Merge pull request #963 from nspcc-dev/fix/tests

vm: restore JSON tests for NEO3
2024-12-24 09:25:21 +00:00 · 2020-05-22 14:34:08 +03:00 · 2020-05-22 14:34:08 +03:00 · 5ea51312e6
commit 5ea51312e6
parent 9b2d045a29 d26758dd31
14 changed files with 436 additions and 335 deletions
--- a/pkg/compiler/binary_expr_test.go
+++ b/pkg/compiler/binary_expr_test.go
@ -26,7 +26,7 @@ var binaryExprTestCases = []testCase{
 			return x
 		}
 		`,
-		[]byte{},
+		big.NewInt(0),
 	},
 	{
 		"simple div",
@ -97,7 +97,7 @@ var binaryExprTestCases = []testCase{
 			return 0
 		}
 		`,
-		[]byte{},
+		big.NewInt(0),
 	},
 	{
 		"compare equal strings with eql",
@ -139,7 +139,7 @@ var binaryExprTestCases = []testCase{
 			return 0
 		}
 		`,
-		[]byte{},
+		big.NewInt(0),
 	},
 	{
 		"compare equal ints with eql",
@ -167,7 +167,7 @@ var binaryExprTestCases = []testCase{
 			return 0
 		}
 		`,
-		[]byte{},
+		big.NewInt(0),
 	},
 	{
 		"compare not equal ints with eql",
@ -181,7 +181,7 @@ var binaryExprTestCases = []testCase{
 			return 0
 		}
 		`,
-		[]byte{},
+		big.NewInt(0),
 	},
 	{
 		"compare not equal ints with neq",
--- a/pkg/compiler/for_test.go
+++ b/pkg/compiler/for_test.go
@ -276,7 +276,7 @@ func TestIfUnaryInvert(t *testing.T) {
 			return 0
 		}
 	`
-	eval(t, src, []byte{})
+	eval(t, src, big.NewInt(0))
 }

 func TestAppendByte(t *testing.T) {
--- a/pkg/compiler/function_call_test.go
+++ b/pkg/compiler/function_call_test.go
@ -39,7 +39,7 @@ func TestNotAssignedFunctionCall(t *testing.T) {
 	// disable stack checks because it is hard right now
 	// to distinguish between simple function call traversal
 	// and the same traversal inside an assignment.
-	evalWithoutStackChecks(t, src, []byte{})
+	evalWithoutStackChecks(t, src, big.NewInt(0))
 }

 func TestMultipleFunctionCalls(t *testing.T) {
--- a/pkg/compiler/if_test.go
+++ b/pkg/compiler/if_test.go
@ -30,7 +30,7 @@ func TestGT(t *testing.T) {
 			return 0
 		}
 	`
-	eval(t, src, []byte{})
+	eval(t, src, big.NewInt(0))
 }

 func TestGTE(t *testing.T) {
@ -44,7 +44,7 @@ func TestGTE(t *testing.T) {
 			return 0
 		}
 	`
-	eval(t, src, []byte{})
+	eval(t, src, big.NewInt(0))
 }

 func TestLAND(t *testing.T) {
@ -89,5 +89,5 @@ func TestNestedIF(t *testing.T) {
 			return 0
 		}
 	`
-	eval(t, src, []byte{})
+	eval(t, src, big.NewInt(0))
 }
--- a/pkg/compiler/import_test.go
+++ b/pkg/compiler/import_test.go
@ -32,7 +32,7 @@ func TestImportStruct(t *testing.T) {
 			 return b.Y
 	 	}
 	 `
-	eval(t, src, []byte{})
+	eval(t, src, big.NewInt(0))
 }

 func TestMultipleDirFileImport(t *testing.T) {
--- a/pkg/compiler/struct_test.go
+++ b/pkg/compiler/struct_test.go
@ -255,7 +255,7 @@ var structTestCases = []testCase{
 			return t.y
 		}
 		`,
-		[]byte{},
+		big.NewInt(0),
 	},
 	{
 		"test return struct from func",
--- a/pkg/vm/json_test.go
+++ b/pkg/vm/json_test.go
@ -11,6 +11,8 @@ import (
 	"math/big"
 	"os"
 	"path/filepath"
+	"regexp"
+	"strconv"
 	"strings"
 	"testing"

@ -37,12 +39,12 @@ type (
 	vmUTExecutionContextState struct {
 		Instruction        string          `json:"nextInstruction"`
 		InstructionPointer int             `json:"instructionPointer"`
-		AStack             []vmUTStackItem `json:"altStack"`
 		EStack             []vmUTStackItem `json:"evaluationStack"`
+		StaticFields       []vmUTStackItem `json:"staticFields"`
 	}

 	vmUTExecutionEngineState struct {
-		State           vmUTState                   `json:"state"`
+		State           State                       `json:"state"`
 		ResultStack     []vmUTStackItem             `json:"resultStack"`
 		InvocationStack []vmUTExecutionContextState `json:"invocationStack"`
 	}
@ -59,8 +61,6 @@ type (
 		Result  vmUTExecutionEngineState `json:"result"`
 	}

-	vmUTState State
-
 	vmUTStackItemType string
 )

@ -73,25 +73,27 @@ type stackItemAUX struct {
 }

 const (
-	vmExecute  vmUTActionType = "Execute"
-	vmStepInto vmUTActionType = "StepInto"
-	vmStepOut  vmUTActionType = "StepOut"
-	vmStepOver vmUTActionType = "StepOver"
+	vmExecute  vmUTActionType = "execute"
+	vmStepInto vmUTActionType = "stepinto"
+	vmStepOut  vmUTActionType = "stepout"
+	vmStepOver vmUTActionType = "stepover"

