From c9c3502fb616e4fe2e71ec794ce0fac34e996010 Mon Sep 17 00:00:00 2001
From: Sebastian Stammler <seb@oplabs.co>
Date: Sat, 11 Mar 2023 21:23:17 +0100
Subject: [PATCH] op-batcher: Test requeuing of transactions

Regression test for #4937
---
 op-batcher/batcher/channel_manager_test.go | 49 ++++++++++++++++++++--
 1 file changed, 46 insertions(+), 3 deletions(-)

diff --git a/op-batcher/batcher/channel_manager_test.go b/op-batcher/batcher/channel_manager_test.go
index 2ddbcede3de7c..36f06dc073ff9 100644
--- a/op-batcher/batcher/channel_manager_test.go
+++ b/op-batcher/batcher/channel_manager_test.go
@@ -3,12 +3,15 @@ package batcher_test
 import (
 	"io"
 	"math/big"
+	"math/rand"
 	"testing"
+	"time"
 
 	"github.com/ethereum-optimism/optimism/op-batcher/batcher"
 	"github.com/ethereum-optimism/optimism/op-node/eth"
 	"github.com/ethereum-optimism/optimism/op-node/rollup/derive"
 	"github.com/ethereum-optimism/optimism/op-node/testlog"
+	"github.com/ethereum-optimism/optimism/op-node/testutils"
 	"github.com/ethereum/go-ethereum/common"
 	"github.com/ethereum/go-ethereum/core/types"
 	"github.com/ethereum/go-ethereum/log"
@@ -54,15 +57,15 @@ func TestChannelManagerReturnsErrReorgWhenDrained(t *testing.T) {
 	log := testlog.Logger(t, log.LvlCrit)
 	m := batcher.NewChannelManager(log, batcher.ChannelConfig{
 		TargetFrameSize:  0,
-		MaxFrameSize:     100,
+		MaxFrameSize:     120_000,
 		ApproxComprRatio: 1.0,
 	})
-	lBlock := types.NewBlock(&types.Header{
+	l1Block := 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)
+	l1InfoTx, err := derive.L1InfoDeposit(0, l1Block, eth.SystemConfig{}, false)
 	require.NoError(t, err)
 	txs := []*types.Transaction{types.NewTx(l1InfoTx)}
 
@@ -81,6 +84,46 @@ func TestChannelManagerReturnsErrReorgWhenDrained(t *testing.T) {
 	require.NoError(t, err)
 	_, err = m.TxData(eth.BlockID{})
 	require.ErrorIs(t, err, io.EOF)
+
 	err = m.AddL2Block(x)
 	require.ErrorIs(t, err, batcher.ErrReorg)
 }
+
+func TestChannelManager_TxResend(t *testing.T) {
+	require := require.New(t)
+	rng := rand.New(rand.NewSource(time.Now().UnixNano()))
+	log := testlog.Logger(t, log.LvlError)
+	m := batcher.NewChannelManager(log, batcher.ChannelConfig{
+		TargetFrameSize:  0,
+		MaxFrameSize:     120_000,
+		ApproxComprRatio: 1.0,
+	})
+
+	a, _ := testutils.RandomL2Block(rng, 4)
+
+	err := m.AddL2Block(a)
+	require.NoError(err)
+
+	txdata0, err := m.TxData(eth.BlockID{})
+	require.NoError(err)
+	txdata0bytes := txdata0.Bytes()
+	data0 := make([]byte, len(txdata0bytes))
+	// make sure we have a clone for later comparison
+	copy(data0, txdata0bytes)
+
+	// ensure channel is drained
+	_, err = m.TxData(eth.BlockID{})
+	require.ErrorIs(err, io.EOF)
+
+	// requeue frame
+	m.TxFailed(txdata0.ID())
+
+	txdata1, err := m.TxData(eth.BlockID{})
+	require.NoError(err)
+
+	data1 := txdata1.Bytes()
+	require.Equal(data1, data0)
+	fs, err := derive.ParseFrames(data1)
+	require.NoError(err)
+	require.Len(fs, 1)
+}