrie "github.com/prysmaticlabs/prysm/beacon-chain/state"
-	"github.com/prysmaticlabs/prysm/shared/attestationutil"
 	"github.com/prysmaticlabs/prysm/shared/bytesutil"
 	"github.com/prysmaticlabs/prysm/shared/mputil"
 	"github.com/prysmaticlabs/prysm/shared/params"
@@ -102,19 +101,3 @@ func (s *Service) verifyBeaconBlock(ctx context.Context, data *ethpb.Attestation
 	}
 	return nil
 }
-
-// verifyAttestationIndices validates input attestation has valid attesting indices.
-func (s *Service) verifyAttestationIndices(ctx context.Context, baseState *stateTrie.BeaconState, a *ethpb.Attestation) (*ethpb.IndexedAttestation, error) {
-	committee, err := helpers.BeaconCommitteeFromState(baseState, a.Data.Slot, a.Data.CommitteeIndex)
-	if err != nil {
-		return nil, err
-	}
-	indexedAtt, err := attestationutil.ConvertToIndexed(ctx, a, committee)
-	if err != nil {
-		return nil, err
-	}
-	if err := attestationutil.IsValidAttestationIndices(ctx, indexedAtt); err != nil {
-		return nil, err
-	}
-	return indexedAtt, nil
-}