-	typeArray     vmUTStackItemType = "Array"
-	typeBoolean   vmUTStackItemType = "Boolean"
-	typeByteArray vmUTStackItemType = "ByteArray"
-	typeInteger   vmUTStackItemType = "Integer"
-	typeInterop   vmUTStackItemType = "Interop"
-	typeMap       vmUTStackItemType = "Map"
-	typeString    vmUTStackItemType = "String"
-	typeStruct    vmUTStackItemType = "Struct"
+	typeArray      vmUTStackItemType = "array"
+	typeBoolean    vmUTStackItemType = "boolean"
+	typeBuffer     vmUTStackItemType = "buffer"
+	typeByteString vmUTStackItemType = "bytestring"
+	typeInteger    vmUTStackItemType = "integer"
+	typeInterop    vmUTStackItemType = "interop"
+	typeMap        vmUTStackItemType = "map"
+	typeNull       vmUTStackItemType = "null"
+	typePointer    vmUTStackItemType = "pointer"
+	typeString     vmUTStackItemType = "string"
+	typeStruct     vmUTStackItemType = "struct"

 	testsDir = "testdata/neo-vm/tests/neo-vm.Tests/Tests/"
 )

 func TestUT(t *testing.T) {
-	t.Skip()
 	testsRan := false
 	err := filepath.Walk(testsDir, func(path string, info os.FileInfo, err error) error {
 		if !strings.HasSuffix(path, ".json") {
@ -110,7 +112,7 @@ func TestUT(t *testing.T) {
 func getTestingInterop(id uint32) *InteropFuncPrice {
 	if id == binary.LittleEndian.Uint32([]byte{0x77, 0x77, 0x77, 0x77}) {
 		return &InteropFuncPrice{InteropFunc(func(v *VM) error {
-			v.estack.Push(&Element{value: (*InteropItem)(nil)})
+			v.estack.PushVal(&InteropItem{new(int)})
 			return nil
 		}), 0}
 	}
@ -121,12 +123,24 @@ func testFile(t *testing.T, filename string) {
 	data, err := ioutil.ReadFile(filename)
 	require.NoError(t, err)

+	// get rid of possible BOM
+	if len(data) > 2 && data[0] == 0xef && data[1] == 0xbb && data[2] == 0xbf {
+		data = data[3:]
+	}
+	if strings.HasSuffix(filename, "MEMCPY.json") {
+		return // FIXME not a valid JSON https://github.com/neo-project/neo-vm/issues/322
+	}
+
 	ut := new(vmUT)
-	require.NoError(t, json.Unmarshal(data, ut))
+	require.NoErrorf(t, json.Unmarshal(data, ut), "file: %s", filename)

 	t.Run(ut.Category+":"+ut.Name, func(t *testing.T) {
+		isRot := strings.HasSuffix(filename, "ROT.json")
 		for i := range ut.Tests {
 			test := ut.Tests[i]
+			if isRot && test.Name == "Without push" {
+				return // FIXME #927 single ROT is interpreted as PUSH1
+			}
 			t.Run(ut.Tests[i].Name, func(t *testing.T) {
 				prog := []byte(test.Script)
 				vm := load(prog)
@ -136,8 +150,8 @@ func testFile(t *testing.T, filename string) {
 				for i := range test.Steps {
 					execStep(t, vm, test.Steps[i])
 					result := test.Steps[i].Result
-					require.Equal(t, State(result.State), vm.state)
-					if result.State == vmUTState(faultState) { // do not compare stacks on fault
+					require.Equal(t, result.State, vm.state)
+					if result.State == faultState { // do not compare stacks on fault
 						continue
 					}

@ -146,10 +160,12 @@ func testFile(t *testing.T, filename string) {
 							ctx := vm.istack.Peek(i).Value().(*Context)
 							if ctx.nextip < len(ctx.prog) {
 								require.Equal(t, s.InstructionPointer, ctx.nextip)
-								require.Equal(t, s.Instruction, opcode.Opcode(ctx.prog[ctx.nextip]).String())
+								op, err := opcode.FromString(s.Instruction)
+								require.NoError(t, err)
+								require.Equal(t, op, opcode.Opcode(ctx.prog[ctx.nextip]))
 							}
 							compareStacks(t, s.EStack, vm.estack)
-							compareStacks(t, s.AStack, vm.astack)
+							compareSlots(t, s.StaticFields, vm.static)
 						}
 					}

@ -180,31 +196,47 @@ func compareItems(t *testing.T, a, b StackItem) {
 		default:
 			require.Fail(t, "wrong type")
 		}
+	case *PointerItem:
+		p, ok := b.(*PointerItem)
+		require.True(t, ok)
+		require.Equal(t, si.pos, p.pos) // there no script in test files
 	default:
 		require.Equal(t, a, b)
 	}
 }

 func compareStacks(t *testing.T, expected []vmUTStackItem, actual *Stack) {
+	compareItemArrays(t, expected, actual.Len(), func(i int) StackItem { return actual.Peek(i).Item() })
+}
+
+func compareSlots(t *testing.T, expected []vmUTStackItem, actual *Slot) {
+	if actual == nil && len(expected) == 0 {
+		return
+	}
+	require.NotNil(t, actual)
+	compareItemArrays(t, expected, actual.Size(), actual.Get)
+}
+
+func compareItemArrays(t *testing.T, expected []vmUTStackItem, n int, getItem func(i int) StackItem) {
 	if expected == nil {
 		return
 	}

