Merge pull request #7752 from testinprod-io/tip/span-batch-types-refactor

op-node: Span Batch Type, Encoding, and Decoding Refactoring

op-batcher/batcher/channel_builder_test.go

@@ -759,7 +759,7 @@ func TestFramePublished(t *testing.T) {
 }
 
 func ChannelBuilder_PendingFrames_TotalFrames(t *testing.T, batchType uint) {
-	const tnf = 8
+	const tnf = 9
 	rng := rand.New(rand.NewSource(94572314))
 	require := require.New(t)
 	cfg := defaultTestChannelConfig
@@ -828,7 +828,7 @@ func ChannelBuilder_InputBytes(t *testing.T, batchType uint) {
 			spanBatchBuilder.AppendSingularBatch(singularBatch, l1Info.SequenceNumber)
 			rawSpanBatch, err := spanBatchBuilder.GetRawSpanBatch()
 			require.NoError(err)
-			batch := derive.NewSpanBatchData(*rawSpanBatch)
+			batch := derive.NewBatchData(rawSpanBatch)
 			var buf bytes.Buffer
 			require.NoError(batch.EncodeRLP(&buf))
 			l = buf.Len()
@@ -878,7 +878,7 @@ func ChannelBuilder_OutputBytes(t *testing.T, batchType uint) {
 func blockBatchRlpSize(t *testing.T, b *types.Block) int {
 	t.Helper()
 	singularBatch, _, err := derive.BlockToSingularBatch(b)
-	batch := derive.NewSingularBatchData(*singularBatch)
+	batch := derive.NewBatchData(singularBatch)
 	require.NoError(t, err)
 	var buf bytes.Buffer
 	require.NoError(t, batch.EncodeRLP(&buf), "RLP-encoding batch")

op-e2e/actions/garbage_channel_out.go

@@ -255,13 +255,13 @@ func blockToBatch(block *types.Block) (*derive.BatchData, error) {
 		return nil, fmt.Errorf("could not parse the L1 Info deposit: %w", err)
 	}
 
-	return &derive.BatchData{
-		SingularBatch: derive.SingularBatch{
-			ParentHash:   block.ParentHash(),
-			EpochNum:     rollup.Epoch(l1Info.Number),
-			EpochHash:    l1Info.BlockHash,
-			Timestamp:    block.Time(),
-			Transactions: opaqueTxs,
-		},
-	}, nil
+	singularBatch := &derive.SingularBatch{
+		ParentHash:   block.ParentHash(),
+		EpochNum:     rollup.Epoch(l1Info.Number),
+		EpochHash:    l1Info.BlockHash,
+		Timestamp:    block.Time(),
+		Transactions: opaqueTxs,
+	}
+
+	return derive.NewBatchData(singularBatch), nil
 }

op-node/cmd/batch_decoder/reassemble/reassemble.go

@@ -19,12 +19,12 @@ import (
 )
 
 type ChannelWithMetadata struct {
-	ID             derive.ChannelID       `json:"id"`
-	IsReady        bool                   `json:"is_ready"`
-	InvalidFrames  bool                   `json:"invalid_frames"`
-	InvalidBatches bool                   `json:"invalid_batches"`
-	Frames         []FrameWithMetadata    `json:"frames"`
-	Batches        []derive.SingularBatch `json:"batches"`
+	ID             derive.ChannelID    `json:"id"`
+	IsReady        bool                `json:"is_ready"`
+	InvalidFrames  bool                `json:"invalid_frames"`
+	InvalidBatches bool                `json:"invalid_batches"`
+	Frames         []FrameWithMetadata `json:"frames"`
+	Batches        []derive.BatchData  `json:"batches"`
 }
 
 type FrameWithMetadata struct {
@@ -104,7 +104,7 @@ func processFrames(cfg *rollup.Config, id derive.ChannelID, frames []FrameWithMe
 		}
 	}
 
-	var batches []derive.SingularBatch
+	var batches []derive.BatchData
 	invalidBatches := false
 	if ch.IsReady() {
 		br, err := derive.BatchReader(ch.Reader())
@@ -114,11 +114,7 @@ func processFrames(cfg *rollup.Config, id derive.ChannelID, frames []FrameWithMe
 					fmt.Printf("Error reading batch for channel %v. Err: %v\n", id.String(), err)
 					invalidBatches = true
 				} else {
-					if batch.BatchType != derive.SingularBatchType {
-						batches = append(batches, batch.SingularBatch)
-					} else {
-						fmt.Printf("batch-type %d is not supported", batch.BatchType)
-					}
+					batches = append(batches, *batch)
 				}
 			}
 		} else {

op-node/rollup/derive/batch.go

@@ -25,9 +25,9 @@ var encodeBufferPool = sync.Pool{
 
 const (
 	// SingularBatchType is the first version of Batch format, representing a single L2 block.
-	SingularBatchType = iota
+	SingularBatchType = 0
 	// SpanBatchType is the Batch version used after SpanBatch hard fork, representing a span of L2 blocks.
-	SpanBatchType
+	SpanBatchType = 1
 )
 
 // Batch contains information to build one or multiple L2 blocks.
@@ -39,12 +39,20 @@ type Batch interface {
 	LogContext(log.Logger) log.Logger
 }
 
-// BatchData is a composition type that contains raw data of each batch version.
-// It has encoding & decoding methods to implement typed encoding.
+// BatchData is used to represent the typed encoding & decoding.
+// and wraps around a single interface InnerBatchData.
+// Further fields such as cache can be added in the future, without embedding each type of InnerBatchData.
+// Similar design with op-geth's types.Transaction struct.
 type BatchData struct {
-	BatchType int
-	SingularBatch
-	RawSpanBatch
+	inner InnerBatchData
+}
+
+// InnerBatchData is the underlying data of a BatchData.
+// This is implemented by SingularBatch and RawSpanBatch.
+type InnerBatchData interface {
+	GetBatchType() int
+	encode(w io.Writer) error
+	decode(r *bytes.Reader) error
 }
 
 // EncodeRLP implements rlp.Encoder
@@ -58,6 +66,10 @@ func (b *BatchData) EncodeRLP(w io.Writer) error {
 	return rlp.Encode(w, buf.Bytes())
 }
 
+func (bd *BatchData) GetBatchType() uint8 {
+	return uint8(bd.inner.GetBatchType())
+}
+
 // MarshalBinary returns the canonical encoding of the batch.
 func (b *BatchData) MarshalBinary() ([]byte, error) {
 	var buf bytes.Buffer
@@ -67,16 +79,10 @@ func (b *BatchData) MarshalBinary() ([]byte, error) {
 
 // encodeTyped encodes batch type and payload for each batch type.
 func (b *BatchData) encodeTyped(buf *bytes.Buffer) error {
-	switch b.BatchType {
-	case SingularBatchType:
-		buf.WriteByte(SingularBatchType)
-		return rlp.Encode(buf, &b.SingularBatch)
-	case SpanBatchType:
-		buf.WriteByte(SpanBatchType)
-		return b.RawSpanBatch.encode(buf)
-	default:
-		return fmt.Errorf("unrecognized batch type: %d", b.BatchType)
+	if err := buf.WriteByte(b.GetBatchType()); err != nil {
+		return err
 	}
+	return b.inner.encode(buf)
 }
 
 // DecodeRLP implements rlp.Decoder
@@ -99,35 +105,28 @@ func (b *BatchData) UnmarshalBinary(data []byte) error {
 	return b.decodeTyped(data)
 }
 
-// decodeTyped decodes batch type and payload for each batch type.
+// decodeTyped decodes a typed batchData
 func (b *BatchData) decodeTyped(data []byte) error {
 	if len(data) == 0 {
-		return fmt.Errorf("batch too short")
+		return errors.New("batch too short")
 	}
+	var inner InnerBatchData
 	switch data[0] {
 	case SingularBatchType:
-		b.BatchType = SingularBatchType
-		return rlp.DecodeBytes(data[1:], &b.SingularBatch)
+		inner = new(SingularBatch)
 	case SpanBatchType:
-		b.BatchType = int(data[0])
-		return b.RawSpanBatch.decodeBytes(data[1:])
+		inner = new(RawSpanBatch)
 	default:
 		return fmt.Errorf("unrecognized batch type: %d", data[0])
 	}
-}
-
-// NewSingularBatchData creates new BatchData with SingularBatch
-func NewSingularBatchData(singularBatch SingularBatch) *BatchData {
-	return &BatchData{
-		BatchType:     SingularBatchType,
-		SingularBatch: singularBatch,
+	if err := inner.decode(bytes.NewReader(data[1:])); err != nil {
+		return err
 	}
+	b.inner = inner
+	return nil
 }
 
-// NewSpanBatchData creates new BatchData with SpanBatch
-func NewSpanBatchData(spanBatch RawSpanBatch) *BatchData {
-	return &BatchData{
-		BatchType:    SpanBatchType,
-		RawSpanBatch: spanBatch,
-	}
+// NewBatchData creates a new BatchData
+func NewBatchData(inner InnerBatchData) *BatchData {
+	return &BatchData{inner: inner}
 }

op-node/rollup/derive/batch_test.go

@@ -6,15 +6,16 @@ import (
 	"math/rand"
 	"testing"
 
-	"github.com/ethereum-optimism/optimism/op-node/rollup"
-	"github.com/ethereum-optimism/optimism/op-service/eth"
-	"github.com/ethereum-optimism/optimism/op-service/testutils"
-	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
 
