Refactor on_attestation return signature (#8310)

* Update func on_attestation's return signature

* Add return

beacon-chain/blockchain/process_attestation.go

@@ -39,15 +39,15 @@ var ErrTargetRootNotInDB = errors.New("target root does not exist in db")
 //
 //    # Update latest messages for attesting indices
 //    update_latest_messages(store, indexed_attestation.attesting_indices, attestation)
-func (s *Service) onAttestation(ctx context.Context, a *ethpb.Attestation) ([]uint64, error) {
+func (s *Service) onAttestation(ctx context.Context, a *ethpb.Attestation) error {
 	ctx, span := trace.StartSpan(ctx, "blockChain.onAttestation")
 	defer span.End()
 
 	if err := helpers.ValidateNilAttestation(a); err != nil {
-		return nil, err
+		return err
 	}
 	if err := helpers.ValidateSlotTargetEpoch(a.Data); err != nil {
-		return nil, err
+		return err
 	}
 	tgt := stateTrie.CopyCheckpoint(a.Data.Target)
 
@@ -59,19 +59,19 @@ func (s *Service) onAttestation(ctx context.Context, a *ethpb.Attestation) ([]ui
 	// save it to the cache.
 	baseState, err := s.getAttPreState(ctx, tgt)
 	if err != nil {
-		return nil, err
+		return err
 	}
 
 	genesisTime := baseState.GenesisTime()
 
 	// Verify attestation target is from current epoch or previous epoch.
 	if err := s.verifyAttTargetEpoch(ctx, genesisTime, uint64(timeutils.Now().Unix()), tgt); err != nil {
-		return nil, err
+		return err
 	}
 
 	// Verify attestation beacon block is known and not from the future.
 	if err := s.verifyBeaconBlock(ctx, a.Data); err != nil {
-		return nil, errors.Wrap(err, "could not verify attestation beacon block")
+		return errors.Wrap(err, "could not verify attestation beacon block")
 	}
 
 	// Note that LMG GHOST and FFG consistency check is ignored because it was performed in sync's validation pipeline:
@@ -79,13 +79,13 @@ func (s *Service) onAttestation(ctx context.Context, a *ethpb.Attestation) ([]ui
 
 	// Verify attestations can only affect the fork choice of subsequent slots.
 	if err := helpers.VerifySlotTime(genesisTime, a.Data.Slot+1, params.BeaconNetworkConfig().MaximumGossipClockDisparity); err != nil {
-		return nil, err
+		return err
 	}
 
 	// Use the target state to validate attestation and calculate the committees.
 	indexedAtt, err := s.verifyAttestationIndices(ctx, baseState, a)
 	if err != nil {
-		return nil, err
+		return err
 	}
 
 	// Note that signature verification is ignored here because it was performed in sync's validation pipeline:
@@ -95,5 +95,5 @@ func (s *Service) onAttestation(ctx context.Context, a *ethpb.Attestation) ([]ui
 	// Update forkchoice store with the new attestation for updating weight.
 	s.forkChoiceStore.ProcessAttestation(ctx, indexedAtt.AttestingIndices, bytesutil.ToBytes32(a.Data.BeaconBlockRoot), a.Data.Target.Epoch)
 
-	return indexedAtt.AttestingIndices, nil
+	return nil
 }

beacon-chain/blockchain/process_attestation_test.go

@@ -114,7 +114,7 @@ func TestStore_OnAttestation_ErrorConditions(t *testing.T) {
 
 	for _, tt := range tests {
 		t.Run(tt.name, func(t *testing.T) {
-			_, err := service.onAttestation(ctx, tt.a)
+			err := service.onAttestation(ctx, tt.a)
 			if tt.wantedErr != "" {
 				assert.ErrorContains(t, tt.wantedErr, err)
 			} else {
@@ -146,11 +146,7 @@ func TestStore_OnAttestation_Ok(t *testing.T) {
 	require.NoError(t, err)
 	require.NoError(t, service.beaconDB.SaveState(ctx, copied, tRoot))
 	require.NoError(t, service.forkChoiceStore.ProcessBlock(ctx, 0, tRoot, tRoot, tRoot, 1, 1))
-	indices, err := service.onAttestation(ctx, att[0])
+	require.NoError(t, service.onAttestation(ctx, att[0]))
-	require.NoError(t, err)
-	wanted, err := helpers.BeaconCommitteeFromState(copied, 0, 0)
-	require.NoError(t, err)
-	require.DeepEqual(t, wanted, indices)
 }
 
 func TestStore_SaveCheckpointState(t *testing.T) {

beacon-chain/blockchain/receive_attestation.go

@@ -35,8 +35,7 @@ func (s *Service) ReceiveAttestationNoPubsub(ctx context.Context, att *ethpb.Att
 	ctx, span := trace.StartSpan(ctx, "beacon-chain.blockchain.ReceiveAttestationNoPubsub")
 	defer span.End()
 
-	_, err := s.onAttestation(ctx, att)
+	if err := s.onAttestation(ctx, att); err != nil {
-	if err != nil {
 		return errors.Wrap(err, "could not process attestation")
 	}