-	require.Equal(t, len(expected), actual.Len())
+	require.Equal(t, len(expected), n)
 	for i, item := range expected {
-		e := actual.Peek(i)
-		require.NotNil(t, e)
+		it := getItem(i)
+		require.NotNil(t, it)

 		if item.Type == typeInterop {
-			require.IsType(t, (*InteropItem)(nil), e.value)
+			require.IsType(t, (*InteropItem)(nil), it)
 			continue
 		}
-		compareItems(t, item.toStackItem(), e.value)
+		compareItems(t, item.toStackItem(), it)
 	}
 }

 func (v *vmUTStackItem) toStackItem() StackItem {
-	switch v.Type {
+	switch v.Type.toLower() {
 	case typeArray:
 		items := v.Value.([]vmUTStackItem)
 		result := make([]StackItem, len(items))
@ -217,20 +249,19 @@ func (v *vmUTStackItem) toStackItem() StackItem {
 	case typeString:
 		panic("not implemented")
 	case typeMap:
-		items := v.Value.(map[string]vmUTStackItem)
-		result := NewMapItem()
-		for k, v := range items {
-			var item vmUTStackItem
-			_ = json.Unmarshal([]byte(`"`+k+`"`), &item)
-			result.Add(item.toStackItem(), v.toStackItem())
-		}
-		return result
+		return v.Value.(*MapItem)
 	case typeInterop:
 		panic("not implemented")
-	case typeByteArray:
+	case typeByteString:
 		return &ByteArrayItem{
 			v.Value.([]byte),
 		}
+	case typeBuffer:
+		return &BufferItem{v.Value.([]byte)}
+	case typePointer:
+		return NewPointerItem(v.Value.(int), nil)
+	case typeNull:
+		return NullItem{}
 	case typeBoolean:
 		return &BoolItem{
 			v.Value.(bool),
@ -249,14 +280,14 @@ func (v *vmUTStackItem) toStackItem() StackItem {
 			value: result,
 		}
 	default:
-		panic("invalid type")
+		panic(fmt.Sprintf("invalid type: %s", v.Type))
 	}
 }

 func execStep(t *testing.T, v *VM, step vmUTStep) {
 	for i, a := range step.Actions {
 		var err error
-		switch a {
+		switch a.toLower() {
 		case vmExecute:
 			err = v.Run()
 		case vmStepInto:
@ -276,30 +307,65 @@ func execStep(t *testing.T, v *VM, step vmUTStep) {
 	}
 }

-func (v *vmUTState) UnmarshalJSON(data []byte) error {
-	switch s := string(data); s {
-	case `"Break"`:
-		*v = vmUTState(breakState)
-	case `"Fault"`:
-		*v = vmUTState(faultState)
-	case `"Halt"`:
-		*v = vmUTState(haltState)
-	default:
-		panic(fmt.Sprintf("invalid state: %s", s))
+func jsonStringToInteger(s string) StackItem {
+	b, err := decodeHex(s)
+	if err == nil {
+		return NewBigIntegerItem(new(big.Int).SetBytes(b))
 	}
 	return nil
 }

+func (v vmUTStackItemType) toLower() vmUTStackItemType {
+	return vmUTStackItemType(strings.ToLower(string(v)))
+}
+
 func (v *vmUTScript) UnmarshalJSON(data []byte) error {
-	b, err := decodeBytes(data)
-	if err != nil {
+	var ops []string
+	if err := json.Unmarshal(data, &ops); err != nil {
 		return err
 	}

-	*v = vmUTScript(b)
+	var script []byte
+	for i := range ops {
+		if b, ok := decodeSingle(ops[i]); ok {
+			script = append(script, b...)
+		} else {
+			const regex = `(?P<hex>(?:0x)?[0-9a-zA-Z]+)\*(?P<num>[0-9]+)`
+			re := regexp.MustCompile(regex)
+			ss := re.FindStringSubmatch(ops[i])
+			if len(ss) != 3 {
+				return fmt.Errorf("invalid script part: %s", ops[i])
+			}
+			b, ok := decodeSingle(ss[1])
+			if !ok {
+				return fmt.Errorf("invalid script part: %s", ops[i])
+			}
+			num, err := strconv.Atoi(ss[2])
+			if err != nil {
+				return fmt.Errorf("invalid script part: %s", ops[i])
+			}
+			for i := 0; i < num; i++ {
+				script = append(script, b...)
+			}
+		}
+	}
+
+	*v = script
 	return nil
 }

+func decodeSingle(s string) ([]byte, bool) {
+	if op, err := opcode.FromString(s); err == nil {
+		return []byte{byte(op)}, true
+	}
+	b, err := decodeHex(s)
+	return b, err == nil
+}
+
+func (v vmUTActionType) toLower() vmUTActionType {
+	return vmUTActionType(strings.ToLower(string(v)))
+}
+
 func (v *vmUTActionType) UnmarshalJSON(data []byte) error {
 	return json.Unmarshal(data, (*string)(v))
 }
@ -312,14 +378,14 @@ func (v *vmUTStackItem) UnmarshalJSON(data []byte) error {

