export ChannelBuilder so we can use it in external analysis scripts (#9784)

op-batcher/batcher/channel.go

@@ -12,7 +12,7 @@ import (
 	"github.com/ethereum/go-ethereum/log"
 )
 
-// channel is a lightweight wrapper around a channelBuilder which keeps track of pending
+// channel is a lightweight wrapper around a ChannelBuilder which keeps track of pending
 // and confirmed transactions for a single channel.
 type channel struct {
 	log  log.Logger
@@ -20,7 +20,7 @@ type channel struct {
 	cfg  ChannelConfig
 
 	// pending channel builder
-	channelBuilder *channelBuilder
+	channelBuilder *ChannelBuilder
 	// Set of unconfirmed txID -> frame data. For tx resubmission
 	pendingTransactions map[txID]txData
 	// Set of confirmed txID -> inclusion block. For determining if the channel is timed out
@@ -35,7 +35,7 @@ type channel struct {
 }
 
 func newChannel(log log.Logger, metr metrics.Metricer, cfg ChannelConfig, rollupCfg *rollup.Config) (*channel, error) {
-	cb, err := newChannelBuilder(cfg, *rollupCfg)
+	cb, err := NewChannelBuilder(cfg, *rollupCfg)
 	if err != nil {
 		return nil, fmt.Errorf("creating new channel: %w", err)
 	}

op-batcher/batcher/channel_builder.go

@@ -74,7 +74,7 @@ func (cc *ChannelConfig) Check() error {
 
 	// If the [MaxFrameSize] is set to 0, the channel builder
 	// will infinitely loop when trying to create frames in the
-	// [channelBuilder.OutputFrames] function.
+	// [ChannelBuilder.OutputFrames] function.
 	if cc.MaxFrameSize == 0 {
 		return errors.New("max frame size cannot be zero")
 	}
@@ -104,9 +104,9 @@ type frameData struct {
 	id   frameID
 }
 
-// channelBuilder uses a ChannelOut to create a channel with output frame
+// ChannelBuilder uses a ChannelOut to create a channel with output frame
 // size approximation.
-type channelBuilder struct {
+type ChannelBuilder struct {
 	cfg       ChannelConfig
 	rollupCfg rollup.Config
 
@@ -136,7 +136,7 @@ type channelBuilder struct {
 
 // newChannelBuilder creates a new channel builder or returns an error if the
 // channel out could not be created.
-func newChannelBuilder(cfg ChannelConfig, rollupCfg rollup.Config) (*channelBuilder, error) {
+func NewChannelBuilder(cfg ChannelConfig, rollupCfg rollup.Config) (*ChannelBuilder, error) {
 	c, err := cfg.CompressorConfig.NewCompressor()
 	if err != nil {
 		return nil, err
@@ -150,41 +150,41 @@ func newChannelBuilder(cfg ChannelConfig, rollupCfg rollup.Config) (*channelBuil
 		return nil, err
 	}
 
-	return &channelBuilder{
+	return &ChannelBuilder{
 		cfg:       cfg,
 		rollupCfg: rollupCfg,
 		co:        co,
 	}, nil
 }
 
-func (c *channelBuilder) ID() derive.ChannelID {
+func (c *ChannelBuilder) ID() derive.ChannelID {
 	return c.co.ID()
 }
 
 // InputBytes returns the total amount of input bytes added to the channel.
-func (c *channelBuilder) InputBytes() int {
+func (c *ChannelBuilder) InputBytes() int {
 	return c.co.InputBytes()
 }
 
 // ReadyBytes returns the amount of bytes ready in the compression pipeline to
 // output into a frame.
-func (c *channelBuilder) ReadyBytes() int {
+func (c *ChannelBuilder) ReadyBytes() int {
 	return c.co.ReadyBytes()
 }
 
-func (c *channelBuilder) OutputBytes() int {
+func (c *ChannelBuilder) OutputBytes() int {
 	return c.outputBytes
 }
 