 	"github.com/ethereum/go-ethereum/common"
 	"github.com/ethereum/go-ethereum/common/hexutil"
 	"github.com/ethereum/go-ethereum/core/types"
 	"github.com/ethereum/go-ethereum/rlp"
+
+	"github.com/ethereum-optimism/optimism/op-node/rollup"
+	"github.com/ethereum-optimism/optimism/op-service/eth"
+	"github.com/ethereum-optimism/optimism/op-service/testutils"
 )
 
 func RandomRawSpanBatch(rng *rand.Rand, chainId *big.Int) *RawSpanBatch {
@@ -52,8 +53,8 @@ func RandomRawSpanBatch(rng *rand.Rand, chainId *big.Int) *RawSpanBatch {
 		spanBatchPrefix: spanBatchPrefix{
 			relTimestamp:  uint64(rng.Uint32()),
 			l1OriginNum:   rng.Uint64(),
-			parentCheck:   testutils.RandomData(rng, 20),
-			l1OriginCheck: testutils.RandomData(rng, 20),
+			parentCheck:   [20]byte(testutils.RandomData(rng, 20)),
+			l1OriginCheck: [20]byte(testutils.RandomData(rng, 20)),
 		},
 		spanBatchPayload: spanBatchPayload{
 			blockCount:    blockCount,
@@ -141,40 +142,42 @@ func TestBatchRoundTrip(t *testing.T) {
 	chainID := new(big.Int).SetUint64(rng.Uint64())
 
 	batches := []*BatchData{
-		{
-			SingularBatch: SingularBatch{
+		NewBatchData(
+			&SingularBatch{
 				ParentHash:   common.Hash{},
 				EpochNum:     0,
 				Timestamp:    0,
 				Transactions: []hexutil.Bytes{},
 			},
-		},
-		{
-			SingularBatch: SingularBatch{
+		),
+		NewBatchData(
+			&SingularBatch{
 				ParentHash:   common.Hash{31: 0x42},
 				EpochNum:     1,
 				Timestamp:    1647026951,
 				Transactions: []hexutil.Bytes{[]byte{0, 0, 0}, []byte{0x76, 0xfd, 0x7c}},
 			},
-		},
-		NewSingularBatchData(*RandomSingularBatch(rng, 5, chainID)),
-		NewSingularBatchData(*RandomSingularBatch(rng, 7, chainID)),
-		NewSpanBatchData(*RandomRawSpanBatch(rng, chainID)),
-		NewSpanBatchData(*RandomRawSpanBatch(rng, chainID)),
-		NewSpanBatchData(*RandomRawSpanBatch(rng, chainID)),
+		),
+		NewBatchData(RandomSingularBatch(rng, 5, chainID)),
+		NewBatchData(RandomSingularBatch(rng, 7, chainID)),
+		NewBatchData(RandomRawSpanBatch(rng, chainID)),
+		NewBatchData(RandomRawSpanBatch(rng, chainID)),
+		NewBatchData(RandomRawSpanBatch(rng, chainID)),
 	}
 
 	for i, batch := range batches {
 		enc, err := batch.MarshalBinary()
-		assert.NoError(t, err)
+		require.NoError(t, err)
 		var dec BatchData
 		err = dec.UnmarshalBinary(enc)
-		assert.NoError(t, err)
-		if dec.BatchType == SpanBatchType {
-			_, err := dec.RawSpanBatch.derive(blockTime, genesisTimestamp, chainID)
-			assert.NoError(t, err)
+		require.NoError(t, err)
+		if dec.GetBatchType() == SpanBatchType {
+			rawSpanBatch, ok := dec.inner.(*RawSpanBatch)
+			require.True(t, ok)
+			_, err := rawSpanBatch.derive(blockTime, genesisTimestamp, chainID)
+			require.NoError(t, err)
 		}
-		assert.Equal(t, batch, &dec, "Batch not equal test case %v", i)
+		require.Equal(t, batch, &dec, "Batch not equal test case %v", i)
 	}
 }
 
@@ -185,43 +188,45 @@ func TestBatchRoundTripRLP(t *testing.T) {
 	chainID := new(big.Int).SetUint64(rng.Uint64())
 
 	batches := []*BatchData{
-		{
-			SingularBatch: SingularBatch{
+		NewBatchData(
+			&SingularBatch{
 				ParentHash:   common.Hash{},
 				EpochNum:     0,
 				Timestamp:    0,
 				Transactions: []hexutil.Bytes{},
 			},
-		},
-		{
-			SingularBatch: SingularBatch{
+		),
+		NewBatchData(
+			&SingularBatch{
 				ParentHash:   common.Hash{31: 0x42},
 				EpochNum:     1,
 				Timestamp:    1647026951,
 				Transactions: []hexutil.Bytes{[]byte{0, 0, 0}, []byte{0x76, 0xfd, 0x7c}},
 			},
-		},
-		NewSingularBatchData(*RandomSingularBatch(rng, 5, chainID)),
-		NewSingularBatchData(*RandomSingularBatch(rng, 7, chainID)),
-		NewSpanBatchData(*RandomRawSpanBatch(rng, chainID)),
-		NewSpanBatchData(*RandomRawSpanBatch(rng, chainID)),
-		NewSpanBatchData(*RandomRawSpanBatch(rng, chainID)),
+		),
+		NewBatchData(RandomSingularBatch(rng, 5, chainID)),
+		NewBatchData(RandomSingularBatch(rng, 7, chainID)),
+		NewBatchData(RandomRawSpanBatch(rng, chainID)),
+		NewBatchData(RandomRawSpanBatch(rng, chainID)),
+		NewBatchData(RandomRawSpanBatch(rng, chainID)),
 	}
 
 	for i, batch := range batches {
 		var buf bytes.Buffer
 		err := batch.EncodeRLP(&buf)
-		assert.NoError(t, err)
+		require.NoError(t, err)
 		result := buf.Bytes()
 		var dec BatchData
 		r := bytes.NewReader(result)
 		s := rlp.NewStream(r, 0)
 		err = dec.DecodeRLP(s)
-		assert.NoError(t, err)
-		if dec.BatchType == SpanBatchType {
-			_, err := dec.RawSpanBatch.derive(blockTime, genesisTimestamp, chainID)
-			assert.NoError(t, err)
+		require.NoError(t, err)
+		if dec.GetBatchType() == SpanBatchType {
+			rawSpanBatch, ok := dec.inner.(*RawSpanBatch)
+			require.True(t, ok)
+			_, err := rawSpanBatch.derive(blockTime, genesisTimestamp, chainID)
+			require.NoError(t, err)
 		}
-		assert.Equal(t, batch, &dec, "Batch not equal test case %v", i)
+		require.Equal(t, batch, &dec, "Batch not equal test case %v", i)
 	}
 }

op-node/rollup/derive/batch_tob_test.go

@@ -17,13 +17,13 @@ func FuzzBatchRoundTrip(f *testing.F) {
 		typeProvider := fuzz.NewFromGoFuzz(fuzzedData).NilChance(0).MaxDepth(10000).NumElements(0, 0x100).AllowUnexportedFields(true)
 		fuzzerutils.AddFuzzerFunctions(typeProvider)
 
+		var singularBatch SingularBatch
+		typeProvider.Fuzz(&singularBatch)
+
 		// Create our batch data from fuzzed data
 		var batchData BatchData
-		typeProvider.Fuzz(&batchData)
-
 		// force batchdata to only contain singular batch
-		batchData.BatchType = SingularBatchType
-		batchData.RawSpanBatch = RawSpanBatch{}
+		batchData.inner = &singularBatch
 
 		// Encode our batch data
 		enc, err := batchData.MarshalBinary()

op-node/rollup/derive/channel_in_reader.go

@@ -3,6 +3,7 @@ package derive
 import (
 	"bytes"
 	"context"
+	"errors"
 	"fmt"
 	"io"
 
@@ -89,22 +90,30 @@ func (cr *ChannelInReader) NextBatch(ctx context.Context) (Batch, error) {
 		cr.NextChannel()
 		return nil, NotEnoughData
 	}
-	switch batchData.BatchType {
+	switch batchData.GetBatchType() {
 	case SingularBatchType:
-		return &batchData.SingularBatch, nil
+		singularBatch, ok := batchData.inner.(*SingularBatch)
+		if !ok {
+			return nil, NewCriticalError(errors.New("failed type assertion to SingularBatch"))
+		}
+		return singularBatch, nil
 	case SpanBatchType:
 		if origin := cr.Origin(); !cr.cfg.IsSpanBatch(origin.Time) {
 			return nil, NewTemporaryError(fmt.Errorf("cannot accept span batch in L1 block %s at time %d", origin, origin.Time))
 		}
+		rawSpanBatch, ok := batchData.inner.(*RawSpanBatch)
+		if !ok {
+			return nil, NewCriticalError(errors.New("failed type assertion to SpanBatch"))
+		}
 		// If the batch type is Span batch, derive block inputs from RawSpanBatch.
-		spanBatch, err := batchData.RawSpanBatch.derive(cr.cfg.BlockTime, cr.cfg.Genesis.L2Time, cr.cfg.L2ChainID)
+		spanBatch, err := rawSpanBatch.derive(cr.cfg.BlockTime, cr.cfg.Genesis.L2Time, cr.cfg.L2ChainID)
 		if err != nil {
 			return nil, err
 		}
 		return spanBatch, nil
 	default:
 		// error is bubbled up to user, but pipeline can skip the batch and continue after.
-		return nil, NewTemporaryError(fmt.Errorf("unrecognized batch type: %w", err))
+		return nil, NewTemporaryError(fmt.Errorf("unrecognized batch type: %d", batchData.GetBatchType()))
 	}
 }
 

op-node/rollup/derive/channel_out.go

@@ -145,7 +145,7 @@ func (co *SingularChannelOut) AddSingularBatch(batch *SingularBatch, _ uint64) (
 	// We encode to a temporary buffer to determine the encoded length to
 	// ensure that the total size of all RLP elements is less than or equal to MAX_RLP_BYTES_PER_CHANNEL
 	var buf bytes.Buffer
-	if err := rlp.Encode(&buf, NewSingularBatchData(*batch)); err != nil {
+	if err := rlp.Encode(&buf, NewBatchData(batch)); err != nil {
 		return 0, err
 	}
 	if co.rlpLength+buf.Len() > MaxRLPBytesPerChannel {

op-node/rollup/derive/singular_batch.go

 package derive
 
 import (
+	"bytes"
+	"io"
+
 	"github.com/ethereum-optimism/optimism/op-node/rollup"
 	"github.com/ethereum-optimism/optimism/op-service/eth"
 	"github.com/ethereum/go-ethereum/common"
 	"github.com/ethereum/go-ethereum/common/hexutil"
 	"github.com/ethereum/go-ethereum/log"
+	"github.com/ethereum/go-ethereum/rlp"
 )
 
 // Batch format
@@ -51,3 +55,13 @@ func (b *SingularBatch) LogContext(log log.Logger) log.Logger {
 func (b *SingularBatch) Epoch() eth.BlockID {
 	return eth.BlockID{Hash: b.EpochHash, Number: uint64(b.EpochNum)}
 }
+
+// encode writes the byte encoding of SingularBatch to Writer stream
+func (b *SingularBatch) encode(w io.Writer) error {
+	return rlp.Encode(w, b)
+}
+
+// decode reads the byte encoding of SingularBatch from Reader stream
+func (b *SingularBatch) decode(r *bytes.Reader) error {
+	return rlp.Decode(r, b)
+}

op-node/rollup/derive/singular_batch_test.go

@@ -5,7 +5,7 @@ import (
 	"math/rand"
 	"testing"
 
-	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
 )
 
 func TestSingularBatchForBatchInterface(t *testing.T) {
@@ -15,7 +15,7 @@ func TestSingularBatchForBatchInterface(t *testing.T) {
 
 	singularBatch := RandomSingularBatch(rng, txCount, chainID)
 