 	v.Type = si.Type

-	switch si.Type {
+	switch typ := si.Type.toLower(); typ {
 	case typeArray, typeStruct:
 		var a []vmUTStackItem
 		if err := json.Unmarshal(si.Value, &a); err != nil {
 			return err
 		}
 		v.Value = a
-	case typeInteger:
+	case typeInteger, typePointer:
 		num := new(big.Int)
 		var a int64
 		var s string
@ -330,27 +396,57 @@ func (v *vmUTStackItem) UnmarshalJSON(data []byte) error {
 		} else {
 			panic(fmt.Sprintf("invalid integer: %v", si.Value))
 		}
-		v.Value = num
+		if typ == typePointer {
+			v.Value = int(num.Int64())
+		} else {
+			v.Value = num
+		}
 	case typeBoolean:
 		var b bool
 		if err := json.Unmarshal(si.Value, &b); err != nil {
 			return err
 		}
 		v.Value = b
-	case typeByteArray:
+	case typeByteString, typeBuffer:
 		b, err := decodeBytes(si.Value)
 		if err != nil {
 			return err
 		}
 		v.Value = b
-	case typeInterop:
+	case typeInterop, typeNull:
 		v.Value = nil
 	case typeMap:
-		var m map[string]vmUTStackItem
-		if err := json.Unmarshal(si.Value, &m); err != nil {
-			return err
+		// we want to have the same order as in test file, so a custom decoder is used
+		d := json.NewDecoder(bytes.NewReader(si.Value))
+		if tok, err := d.Token(); err != nil || tok != json.Delim('{') {
+			return fmt.Errorf("invalid map start")
 		}
-		v.Value = m
+
+		result := NewMapItem()
+		for {
+			tok, err := d.Token()
+			if err != nil {
+				return err
+			} else if tok == json.Delim('}') {
+				break
+			}
+			key, ok := tok.(string)
+			if !ok {
+				return fmt.Errorf("string expected in map key")
+			}
+
+			var it vmUTStackItem
+			if err := d.Decode(&it); err != nil {
+				return fmt.Errorf("can't decode map value: %v", err)
+			}
+
+			item := jsonStringToInteger(key)
+			if item == nil {
+				return fmt.Errorf("can't unmarshal StackItem %s", key)
+			}
+			result.Add(item, it.toStackItem())
+		}
+		v.Value = result
 	case typeString:
 		panic("not implemented")
 	default:
@ -366,12 +462,18 @@ func decodeBytes(data []byte) ([]byte, error) {
 		return []byte{}, nil
 	}

-	hdata := data[3 : len(data)-1]
-	if b, err := hex.DecodeString(string(hdata)); err == nil {
+	data = data[1 : len(data)-1] // strip quotes
+	if b, err := decodeHex(string(data)); err == nil {
 		return b, nil
 	}

-	data = data[1 : len(data)-1]
 	r := base64.NewDecoder(base64.StdEncoding, bytes.NewReader(data))
 	return ioutil.ReadAll(r)
 }
+
+func decodeHex(s string) ([]byte, error) {
+	if strings.HasPrefix(s, "0x") {
+		s = s[2:]
+	}
+	return hex.DecodeString(s)
+}
--- a/pkg/vm/opcode/from_string.go
+++ b/pkg/vm/opcode/from_string.go
@ -0,0 +1,20 @@
+package opcode
+
+import "errors"
+
+var stringToOpcode = make(map[string]Opcode)
+
+func init() {
+	for i := 0; i < 255; i++ {
+		op := Opcode(i)
+		stringToOpcode[op.String()] = op
+	}
+}
+
+// FromString converts string representation to and opcode itself.
+func FromString(s string) (Opcode, error) {
+	if op, ok := stringToOpcode[s]; ok {
+		return op, nil
+	}
+	return 0, errors.New("invalid opcode")
+}
--- a/pkg/vm/opcode/opcode.go
+++ b/pkg/vm/opcode/opcode.go
@ -46,25 +46,25 @@ const (
 	// Flow control
 	NOP       Opcode = 0x21
 	JMP       Opcode = 0x22
-	JMPL      Opcode = 0x23
+	JMPL      Opcode = 0x23 // JMP_L
 	JMPIF     Opcode = 0x24
-	JMPIFL    Opcode = 0x25
+	JMPIFL    Opcode = 0x25 // JMPIF_L
 	JMPIFNOT  Opcode = 0x26
-	JMPIFNOTL Opcode = 0x27
+	JMPIFNOTL Opcode = 0x27 // JMPIFNOT_L
 	JMPEQ     Opcode = 0x28
-	JMPEQL    Opcode = 0x29
+	JMPEQL    Opcode = 0x29 // JMPEQ_L
 	JMPNE     Opcode = 0x2A
-	JMPNEL    Opcode = 0x2B
+	JMPNEL    Opcode = 0x2B // JMPNE_L
 	JMPGT     Opcode = 0x2C
-	JMPGTL    Opcode = 0x2D
+	JMPGTL    Opcode = 0x2D // JMPGT_L
 	JMPGE     Opcode = 0x2E
-	JMPGEL    Opcode = 0x2F
+	JMPGEL    Opcode = 0x2F // JMPGE_L
 	JMPLT     Opcode = 0x30
-	JMPLTL    Opcode = 0x31
+	JMPLTL    Opcode = 0x31 // JMPLT_L
 	JMPLE     Opcode = 0x32
-	JMPLEL    Opcode = 0x33
+	JMPLEL    Opcode = 0x33 // JMPLE_L
 	CALL      Opcode = 0x34
-	CALLL     Opcode = 0x35
+	CALLL     Opcode = 0x35 // CALL_L
 	CALLA     Opcode = 0x36

 	// Exceptions
@ -86,8 +86,8 @@ const (
 	PICK     Opcode = 0x4D
 	TUCK     Opcode = 0x4E
 	SWAP     Opcode = 0x50
-	OLDPUSH1 Opcode = 0x51 // FIXME remove #927
 	ROT      Opcode = 0x51
+	OLDPUSH1 Opcode = 0x51 // FIXME remove #927
 	ROLL     Opcode = 0x52
 	REVERSE3 Opcode = 0x53
 	REVERSE4 Opcode = 0x54
@ -193,7 +193,7 @@ const (
 	UNPACK       Opcode = 0xC1
 	NEWARRAY0    Opcode = 0xC2
 	NEWARRAY     Opcode = 0xC3
-	NEWARRAYT    Opcode = 0xC4
+	NEWARRAYT    Opcode = 0xC4 // NEWARRAY_T
 	NEWSTRUCT0   Opcode = 0xC5
 	NEWSTRUCT    Opcode = 0xC6
 	NEWMAP       Opcode = 0xC8
--- a/pkg/vm/opcode/opcode_string.go
+++ b/pkg/vm/opcode/opcode_string.go
@ -1,4 +1,4 @@
-// Code generated by "stringer -type Opcode"; DO NOT EDIT.
+// Code generated by "stringer -type Opcode -linecomment"; DO NOT EDIT.

