implement some heretofore unimplemented iterator methods

trie/verkle_iterator.go

@@ -142,7 +142,18 @@ func (it *verkleNodeIterator) Parent() common.Hash {
 // Callers must not retain references to the return value after calling Next.
 // For leaf nodes, the last element of the path is the 'terminator symbol' 0x10.
 func (it *verkleNodeIterator) Path() []byte {
-	panic("not completely implemented")
+	if it.Leaf() {
+		return it.LeafKey()
+	}
+	var path []byte
+	for i, state := range it.stack {
+		// skip the last byte
+		if i <= len(it.stack)-1 {
+			break
+		}
+		path = append(path, byte(state.Index))
+	}
+	return path
 }
 
 func (it *verkleNodeIterator) NodeBlob() []byte {
@@ -204,5 +215,5 @@ func (it *verkleNodeIterator) LeafProof() [][]byte {
 // making trie.Database an interface and wrapping at that level. It's a huge
 // refactor, but it could be worth it if another occurrence arises.
 func (it *verkleNodeIterator) AddResolver(ethdb.KeyValueReader) {
-	panic("not completely implemented")
+	// Not implemented, but should not panic
 }

trie/verkle_iterator_test.go

@@ -0,0 +1,65 @@
+// Copyright 2023 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 trie
+
+import (
+	"math/big"
+	"testing"
+
+	"github.com/ethereum/go-ethereum/common"
+	"github.com/ethereum/go-ethereum/core/rawdb"
+	"github.com/ethereum/go-ethereum/core/types"
+	"github.com/ethereum/go-ethereum/trie/utils"
+	"github.com/gballet/go-verkle"
+)
+
+func TestVerkleIterator(t *testing.T) {
+	trie := NewVerkleTrie(verkle.New(), NewDatabase(rawdb.NewMemoryDatabase()), utils.NewPointCache())
+	account0 := &types.StateAccount{
+		Nonce:    1,
+		Balance:  big.NewInt(2),
+		Root:     emptyRoot,
+		CodeHash: nil,
+	}
+	// NOTE: the code size isn't written to the trie via TryUpdateAccount
+	// so it will be missing from the test nodes.
+	trie.TryUpdateAccount(zero[:], account0)
+	account1 := &types.StateAccount{
+		Nonce:    1337,
+		Balance:  big.NewInt(2000),
+		Root:     emptyRoot,
+		CodeHash: nil,
+	}
+	// This address is meant to hash to a value that has the same first byte as 0xbf
+	var clash = common.Hex2Bytes("69fd8034cdb20934dedffa7dccb4fb3b8062a8be")
+	trie.TryUpdateAccount(clash, account1)
+
+	// Manually go over every node to check that we get all
+	// the correct nodes.
+	it := trie.NodeIterator(nil)
+	var leafcount int
+	for it.Next(true) {
+		t.Logf("Node: %x", it.Path())
+		if it.Leaf() {
+			leafcount++
+			t.Logf("\tLeaf: %x", it.LeafKey())
+		}
+	}
+	if leafcount != 6 {
+		t.Fatalf("invalid leaf count: %d != 6", leafcount)
+	}
+}