-	assert.Equal(t, SingularBatchType, singularBatch.GetBatchType())
-	assert.Equal(t, singularBatch.Timestamp, singularBatch.GetTimestamp())
-	assert.Equal(t, singularBatch.EpochNum, singularBatch.GetEpochNum())
+	require.Equal(t, SingularBatchType, singularBatch.GetBatchType())
+	require.Equal(t, singularBatch.Timestamp, singularBatch.GetTimestamp())
+	require.Equal(t, singularBatch.EpochNum, singularBatch.GetEpochNum())
 }

op-node/rollup/derive/span_batch.go

@@ -32,10 +32,10 @@ var ErrTooBigSpanBatchSize = errors.New("span batch size limit reached")
 var ErrEmptySpanBatch = errors.New("span-batch must not be empty")
 
 type spanBatchPrefix struct {
-	relTimestamp  uint64 // Relative timestamp of the first block
-	l1OriginNum   uint64 // L1 origin number
-	parentCheck   []byte // First 20 bytes of the first block's parent hash
-	l1OriginCheck []byte // First 20 bytes of the last block's L1 origin hash
+	relTimestamp  uint64   // Relative timestamp of the first block
+	l1OriginNum   uint64   // L1 origin number
+	parentCheck   [20]byte // First 20 bytes of the first block's parent hash
+	l1OriginCheck [20]byte // First 20 bytes of the last block's L1 origin hash
 }
 
 type spanBatchPayload struct {
@@ -51,6 +51,11 @@ type RawSpanBatch struct {
 	spanBatchPayload
 }
 
+// GetBatchType returns its batch type (batch_version)
+func (b *RawSpanBatch) GetBatchType() int {
+	return SpanBatchType
+}
+
 // decodeOriginBits parses data into bp.originBits
 // originBits is bitlist right-padded to a multiple of 8 bits
 func (bp *spanBatchPayload) decodeOriginBits(r *bytes.Reader) error {
@@ -105,8 +110,7 @@ func (bp *spanBatchPrefix) decodeL1OriginNum(r *bytes.Reader) error {
 
 // decodeParentCheck parses data into bp.parentCheck
 func (bp *spanBatchPrefix) decodeParentCheck(r *bytes.Reader) error {
-	bp.parentCheck = make([]byte, 20)
-	_, err := io.ReadFull(r, bp.parentCheck)
+	_, err := io.ReadFull(r, bp.parentCheck[:])
 	if err != nil {
 		return fmt.Errorf("failed to read parent check: %w", err)
 	}
@@ -115,8 +119,7 @@ func (bp *spanBatchPrefix) decodeParentCheck(r *bytes.Reader) error {
 
 // decodeL1OriginCheck parses data into bp.decodeL1OriginCheck
 func (bp *spanBatchPrefix) decodeL1OriginCheck(r *bytes.Reader) error {
-	bp.l1OriginCheck = make([]byte, 20)
-	_, err := io.ReadFull(r, bp.l1OriginCheck)
+	_, err := io.ReadFull(r, bp.l1OriginCheck[:])
 	if err != nil {
 		return fmt.Errorf("failed to read l1 origin check: %w", err)
 	}
@@ -221,12 +224,6 @@ func (bp *spanBatchPayload) decodePayload(r *bytes.Reader) error {
 	return nil
 }
 
-// decodeBytes parses data into b from data
-func (b *RawSpanBatch) decodeBytes(data []byte) error {
-	r := bytes.NewReader(data)
-	return b.decode(r)
-}
-
 // decode reads the byte encoding of SpanBatch from Reader stream
 func (b *RawSpanBatch) decode(r *bytes.Reader) error {
 	if r.Len() > MaxSpanBatchSize {
@@ -263,7 +260,7 @@ func (bp *spanBatchPrefix) encodeL1OriginNum(w io.Writer) error {
 
 // encodeParentCheck encodes bp.parentCheck
 func (bp *spanBatchPrefix) encodeParentCheck(w io.Writer) error {
-	if _, err := w.Write(bp.parentCheck); err != nil {
+	if _, err := w.Write(bp.parentCheck[:]); err != nil {
 		return fmt.Errorf("cannot write parent check: %w", err)
 	}
 	return nil
@@ -271,7 +268,7 @@ func (bp *spanBatchPrefix) encodeParentCheck(w io.Writer) error {
 
 // encodeL1OriginCheck encodes bp.l1OriginCheck
 func (bp *spanBatchPrefix) encodeL1OriginCheck(w io.Writer) error {
-	if _, err := w.Write(bp.l1OriginCheck); err != nil {
+	if _, err := w.Write(bp.l1OriginCheck[:]); err != nil {
 		return fmt.Errorf("cannot write l1 origin check: %w", err)
 	}
 	return nil
@@ -380,17 +377,6 @@ func (b *RawSpanBatch) encode(w io.Writer) error {
 	return nil
 }
 
-// encodeBytes returns the byte encoding of SpanBatch
-func (b *RawSpanBatch) encodeBytes() ([]byte, error) {
-	buf := encodeBufferPool.Get().(*bytes.Buffer)
-	defer encodeBufferPool.Put(buf)
-	buf.Reset()
-	if err := b.encode(buf); err != nil {
-		return []byte{}, err
-	}
-	return buf.Bytes(), nil
-}
-
 // derive converts RawSpanBatch into SpanBatch, which has a list of spanBatchElement.
 // We need chain config constants to derive values for making payload attributes.
 func (b *RawSpanBatch) derive(blockTime, genesisTimestamp uint64, chainID *big.Int) (*SpanBatch, error) {
@@ -451,8 +437,8 @@ func singularBatchToElement(singularBatch *SingularBatch) *spanBatchElement {
 // SpanBatch is an implementation of Batch interface,
 // containing the input to build a span of L2 blocks in derived form (spanBatchElement)
 type SpanBatch struct {
-	parentCheck   []byte              // First 20 bytes of the first block's parent hash
-	l1OriginCheck []byte              // First 20 bytes of the last block's L1 origin hash
+	parentCheck   [20]byte            // First 20 bytes of the first block's parent hash
+	l1OriginCheck [20]byte            // First 20 bytes of the last block's L1 origin hash
 	batches       []*spanBatchElement // List of block input in derived form
 }
 
@@ -473,8 +459,8 @@ func (b *SpanBatch) LogContext(log log.Logger) log.Logger {
 	}
 	return log.New(
 		"batch_timestamp", b.batches[0].Timestamp,
-		"parent_check", hexutil.Encode(b.parentCheck),
-		"origin_check", hexutil.Encode(b.l1OriginCheck),
+		"parent_check", hexutil.Encode(b.parentCheck[:]),
+		"origin_check", hexutil.Encode(b.l1OriginCheck[:]),
 		"start_epoch_number", b.GetStartEpochNum(),
 		"end_epoch_number", b.GetBlockEpochNum(len(b.batches)-1),
 		"block_count", len(b.batches),
@@ -488,12 +474,12 @@ func (b *SpanBatch) GetStartEpochNum() rollup.Epoch {
 
 // CheckOriginHash checks if the l1OriginCheck matches the first 20 bytes of given hash, probably L1 block hash from the current canonical L1 chain.
 func (b *SpanBatch) CheckOriginHash(hash common.Hash) bool {
-	return bytes.Equal(b.l1OriginCheck, hash.Bytes()[:20])
+	return bytes.Equal(b.l1OriginCheck[:], hash.Bytes()[:20])
 }
 
 // CheckParentHash checks if the parentCheck matches the first 20 bytes of given hash, probably the current L2 safe head.
 func (b *SpanBatch) CheckParentHash(hash common.Hash) bool {
-	return bytes.Equal(b.parentCheck, hash.Bytes()[:20])
+	return bytes.Equal(b.parentCheck[:], hash.Bytes()[:20])
 }
 
 // GetBlockEpochNum returns the epoch number(L1 origin block number) of the block at the given index in the span.
@@ -520,10 +506,10 @@ func (b *SpanBatch) GetBlockCount() int {
 // updates l1OriginCheck or parentCheck if needed.
 func (b *SpanBatch) AppendSingularBatch(singularBatch *SingularBatch) {
 	if len(b.batches) == 0 {
-		b.parentCheck = singularBatch.ParentHash.Bytes()[:20]
+		copy(b.parentCheck[:], singularBatch.ParentHash.Bytes()[:20])
 	}
 	b.batches = append(b.batches, singularBatchToElement(singularBatch))
-	b.l1OriginCheck = singularBatch.EpochHash.Bytes()[:20]
+	copy(b.l1OriginCheck[:], singularBatch.EpochHash.Bytes()[:20])
 }
 
 // ToRawSpanBatch merges SingularBatch List and initialize single RawSpanBatch
@@ -541,10 +527,8 @@ func (b *SpanBatch) ToRawSpanBatch(originChangedBit uint, genesisTimestamp uint6
 	span_end := b.batches[len(b.batches)-1]
 	raw.relTimestamp = span_start.Timestamp - genesisTimestamp
 	raw.l1OriginNum = uint64(span_end.EpochNum)
-	raw.parentCheck = make([]byte, 20)
-	copy(raw.parentCheck, b.parentCheck)
-	raw.l1OriginCheck = make([]byte, 20)
-	copy(raw.l1OriginCheck, b.l1OriginCheck)
+	raw.parentCheck = b.parentCheck
+	raw.l1OriginCheck = b.l1OriginCheck
 	// spanBatchPayload
 	raw.blockCount = uint64(len(b.batches))
 	raw.originBits = new(big.Int)
@@ -608,17 +592,16 @@ func (b *SpanBatch) GetSingularBatches(l1Origins []eth.L1BlockRef, l2SafeHead et
 
 // NewSpanBatch converts given singularBatches into spanBatchElements, and creates a new SpanBatch.
 func NewSpanBatch(singularBatches []*SingularBatch) *SpanBatch {
+	spanBatch := &SpanBatch{}
 	if len(singularBatches) == 0 {
-		return &SpanBatch{}
-	}
-	spanBatch := SpanBatch{
-		parentCheck:   singularBatches[0].ParentHash.Bytes()[:20],
-		l1OriginCheck: singularBatches[len(singularBatches)-1].EpochHash.Bytes()[:20],
+		return spanBatch
 	}
+	copy(spanBatch.parentCheck[:], singularBatches[0].ParentHash.Bytes()[:20])
+	copy(spanBatch.l1OriginCheck[:], singularBatches[len(singularBatches)-1].EpochHash.Bytes()[:20])
 	for _, singularBatch := range singularBatches {
 		spanBatch.batches = append(spanBatch.batches, singularBatchToElement(singularBatch))
 	}
-	return &spanBatch
+	return spanBatch
 }
 
 // SpanBatchBuilder is a utility type to build a SpanBatch by adding a SingularBatch one by one.

op-node/rollup/derive/span_batch_test.go

@@ -30,11 +30,11 @@ func TestSpanBatchForBatchInterface(t *testing.T) {
 	spanBatch := NewSpanBatch(singularBatches)
 