 package opcode

@ -76,8 +76,8 @@ func _() {
 	_ = x[PICK-77]
 	_ = x[TUCK-78]
 	_ = x[SWAP-80]
-	_ = x[OLDPUSH1-81]
 	_ = x[ROT-81]
+	_ = x[OLDPUSH1-81]
 	_ = x[ROLL-82]
 	_ = x[REVERSE3-83]
 	_ = x[REVERSE4-84]
@ -192,7 +192,7 @@ func _() {
 	_ = x[CONVERT-219]
 }

-const _Opcode_name = "PUSHINT8PUSHINT16PUSHINT32PUSHINT64PUSHINT128PUSHINT256PUSHAPUSHNULLPUSHDATA1PUSHDATA2PUSHDATA4PUSHM1PUSH0PUSH1PUSH2PUSH3PUSH4PUSH5PUSH6PUSH7PUSH8PUSH9PUSH10PUSH11PUSH12PUSH13PUSH14PUSH15PUSH16NOPJMPJMPLJMPIFJMPIFLJMPIFNOTJMPIFNOTLJMPEQJMPEQLJMPNEJMPNELJMPGTJMPGTLJMPGEJMPGELJMPLTJMPLTLJMPLEJMPLELCALLCALLLCALLAABORTASSERTTHROWRETSYSCALLDEPTHDROPNIPXDROPCLEARDUPOVERPICKTUCKSWAPOLDPUSH1ROLLREVERSE3REVERSE4REVERSENINITSSLOTINITSLOTLDSFLD0LDSFLD1LDSFLD2LDSFLD3LDSFLD4LDSFLD5LDSFLD6LDSFLDSTSFLD0STSFLD1STSFLD2STSFLD3STSFLD4STSFLD5STSFLD6STSFLDLDLOC0LDLOC1LDLOC2LDLOC3LDLOC4LDLOC5LDLOC6LDLOCSTLOC0STLOC1STLOC2STLOC3STLOC4STLOC5STLOC6STLOCLDARG0LDARG1LDARG2LDARG3LDARG4LDARG5LDARG6LDARGSTARG0STARG1STARG2STARG3STARG4STARG5STARG6STARGNEWBUFFERMEMCPYCATSUBSTRLEFTRIGHTINVERTANDORXOREQUALNOTEQUALSIGNABSNEGATEINCDECADDSUBMULDIVMODSHLSHRNOTBOOLANDBOOLORNZNUMEQUALNUMNOTEQUALLTLTEGTGTEMINMAXWITHINPACKUNPACKNEWARRAY0NEWARRAYNEWARRAYTNEWSTRUCT0NEWSTRUCTNEWMAPSIZEHASKEYKEYSVALUESPICKITEMAPPENDSETITEMREVERSEITEMSREMOVECLEARITEMSISNULLISTYPECONVERT"
+const _Opcode_name = "PUSHINT8PUSHINT16PUSHINT32PUSHINT64PUSHINT128PUSHINT256PUSHAPUSHNULLPUSHDATA1PUSHDATA2PUSHDATA4PUSHM1PUSH0PUSH1PUSH2PUSH3PUSH4PUSH5PUSH6PUSH7PUSH8PUSH9PUSH10PUSH11PUSH12PUSH13PUSH14PUSH15PUSH16NOPJMPJMP_LJMPIFJMPIF_LJMPIFNOTJMPIFNOT_LJMPEQJMPEQ_LJMPNEJMPNE_LJMPGTJMPGT_LJMPGEJMPGE_LJMPLTJMPLT_LJMPLEJMPLE_LCALLCALL_LCALLAABORTASSERTTHROWRETSYSCALLDEPTHDROPNIPXDROPCLEARDUPOVERPICKTUCKSWAPROTROLLREVERSE3REVERSE4REVERSENINITSSLOTINITSLOTLDSFLD0LDSFLD1LDSFLD2LDSFLD3LDSFLD4LDSFLD5LDSFLD6LDSFLDSTSFLD0STSFLD1STSFLD2STSFLD3STSFLD4STSFLD5STSFLD6STSFLDLDLOC0LDLOC1LDLOC2LDLOC3LDLOC4LDLOC5LDLOC6LDLOCSTLOC0STLOC1STLOC2STLOC3STLOC4STLOC5STLOC6STLOCLDARG0LDARG1LDARG2LDARG3LDARG4LDARG5LDARG6LDARGSTARG0STARG1STARG2STARG3STARG4STARG5STARG6STARGNEWBUFFERMEMCPYCATSUBSTRLEFTRIGHTINVERTANDORXOREQUALNOTEQUALSIGNABSNEGATEINCDECADDSUBMULDIVMODSHLSHRNOTBOOLANDBOOLORNZNUMEQUALNUMNOTEQUALLTLTEGTGTEMINMAXWITHINPACKUNPACKNEWARRAY0NEWARRAYNEWARRAY_TNEWSTRUCT0NEWSTRUCTNEWMAPSIZEHASKEYKEYSVALUESPICKITEMAPPENDSETITEMREVERSEITEMSREMOVECLEARITEMSISNULLISTYPECONVERT"

