core: sort results of Storage.Find and NEO.getRegisterValidators

Closes #909
We need to match elements order with C# implementation.

pkg/core/interop_neo.go

@@ -1,10 +1,11 @@
 package core
 
 import (
+	"bytes"
 	"errors"
 	"fmt"
 	"math"
-	"strings"
+	"sort"
 
 	"github.com/nspcc-dev/neo-go/pkg/core/interop"
 	"github.com/nspcc-dev/neo-go/pkg/core/interop/runtime"
@@ -422,19 +423,20 @@ func storageFind(ic *interop.Context, v *vm.VM) error {
 	if err != nil {
 		return err
 	}
-	prefix := string(v.Estack().Pop().Bytes())
+	prefix := v.Estack().Pop().Bytes()
-	siMap, err := ic.DAO.GetStorageItems(stc.ScriptHash)
+	siMap, err := ic.DAO.GetStorageItemsWithPrefix(stc.ScriptHash, prefix)
 	if err != nil {
 		return err
 	}
 
 	filteredMap := vm.NewMapItem()
 	for k, v := range siMap {
-		if strings.HasPrefix(k, prefix) {
+		filteredMap.Add(vm.NewByteArrayItem(append(prefix, []byte(k)...)), vm.NewByteArrayItem(v.Value))
-			filteredMap.Add(vm.NewByteArrayItem([]byte(k)),
-				vm.NewByteArrayItem(v.Value))
-		}
 	}
+	sort.Slice(filteredMap.Value().([]vm.MapElement), func(i, j int) bool {
+		return bytes.Compare(filteredMap.Value().([]vm.MapElement)[i].Key.Value().([]byte),
+			filteredMap.Value().([]vm.MapElement)[j].Key.Value().([]byte)) == -1
+	})
 
 	item := vm.NewMapIterator(filteredMap)
 	v.Estack().PushVal(item)

pkg/core/interop_neo_test.go

@@ -51,7 +51,7 @@ func TestStorageFind(t *testing.T) {
 	v, contractState, context, chain := createVMAndContractState(t)
 	defer chain.Close()
 
-	skeys := [][]byte{{0x01, 0x02}, {0x02, 0x01}}
+	skeys := [][]byte{{0x01, 0x02}, {0x02, 0x01}, {0x01, 0x01}}
 	items := []*state.StorageItem{
 		{
 			Value: []byte{0x01, 0x02, 0x03, 0x04},
@@ -59,6 +59,9 @@ func TestStorageFind(t *testing.T) {
 		{
 			Value: []byte{0x04, 0x03, 0x02, 0x01},
 		},
+		{
+			Value: []byte{0x03, 0x04, 0x05, 0x06},
+		},
 	}
 
 	require.NoError(t, context.DAO.PutContractState(contractState))
@@ -83,6 +86,18 @@ func TestStorageFind(t *testing.T) {
 		require.NoError(t, enumerator.Next(context, v))
 		require.True(t, v.Estack().Pop().Bool())
 
+		v.Estack().PushVal(iter)
+		require.NoError(t, iterator.Key(context, v))
+		require.Equal(t, []byte{0x01, 0x01}, v.Estack().Pop().Bytes())
+
+		v.Estack().PushVal(iter)
+		require.NoError(t, enumerator.Value(context, v))
+		require.Equal(t, []byte{0x03, 0x04, 0x05, 0x06}, v.Estack().Pop().Bytes())
+
+		v.Estack().PushVal(iter)
+		require.NoError(t, enumerator.Next(context, v))
+		require.True(t, v.Estack().Pop().Bool())
+
 		v.Estack().PushVal(iter)
 		require.NoError(t, iterator.Key(context, v))
 		require.Equal(t, []byte{0x01, 0x02}, v.Estack().Pop().Bytes())
@@ -96,6 +111,17 @@ func TestStorageFind(t *testing.T) {
 		require.False(t, v.Estack().Pop().Bool())
 	})
 
+	t.Run("normal invocation, empty result", func(t *testing.T) {
+		v.Estack().PushVal([]byte{0x03})
+		v.Estack().PushVal(vm.NewInteropItem(&StorageContext{ScriptHash: scriptHash}))
+
+		err := storageFind(context, v)
+		require.NoError(t, err)
+
+		require.NoError(t, enumerator.Next(context, v))
+		require.False(t, v.Estack().Pop().Bool())
+	})
+
 	t.Run("invalid type for StorageContext", func(t *testing.T) {
 		v.Estack().PushVal([]byte{0x01})
 		v.Estack().PushVal(vm.NewInteropItem(nil))

pkg/core/native/native_neo.go

@@ -3,6 +3,7 @@ package native
 import (
 	"math/big"
 	"sort"
+	"strings"
 
 	"github.com/nspcc-dev/neo-go/pkg/core/blockchainer"
 	"github.com/nspcc-dev/neo-go/pkg/core/dao"
@@ -344,6 +345,7 @@ func (n *NEO) getRegisteredValidators(d dao.DAO) ([]keyWithVotes, error) {
 		}
 		arr = append(arr, keyWithVotes{key, &votes.Balance})
 	}
+	sort.Slice(arr, func(i, j int) bool { return strings.Compare(arr[i].Key, arr[j].Key) == -1 })
 	return arr, nil
 }