 	// check interface method implementations except logging
-	assert.Equal(t, SpanBatchType, spanBatch.GetBatchType())
-	assert.Equal(t, singularBatches[0].Timestamp, spanBatch.GetTimestamp())
-	assert.Equal(t, singularBatches[0].EpochNum, spanBatch.GetStartEpochNum())
-	assert.True(t, spanBatch.CheckOriginHash(singularBatches[blockCount-1].EpochHash))
-	assert.True(t, spanBatch.CheckParentHash(singularBatches[0].ParentHash))
+	require.Equal(t, SpanBatchType, spanBatch.GetBatchType())
+	require.Equal(t, singularBatches[0].Timestamp, spanBatch.GetTimestamp())
+	require.Equal(t, singularBatches[0].EpochNum, spanBatch.GetStartEpochNum())
+	require.True(t, spanBatch.CheckOriginHash(singularBatches[blockCount-1].EpochHash))
+	require.True(t, spanBatch.CheckParentHash(singularBatches[0].ParentHash))
 }
 
 func TestEmptySpanBatch(t *testing.T) {
@@ -47,8 +47,8 @@ func TestEmptySpanBatch(t *testing.T) {
 		spanBatchPrefix: spanBatchPrefix{
 			relTimestamp:  uint64(rng.Uint32()),
 			l1OriginNum:   rng.Uint64(),
-			parentCheck:   testutils.RandomData(rng, 20),
-			l1OriginCheck: testutils.RandomData(rng, 20),
+			parentCheck:   *(*[20]byte)(testutils.RandomData(rng, 20)),
+			l1OriginCheck: *(*[20]byte)(testutils.RandomData(rng, 20)),
 		},
 		spanBatchPayload: spanBatchPayload{
 			blockCount:    0,
@@ -80,23 +80,23 @@ func TestSpanBatchOriginBits(t *testing.T) {
 
 	var buf bytes.Buffer
 	err := rawSpanBatch.encodeOriginBits(&buf)
-	assert.NoError(t, err)
+	require.NoError(t, err)
 
 	// originBit field is fixed length: single bit
 	originBitBufferLen := blockCount / 8
 	if blockCount%8 != 0 {
 		originBitBufferLen++
 	}
-	assert.Equal(t, buf.Len(), int(originBitBufferLen))
+	require.Equal(t, buf.Len(), int(originBitBufferLen))
 
 	result := buf.Bytes()
 	var sb RawSpanBatch
 	sb.blockCount = blockCount
 	r := bytes.NewReader(result)
 	err = sb.decodeOriginBits(r)
-	assert.NoError(t, err)
+	require.NoError(t, err)
 
-	assert.Equal(t, rawSpanBatch.originBits, sb.originBits)
+	require.Equal(t, rawSpanBatch.originBits, sb.originBits)
 }
 
 func TestSpanBatchPrefix(t *testing.T) {
@@ -109,15 +109,15 @@ func TestSpanBatchPrefix(t *testing.T) {
 
 	var buf bytes.Buffer
 	err := rawSpanBatch.encodePrefix(&buf)
-	assert.NoError(t, err)
+	require.NoError(t, err)
 
 	result := buf.Bytes()
 	r := bytes.NewReader(result)
 	var sb RawSpanBatch
 	err = sb.decodePrefix(r)
-	assert.NoError(t, err)
+	require.NoError(t, err)
 
-	assert.Equal(t, rawSpanBatch, &sb)
+	require.Equal(t, rawSpanBatch, &sb)
 }
 
 func TestSpanBatchRelTimestamp(t *testing.T) {
@@ -128,15 +128,15 @@ func TestSpanBatchRelTimestamp(t *testing.T) {
 
 	var buf bytes.Buffer
 	err := rawSpanBatch.encodeRelTimestamp(&buf)
-	assert.NoError(t, err)
+	require.NoError(t, err)
 
 	result := buf.Bytes()
 	r := bytes.NewReader(result)
 	var sb RawSpanBatch
 	err = sb.decodeRelTimestamp(r)
-	assert.NoError(t, err)
+	require.NoError(t, err)
 
-	assert.Equal(t, rawSpanBatch.relTimestamp, sb.relTimestamp)
+	require.Equal(t, rawSpanBatch.relTimestamp, sb.relTimestamp)
 }
 
 func TestSpanBatchL1OriginNum(t *testing.T) {
@@ -147,15 +147,15 @@ func TestSpanBatchL1OriginNum(t *testing.T) {
 
 	var buf bytes.Buffer
 	err := rawSpanBatch.encodeL1OriginNum(&buf)
-	assert.NoError(t, err)
+	require.NoError(t, err)
 
 	result := buf.Bytes()
 	r := bytes.NewReader(result)
 	var sb RawSpanBatch
 	err = sb.decodeL1OriginNum(r)
-	assert.NoError(t, err)
+	require.NoError(t, err)
 
-	assert.Equal(t, rawSpanBatch.l1OriginNum, sb.l1OriginNum)
+	require.Equal(t, rawSpanBatch.l1OriginNum, sb.l1OriginNum)
 }
 
 func TestSpanBatchParentCheck(t *testing.T) {
@@ -166,18 +166,18 @@ func TestSpanBatchParentCheck(t *testing.T) {
 
 	var buf bytes.Buffer
 	err := rawSpanBatch.encodeParentCheck(&buf)
-	assert.NoError(t, err)
+	require.NoError(t, err)
 
 	// parent check field is fixed length: 20 bytes
-	assert.Equal(t, buf.Len(), 20)
+	require.Equal(t, buf.Len(), 20)
 
 	result := buf.Bytes()
 	r := bytes.NewReader(result)
 	var sb RawSpanBatch
 	err = sb.decodeParentCheck(r)
-	assert.NoError(t, err)
+	require.NoError(t, err)
 
-	assert.Equal(t, rawSpanBatch.parentCheck, sb.parentCheck)
+	require.Equal(t, rawSpanBatch.parentCheck, sb.parentCheck)
 }
 
 func TestSpanBatchL1OriginCheck(t *testing.T) {
@@ -188,18 +188,18 @@ func TestSpanBatchL1OriginCheck(t *testing.T) {
 
 	var buf bytes.Buffer
 	err := rawSpanBatch.encodeL1OriginCheck(&buf)
-	assert.NoError(t, err)
+	require.NoError(t, err)
 
 	// l1 origin check field is fixed length: 20 bytes
-	assert.Equal(t, buf.Len(), 20)
+	require.Equal(t, buf.Len(), 20)
 
 	result := buf.Bytes()
 	r := bytes.NewReader(result)
 	var sb RawSpanBatch
 	err = sb.decodeL1OriginCheck(r)
-	assert.NoError(t, err)
+	require.NoError(t, err)
 
-	assert.Equal(t, rawSpanBatch.l1OriginCheck, sb.l1OriginCheck)
+	require.Equal(t, rawSpanBatch.l1OriginCheck, sb.l1OriginCheck)
 }
 
 func TestSpanBatchPayload(t *testing.T) {
@@ -210,18 +210,18 @@ func TestSpanBatchPayload(t *testing.T) {
 
 	var buf bytes.Buffer
 	err := rawSpanBatch.encodePayload(&buf)
-	assert.NoError(t, err)
+	require.NoError(t, err)
 
 	result := buf.Bytes()
 	r := bytes.NewReader(result)
 	var sb RawSpanBatch
 
 	err = sb.decodePayload(r)
-	assert.NoError(t, err)
+	require.NoError(t, err)
 
 	sb.txs.recoverV(chainID)
 
-	assert.Equal(t, rawSpanBatch.spanBatchPayload, sb.spanBatchPayload)
+	require.Equal(t, rawSpanBatch.spanBatchPayload, sb.spanBatchPayload)
 }
 
 func TestSpanBatchBlockCount(t *testing.T) {
@@ -232,16 +232,16 @@ func TestSpanBatchBlockCount(t *testing.T) {
 
 	var buf bytes.Buffer
 	err := rawSpanBatch.encodeBlockCount(&buf)
-	assert.NoError(t, err)
+	require.NoError(t, err)
 
 	result := buf.Bytes()
 	r := bytes.NewReader(result)
 	var sb RawSpanBatch
 
 	err = sb.decodeBlockCount(r)
-	assert.NoError(t, err)
+	require.NoError(t, err)
 
-	assert.Equal(t, rawSpanBatch.blockCount, sb.blockCount)
+	require.Equal(t, rawSpanBatch.blockCount, sb.blockCount)
 }
 
 func TestSpanBatchBlockTxCounts(t *testing.T) {
@@ -252,7 +252,7 @@ func TestSpanBatchBlockTxCounts(t *testing.T) {
 
 	var buf bytes.Buffer
 	err := rawSpanBatch.encodeBlockTxCounts(&buf)
-	assert.NoError(t, err)
+	require.NoError(t, err)
 
 	result := buf.Bytes()
 	r := bytes.NewReader(result)
@@ -260,9 +260,9 @@ func TestSpanBatchBlockTxCounts(t *testing.T) {
 
 	sb.blockCount = rawSpanBatch.blockCount
 	err = sb.decodeBlockTxCounts(r)
-	assert.NoError(t, err)
+	require.NoError(t, err)
 
-	assert.Equal(t, rawSpanBatch.blockTxCounts, sb.blockTxCounts)
+	require.Equal(t, rawSpanBatch.blockTxCounts, sb.blockTxCounts)
 }
 
 func TestSpanBatchTxs(t *testing.T) {
@@ -273,7 +273,7 @@ func TestSpanBatchTxs(t *testing.T) {
 
 	var buf bytes.Buffer
 	err := rawSpanBatch.encodeTxs(&buf)
-	assert.NoError(t, err)
+	require.NoError(t, err)
 
 	result := buf.Bytes()
 	r := bytes.NewReader(result)
@@ -281,11 +281,11 @@ func TestSpanBatchTxs(t *testing.T) {
 
 	sb.blockTxCounts = rawSpanBatch.blockTxCounts
 	err = sb.decodeTxs(r)
-	assert.NoError(t, err)
+	require.NoError(t, err)
 
 	sb.txs.recoverV(chainID)
 
-	assert.Equal(t, rawSpanBatch.txs, sb.txs)
+	require.Equal(t, rawSpanBatch.txs, sb.txs)
 }
 
 func TestSpanBatchRoundTrip(t *testing.T) {
@@ -294,16 +294,17 @@ func TestSpanBatchRoundTrip(t *testing.T) {
 
 	rawSpanBatch := RandomRawSpanBatch(rng, chainID)
 
-	result, err := rawSpanBatch.encodeBytes()
-	assert.NoError(t, err)
+	var result bytes.Buffer
+	err := rawSpanBatch.encode(&result)
+	require.NoError(t, err)
 
 	var sb RawSpanBatch
-	err = sb.decodeBytes(result)
-	assert.NoError(t, err)
+	err = sb.decode(bytes.NewReader(result.Bytes()))
+	require.NoError(t, err)
 
 	sb.txs.recoverV(chainID)
 