 var _Opcode_map = map[Opcode]string{
 	0:   _Opcode_name[0:8],
@ -226,154 +226,154 @@ var _Opcode_map = map[Opcode]string{
 	32:  _Opcode_name[187:193],
 	33:  _Opcode_name[193:196],
 	34:  _Opcode_name[196:199],
-	35:  _Opcode_name[199:203],
-	36:  _Opcode_name[203:208],
-	37:  _Opcode_name[208:214],
-	38:  _Opcode_name[214:222],
-	39:  _Opcode_name[222:231],
-	40:  _Opcode_name[231:236],
-	41:  _Opcode_name[236:242],
-	42:  _Opcode_name[242:247],
-	43:  _Opcode_name[247:253],
-	44:  _Opcode_name[253:258],
-	45:  _Opcode_name[258:264],
-	46:  _Opcode_name[264:269],
-	47:  _Opcode_name[269:275],
-	48:  _Opcode_name[275:280],
-	49:  _Opcode_name[280:286],
-	50:  _Opcode_name[286:291],
-	51:  _Opcode_name[291:297],
-	52:  _Opcode_name[297:301],
-	53:  _Opcode_name[301:306],
-	54:  _Opcode_name[306:311],
-	55:  _Opcode_name[311:316],
-	56:  _Opcode_name[316:322],
-	58:  _Opcode_name[322:327],
-	64:  _Opcode_name[327:330],
-	65:  _Opcode_name[330:337],
-	67:  _Opcode_name[337:342],
-	69:  _Opcode_name[342:346],
-	70:  _Opcode_name[346:349],
-	72:  _Opcode_name[349:354],
-	73:  _Opcode_name[354:359],
-	74:  _Opcode_name[359:362],
-	75:  _Opcode_name[362:366],
-	77:  _Opcode_name[366:370],
-	78:  _Opcode_name[370:374],
-	80:  _Opcode_name[374:378],
-	81:  _Opcode_name[378:386],
-	82:  _Opcode_name[386:390],
-	83:  _Opcode_name[390:398],
-	84:  _Opcode_name[398:406],
-	85:  _Opcode_name[406:414],
-	86:  _Opcode_name[414:423],
-	87:  _Opcode_name[423:431],
-	88:  _Opcode_name[431:438],
-	89:  _Opcode_name[438:445],
-	90:  _Opcode_name[445:452],
-	91:  _Opcode_name[452:459],
-	92:  _Opcode_name[459:466],
-	93:  _Opcode_name[466:473],
-	94:  _Opcode_name[473:480],
-	95:  _Opcode_name[480:486],
-	96:  _Opcode_name[486:493],
-	97:  _Opcode_name[493:500],
-	98:  _Opcode_name[500:507],
-	99:  _Opcode_name[507:514],
-	100: _Opcode_name[514:521],
-	101: _Opcode_name[521:528],
-	102: _Opcode_name[528:535],
-	103: _Opcode_name[535:541],
-	104: _Opcode_name[541:547],
-	105: _Opcode_name[547:553],
-	106: _Opcode_name[553:559],
-	107: _Opcode_name[559:565],
-	108: _Opcode_name[565:571],
-	109: _Opcode_name[571:577],
-	110: _Opcode_name[577:583],
-	111: _Opcode_name[583:588],
-	112: _Opcode_name[588:594],
-	113: _Opcode_name[594:600],
-	114: _Opcode_name[600:606],
-	115: _Opcode_name[606:612],
-	116: _Opcode_name[612:618],
-	117: _Opcode_name[618:624],
-	118: _Opcode_name[624:630],
-	119: _Opcode_name[630:635],
-	120: _Opcode_name[635:641],
-	121: _Opcode_name[641:647],
-	122: _Opcode_name[647:653],
-	123: _Opcode_name[653:659],
-	124: _Opcode_name[659:665],
-	125: _Opcode_name[665:671],
-	126: _Opcode_name[671:677],
-	127: _Opcode_name[677:682],
-	128: _Opcode_name[682:688],
-	129: _Opcode_name[688:694],
-	130: _Opcode_name[694:700],
-	131: _Opcode_name[700:706],
-	132: _Opcode_name[706:712],
-	133: _Opcode_name[712:718],
-	134: _Opcode_name[718:724],
-	135: _Opcode_name[724:729],
-	136: _Opcode_name[729:738],
-	137: _Opcode_name[738:744],
-	139: _Opcode_name[744:747],
-	140: _Opcode_name[747:753],
-	141: _Opcode_name[753:757],
-	142: _Opcode_name[757:762],
-	144: _Opcode_name[762:768],
-	145: _Opcode_name[768:771],
-	146: _Opcode_name[771:773],
-	147: _Opcode_name[773:776],
-	151: _Opcode_name[776:781],
-	152: _Opcode_name[781:789],
-	153: _Opcode_name[789:793],
-	154: _Opcode_name[793:796],
-	155: _Opcode_name[796:802],
-	156: _Opcode_name[802:805],
-	157: _Opcode_name[805:808],
-	158: _Opcode_name[808:811],
-	159: _Opcode_name[811:814],
-	160: _Opcode_name[814:817],
-	161: _Opcode_name[817:820],
-	162: _Opcode_name[820:823],
-	168: _Opcode_name[823:826],
-	169: _Opcode_name[826:829],
-	170: _Opcode_name[829:832],
-	171: _Opcode_name[832:839],
-	172: _Opcode_name[839:845],
-	177: _Opcode_name[845:847],
-	179: _Opcode_name[847:855],
-	180: _Opcode_name[855:866],
-	181: _Opcode_name[866:868],
-	182: _Opcode_name[868:871],
-	183: _Opcode_name[871:873],
-	184: _Opcode_name[873:876],
-	185: _Opcode_name[876:879],
-	186: _Opcode_name[879:882],
-	187: _Opcode_name[882:888],
-	192: _Opcode_name[888:892],
-	193: _Opcode_name[892:898],
-	194: _Opcode_name[898:907],
-	195: _Opcode_name[907:915],
-	196: _Opcode_name[915:924],
-	197: _Opcode_name[924:934],
-	198: _Opcode_name[934:943],
-	200: _Opcode_name[943:949],
-	202: _Opcode_name[949:953],
-	203: _Opcode_name[953:959],
-	204: _Opcode_name[959:963],
-	205: _Opcode_name[963:969],
-	206: _Opcode_name[969:977],
-	207: _Opcode_name[977:983],
-	208: _Opcode_name[983:990],
-	209: _Opcode_name[990:1002],
-	210: _Opcode_name[1002:1008],
-	211: _Opcode_name[1008:1018],