 // Blocks returns a backup list of all blocks that were added to the channel. It
 // can be used in case the channel needs to be rebuilt.
-func (c *channelBuilder) Blocks() []*types.Block {
+func (c *ChannelBuilder) Blocks() []*types.Block {
 	return c.blocks
 }
 
 // Reset resets the internal state of the channel builder so that it can be
 // reused. Note that a new channel id is also generated by Reset.
-func (c *channelBuilder) Reset() error {
+func (c *ChannelBuilder) Reset() error {
 	c.blocks = c.blocks[:0]
 	c.frames = c.frames[:0]
 	c.timeout = 0
@@ -203,7 +203,7 @@ func (c *channelBuilder) Reset() error {
 // first transaction for subsequent use by the caller.
 //
 // Call OutputFrames() afterwards to create frames.
-func (c *channelBuilder) AddBlock(block *types.Block) (*derive.L1BlockInfo, error) {
+func (c *ChannelBuilder) AddBlock(block *types.Block) (*derive.L1BlockInfo, error) {
 	if c.IsFull() {
 		return nil, c.FullErr()
 	}
@@ -236,7 +236,7 @@ func (c *channelBuilder) AddBlock(block *types.Block) (*derive.L1BlockInfo, erro
 //
 // It ensures proper tracking of all possible timeouts (max channel duration,
 // close to consensus channel timeout, close to end of sequencing window).
-func (c *channelBuilder) RegisterL1Block(l1BlockNum uint64) {
+func (c *ChannelBuilder) RegisterL1Block(l1BlockNum uint64) {
 	c.updateDurationTimeout(l1BlockNum)
 	c.checkTimeout(l1BlockNum)
 }
@@ -244,7 +244,7 @@ func (c *channelBuilder) RegisterL1Block(l1BlockNum uint64) {
 // FramePublished should be called whenever a frame of this channel got
 // published with the L1-block number of the block that the frame got included
 // in.
-func (c *channelBuilder) FramePublished(l1BlockNum uint64) {
+func (c *ChannelBuilder) FramePublished(l1BlockNum uint64) {
 	timeout := l1BlockNum + c.cfg.ChannelTimeout - c.cfg.SubSafetyMargin
 	c.updateTimeout(timeout, ErrChannelTimeoutClose)
 }
@@ -254,7 +254,7 @@ func (c *channelBuilder) FramePublished(l1BlockNum uint64) {
 // forward if the derived timeout is earlier than the currently set timeout.
 //
 // It does nothing if the max channel duration is set to 0.
-func (c *channelBuilder) updateDurationTimeout(l1BlockNum uint64) {
+func (c *ChannelBuilder) updateDurationTimeout(l1BlockNum uint64) {
 	if c.cfg.MaxChannelDuration == 0 {
 		return
 	}
@@ -266,7 +266,7 @@ func (c *channelBuilder) updateDurationTimeout(l1BlockNum uint64) {
 // derived from the batch's origin L1 block. The timeout is only moved forward
 // if the derived sequencer window timeout is earlier than the currently set
 // timeout.
-func (c *channelBuilder) updateSwTimeout(batch *derive.SingularBatch) {
+func (c *ChannelBuilder) updateSwTimeout(batch *derive.SingularBatch) {
 	timeout := uint64(batch.EpochNum) + c.cfg.SeqWindowSize - c.cfg.SubSafetyMargin
 	c.updateTimeout(timeout, ErrSeqWindowClose)
 }
@@ -276,7 +276,7 @@ func (c *channelBuilder) updateSwTimeout(batch *derive.SingularBatch) {
 //
 // If the timeout is updated, the provided reason will be set as the channel
 // full error reason in case the timeout is hit in the future.
-func (c *channelBuilder) updateTimeout(timeoutBlockNum uint64, reason error) {
+func (c *ChannelBuilder) updateTimeout(timeoutBlockNum uint64, reason error) {
 	if c.timeout == 0 || c.timeout > timeoutBlockNum {
 		c.timeout = timeoutBlockNum
 		c.timeoutReason = reason
@@ -285,7 +285,7 @@ func (c *channelBuilder) updateTimeout(timeoutBlockNum uint64, reason error) {
 
