more channel builder tests :test_tube:

op-batcher/batcher/channel_builder.go

@@ -207,7 +207,7 @@ 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 alredy.
+// in this case marks the channel as full, if it wasn't full already.
 func (c *channelBuilder) checkTimeout(blockNum uint64) {
 	if !c.IsFull() && c.TimedOut(blockNum) {
 		c.setFullErr(c.timeoutReason)

op-batcher/batcher/channel_builder_test.go

@@ -2,9 +2,15 @@ package batcher
 
 import (
 	"bytes"
+	"math/big"
 	"testing"
 
+	"github.com/ethereum-optimism/optimism/op-node/eth"
 	"github.com/ethereum-optimism/optimism/op-node/rollup/derive"
+	"github.com/ethereum/go-ethereum/common"
+	"github.com/ethereum/go-ethereum/core/types"
+	"github.com/ethereum/go-ethereum/trie"
+
 	"github.com/stretchr/testify/suite"
 )
 
@@ -91,3 +97,148 @@ func (testSuite *ChannelBuilderTestSuite) TestBuilderWrongFramePanic() {
 	// If we get here, `PushFrame` did not panic as expected
 	testSuite.T().Errorf("did not panic")
 }
+
+func addNonsenseBlock(cb *channelBuilder) error {
+	lBlock := types.NewBlock(&types.Header{
+		BaseFee:    big.NewInt(10),
+		Difficulty: common.Big0,
+		Number:     big.NewInt(100),
+	}, nil, nil, nil, trie.NewStackTrie(nil))
+	l1InfoTx, err := derive.L1InfoDeposit(0, lBlock, eth.SystemConfig{}, false)
+	if err != nil {
+		return err
+	}
+	txs := []*types.Transaction{types.NewTx(l1InfoTx)}
+	a := types.NewBlock(&types.Header{
+		Number: big.NewInt(0),
+	}, txs, nil, nil, trie.NewStackTrie(nil))
+	err = cb.AddBlock(a)
+	return err
+}
+
+// TestOutputFrames tests the OutputFrames function
+func (testSuite *ChannelBuilderTestSuite) TestOutputFrames() {
+	// Lower the max frame size so that we can test
+	testSuite.channelConfig.MaxFrameSize = 2
+
+	// Construct the channel builder
+	cb, err := newChannelBuilder(testSuite.channelConfig)
+	testSuite.NoError(err)
+
+	testSuite.False(cb.IsFull())
+	testSuite.Equal(0, cb.NumFrames())
+
+	// Calling OutputFrames without having called [AddBlock]
+	// should return `nil`.
+	testSuite.Nil(cb.OutputFrames())
+
+	// There should be no ready bytes yet
+	readyBytes := cb.co.ReadyBytes()
+	testSuite.Equal(0, readyBytes)
+
+	// Let's add a block
+	err = addNonsenseBlock(cb)
+	testSuite.NoError(err)
+
+	// Check how many ready bytes
+	readyBytes = cb.co.ReadyBytes()
+	testSuite.Equal(2, readyBytes)
+
+	testSuite.Equal(0, cb.NumFrames())
+
+	// The channel should not be full
+	// but we want to output the frames for testing anyways
+	isFull := cb.IsFull()
+	testSuite.False(isFull)
+
+	// Since we manually set the max frame size to 2,
+	// we should be able to compress the two frames now
+	err = cb.OutputFrames()
+	testSuite.NoError(err)
+
+	// There should be one frame in the channel builder now
+	testSuite.Equal(1, cb.NumFrames())
+
+	// There should no longer be any ready bytes
+	readyBytes = cb.co.ReadyBytes()
+	testSuite.Equal(0, readyBytes)
+}
+
+// TestBuilderAddBlock tests the AddBlock function
+func (testSuite *ChannelBuilderTestSuite) TestBuilderAddBlock() {
+	// Lower the max frame size so that we can batch
+	testSuite.channelConfig.MaxFrameSize = 2
+
+	// Configure the Input Threshold params so we observe a full channel
+	// In reality, we only need the input bytes (74) below to be greater than
+	// or equal to the input threshold (3 * 2) / 1 = 6
+	testSuite.channelConfig.TargetFrameSize = 3
+	testSuite.channelConfig.TargetNumFrames = 2
+	testSuite.channelConfig.ApproxComprRatio = 1
+
+	// Construct the channel builder
+	cb, err := newChannelBuilder(testSuite.channelConfig)
+	testSuite.NoError(err)
+
+	// Add a nonsense block to the channel builder
+	err = addNonsenseBlock(cb)
+	testSuite.NoError(err)
+
+	// Check the fields reset in the AddBlock function
+	testSuite.Equal(74, cb.co.InputBytes())
+	testSuite.Equal(1, len(cb.blocks))
+	testSuite.Equal(0, len(cb.frames))
+	testSuite.True(cb.IsFull())
+
+	// Since the channel output is full, the next call to AddBlock
+	// should return the channel out full error
+	err = addNonsenseBlock(cb)
+	testSuite.ErrorIs(err, ErrInputTargetReached)
+}
+
+// TestBuilderReset tests the Reset function
+func (testSuite *ChannelBuilderTestSuite) TestBuilderReset() {
+	// Lower the max frame size so that we can batch
+	testSuite.channelConfig.MaxFrameSize = 2
+
+	cb, err := newChannelBuilder(testSuite.channelConfig)
+	testSuite.NoError(err)
+
+	// Add a nonsense block to the channel builder
+	err = addNonsenseBlock(cb)
+	testSuite.NoError(err)
+
+	// Check the fields reset in the Reset function
+	testSuite.Equal(1, len(cb.blocks))
+	testSuite.Equal(0, len(cb.frames))
+	// Timeout should be updated in the AddBlock internal call to `updateSwTimeout`
+	timeout := uint64(100) + cb.cfg.SeqWindowSize - cb.cfg.SubSafetyMargin
+	testSuite.Equal(timeout, cb.timeout)
+	testSuite.Nil(cb.fullErr)
+
+	// Output frames so we can set the channel builder frames
+	err = cb.OutputFrames()
+	testSuite.NoError(err)
+
+	// Add another block to increment the block count
+	err = addNonsenseBlock(cb)
+	testSuite.NoError(err)
+
+	// Check the fields reset in the Reset function
+	testSuite.Equal(2, len(cb.blocks))
+	testSuite.Equal(1, len(cb.frames))
+	testSuite.Equal(timeout, cb.timeout)
+	testSuite.Nil(cb.fullErr)
+
+	// Reset the channel builder
+	err = cb.Reset()
+	testSuite.NoError(err)
+
+	// Check the fields reset in the Reset function
+	testSuite.Equal(0, len(cb.blocks))
+	testSuite.Equal(0, len(cb.frames))
+	testSuite.Equal(uint64(0), cb.timeout)
+	testSuite.Nil(cb.fullErr)
+	testSuite.Equal(0, cb.co.InputBytes())
+	testSuite.Equal(0, cb.co.ReadyBytes())
+}