core: implement Neo.Storage.Find interop

pkg/core/interop_neo.go

@@ -4,6 +4,7 @@ import (
 	"errors"
 	"fmt"
 	"math"
+	"strings"
 
 	"github.com/CityOfZion/neo-go/pkg/core/state"
 	"github.com/CityOfZion/neo-go/pkg/core/transaction"
@@ -429,7 +430,6 @@ func (ic *interopContext) accountIsStandard(v *vm.VM) error {
 	return nil
 }
 
-/*
 // storageFind finds stored key-value pair.
 func (ic *interopContext) storageFind(v *vm.VM) error {
 	stcInterface := v.Estack().Pop().Value()
@@ -446,16 +446,20 @@ func (ic *interopContext) storageFind(v *vm.VM) error {
 	if err != nil {
 		return err
 	}
+
+	filteredMap := make(map[interface{}]vm.StackItem)
 	for k, v := range siMap {
 		if strings.HasPrefix(k, prefix) {
-			_ = v
+			filteredMap[k] = vm.NewByteArrayItem(v.Value)
-			panic("TODO")
 		}
 	}
 
+	item := vm.NewMapIterator(filteredMap)
+	v.Estack().PushVal(item)
+
 	return nil
 }
-*/
+
 // createContractStateFromVM pops all contract state elements from the VM
 // evaluation stack, does a lot of checks and returns Contract if it
 // succeeds.

pkg/core/interop_neo_test.go

@@ -34,6 +34,72 @@ import (
  *  TestRuntimeDeserialize
  */
 
+func TestStorageFind(t *testing.T) {
+	v, contractState, context := createVMAndContractState(t)
+
+	skeys := [][]byte{{0x01, 0x02}, {0x02, 0x01}}
+	items := []*state.StorageItem{
+		{
+			Value: []byte{0x01, 0x02, 0x03, 0x04},
+		},
+		{
+			Value: []byte{0x04, 0x03, 0x02, 0x01},
+		},
+	}
+
+	require.NoError(t, context.dao.PutContractState(contractState))
+
+	scriptHash := contractState.ScriptHash()
+
+	for i := range skeys {
+		err := context.dao.PutStorageItem(scriptHash, skeys[i], items[i])
+		require.NoError(t, err)
+	}
+
+	t.Run("normal invocation", func(t *testing.T) {
+		v.Estack().PushVal([]byte{0x01})
+		v.Estack().PushVal(vm.NewInteropItem(&StorageContext{ScriptHash: scriptHash}))
+
+		err := context.storageFind(v)
+		require.NoError(t, err)
+
+		var iter *vm.InteropItem
+		require.NotPanics(t, func() { iter = v.Estack().Top().Interop() })
+
+		require.NoError(t, context.enumeratorNext(v))
+		require.True(t, v.Estack().Pop().Bool())
+
+		v.Estack().PushVal(iter)
+		require.NoError(t, context.iteratorKey(v))
+		require.Equal(t, []byte{0x01, 0x02}, v.Estack().Pop().Bytes())
+
+		v.Estack().PushVal(iter)
+		require.NoError(t, context.enumeratorValue(v))
+		require.Equal(t, []byte{0x01, 0x02, 0x03, 0x04}, v.Estack().Pop().Bytes())
+
+		v.Estack().PushVal(iter)
+		require.NoError(t, context.enumeratorNext(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))
+
+		require.Error(t, context.storageFind(v))
+	})
+
+	t.Run("invalid script hash", func(t *testing.T) {
+		invalidHash := scriptHash
+		invalidHash[0] = ^invalidHash[0]
+
+		v.Estack().PushVal([]byte{0x01})
+		v.Estack().PushVal(vm.NewInteropItem(&StorageContext{ScriptHash: invalidHash}))
+
+		require.Error(t, context.storageFind(v))
+	})
+}
+
 func TestHeaderGetVersion(t *testing.T) {
 	v, block, context := createVMAndPushBlock(t)
 

pkg/core/interops.go

@@ -173,6 +173,7 @@ var neoInterops = []interopedFunction{
 	{Name: "Neo.Runtime.Notify", Func: (*interopContext).runtimeNotify, Price: 1},
 	{Name: "Neo.Runtime.Serialize", Func: (*interopContext).runtimeSerialize, Price: 1},
 	{Name: "Neo.Storage.Delete", Func: (*interopContext).storageDelete, Price: 100},
+	{Name: "Neo.Storage.Find", Func: (*interopContext).storageFind, Price: 1},
 	{Name: "Neo.Storage.Get", Func: (*interopContext).storageGet, Price: 100},
 	{Name: "Neo.Storage.GetContext", Func: (*interopContext).storageGetContext, Price: 1},
 	{Name: "Neo.Storage.GetReadOnlyContext", Func: (*interopContext).storageGetReadOnlyContext, Price: 1},
@@ -187,7 +188,6 @@ var neoInterops = []interopedFunction{
 	{Name: "Neo.Transaction.GetUnspentCoins", Func: (*interopContext).txGetUnspentCoins, Price: 200},
 	{Name: "Neo.Transaction.GetWitnesses", Func: (*interopContext).txGetWitnesses, Price: 200},
 	{Name: "Neo.Witness.GetVerificationScript", Func: (*interopContext).witnessGetVerificationScript, Price: 100},
-	//		{Name: "Neo.Storage.Find",                Func: (*interopContext).storageFind, Price: 1},
 
 	// Aliases.
 	{Name: "Neo.Iterator.Next", Func: (*interopContext).enumeratorNext, Price: 1},

pkg/core/interops_test.go

@@ -64,6 +64,7 @@ func TestUnexpectedNonInterops(t *testing.T) {
 		(*interopContext).outputGetValue,
 		(*interopContext).storageContextAsReadOnly,
 		(*interopContext).storageDelete,
+		(*interopContext).storageFind,
 		(*interopContext).storageGet,
 		(*interopContext).storagePut,
 		(*interopContext).storagePutEx,