 // checkTimeout checks if the channel is timed out at the given block number and
 // in this case marks the channel as full, if it wasn't full already.
-func (c *channelBuilder) checkTimeout(blockNum uint64) {
+func (c *ChannelBuilder) checkTimeout(blockNum uint64) {
 	if !c.IsFull() && c.TimedOut(blockNum) {
 		c.setFullErr(c.timeoutReason)
 	}
@@ -293,13 +293,13 @@ func (c *channelBuilder) checkTimeout(blockNum uint64) {
 
 // TimedOut returns whether the passed block number is after the timeout block
 // number. If no block timeout is set yet, it returns false.
-func (c *channelBuilder) TimedOut(blockNum uint64) bool {
+func (c *ChannelBuilder) TimedOut(blockNum uint64) bool {
 	return c.timeout != 0 && blockNum >= c.timeout
 }
 
 // IsFull returns whether the channel is full.
 // FullErr returns the reason for the channel being full.
-func (c *channelBuilder) IsFull() bool {
+func (c *ChannelBuilder) IsFull() bool {
 	return c.fullErr != nil
 }
 
@@ -317,11 +317,11 @@ func (c *channelBuilder) IsFull() bool {
 //   - ErrChannelTimeoutClose if the consensus channel timeout got too close,
 //   - ErrSeqWindowClose if the end of the sequencer window got too close,
 //   - ErrTerminated if the channel was explicitly terminated.
-func (c *channelBuilder) FullErr() error {
+func (c *ChannelBuilder) FullErr() error {
 	return c.fullErr
 }
 
-func (c *channelBuilder) setFullErr(err error) {
+func (c *ChannelBuilder) setFullErr(err error) {
 	c.fullErr = &ChannelFullError{Err: err}
 }
 
@@ -333,7 +333,7 @@ func (c *channelBuilder) setFullErr(err error) {
 // pull readily available frames from the compression output.
 // If it is full, the channel is closed and all remaining
 // frames will be created, possibly with a small leftover frame.
-func (c *channelBuilder) OutputFrames() error {
+func (c *ChannelBuilder) OutputFrames() error {
 	if c.IsFull() {
 		err := c.closeAndOutputAllFrames()
 		if err != nil {
@@ -349,7 +349,7 @@ func (c *channelBuilder) OutputFrames() error {
 //
 // This is part of an optimization to already generate frames and send them off
 // as txs while still collecting blocks in the channel builder.
-func (c *channelBuilder) outputReadyFrames() error {
+func (c *ChannelBuilder) outputReadyFrames() error {
 	// TODO: Decide whether we want to fill frames to max size and use target
 	// only for estimation, or use target size.
 	for c.co.ReadyBytes() >= int(c.cfg.MaxFrameSize) {
@@ -362,7 +362,7 @@ func (c *channelBuilder) outputReadyFrames() error {
 	return nil
 }
 
-func (c *channelBuilder) closeAndOutputAllFrames() error {
+func (c *ChannelBuilder) closeAndOutputAllFrames() error {
 	if err := c.co.Close(); err != nil {
 		return fmt.Errorf("closing channel out: %w", err)
 	}
@@ -379,7 +379,7 @@ func (c *channelBuilder) closeAndOutputAllFrames() error {
 // outputFrame creates one new frame and adds it to the frames queue.
 // Note that compressed output data must be available on the underlying
 // ChannelOut, or an empty frame will be produced.
-func (c *channelBuilder) outputFrame() error {
+func (c *ChannelBuilder) outputFrame() error {
 	var buf bytes.Buffer
 	fn, err := c.co.OutputFrame(&buf, c.cfg.MaxFrameSize)
 	if err != io.EOF && err != nil {
@@ -409,7 +409,7 @@ func (c *channelBuilder) outputFrame() error {
 
