From bca071a1ddf151ebb712cd01a28557b09d333d9d Mon Sep 17 00:00:00 2001
From: lightclient <lightclient@protonmail.com>
Date: Fri, 19 Sep 2025 07:35:31 -0600
Subject: [PATCH] core/txpool/blobpool: add test for migration of existing txs
 at osaka boundary

---
 core/txpool/blobpool/blobpool.go      |  7 +-
 core/txpool/blobpool/blobpool_test.go | 94 +++++++++++++++++++++++++++
 2 files changed, 100 insertions(+), 1 deletion(-)

diff --git a/core/txpool/blobpool/blobpool.go b/core/txpool/blobpool/blobpool.go
index 423d2593aa..9e4c1eaa48 100644
--- a/core/txpool/blobpool/blobpool.go
+++ b/core/txpool/blobpool/blobpool.go
@@ -339,7 +339,9 @@ type BlobPool struct {
 
 	signer types.Signer     // Transaction signer to use for sender recovery
 	chain  BlockChain       // Chain object to access the state through
-	cQueue *conversionQueue // The queue for performing legacy sidecar conversion
+	cQueue *conversionQueue // The queue for performing legacy sidecar conversion (TODO: remove after Osaka)
+
+	sidecarMigrationDoneCh chan struct{} // Channel for signaling when all txs at the boundary have been converted (TODO: remove after Osaka)
 
 	head   atomic.Pointer[types.Header] // Current head of the chain
 	state  *state.StateDB               // Current state at the head of the chain
@@ -946,6 +948,9 @@ func (p *BlobPool) Reset(oldHead, newHead *types.Header) {
 					}
 				}
 			}
+			if p.sidecarMigrationDoneCh != nil {
+				close(p.sidecarMigrationDoneCh)
+			}
 			log.Info("Completed the blob transaction conversion", "discarded", fail, "injected", success, "elapsed", common.PrettyDuration(time.Since(start)))
 		}()
 	}
diff --git a/core/txpool/blobpool/blobpool_test.go b/core/txpool/blobpool/blobpool_test.go
index 75a87940bd..b717d9c5e2 100644
--- a/core/txpool/blobpool/blobpool_test.go
+++ b/core/txpool/blobpool/blobpool_test.go
@@ -2098,6 +2098,98 @@ func TestGetBlobs(t *testing.T) {
 	pool.Close()
 }
 
+// TestSidecarConversion will verify that after the Osaka fork, all legacy
+// sidecars in the pool are successfully convert to v1 sidecars.
+func TestSidecarConversion(t *testing.T) {
+	// log.SetDefault(log.NewLogger(log.NewTerminalHandlerWithLevel(os.Stderr, log.LevelDebug, true)))
+
+	// Create a temporary folder for the persistent backend
+	storage := t.TempDir()
+	os.MkdirAll(filepath.Join(storage, pendingTransactionStore), 0700)
+
+	var (
+		count      = 10
+		keys       = make([]*ecdsa.PrivateKey, count)
+		addrs      = make([]common.Address, count)
+		statedb, _ = state.New(types.EmptyRootHash, state.NewDatabaseForTesting())
+	)
+	for i := 0; i < count; i++ {
+		keys[i], _ = crypto.GenerateKey()
+		addrs[i] = crypto.PubkeyToAddress(keys[i].PublicKey)
+		statedb.AddBalance(addrs[i], uint256.NewInt(1_000_000_000), tracing.BalanceChangeUnspecified)
+	}
+	statedb.Commit(0, true, false)
+
+	config := &params.ChainConfig{
+		ChainID:            big.NewInt(1),
+		LondonBlock:        big.NewInt(0),
+		BerlinBlock:        big.NewInt(0),
+		CancunTime:         newUint64(0),
+		PragueTime:         newUint64(0),
+		OsakaTime:          newUint64(1),
+		BlobScheduleConfig: params.DefaultBlobSchedule,
+	}
+	chain := &testBlockChain{
+		config:  config,
+		basefee: uint256.NewInt(1050),
+		blobfee: uint256.NewInt(105),
+		statedb: statedb,
+	}
+
+	before := chain.CurrentBlock()
+	before.Time = 0
+	after := chain.CurrentBlock()
+	after.Time = 1
+
+	pool := New(Config{Datadir: storage}, chain, nil)
+	if err := pool.Init(1, before, newReserver()); err != nil {
+		t.Fatalf("failed to create blob pool: %v", err)
+	}
+
+	for i, key := range keys {
+		tx := makeMultiBlobTx(0, 1, 1000, 100, 2, 0, key, types.BlobSidecarVersion0)
+		if errs := pool.Add([]*types.Transaction{tx}, true); errs[0] != nil {
+			t.Errorf("failed to insert blob tx from %s: %s", addrs[i], errs[0])
+		}
+	}
+
+	// Should kick off migration.
+	pool.sidecarMigrationDoneCh = make(chan struct{})
+	pool.Reset(before, after)
+	<-pool.sidecarMigrationDoneCh
+
+	// Verify all transactions in the pool were converted and verify the
+	// subsequent cell proofs.
+	pending, _ := pool.Stats()
+	if pending != count {
+		t.Errorf("expected pending count to match initial tx count: pending=%d, expected=%d", pending, count)
+	}
+	for addr, acc := range pool.index {
+		for _, m := range acc {
+			if m.version != types.BlobSidecarVersion1 {
+				t.Errorf("expected sidecar to have been converted: from %s, hash %s", addr, m.hash)
+			}
+			tx := pool.Get(m.hash)
+			if tx == nil {
+				t.Errorf("failed to get tx by hash: %s", m.hash)
+			}
+			sc := tx.BlobTxSidecar()
+			if err := kzg4844.VerifyCellProofs(sc.Blobs, sc.Commitments, sc.Proofs); err != nil {
+				t.Errorf("failed to verify cell proofs for tx %s after conversion: %s", m.hash, err)
+			}
+		}
+	}
+
+	// Verify all the calculated pool internals. Interestingly, this is **not**
+	// a duplication of the above checks, this actually validates the verifier
+	// using the above already hard coded checks.
+	//
+	// Do not remove this, nor alter the above to be generic.
+	verifyPoolInternals(t, pool)
+
+	pool.Close()
+}
+
 // fakeBilly is a billy.Database implementation which just drops data on the floor.
 type fakeBilly struct {
 	billy.Database
@@ -2180,3 +2272,5 @@ func benchmarkPoolPending(b *testing.B, datacap uint64) {
 		}
 	}
 }
+
+func newUint64(val uint64) *uint64 { return &val }