-	216: _Opcode_name[1018:1024],
-	217: _Opcode_name[1024:1030],
-	219: _Opcode_name[1030:1037],
+	35:  _Opcode_name[199:204],
+	36:  _Opcode_name[204:209],
+	37:  _Opcode_name[209:216],
+	38:  _Opcode_name[216:224],
+	39:  _Opcode_name[224:234],
+	40:  _Opcode_name[234:239],
+	41:  _Opcode_name[239:246],
+	42:  _Opcode_name[246:251],
+	43:  _Opcode_name[251:258],
+	44:  _Opcode_name[258:263],
+	45:  _Opcode_name[263:270],
+	46:  _Opcode_name[270:275],
+	47:  _Opcode_name[275:282],
+	48:  _Opcode_name[282:287],
+	49:  _Opcode_name[287:294],
+	50:  _Opcode_name[294:299],
+	51:  _Opcode_name[299:306],
+	52:  _Opcode_name[306:310],
+	53:  _Opcode_name[310:316],
+	54:  _Opcode_name[316:321],
+	55:  _Opcode_name[321:326],
+	56:  _Opcode_name[326:332],
+	58:  _Opcode_name[332:337],
+	64:  _Opcode_name[337:340],
+	65:  _Opcode_name[340:347],
+	67:  _Opcode_name[347:352],
+	69:  _Opcode_name[352:356],
+	70:  _Opcode_name[356:359],
+	72:  _Opcode_name[359:364],
+	73:  _Opcode_name[364:369],
+	74:  _Opcode_name[369:372],
+	75:  _Opcode_name[372:376],
+	77:  _Opcode_name[376:380],
+	78:  _Opcode_name[380:384],
+	80:  _Opcode_name[384:388],
+	81:  _Opcode_name[388:391],
+	82:  _Opcode_name[391:395],
+	83:  _Opcode_name[395:403],
+	84:  _Opcode_name[403:411],
+	85:  _Opcode_name[411:419],
+	86:  _Opcode_name[419:428],
+	87:  _Opcode_name[428:436],
+	88:  _Opcode_name[436:443],
+	89:  _Opcode_name[443:450],
+	90:  _Opcode_name[450:457],
+	91:  _Opcode_name[457:464],
+	92:  _Opcode_name[464:471],
+	93:  _Opcode_name[471:478],
+	94:  _Opcode_name[478:485],
+	95:  _Opcode_name[485:491],
+	96:  _Opcode_name[491:498],
+	97:  _Opcode_name[498:505],
+	98:  _Opcode_name[505:512],
+	99:  _Opcode_name[512:519],
+	100: _Opcode_name[519:526],
+	101: _Opcode_name[526:533],
+	102: _Opcode_name[533:540],
+	103: _Opcode_name[540:546],
+	104: _Opcode_name[546:552],
+	105: _Opcode_name[552:558],
+	106: _Opcode_name[558:564],
+	107: _Opcode_name[564:570],
+	108: _Opcode_name[570:576],
+	109: _Opcode_name[576:582],
+	110: _Opcode_name[582:588],
+	111: _Opcode_name[588:593],
+	112: _Opcode_name[593:599],
+	113: _Opcode_name[599:605],
+	114: _Opcode_name[605:611],
+	115: _Opcode_name[611:617],
+	116: _Opcode_name[617:623],
+	117: _Opcode_name[623:629],
+	118: _Opcode_name[629:635],
+	119: _Opcode_name[635:640],
+	120: _Opcode_name[640:646],
+	121: _Opcode_name[646:652],
+	122: _Opcode_name[652:658],
+	123: _Opcode_name[658:664],
+	124: _Opcode_name[664:670],
+	125: _Opcode_name[670:676],
+	126: _Opcode_name[676:682],
+	127: _Opcode_name[682:687],
+	128: _Opcode_name[687:693],
+	129: _Opcode_name[693:699],
+	130: _Opcode_name[699:705],
+	131: _Opcode_name[705:711],
+	132: _Opcode_name[711:717],
+	133: _Opcode_name[717:723],
+	134: _Opcode_name[723:729],
+	135: _Opcode_name[729:734],
+	136: _Opcode_name[734:743],
+	137: _Opcode_name[743:749],
+	139: _Opcode_name[749:752],
+	140: _Opcode_name[752:758],
+	141: _Opcode_name[758:762],
+	142: _Opcode_name[762:767],
+	144: _Opcode_name[767:773],
+	145: _Opcode_name[773:776],
+	146: _Opcode_name[776:778],
+	147: _Opcode_name[778:781],
+	151: _Opcode_name[781:786],
+	152: _Opcode_name[786:794],
+	153: _Opcode_name[794:798],
+	154: _Opcode_name[798:801],
+	155: _Opcode_name[801:807],
+	156: _Opcode_name[807:810],
+	157: _Opcode_name[810:813],
+	158: _Opcode_name[813:816],
+	159: _Opcode_name[816:819],
+	160: _Opcode_name[819:822],
+	161: _Opcode_name[822:825],
+	162: _Opcode_name[825:828],
+	168: _Opcode_name[828:831],
+	169: _Opcode_name[831:834],
+	170: _Opcode_name[834:837],
+	171: _Opcode_name[837:844],
+	172: _Opcode_name[844:850],
+	177: _Opcode_name[850:852],
+	179: _Opcode_name[852:860],
+	180: _Opcode_name[860:871],
+	181: _Opcode_name[871:873],
+	182: _Opcode_name[873:876],
+	183: _Opcode_name[876:878],
+	184: _Opcode_name[878:881],
+	185: _Opcode_name[881:884],
+	186: _Opcode_name[884:887],
+	187: _Opcode_name[887:893],
+	192: _Opcode_name[893:897],
+	193: _Opcode_name[897:903],
+	194: _Opcode_name[903:912],
+	195: _Opcode_name[912:920],
+	196: _Opcode_name[920:930],
+	197: _Opcode_name[930:940],
+	198: _Opcode_name[940:949],
+	200: _Opcode_name[949:955],
+	202: _Opcode_name[955:959],
+	203: _Opcode_name[959:965],
+	204: _Opcode_name[965:969],
+	205: _Opcode_name[969:975],
+	206: _Opcode_name[975:983],
+	207: _Opcode_name[983:989],
+	208: _Opcode_name[989:996],
+	209: _Opcode_name[996:1008],
+	210: _Opcode_name[1008:1014],
+	211: _Opcode_name[1014:1024],
+	216: _Opcode_name[1024:1030],
+	217: _Opcode_name[1030:1036],
+	219: _Opcode_name[1036:1043],
 }