 // Close immediately marks the channel as full with an ErrTerminated
 // if the channel is not already full.
-func (c *channelBuilder) Close() {
+func (c *ChannelBuilder) Close() {
 	if !c.IsFull() {
 		c.setFullErr(ErrTerminated)
 	}
@@ -417,7 +417,7 @@ func (c *channelBuilder) Close() {
 
 // TotalFrames returns the total number of frames that were created in this channel so far.
 // It does not decrease when the frames queue is being emptied.
-func (c *channelBuilder) TotalFrames() int {
+func (c *ChannelBuilder) TotalFrames() int {
 	return c.numFrames
 }
 
@@ -426,20 +426,20 @@ func (c *channelBuilder) TotalFrames() int {
 //
 // Call OutputFrames before to create new frames from the channel out
 // compression pipeline.
-func (c *channelBuilder) HasFrame() bool {
+func (c *ChannelBuilder) HasFrame() bool {
 	return len(c.frames) > 0
 }
 
 // PendingFrames returns the number of pending frames in the frames queue.
 // It is larger zero iff HasFrames() returns true.
-func (c *channelBuilder) PendingFrames() int {
+func (c *ChannelBuilder) PendingFrames() int {
 	return len(c.frames)
 }
 
 // NextFrame returns the next available frame.
 // HasFrame must be called prior to check if there's a next frame available.
 // Panics if called when there's no next frame.
-func (c *channelBuilder) NextFrame() frameData {
+func (c *ChannelBuilder) NextFrame() frameData {
 	if len(c.frames) == 0 {
 		panic("no next frame")
 	}
@@ -451,7 +451,7 @@ func (c *channelBuilder) NextFrame() frameData {
 
 // PushFrame adds the frame back to the internal frames queue. Panics if not of
 // the same channel.
-func (c *channelBuilder) PushFrame(frame frameData) {
+func (c *ChannelBuilder) PushFrame(frame frameData) {
 	if frame.id.chID != c.ID() {
 		panic("wrong channel")
 	}

op-batcher/batcher/channel_builder_test.go

@@ -116,8 +116,8 @@ func FuzzChannelConfig_CheckTimeout(f *testing.F) {
 }
 
 // addMiniBlock adds a minimal valid L2 block to the channel builder using the
-// channelBuilder.AddBlock method.
-func addMiniBlock(cb *channelBuilder) error {
+// ChannelBuilder.AddBlock method.
+func addMiniBlock(cb *ChannelBuilder) error {
 	a := newMiniL2Block(0)
 	_, err := cb.AddBlock(a)
 	return err
@@ -163,7 +163,7 @@ func newMiniL2BlockWithNumberParent(numTx int, number *big.Int, parent common.Ha
 
 // addTooManyBlocks adds blocks to the channel until it hits an error,
 // which is presumably ErrTooManyRLPBytes.
-func addTooManyBlocks(cb *channelBuilder) error {
+func addTooManyBlocks(cb *ChannelBuilder) error {
 	rng := rand.New(rand.NewSource(1234))
 	for i := 0; i < 10_000; i++ {
 		block := dtest.RandomL2BlockWithChainId(rng, 1000, defaultTestRollupConfig.L2ChainID)
@@ -185,7 +185,7 @@ func FuzzDurationTimeoutZeroMaxChannelDuration(f *testing.F) {
 	f.Fuzz(func(t *testing.T, l1BlockNum uint64) {
 		channelConfig := defaultTestChannelConfig
 		channelConfig.MaxChannelDuration = 0
-		cb, err := newChannelBuilder(channelConfig, defaultTestRollupConfig)
+		cb, err := NewChannelBuilder(channelConfig, defaultTestRollupConfig)
 		require.NoError(t, err)
 		cb.timeout = 0
 		cb.updateDurationTimeout(l1BlockNum)
@@ -208,7 +208,7 @@ func FuzzChannelBuilder_DurationZero(f *testing.F) {
 		// Create the channel builder
 		channelConfig := defaultTestChannelConfig
 		channelConfig.MaxChannelDuration = maxChannelDuration
-		cb, err := newChannelBuilder(channelConfig, defaultTestRollupConfig)
+		cb, err := NewChannelBuilder(channelConfig, defaultTestRollupConfig)
 		require.NoError(t, err)
 