-	assert.Equal(t, rawSpanBatch, &sb)
+	require.Equal(t, rawSpanBatch, &sb)
 }
 
 func TestSpanBatchDerive(t *testing.T) {
@@ -321,24 +322,24 @@ func TestSpanBatchDerive(t *testing.T) {
 		spanBatch := NewSpanBatch(singularBatches)
 		originChangedBit := uint(originChangedBit)
 		rawSpanBatch, err := spanBatch.ToRawSpanBatch(originChangedBit, genesisTimeStamp, chainID)
-		assert.NoError(t, err)
+		require.NoError(t, err)
 
 		spanBatchDerived, err := rawSpanBatch.derive(l2BlockTime, genesisTimeStamp, chainID)
-		assert.NoError(t, err)
+		require.NoError(t, err)
 
 		blockCount := len(singularBatches)
-		assert.Equal(t, safeL2Head.Hash.Bytes()[:20], spanBatchDerived.parentCheck)
-		assert.Equal(t, singularBatches[blockCount-1].Epoch().Hash.Bytes()[:20], spanBatchDerived.l1OriginCheck)
-		assert.Equal(t, len(singularBatches), int(rawSpanBatch.blockCount))
+		require.Equal(t, safeL2Head.Hash.Bytes()[:20], spanBatchDerived.parentCheck[:])
+		require.Equal(t, singularBatches[blockCount-1].Epoch().Hash.Bytes()[:20], spanBatchDerived.l1OriginCheck[:])
+		require.Equal(t, len(singularBatches), int(rawSpanBatch.blockCount))
 
 		for i := 1; i < len(singularBatches); i++ {
-			assert.Equal(t, spanBatchDerived.batches[i].Timestamp, spanBatchDerived.batches[i-1].Timestamp+l2BlockTime)
+			require.Equal(t, spanBatchDerived.batches[i].Timestamp, spanBatchDerived.batches[i-1].Timestamp+l2BlockTime)
 		}
 
 		for i := 0; i < len(singularBatches); i++ {
-			assert.Equal(t, singularBatches[i].EpochNum, spanBatchDerived.batches[i].EpochNum)
-			assert.Equal(t, singularBatches[i].Timestamp, spanBatchDerived.batches[i].Timestamp)
-			assert.Equal(t, singularBatches[i].Transactions, spanBatchDerived.batches[i].Transactions)
+			require.Equal(t, singularBatches[i].EpochNum, spanBatchDerived.batches[i].EpochNum)
+			require.Equal(t, singularBatches[i].Timestamp, spanBatchDerived.batches[i].Timestamp)
+			require.Equal(t, singularBatches[i].Transactions, spanBatchDerived.batches[i].Transactions)
 		}
 	}
 }
@@ -359,7 +360,7 @@ func TestSpanBatchAppend(t *testing.T) {
 	// initialize with two singular batches
 	spanBatch2 := NewSpanBatch(singularBatches[:L])
 
-	assert.Equal(t, spanBatch, spanBatch2)
+	require.Equal(t, spanBatch, spanBatch2)
 }
 
 func TestSpanBatchMerge(t *testing.T) {
@@ -375,32 +376,32 @@ func TestSpanBatchMerge(t *testing.T) {
 		spanBatch := NewSpanBatch(singularBatches)
 		originChangedBit := uint(originChangedBit)
 		rawSpanBatch, err := spanBatch.ToRawSpanBatch(originChangedBit, genesisTimeStamp, chainID)
-		assert.NoError(t, err)
+		require.NoError(t, err)
 
 		// check span batch prefix
-		assert.Equal(t, rawSpanBatch.relTimestamp, singularBatches[0].Timestamp-genesisTimeStamp, "invalid relative timestamp")
-		assert.Equal(t, rollup.Epoch(rawSpanBatch.l1OriginNum), singularBatches[blockCount-1].EpochNum)
-		assert.Equal(t, rawSpanBatch.parentCheck, singularBatches[0].ParentHash.Bytes()[:20], "invalid parent check")
-		assert.Equal(t, rawSpanBatch.l1OriginCheck, singularBatches[blockCount-1].EpochHash.Bytes()[:20], "invalid l1 origin check")
+		require.Equal(t, rawSpanBatch.relTimestamp, singularBatches[0].Timestamp-genesisTimeStamp, "invalid relative timestamp")
+		require.Equal(t, rollup.Epoch(rawSpanBatch.l1OriginNum), singularBatches[blockCount-1].EpochNum)
+		require.Equal(t, rawSpanBatch.parentCheck[:], singularBatches[0].ParentHash.Bytes()[:20], "invalid parent check")
+		require.Equal(t, rawSpanBatch.l1OriginCheck[:], singularBatches[blockCount-1].EpochHash.Bytes()[:20], "invalid l1 origin check")
 
 		// check span batch payload
-		assert.Equal(t, int(rawSpanBatch.blockCount), len(singularBatches))
-		assert.Equal(t, rawSpanBatch.originBits.Bit(0), originChangedBit)
+		require.Equal(t, int(rawSpanBatch.blockCount), len(singularBatches))
+		require.Equal(t, rawSpanBatch.originBits.Bit(0), originChangedBit)
 		for i := 1; i < blockCount; i++ {
 			if rawSpanBatch.originBits.Bit(i) == 1 {
-				assert.Equal(t, singularBatches[i].EpochNum, singularBatches[i-1].EpochNum+1)
+				require.Equal(t, singularBatches[i].EpochNum, singularBatches[i-1].EpochNum+1)
 			} else {
-				assert.Equal(t, singularBatches[i].EpochNum, singularBatches[i-1].EpochNum)
+				require.Equal(t, singularBatches[i].EpochNum, singularBatches[i-1].EpochNum)
 			}
 		}
 		for i := 0; i < len(singularBatches); i++ {
 			txCount := len(singularBatches[i].Transactions)
-			assert.Equal(t, txCount, int(rawSpanBatch.blockTxCounts[i]))
+			require.Equal(t, txCount, int(rawSpanBatch.blockTxCounts[i]))
 		}
 
 		// check invariants
 		endEpochNum := rawSpanBatch.l1OriginNum
-		assert.Equal(t, endEpochNum, uint64(singularBatches[blockCount-1].EpochNum))
+		require.Equal(t, endEpochNum, uint64(singularBatches[blockCount-1].EpochNum))
 
 		// we do not check txs field because it has to be derived to be compared
 	}
@@ -420,12 +421,12 @@ func TestSpanBatchToSingularBatch(t *testing.T) {
 		spanBatch := NewSpanBatch(singularBatches)
 		originChangedBit := uint(originChangedBit)
 		rawSpanBatch, err := spanBatch.ToRawSpanBatch(originChangedBit, genesisTimeStamp, chainID)
-		assert.NoError(t, err)
+		require.NoError(t, err)
 
 		l1Origins := mockL1Origin(rng, rawSpanBatch, singularBatches)
 
 		singularBatches2, err := spanBatch.GetSingularBatches(l1Origins, safeL2Head)
-		assert.NoError(t, err)
+		require.NoError(t, err)
 
 		// GetSingularBatches does not fill in parent hash of singular batches
 		// empty out parent hash for comparison
@@ -434,52 +435,54 @@ func TestSpanBatchToSingularBatch(t *testing.T) {
 		}
 		// check parent hash is empty
 		for i := 0; i < len(singularBatches2); i++ {
-			assert.Equal(t, singularBatches2[i].ParentHash, common.Hash{})
+			require.Equal(t, singularBatches2[i].ParentHash, common.Hash{})
 		}
 
-		assert.Equal(t, singularBatches, singularBatches2)
+		require.Equal(t, singularBatches, singularBatches2)
 	}
 }
 
 func TestSpanBatchReadTxData(t *testing.T) {
-	rng := rand.New(rand.NewSource(0x109550))
-	chainID := new(big.Int).SetUint64(rng.Uint64())
-
-	txCount := 64
-
-	signer := types.NewLondonSigner(chainID)
-	var rawTxs [][]byte
-	var txs []*types.Transaction
-	m := make(map[byte]int)
-	for i := 0; i < txCount; i++ {
-		tx := testutils.RandomTx(rng, new(big.Int).SetUint64(rng.Uint64()), signer)
-		m[tx.Type()] += 1
-		rawTx, err := tx.MarshalBinary()
-		assert.NoError(t, err)
-		rawTxs = append(rawTxs, rawTx)
-		txs = append(txs, tx)
+	cases := []spanBatchTxTest{
+		{"legacy tx", 32, testutils.RandomLegacyTx},
+		{"access list tx", 32, testutils.RandomAccessListTx},
+		{"dynamic fee tx", 32, testutils.RandomDynamicFeeTx},
 	}
 
-	for i := 0; i < txCount; i++ {
-		r := bytes.NewReader(rawTxs[i])
-		_, txType, err := ReadTxData(r)
-		assert.NoError(t, err)
-		assert.Equal(t, int(txs[i].Type()), txType)
+	for i, testCase := range cases {
+		t.Run(testCase.name, func(t *testing.T) {
+			rng := rand.New(rand.NewSource(int64(0x109550 + i)))
+			chainID := new(big.Int).SetUint64(rng.Uint64())
+			signer := types.NewLondonSigner(chainID)
+
+			var rawTxs [][]byte
+			var txs []*types.Transaction
+			for txIdx := 0; txIdx < testCase.trials; txIdx++ {
+				tx := testCase.mkTx(rng, signer)
+				rawTx, err := tx.MarshalBinary()
+				require.NoError(t, err)
+				rawTxs = append(rawTxs, rawTx)
+				txs = append(txs, tx)
+			}
+
+			for txIdx := 0; txIdx < testCase.trials; txIdx++ {
+				r := bytes.NewReader(rawTxs[i])
+				_, txType, err := ReadTxData(r)
+				require.NoError(t, err)
+				assert.Equal(t, int(txs[i].Type()), txType)
+			}
+		})
 	}
-	// make sure every tx type is tested
-	assert.Positive(t, m[types.LegacyTxType])
-	assert.Positive(t, m[types.AccessListTxType])
-	assert.Positive(t, m[types.DynamicFeeTxType])
 }
 
 func TestSpanBatchReadTxDataInvalid(t *testing.T) {
 	dummy, err := rlp.EncodeToBytes("dummy")
-	assert.NoError(t, err)
+	require.NoError(t, err)
 
 	// test non list rlp decoding
 	r := bytes.NewReader(dummy)
 	_, _, err = ReadTxData(r)
-	assert.ErrorContains(t, err, "tx RLP prefix type must be list")
+	require.ErrorContains(t, err, "tx RLP prefix type must be list")
 }
 
 func TestSpanBatchBuilder(t *testing.T) {
@@ -500,28 +503,28 @@ func TestSpanBatchBuilder(t *testing.T) {
 		}
 		spanBatchBuilder := NewSpanBatchBuilder(genesisTimeStamp, chainID)
 
