core/rawdb: add chain iterator unit test

core/rawdb/chain_iterator_test.go

@@ -0,0 +1,67 @@
+// Copyright 2019 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 rawdb
+
+import (
+	"math/big"
+	"reflect"
+	"testing"
+
+	"github.com/ethereum/go-ethereum/common"
+	"github.com/ethereum/go-ethereum/core/types"
+	"github.com/ethereum/go-ethereum/ethdb"
+)
+
+func TestChainIterator(t *testing.T) {
+	// Construct test chain db
+	chainDb := NewMemoryDatabase()
+
+	var block *types.Block
+	for i := uint64(0); i <= 10; i++ {
+		if i == 0 {
+			block = types.NewBlock(&types.Header{Number: big.NewInt(int64(i))}, nil, nil, nil) // Empty genesis block
+		} else {
+			tx := types.NewTransaction(i, common.BytesToAddress([]byte{0x11}), big.NewInt(111), 1111, big.NewInt(11111), []byte{0x11, 0x11, 0x11})
+			block = types.NewBlock(&types.Header{Number: big.NewInt(int64(i))}, []*types.Transaction{tx}, nil, nil)
+		}
+		WriteBlock(chainDb, block)
+		WriteCanonicalHash(chainDb, block.Hash(), block.NumberU64())
+	}
+
+	var cases = []struct {
+		from, to uint64
+		reverse  bool
+		expect   []uint64
+	}{
+		{0, 11, true, []uint64{10, 9, 8, 7, 6, 5, 4, 3, 2, 1, 0}},
+		{0, 0, true, nil},
+		{10, 11, true, []uint64{10}},
+		{0, 11, false, []uint64{0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10}},
+		{0, 0, false, nil},
+		{10, 11, false, []uint64{10}},
+	}
+	for i, c := range cases {
+		var visit []uint64
+		err := iterateCanonicalChain(chainDb, c.from, c.to, "", nil, func(db ethdb.Batch, b *types.Block) { visit = append(visit, b.NumberU64()) }, c.reverse, false)
+		if err != nil {
+			t.Fatalf("Case %d failed, err %v", i, err)
+		}
+		if !reflect.DeepEqual(visit, c.expect) {
+			t.Fatalf("Case %d failed, visit element mismatch, want %v, got %v", i, c.expect, visit)
+		}
+	}
+}