 		// Whenever the timeout is set to 0, the channel builder should have a duration timeout
@@ -235,7 +235,7 @@ func FuzzDurationTimeoutMaxChannelDuration(f *testing.F) {
 		// Create the channel builder
 		channelConfig := defaultTestChannelConfig
 		channelConfig.MaxChannelDuration = maxChannelDuration
-		cb, err := newChannelBuilder(channelConfig, defaultTestRollupConfig)
+		cb, err := NewChannelBuilder(channelConfig, defaultTestRollupConfig)
 		require.NoError(t, err)
 
 		// Whenever the timeout is greater than the l1BlockNum,
@@ -269,7 +269,7 @@ func FuzzChannelCloseTimeout(f *testing.F) {
 		channelConfig := defaultTestChannelConfig
 		channelConfig.ChannelTimeout = channelTimeout
 		channelConfig.SubSafetyMargin = subSafetyMargin
-		cb, err := newChannelBuilder(channelConfig, defaultTestRollupConfig)
+		cb, err := NewChannelBuilder(channelConfig, defaultTestRollupConfig)
 		require.NoError(t, err)
 
 		// Check the timeout
@@ -297,7 +297,7 @@ func FuzzChannelZeroCloseTimeout(f *testing.F) {
 		channelConfig := defaultTestChannelConfig
 		channelConfig.ChannelTimeout = channelTimeout
 		channelConfig.SubSafetyMargin = subSafetyMargin
-		cb, err := newChannelBuilder(channelConfig, defaultTestRollupConfig)
+		cb, err := NewChannelBuilder(channelConfig, defaultTestRollupConfig)
 		require.NoError(t, err)
 
 		// Check the timeout
@@ -324,7 +324,7 @@ func FuzzSeqWindowClose(f *testing.F) {
 		channelConfig := defaultTestChannelConfig
 		channelConfig.SeqWindowSize = seqWindowSize
 		channelConfig.SubSafetyMargin = subSafetyMargin
-		cb, err := newChannelBuilder(channelConfig, defaultTestRollupConfig)
+		cb, err := NewChannelBuilder(channelConfig, defaultTestRollupConfig)
 		require.NoError(t, err)
 
 		// Check the timeout
@@ -352,7 +352,7 @@ func FuzzSeqWindowZeroTimeoutClose(f *testing.F) {
 		channelConfig := defaultTestChannelConfig
 		channelConfig.SeqWindowSize = seqWindowSize
 		channelConfig.SubSafetyMargin = subSafetyMargin
-		cb, err := newChannelBuilder(channelConfig, defaultTestRollupConfig)
+		cb, err := NewChannelBuilder(channelConfig, defaultTestRollupConfig)
 		require.NoError(t, err)
 
 		// Check the timeout
@@ -399,10 +399,10 @@ func TestChannelBuilder_NextFrame(t *testing.T) {
 	channelConfig := defaultTestChannelConfig
 
 	// Create a new channel builder
-	cb, err := newChannelBuilder(channelConfig, defaultTestRollupConfig)
+	cb, err := NewChannelBuilder(channelConfig, defaultTestRollupConfig)
 	require.NoError(t, err)
 