-		assert.Equal(t, 0, spanBatchBuilder.GetBlockCount())
+		require.Equal(t, 0, spanBatchBuilder.GetBlockCount())
 
 		for i := 0; i < len(singularBatches); i++ {
 			spanBatchBuilder.AppendSingularBatch(singularBatches[i], seqNum)
-			assert.Equal(t, i+1, spanBatchBuilder.GetBlockCount())
-			assert.Equal(t, singularBatches[0].ParentHash.Bytes()[:20], spanBatchBuilder.spanBatch.parentCheck)
-			assert.Equal(t, singularBatches[i].EpochHash.Bytes()[:20], spanBatchBuilder.spanBatch.l1OriginCheck)
+			require.Equal(t, i+1, spanBatchBuilder.GetBlockCount())
+			require.Equal(t, singularBatches[0].ParentHash.Bytes()[:20], spanBatchBuilder.spanBatch.parentCheck[:])
+			require.Equal(t, singularBatches[i].EpochHash.Bytes()[:20], spanBatchBuilder.spanBatch.l1OriginCheck[:])
 		}
 
 		rawSpanBatch, err := spanBatchBuilder.GetRawSpanBatch()
-		assert.NoError(t, err)
+		require.NoError(t, err)
 
 		// compare with rawSpanBatch not using spanBatchBuilder
 		spanBatch := NewSpanBatch(singularBatches)
 		originChangedBit := uint(originChangedBit)
 		rawSpanBatch2, err := spanBatch.ToRawSpanBatch(originChangedBit, genesisTimeStamp, chainID)
-		assert.NoError(t, err)
+		require.NoError(t, err)
 
-		assert.Equal(t, rawSpanBatch2, rawSpanBatch)
+		require.Equal(t, rawSpanBatch2, rawSpanBatch)
 
 		spanBatchBuilder.Reset()
-		assert.Equal(t, 0, spanBatchBuilder.GetBlockCount())
+		require.Equal(t, 0, spanBatchBuilder.GetBlockCount())
 	}
 }
 
@@ -533,7 +536,7 @@ func TestSpanBatchMaxTxData(t *testing.T) {
 	})
 
 	txEncoded, err := invalidTx.MarshalBinary()
-	assert.NoError(t, err)
+	require.NoError(t, err)
 
 	r := bytes.NewReader(txEncoded)
 	_, _, err = ReadTxData(r)

op-node/rollup/derive/span_batch_tx.go

@@ -4,7 +4,6 @@ import (
 	"bytes"
 	"errors"
 	"fmt"
-	"io"
 	"math/big"
 
 	"github.com/ethereum/go-ethereum/common"
@@ -70,21 +69,6 @@ func (tx *spanBatchTx) MarshalBinary() ([]byte, error) {
 	return buf.Bytes(), err
 }
 
-// EncodeRLP implements rlp.Encoder
-func (tx *spanBatchTx) EncodeRLP(w io.Writer) error {
-	if tx.Type() == types.LegacyTxType {
-		return rlp.Encode(w, tx.inner)
-	}
-	// It's an EIP-2718 typed TX envelope.
-	buf := encodeBufferPool.Get().(*bytes.Buffer)
-	defer encodeBufferPool.Put(buf)
-	buf.Reset()
-	if err := tx.encodeTyped(buf); err != nil {
-		return err
-	}
-	return rlp.Encode(w, buf.Bytes())
-}
-
 // setDecoded sets the inner transaction after decoding.
 func (tx *spanBatchTx) setDecoded(inner spanBatchTxData, size uint64) {
 	tx.inner = inner
@@ -115,36 +99,6 @@ func (tx *spanBatchTx) decodeTyped(b []byte) (spanBatchTxData, error) {
 	}
 }
 
-// DecodeRLP implements rlp.Decoder
-func (tx *spanBatchTx) DecodeRLP(s *rlp.Stream) error {
-	kind, size, err := s.Kind()
-	switch {
-	case err != nil:
-		return err
-	case kind == rlp.List:
-		// It's a legacy transaction.
-		var inner spanBatchLegacyTxData
-		err = s.Decode(&inner)
-		if err != nil {
-			return fmt.Errorf("failed to decode spanBatchLegacyTxData: %w", err)
-		}
-		tx.setDecoded(&inner, rlp.ListSize(size))
-		return nil
-	default:
-		// It's an EIP-2718 typed TX envelope.
-		var b []byte
-		if b, err = s.Bytes(); err != nil {
-			return err
-		}
-		inner, err := tx.decodeTyped(b)
-		if err != nil {
-			return err
-		}
-		tx.setDecoded(inner, uint64(len(b)))
-		return nil
-	}
-}
-
 // UnmarshalBinary decodes the canonical encoding of transactions.
 // It supports legacy RLP transactions and EIP2718 typed transactions.
 func (tx *spanBatchTx) UnmarshalBinary(b []byte) error {

op-node/rollup/derive/span_batch_tx_test.go

 package derive
 
 import (
-	"bytes"
 	"math/big"
 	"math/rand"
 	"testing"
 
 	"github.com/ethereum-optimism/optimism/op-service/testutils"
 	"github.com/ethereum/go-ethereum/core/types"
-	"github.com/ethereum/go-ethereum/rlp"
 	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
 )
 
+type spanBatchTxTest struct {
+	name   string
+	trials int
+	mkTx   func(rng *rand.Rand, signer types.Signer) *types.Transaction
+}
+
 func TestSpanBatchTxConvert(t *testing.T) {
-	rng := rand.New(rand.NewSource(0x1331))
-	chainID := big.NewInt(rng.Int63n(1000))
-	signer := types.NewLondonSigner(chainID)
-
-	m := make(map[byte]int)
-	for i := 0; i < 32; i++ {
-		tx := testutils.RandomTx(rng, new(big.Int).SetUint64(rng.Uint64()), signer)
-		m[tx.Type()] += 1
-		v, r, s := tx.RawSignatureValues()
-		sbtx, err := newSpanBatchTx(*tx)
-		assert.NoError(t, err)
-
-		tx2, err := sbtx.convertToFullTx(tx.Nonce(), tx.Gas(), tx.To(), chainID, v, r, s)
-		assert.NoError(t, err)
-
-		// compare after marshal because we only need inner field of transaction
-		txEncoded, err := tx.MarshalBinary()
-		assert.NoError(t, err)
-		tx2Encoded, err := tx2.MarshalBinary()
-		assert.NoError(t, err)
-
-		assert.Equal(t, txEncoded, tx2Encoded)
+	cases := []spanBatchTxTest{
+		{"legacy tx", 32, testutils.RandomLegacyTx},
+		{"access list tx", 32, testutils.RandomAccessListTx},
+		{"dynamic fee tx", 32, testutils.RandomDynamicFeeTx},
 	}
-	// make sure every tx type is tested
-	assert.Positive(t, m[types.LegacyTxType])
-	assert.Positive(t, m[types.AccessListTxType])
-	assert.Positive(t, m[types.DynamicFeeTxType])
-}
 
-func TestSpanBatchTxRoundTrip(t *testing.T) {
-	rng := rand.New(rand.NewSource(0x1332))
-	chainID := big.NewInt(rng.Int63n(1000))
-	signer := types.NewLondonSigner(chainID)
+	for i, testCase := range cases {
+		t.Run(testCase.name, func(t *testing.T) {
+			rng := rand.New(rand.NewSource(int64(0x1331 + i)))
+			chainID := big.NewInt(rng.Int63n(1000))
+			signer := types.NewLondonSigner(chainID)
 
-	m := make(map[byte]int)
-	for i := 0; i < 32; i++ {
-		tx := testutils.RandomTx(rng, new(big.Int).SetUint64(rng.Uint64()), signer)
-		m[tx.Type()] += 1
-		sbtx, err := newSpanBatchTx(*tx)
-		assert.NoError(t, err)
+			for txIdx := 0; txIdx < testCase.trials; txIdx++ {
+				tx := testCase.mkTx(rng, signer)
 
-		sbtxEncoded, err := sbtx.MarshalBinary()
-		assert.NoError(t, err)
+				v, r, s := tx.RawSignatureValues()
+				sbtx, err := newSpanBatchTx(*tx)
+				require.NoError(t, err)
 
-		var sbtx2 spanBatchTx
-		err = sbtx2.UnmarshalBinary(sbtxEncoded)
-		assert.NoError(t, err)
+				tx2, err := sbtx.convertToFullTx(tx.Nonce(), tx.Gas(), tx.To(), chainID, v, r, s)
+				require.NoError(t, err)
 
-		assert.Equal(t, sbtx, &sbtx2)
+				// compare after marshal because we only need inner field of transaction
+				txEncoded, err := tx.MarshalBinary()
+				require.NoError(t, err)
+				tx2Encoded, err := tx2.MarshalBinary()
+				require.NoError(t, err)
+
+				assert.Equal(t, txEncoded, tx2Encoded)
+			}
+		})
 	}
-	// make sure every tx type is tested
-	assert.Positive(t, m[types.LegacyTxType])
-	assert.Positive(t, m[types.AccessListTxType])
-	assert.Positive(t, m[types.DynamicFeeTxType])
 }
 
