core/overlay: add unit test

Author: rjl493456442

core/overlay/state_transition.go

@@ -27,10 +27,10 @@ import (
 // tracking which parts of the legacy MPT-based state have already been
 // migrated to the Verkle-based state.
 type TransitionState struct {
-	// CurrentAccountHash is the address of the next account to be migrated
+	// CurrentAccountHash is the hash of the next account to be migrated
 	// from the MPT state to the Verkle state. Null means nothing has been
 	// migrated yet.
-	CurrentAccountAddress *common.Address
+	CurrentAccountHash common.Hash
 
 	// CurrentSlotHash is the hash of the next storage slot (within the
 	// current account) to be migrated from the MPT state to the Verkle state.
@@ -74,22 +74,6 @@ func (ts *TransitionState) Transitioned() bool {
 	return ts != nil && ts.Ended
 }
 
-// Copy returns a deep copy of the TransitionState object.
-func (ts *TransitionState) Copy() *TransitionState {
-	ret := &TransitionState{
-		Started:               ts.Started,
-		Ended:                 ts.Ended,
-		CurrentSlotHash:       ts.CurrentSlotHash,
-		CurrentPreimageOffset: ts.CurrentPreimageOffset,
-		StorageProcessed:      ts.StorageProcessed,
-	}
-	if ts.CurrentAccountAddress != nil {
-		ret.CurrentAccountAddress = &common.Address{}
-		copy(ret.CurrentAccountAddress[:], ts.CurrentAccountAddress[:])
-	}
-	return ret
-}
-
 // LoadTransitionState retrieves the Verkle transition state associated with
 // the given state root hash from the database.
 func LoadTransitionState(db ethdb.KeyValueReader, root common.Hash) (*TransitionState, error) {

core/overlay/state_transition_test.go

@@ -0,0 +1,48 @@
+// Copyright 2025 The go-ethereum Authors
+// This file is part of the go-ethereum library.
+//
+// The go-ethereum library is free software: you can redistribute it and/or modify
+// it under the terms of the GNU Lesser General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// The go-ethereum library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+// GNU Lesser General Public License for more details.
+//
+// You should have received a copy of the GNU Lesser General Public License
+// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
+
+package overlay
+
+import (
+	"reflect"
+	"testing"
+
+	"github.com/davecgh/go-spew/spew"
+	"github.com/ethereum/go-ethereum/common"
+	"github.com/ethereum/go-ethereum/core/rawdb"
+	"github.com/ethereum/go-ethereum/internal/testrand"
+)
+
+func TestLoadStoreTransitionState(t *testing.T) {
+	has := &TransitionState{
+		CurrentAccountHash: testrand.Hash(),
+		CurrentSlotHash:    testrand.Hash(),
+		BaseRoot:           testrand.Hash(),
+	}
+	db := rawdb.NewMemoryDatabase()
+	if err := StoreTransitionState(db, common.Hash{0x1}, has); err != nil {
+		t.Fatal(err)
+	}
+	got, err := LoadTransitionState(db, common.Hash{0x1})
+	if err != nil {
+		t.Fatal(err)
+	}
+	if !reflect.DeepEqual(got, has) {
+		spew.Dump(got)
+		spew.Dump(has)
+		t.Fatalf("Unexpected transition state")
+	}
+}