-	// Mock the internals of `channelBuilder.outputFrame`
+	// Mock the internals of `ChannelBuilder.outputFrame`
 	// to construct a single frame
 	co := cb.co
 	var buf bytes.Buffer
@@ -439,10 +439,10 @@ func TestChannelBuilder_OutputWrongFramePanic(t *testing.T) {
 	channelConfig := defaultTestChannelConfig
 
 	// Construct a channel builder
-	cb, err := newChannelBuilder(channelConfig, defaultTestRollupConfig)
+	cb, err := NewChannelBuilder(channelConfig, defaultTestRollupConfig)
 	require.NoError(t, err)
 
-	// Mock the internals of `channelBuilder.outputFrame`
+	// Mock the internals of `ChannelBuilder.outputFrame`
 	// to construct a single frame
 	c, err := channelConfig.CompressorConfig.NewCompressor()
 	require.NoError(t, err)
@@ -472,7 +472,7 @@ func TestChannelBuilder_OutputFramesWorks(t *testing.T) {
 	channelConfig.MaxFrameSize = 24
 
 	// Construct the channel builder
-	cb, err := newChannelBuilder(channelConfig, defaultTestRollupConfig)
+	cb, err := NewChannelBuilder(channelConfig, defaultTestRollupConfig)
 	require.NoError(t, err)
 	require.False(t, cb.IsFull())
 	require.Equal(t, 0, cb.PendingFrames())
@@ -515,7 +515,7 @@ func TestChannelBuilder_OutputFramesWorks_SpanBatch(t *testing.T) {
 	channelConfig.BatchType = derive.SpanBatchType
 
 	// Construct the channel builder
-	cb, err := newChannelBuilder(channelConfig, defaultTestRollupConfig)
+	cb, err := NewChannelBuilder(channelConfig, defaultTestRollupConfig)
 	require.NoError(t, err)
 	require.False(t, cb.IsFull())
 	require.Equal(t, 0, cb.PendingFrames())
@@ -557,7 +557,7 @@ func TestChannelBuilder_OutputFramesWorks_SpanBatch(t *testing.T) {
 	require.LessOrEqual(t, len(cb.frames[len(cb.frames)-1].data), int(channelConfig.MaxFrameSize))
 }
 
-// ChannelBuilder_MaxRLPBytesPerChannel tests the [channelBuilder.OutputFrames]
+// ChannelBuilder_MaxRLPBytesPerChannel tests the [ChannelBuilder.OutputFrames]
 // function errors when the max RLP bytes per channel is reached.
 func ChannelBuilder_MaxRLPBytesPerChannel(t *testing.T, batchType uint) {
 	t.Parallel()
@@ -568,7 +568,7 @@ func ChannelBuilder_MaxRLPBytesPerChannel(t *testing.T, batchType uint) {
 	channelConfig.BatchType = batchType
 
 	// Construct the channel builder
-	cb, err := newChannelBuilder(channelConfig, defaultTestRollupConfig)
+	cb, err := NewChannelBuilder(channelConfig, defaultTestRollupConfig)
 	require.NoError(t, err)
 
 	// Add a block that overflows the [ChannelOut]
@@ -589,9 +589,9 @@ func ChannelBuilder_OutputFramesMaxFrameIndex(t *testing.T, batchType uint) {
 	rng := rand.New(rand.NewSource(123))
 
 	// Continuously add blocks until the max frame index is reached
-	// This should cause the [channelBuilder.OutputFrames] function
+	// This should cause the [ChannelBuilder.OutputFrames] function
 	// to error
-	cb, err := newChannelBuilder(channelConfig, defaultTestRollupConfig)
+	cb, err := NewChannelBuilder(channelConfig, defaultTestRollupConfig)
 	require.NoError(t, err)
 	require.False(t, cb.IsFull())
 	require.Equal(t, 0, cb.PendingFrames())
@@ -624,7 +624,7 @@ func ChannelBuilder_AddBlock(t *testing.T, batchType uint) {
 	channelConfig.CompressorConfig.ApproxComprRatio = 1
 