-func TestSpanBatchTxRoundTripRLP(t *testing.T) {
-	rng := rand.New(rand.NewSource(0x1333))
-	chainID := big.NewInt(rng.Int63n(1000))
-	signer := types.NewLondonSigner(chainID)
-
-	m := make(map[byte]int)
-	for i := 0; i < 32; i++ {
-		tx := testutils.RandomTx(rng, new(big.Int).SetUint64(rng.Uint64()), signer)
-		m[tx.Type()] += 1
-		sbtx, err := newSpanBatchTx(*tx)
-		assert.NoError(t, err)
-
-		var buf bytes.Buffer
-		err = sbtx.EncodeRLP(&buf)
-		assert.NoError(t, err)
-
-		result := buf.Bytes()
-		var sbtx2 spanBatchTx
-		r := bytes.NewReader(result)
-		rlpReader := rlp.NewStream(r, 0)
-		err = sbtx2.DecodeRLP(rlpReader)
-		assert.NoError(t, err)
-
-		assert.Equal(t, sbtx, &sbtx2)
+func TestSpanBatchTxRoundTrip(t *testing.T) {
+	cases := []spanBatchTxTest{
+		{"legacy tx", 32, testutils.RandomLegacyTx},
+		{"access list tx", 32, testutils.RandomAccessListTx},
+		{"dynamic fee tx", 32, testutils.RandomDynamicFeeTx},
+	}
+
+	for i, testCase := range cases {
+		t.Run(testCase.name, func(t *testing.T) {
+			rng := rand.New(rand.NewSource(int64(0x1332 + i)))
+			chainID := big.NewInt(rng.Int63n(1000))
+			signer := types.NewLondonSigner(chainID)
+
+			for txIdx := 0; txIdx < testCase.trials; txIdx++ {
+				tx := testCase.mkTx(rng, signer)
+
+				sbtx, err := newSpanBatchTx(*tx)
+				require.NoError(t, err)
+
+				sbtxEncoded, err := sbtx.MarshalBinary()
+				require.NoError(t, err)
+
+				var sbtx2 spanBatchTx
+				err = sbtx2.UnmarshalBinary(sbtxEncoded)
+				require.NoError(t, err)
+
+				assert.Equal(t, sbtx, &sbtx2)
+			}
+		})
 	}
-	// make sure every tx type is tested
-	assert.Positive(t, m[types.LegacyTxType])
-	assert.Positive(t, m[types.AccessListTxType])
-	assert.Positive(t, m[types.DynamicFeeTxType])
 }
 
 type spanBatchDummyTxData struct{}
@@ -107,44 +91,44 @@ func TestSpanBatchTxInvalidTxType(t *testing.T) {
 	// span batch never contain deposit tx
 	depositTx := types.NewTx(&types.DepositTx{})
 	_, err := newSpanBatchTx(*depositTx)
-	assert.ErrorContains(t, err, "invalid tx type")
+	require.ErrorContains(t, err, "invalid tx type")
 
 	var sbtx spanBatchTx
 	sbtx.inner = &spanBatchDummyTxData{}
 	_, err = sbtx.convertToFullTx(0, 0, nil, nil, nil, nil, nil)
-	assert.ErrorContains(t, err, "invalid tx type")
+	require.ErrorContains(t, err, "invalid tx type")
 }
 
 func TestSpanBatchTxDecodeInvalid(t *testing.T) {
 	var sbtx spanBatchTx
 	_, err := sbtx.decodeTyped([]byte{})
-	assert.EqualError(t, err, "typed transaction too short")
+	require.EqualError(t, err, "typed transaction too short")
 
 	tx := types.NewTx(&types.LegacyTx{})
 	txEncoded, err := tx.MarshalBinary()
-	assert.NoError(t, err)
+	require.NoError(t, err)
 
 	// legacy tx is not typed tx
 	_, err = sbtx.decodeTyped(txEncoded)
-	assert.EqualError(t, err, types.ErrTxTypeNotSupported.Error())
+	require.EqualError(t, err, types.ErrTxTypeNotSupported.Error())
 
 	tx2 := types.NewTx(&types.AccessListTx{})
 	tx2Encoded, err := tx2.MarshalBinary()
-	assert.NoError(t, err)
+	require.NoError(t, err)
 
 	tx2Encoded[0] = types.DynamicFeeTxType
 	_, err = sbtx.decodeTyped(tx2Encoded)
-	assert.ErrorContains(t, err, "failed to decode spanBatchDynamicFeeTxData")
+	require.ErrorContains(t, err, "failed to decode spanBatchDynamicFeeTxData")
 
 	tx3 := types.NewTx(&types.DynamicFeeTx{})
 	tx3Encoded, err := tx3.MarshalBinary()
-	assert.NoError(t, err)
+	require.NoError(t, err)
 
 	tx3Encoded[0] = types.AccessListTxType
 	_, err = sbtx.decodeTyped(tx3Encoded)
-	assert.ErrorContains(t, err, "failed to decode spanBatchAccessListTxData")
+	require.ErrorContains(t, err, "failed to decode spanBatchAccessListTxData")
 
 	invalidLegacyTxDecoded := []byte{0xFF, 0xFF}
 	err = sbtx.UnmarshalBinary(invalidLegacyTxDecoded)
-	assert.ErrorContains(t, err, "failed to decode spanBatchLegacyTxData")
+	require.ErrorContains(t, err, "failed to decode spanBatchLegacyTxData")
 }

op-node/rollup/derive/span_batch_txs_test.go

@@ -6,11 +6,12 @@ import (
 	"math/rand"
 	"testing"
 
-	"github.com/ethereum-optimism/optimism/op-service/testutils"
-	"github.com/ethereum/go-ethereum/core/types"
 	"github.com/holiman/uint256"
-	"github.com/stretchr/testify/assert"
 	"github.com/stretchr/testify/require"
+
+	"github.com/ethereum/go-ethereum/core/types"
+
+	"github.com/ethereum-optimism/optimism/op-service/testutils"
 )
 
 func TestSpanBatchTxsContractCreationBits(t *testing.T) {
@@ -27,23 +28,23 @@ func TestSpanBatchTxsContractCreationBits(t *testing.T) {
 
 	var buf bytes.Buffer
 	err := sbt.encodeContractCreationBits(&buf)
-	assert.NoError(t, err)
+	require.NoError(t, err)
 
 	// contractCreationBit field is fixed length: single bit
 	contractCreationBitBufferLen := totalBlockTxCount / 8
 	if totalBlockTxCount%8 != 0 {
 		contractCreationBitBufferLen++
 	}
-	assert.Equal(t, buf.Len(), int(contractCreationBitBufferLen))
+	require.Equal(t, buf.Len(), int(contractCreationBitBufferLen))
 
 	result := buf.Bytes()
 	sbt.contractCreationBits = nil
 
 	r := bytes.NewReader(result)
 	err = sbt.decodeContractCreationBits(r)
-	assert.NoError(t, err)
+	require.NoError(t, err)
 
-	assert.Equal(t, contractCreationBits, sbt.contractCreationBits)
+	require.Equal(t, contractCreationBits, sbt.contractCreationBits)
 }
 
 func TestSpanBatchTxsContractCreationCount(t *testing.T) {
@@ -62,16 +63,16 @@ func TestSpanBatchTxsContractCreationCount(t *testing.T) {
 
 	var buf bytes.Buffer
 	err := sbt.encodeContractCreationBits(&buf)
-	assert.NoError(t, err)
+	require.NoError(t, err)
 
 	result := buf.Bytes()
 	sbt.contractCreationBits = nil
 
 	r := bytes.NewReader(result)
 	err = sbt.decodeContractCreationBits(r)
-	assert.NoError(t, err)
+	require.NoError(t, err)
 
-	assert.Equal(t, contractCreationCount, sbt.contractCreationCount())
+	require.Equal(t, contractCreationCount, sbt.contractCreationCount())
 }
 
 func TestSpanBatchTxsYParityBits(t *testing.T) {
@@ -88,23 +89,23 @@ func TestSpanBatchTxsYParityBits(t *testing.T) {
 
 	var buf bytes.Buffer
 	err := sbt.encodeYParityBits(&buf)
-	assert.NoError(t, err)
+	require.NoError(t, err)
 
 	// yParityBit field is fixed length: single bit
 	yParityBitBufferLen := totalBlockTxCount / 8
 	if totalBlockTxCount%8 != 0 {
 		yParityBitBufferLen++
 	}
-	assert.Equal(t, buf.Len(), int(yParityBitBufferLen))
+	require.Equal(t, buf.Len(), int(yParityBitBufferLen))
 
 	result := buf.Bytes()
 	sbt.yParityBits = nil
 
 	r := bytes.NewReader(result)
 	err = sbt.decodeYParityBits(r)
-	assert.NoError(t, err)
+	require.NoError(t, err)
 
-	assert.Equal(t, yParityBits, sbt.yParityBits)
+	require.Equal(t, yParityBits, sbt.yParityBits)
 }
 
 func TestSpanBatchTxsTxSigs(t *testing.T) {
@@ -121,22 +122,22 @@ func TestSpanBatchTxsTxSigs(t *testing.T) {
 
 	var buf bytes.Buffer
 	err := sbt.encodeTxSigsRS(&buf)
-	assert.NoError(t, err)
+	require.NoError(t, err)
 
 	// txSig field is fixed length: 32 byte + 32 byte = 64 byte
-	assert.Equal(t, buf.Len(), 64*int(totalBlockTxCount))
+	require.Equal(t, buf.Len(), 64*int(totalBlockTxCount))
 
 	result := buf.Bytes()
 	sbt.txSigs = nil
 
 	r := bytes.NewReader(result)
 	err = sbt.decodeTxSigsRS(r)
-	assert.NoError(t, err)
+	require.NoError(t, err)
 
 	// v field is not set
 	for i := 0; i < int(totalBlockTxCount); i++ {
-		assert.Equal(t, txSigs[i].r, sbt.txSigs[i].r)
-		assert.Equal(t, txSigs[i].s, sbt.txSigs[i].s)
+		require.Equal(t, txSigs[i].r, sbt.txSigs[i].r)
+		require.Equal(t, txSigs[i].s, sbt.txSigs[i].s)
 	}
 }
 
@@ -154,16 +155,16 @@ func TestSpanBatchTxsTxNonces(t *testing.T) {
 
 	var buf bytes.Buffer
 	err := sbt.encodeTxNonces(&buf)
-	assert.NoError(t, err)
+	require.NoError(t, err)
 
 	result := buf.Bytes()
 	sbt.txNonces = nil
 
 	r := bytes.NewReader(result)
 	err = sbt.decodeTxNonces(r)
-	assert.NoError(t, err)
+	require.NoError(t, err)
 
-	assert.Equal(t, txNonces, sbt.txNonces)
+	require.Equal(t, txNonces, sbt.txNonces)
 }
 
 func TestSpanBatchTxsTxGases(t *testing.T) {
@@ -180,16 +181,16 @@ func TestSpanBatchTxsTxGases(t *testing.T) {
 
 	var buf bytes.Buffer
 	err := sbt.encodeTxGases(&buf)
-	assert.NoError(t, err)
+	require.NoError(t, err)
 
 	result := buf.Bytes()
 	sbt.txGases = nil
 
 	r := bytes.NewReader(result)
 	err = sbt.decodeTxGases(r)
-	assert.NoError(t, err)
+	require.NoError(t, err)
 
-	assert.Equal(t, txGases, sbt.txGases)
+	require.Equal(t, txGases, sbt.txGases)
 }
 
 func TestSpanBatchTxsTxTos(t *testing.T) {
@@ -209,19 +210,19 @@ func TestSpanBatchTxsTxTos(t *testing.T) {
 
 	var buf bytes.Buffer
 	err := sbt.encodeTxTos(&buf)
-	assert.NoError(t, err)
+	require.NoError(t, err)
 
 	// to field is fixed length: 20 bytes
-	assert.Equal(t, buf.Len(), 20*len(txTos))
+	require.Equal(t, buf.Len(), 20*len(txTos))
 
 	result := buf.Bytes()
 	sbt.txTos = nil
 
 	r := bytes.NewReader(result)
 	err = sbt.decodeTxTos(r)
-	assert.NoError(t, err)
+	require.NoError(t, err)
 
