bsc/trie/iterator_test.go
Nick Johnson 555273495b trie: add difference iterator (#3637)
This PR implements a differenceIterator, which allows iterating over trie nodes
that exist in one trie but not in another. This is a prerequisite for most GC
strategies, in order to find obsolete nodes.
2017-02-22 23:49:34 +01:00

176 lines
4.3 KiB
Go

// Copyright 2014 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 (
"testing"
"github.com/ethereum/go-ethereum/common"
"github.com/ethereum/go-ethereum/ethdb"
)
func TestIterator(t *testing.T) {
trie := newEmpty()
vals := []struct{ k, v string }{
{"do", "verb"},
{"ether", "wookiedoo"},
{"horse", "stallion"},
{"shaman", "horse"},
{"doge", "coin"},
{"dog", "puppy"},
{"somethingveryoddindeedthis is", "myothernodedata"},
}
all := make(map[string]string)
for _, val := range vals {
all[val.k] = val.v
trie.Update([]byte(val.k), []byte(val.v))
}
trie.Commit()
found := make(map[string]string)
it := NewIterator(trie)
for it.Next() {
found[string(it.Key)] = string(it.Value)
}
for k, v := range all {
if found[k] != v {
t.Errorf("iterator value mismatch for %s: got %q want %q", k, found[k], v)
}
}
}
type kv struct {
k, v []byte
t bool
}
func TestIteratorLargeData(t *testing.T) {
trie := newEmpty()
vals := make(map[string]*kv)
for i := byte(0); i < 255; i++ {
value := &kv{common.LeftPadBytes([]byte{i}, 32), []byte{i}, false}
value2 := &kv{common.LeftPadBytes([]byte{10, i}, 32), []byte{i}, false}
trie.Update(value.k, value.v)
trie.Update(value2.k, value2.v)
vals[string(value.k)] = value
vals[string(value2.k)] = value2
}
it := NewIterator(trie)
for it.Next() {
vals[string(it.Key)].t = true
}
var untouched []*kv
for _, value := range vals {
if !value.t {
untouched = append(untouched, value)
}
}
if len(untouched) > 0 {
t.Errorf("Missed %d nodes", len(untouched))
for _, value := range untouched {
t.Error(value)
}
}
}
// Tests that the node iterator indeed walks over the entire database contents.
func TestNodeIteratorCoverage(t *testing.T) {
// Create some arbitrary test trie to iterate
db, trie, _ := makeTestTrie()
// Gather all the node hashes found by the iterator
hashes := make(map[common.Hash]struct{})
for it := NewNodeIterator(trie); it.Next(true); {
if it.Hash() != (common.Hash{}) {
hashes[it.Hash()] = struct{}{}
}
}
// Cross check the hashes and the database itself
for hash := range hashes {
if _, err := db.Get(hash.Bytes()); err != nil {
t.Errorf("failed to retrieve reported node %x: %v", hash, err)
}
}
for _, key := range db.(*ethdb.MemDatabase).Keys() {
if _, ok := hashes[common.BytesToHash(key)]; !ok {
t.Errorf("state entry not reported %x", key)
}
}
}
func TestDifferenceIterator(t *testing.T) {
triea := newEmpty()
valsa := []struct{ k, v string }{
{"bar", "b"},
{"barb", "ba"},
{"bars", "bb"},
{"bard", "bc"},
{"fab", "z"},
{"foo", "a"},
{"food", "ab"},
{"foos", "aa"},
}
for _, val := range valsa {
triea.Update([]byte(val.k), []byte(val.v))
}
triea.Commit()
trieb := newEmpty()
valsb := []struct{ k, v string }{
{"aardvark", "c"},
{"bar", "b"},
{"barb", "bd"},
{"bars", "be"},
{"fab", "z"},
{"foo", "a"},
{"foos", "aa"},
{"food", "ab"},
{"jars", "d"},
}
for _, val := range valsb {
trieb.Update([]byte(val.k), []byte(val.v))
}
trieb.Commit()
found := make(map[string]string)
di, _ := NewDifferenceIterator(NewNodeIterator(triea), NewNodeIterator(trieb))
it := NewIteratorFromNodeIterator(di)
for it.Next() {
found[string(it.Key)] = string(it.Value)
}
all := []struct{ k, v string }{
{"aardvark", "c"},
{"barb", "bd"},
{"bars", "be"},
{"jars", "d"},
}
for _, item := range all {
if found[item.k] != item.v {
t.Errorf("iterator value mismatch for %s: got %q want %q", item.k, found[item.k], item.v)
}
}
if len(found) != len(all) {
t.Errorf("iterator count mismatch: got %d values, want %d", len(found), len(all))
}
}