 	// Construct the channel builder
-	cb, err := newChannelBuilder(channelConfig, defaultTestRollupConfig)
+	cb, err := NewChannelBuilder(channelConfig, defaultTestRollupConfig)
 	require.NoError(t, err)
 
 	// Add a nonsense block to the channel builder
@@ -657,7 +657,7 @@ func ChannelBuilder_Reset(t *testing.T, batchType uint) {
 	channelConfig.CompressorConfig.TargetFrameSize = 24
 	channelConfig.CompressorConfig.ApproxComprRatio = 1
 
-	cb, err := newChannelBuilder(channelConfig, defaultTestRollupConfig)
+	cb, err := NewChannelBuilder(channelConfig, defaultTestRollupConfig)
 	require.NoError(t, err)
 
 	// Add a nonsense block to the channel builder
@@ -698,7 +698,7 @@ func TestBuilderRegisterL1Block(t *testing.T) {
 	channelConfig := defaultTestChannelConfig
 
 	// Construct the channel builder
-	cb, err := newChannelBuilder(channelConfig, defaultTestRollupConfig)
+	cb, err := NewChannelBuilder(channelConfig, defaultTestRollupConfig)
 	require.NoError(t, err)
 
 	// Assert params modified in RegisterL1Block
@@ -721,7 +721,7 @@ func TestBuilderRegisterL1BlockZeroMaxChannelDuration(t *testing.T) {
 	channelConfig.MaxChannelDuration = 0
 
 	// Construct the channel builder
-	cb, err := newChannelBuilder(channelConfig, defaultTestRollupConfig)
+	cb, err := NewChannelBuilder(channelConfig, defaultTestRollupConfig)
 	require.NoError(t, err)
 
 	// Assert params modified in RegisterL1Block
@@ -742,7 +742,7 @@ func TestFramePublished(t *testing.T) {
 	channelConfig := defaultTestChannelConfig
 
 	// Construct the channel builder
-	cb, err := newChannelBuilder(channelConfig, defaultTestRollupConfig)
+	cb, err := NewChannelBuilder(channelConfig, defaultTestRollupConfig)
 	require.NoError(t, err)
 
 	// Let's say the block number is fed in as 100
@@ -768,7 +768,7 @@ func ChannelBuilder_PendingFrames_TotalFrames(t *testing.T, batchType uint) {
 	cfg.CompressorConfig.TargetNumFrames = tnf
 	cfg.CompressorConfig.Kind = "shadow"
 	cfg.BatchType = batchType
-	cb, err := newChannelBuilder(cfg, defaultTestRollupConfig)
+	cb, err := NewChannelBuilder(cfg, defaultTestRollupConfig)
 	require.NoError(err)
 
 	// initial builder should be empty
@@ -812,7 +812,7 @@ func ChannelBuilder_InputBytes(t *testing.T, batchType uint) {
 		chainId := big.NewInt(1234)
 		spanBatchBuilder = derive.NewSpanBatchBuilder(uint64(0), chainId)
 	}
-	cb, err := newChannelBuilder(cfg, defaultTestRollupConfig)
+	cb, err := NewChannelBuilder(cfg, defaultTestRollupConfig)
 	require.NoError(err)
 
 	require.Zero(cb.InputBytes())
@@ -848,8 +848,8 @@ func ChannelBuilder_OutputBytes(t *testing.T, batchType uint) {
 	cfg.CompressorConfig.TargetNumFrames = 16
 	cfg.CompressorConfig.ApproxComprRatio = 1.0
 	cfg.BatchType = batchType
-	cb, err := newChannelBuilder(cfg, defaultTestRollupConfig)
-	require.NoError(err, "newChannelBuilder")
+	cb, err := NewChannelBuilder(cfg, defaultTestRollupConfig)
+	require.NoError(err, "NewChannelBuilder")
 
 	require.Zero(cb.OutputBytes())