-	assert.Equal(t, txTos, sbt.txTos)
+	require.Equal(t, txTos, sbt.txTos)
 }
 
 func TestSpanBatchTxsTxDatas(t *testing.T) {
@@ -240,7 +241,7 @@ func TestSpanBatchTxsTxDatas(t *testing.T) {
 
 	var buf bytes.Buffer
 	err := sbt.encodeTxDatas(&buf)
-	assert.NoError(t, err)
+	require.NoError(t, err)
 
 	result := buf.Bytes()
 	sbt.txDatas = nil
@@ -248,10 +249,10 @@ func TestSpanBatchTxsTxDatas(t *testing.T) {
 
 	r := bytes.NewReader(result)
 	err = sbt.decodeTxDatas(r)
-	assert.NoError(t, err)
+	require.NoError(t, err)
 
-	assert.Equal(t, txDatas, sbt.txDatas)
-	assert.Equal(t, txTypes, sbt.txTypes)
+	require.Equal(t, txDatas, sbt.txDatas)
+	require.Equal(t, txTypes, sbt.txTypes)
 }
 
 func TestSpanBatchTxsRecoverV(t *testing.T) {
@@ -291,7 +292,7 @@ func TestSpanBatchTxsRecoverV(t *testing.T) {
 		recoveredVs = append(recoveredVs, txSig.v)
 	}
 
-	assert.Equal(t, originalVs, recoveredVs, "recovered v mismatch")
+	require.Equal(t, originalVs, recoveredVs, "recovered v mismatch")
 }
 
 func TestSpanBatchTxsRoundTrip(t *testing.T) {
@@ -305,7 +306,7 @@ func TestSpanBatchTxsRoundTrip(t *testing.T) {
 
 		var buf bytes.Buffer
 		err := sbt.encode(&buf)
-		assert.NoError(t, err)
+		require.NoError(t, err)
 
 		result := buf.Bytes()
 		r := bytes.NewReader(result)
@@ -313,10 +314,10 @@ func TestSpanBatchTxsRoundTrip(t *testing.T) {
 		var sbt2 spanBatchTxs
 		sbt2.totalBlockTxCount = totalBlockTxCount
 		err = sbt2.decode(r)
-		assert.NoError(t, err)
+		require.NoError(t, err)
 		sbt2.recoverV(chainID)
 
-		assert.Equal(t, sbt, &sbt2)
+		require.Equal(t, sbt, &sbt2)
 	}
 }
 
@@ -331,16 +332,16 @@ func TestSpanBatchTxsRoundTripFullTxs(t *testing.T) {
 		for i := 0; i < int(totalblockTxCounts); i++ {
 			tx := testutils.RandomTx(rng, new(big.Int).SetUint64(rng.Uint64()), signer)
 			rawTx, err := tx.MarshalBinary()
-			assert.NoError(t, err)
+			require.NoError(t, err)
 			txs = append(txs, rawTx)
 		}
 		sbt, err := newSpanBatchTxs(txs, chainID)
-		assert.NoError(t, err)
+		require.NoError(t, err)
 
 		txs2, err := sbt.fullTxs(chainID)
-		assert.NoError(t, err)
+		require.NoError(t, err)
 
-		assert.Equal(t, txs, txs2)
+		require.Equal(t, txs, txs2)
 	}
 }
 
@@ -373,17 +374,17 @@ func TestSpanBatchTxsFullTxNotEnoughTxTos(t *testing.T) {
 	for i := 0; i < int(totalblockTxCounts); i++ {
 		tx := testutils.RandomTx(rng, new(big.Int).SetUint64(rng.Uint64()), signer)
 		rawTx, err := tx.MarshalBinary()
-		assert.NoError(t, err)
+		require.NoError(t, err)
 		txs = append(txs, rawTx)
 	}
 	sbt, err := newSpanBatchTxs(txs, chainID)
-	assert.NoError(t, err)
+	require.NoError(t, err)
 
 	// drop single to field
 	sbt.txTos = sbt.txTos[:len(sbt.txTos)-2]
 
 	_, err = sbt.fullTxs(chainID)
-	assert.EqualError(t, err, "tx to not enough")
+	require.EqualError(t, err, "tx to not enough")
 }
 
 func TestSpanBatchTxsMaxContractCreationBitsLength(t *testing.T) {

op-node/rollup/derive/span_channel_out.go

@@ -106,12 +106,12 @@ func (co *SpanChannelOut) AddSingularBatch(batch *SingularBatch, seqNum uint64)
 		return 0, fmt.Errorf("failed to convert SpanBatch into RawSpanBatch: %w", err)
 	}
 	// Encode RawSpanBatch into bytes
-	if err = rlp.Encode(&buf, NewSpanBatchData(*rawSpanBatch)); err != nil {
+	if err = rlp.Encode(&buf, NewBatchData(rawSpanBatch)); err != nil {
 		return 0, fmt.Errorf("failed to encode RawSpanBatch into bytes: %w", err)
 	}
 	// Ensure that the total size of all RLP elements is less than or equal to MAX_RLP_BYTES_PER_CHANNEL
 	if buf.Len() > MaxRLPBytesPerChannel {
-		return 0, fmt.Errorf("could not add %d bytes to channel of %d bytes, max is %d. err: %w",
+		return 0, fmt.Errorf("could not take %d bytes as replacement of channel of %d bytes, max is %d. err: %w",
 			buf.Len(), co.rlpLength, MaxRLPBytesPerChannel, ErrTooManyRLPBytes)
 	}
 	co.rlpLength = buf.Len()

op-service/testutils/random.go

@@ -141,49 +141,72 @@ func RandomTo(rng *rand.Rand) *common.Address {
 }
 
 func RandomTx(rng *rand.Rand, baseFee *big.Int, signer types.Signer) *types.Transaction {
-	gas := params.TxGas + uint64(rng.Int63n(2_000_000))
-	key := InsecureRandomKey(rng)
-	tip := big.NewInt(rng.Int63n(10 * params.GWei))
-
 	txTypeList := []int{types.LegacyTxType, types.AccessListTxType, types.DynamicFeeTxType}
 	txType := txTypeList[rng.Intn(len(txTypeList))]
-	var txData types.TxData
+	var tx *types.Transaction
 	switch txType {
 	case types.LegacyTxType:
-		txData = &types.LegacyTx{
-			Nonce:    rng.Uint64(),
-			GasPrice: new(big.Int).SetUint64(rng.Uint64()),
-			Gas:      gas,
-			To:       RandomTo(rng),
-			Value:    RandomETH(rng, 10),
-			Data:     RandomData(rng, rng.Intn(1000)),
-		}
+		tx = RandomLegacyTx(rng, signer)
 	case types.AccessListTxType:
-		txData = &types.AccessListTx{
-			ChainID:    signer.ChainID(),
-			Nonce:      rng.Uint64(),
-			GasPrice:   new(big.Int).SetUint64(rng.Uint64()),
-			Gas:        gas,
-			To:         RandomTo(rng),
-			Value:      RandomETH(rng, 10),
-			Data:       RandomData(rng, rng.Intn(1000)),
-			AccessList: nil,
-		}
+		tx = RandomAccessListTx(rng, signer)
 	case types.DynamicFeeTxType:
-		txData = &types.DynamicFeeTx{
-			ChainID:    signer.ChainID(),
-			Nonce:      rng.Uint64(),
-			GasTipCap:  tip,
-			GasFeeCap:  new(big.Int).Add(baseFee, tip),
-			Gas:        gas,
-			To:         RandomTo(rng),
-			Value:      RandomETH(rng, 10),
-			Data:       RandomData(rng, rng.Intn(1000)),
-			AccessList: nil,
-		}
+		tx = RandomDynamicFeeTxWithBaseFee(rng, baseFee, signer)
 	default:
 		panic("invalid tx type")
 	}
+	return tx
+}
+
+func RandomLegacyTx(rng *rand.Rand, signer types.Signer) *types.Transaction {
+	key := InsecureRandomKey(rng)
+	txData := &types.LegacyTx{
+		Nonce:    rng.Uint64(),
+		GasPrice: new(big.Int).SetUint64(rng.Uint64()),
+		Gas:      params.TxGas + uint64(rng.Int63n(2_000_000)),
+		To:       RandomTo(rng),
+		Value:    RandomETH(rng, 10),
+		Data:     RandomData(rng, rng.Intn(1000)),
+	}
+	tx, err := types.SignNewTx(key, signer, txData)
+	if err != nil {
+		panic(err)
+	}
+	return tx
+}
+
+func RandomAccessListTx(rng *rand.Rand, signer types.Signer) *types.Transaction {
+	key := InsecureRandomKey(rng)
+	txData := &types.AccessListTx{
+		ChainID:    signer.ChainID(),
+		Nonce:      rng.Uint64(),
+		GasPrice:   new(big.Int).SetUint64(rng.Uint64()),
+		Gas:        params.TxGas + uint64(rng.Int63n(2_000_000)),
+		To:         RandomTo(rng),
+		Value:      RandomETH(rng, 10),
+		Data:       RandomData(rng, rng.Intn(1000)),
+		AccessList: nil,
+	}
+	tx, err := types.SignNewTx(key, signer, txData)
+	if err != nil {
+		panic(err)
+	}
+	return tx
+}
+
+func RandomDynamicFeeTxWithBaseFee(rng *rand.Rand, baseFee *big.Int, signer types.Signer) *types.Transaction {
+	key := InsecureRandomKey(rng)
+	tip := big.NewInt(rng.Int63n(10 * params.GWei))
+	txData := &types.DynamicFeeTx{
+		ChainID:    signer.ChainID(),
+		Nonce:      rng.Uint64(),
+		GasTipCap:  tip,
+		GasFeeCap:  new(big.Int).Add(baseFee, tip),
+		Gas:        params.TxGas + uint64(rng.Int63n(2_000_000)),
+		To:         RandomTo(rng),
+		Value:      RandomETH(rng, 10),
+		Data:       RandomData(rng, rng.Intn(1000)),
+		AccessList: nil,
+	}
 	tx, err := types.SignNewTx(key, signer, txData)
 	if err != nil {
 		panic(err)
@@ -191,6 +214,11 @@ func RandomTx(rng *rand.Rand, baseFee *big.Int, signer types.Signer) *types.Tran
 	return tx
 }
 
+func RandomDynamicFeeTx(rng *rand.Rand, signer types.Signer) *types.Transaction {
+	baseFee := new(big.Int).SetUint64(rng.Uint64())
+	return RandomDynamicFeeTxWithBaseFee(rng, baseFee, signer)
+}
+
 func RandomReceipt(rng *rand.Rand, signer types.Signer, tx *types.Transaction, txIndex uint64, cumulativeGasUsed uint64) *types.Receipt {
 	gasUsed := params.TxGas + uint64(rng.Int63n(int64(tx.Gas()-params.TxGas+1)))
 	logs := make([]*types.Log, rng.Intn(10))