 func (i Opcode) String() string {
--- a/pkg/vm/opcode/opcode_test.go
+++ b/pkg/vm/opcode/opcode_test.go
@ -4,6 +4,7 @@ import (
 	"testing"

 	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
 )

 // Nothing more to test here, really.
@ -18,3 +19,12 @@ func TestStringer(t *testing.T) {
 		assert.Equal(t, s, o.String())
 	}
 }
+
+func TestFromString(t *testing.T) {
+	_, err := FromString("abcdef")
+	require.Error(t, err)
+
+	op, err := FromString(MUL.String())
+	require.NoError(t, err)
+	require.Equal(t, MUL, op)
+}
--- a/pkg/vm/stack_item.go
+++ b/pkg/vm/stack_item.go
@ -225,7 +225,9 @@ func (i *StructItem) Convert(typ StackItemType) (StackItem, error) {
 	case StructT:
 		return i, nil
 	case ArrayT:
-		return NewArrayItem(i.value), nil
+		arr := make([]StackItem, len(i.value))
+		copy(arr, i.value)
+		return NewArrayItem(arr), nil
 	case BooleanT:
 		return NewBoolItem(i.Bool()), nil
 	default:
@ -641,7 +643,9 @@ func (i *ArrayItem) Convert(typ StackItemType) (StackItem, error) {
 	case ArrayT:
 		return i, nil
 	case StructT:
-		return NewStructItem(i.value), nil
+		arr := make([]StackItem, len(i.value))
+		copy(arr, i.value)
+		return NewStructItem(arr), nil
 	case BooleanT:
 		return NewBoolItem(i.Bool()), nil
 	default:
--- a/pkg/vm/vm.go
+++ b/pkg/vm/vm.go
@ -338,7 +338,7 @@ func (v *VM) Run() error {
 		// check for breakpoint before executing the next instruction
 		ctx := v.Context()
 		if ctx != nil && ctx.atBreakPoint() {
-			v.state |= breakState
+			v.state = breakState
 		}
 		switch {
 		case v.state.HasFlag(faultState):
@ -376,7 +376,7 @@ func (v *VM) StepInto() error {
 	ctx := v.Context()

 	if ctx == nil {
-		v.state |= haltState
+		v.state = haltState
 	}

 	if v.HasStopped() {
@ -518,17 +518,14 @@ func (v *VM) execute(ctx *Context, op opcode.Opcode, parameter []byte) (err erro
 	}

 	switch op {
-	case opcode.PUSHM1, opcode.PUSH1, opcode.PUSH2, opcode.PUSH3,
+	case opcode.PUSHM1, opcode.PUSH0, opcode.PUSH1, opcode.PUSH2, opcode.PUSH3,
 		opcode.PUSH4, opcode.PUSH5, opcode.PUSH6, opcode.PUSH7,
 		opcode.PUSH8, opcode.PUSH9, opcode.PUSH10, opcode.PUSH11,
 		opcode.PUSH12, opcode.PUSH13, opcode.PUSH14, opcode.PUSH15,
 		opcode.PUSH16:
-		val := int(op) - int(opcode.PUSH1) + 1
+		val := int(op) - int(opcode.PUSH0)
 		v.estack.PushVal(val)

-	case opcode.PUSH0:
-		v.estack.PushVal([]byte{})
-
 	case opcode.PUSHDATA1, opcode.PUSHDATA2, opcode.PUSHDATA4:
 		v.estack.PushVal(parameter)

@ -697,7 +694,7 @@ func (v *VM) execute(ctx *Context, op opcode.Opcode, parameter []byte) (err erro
 		}
 		s := v.estack.Pop().Bytes()
 		if t := len(s); l > t {
-			l = t
+			panic("size is too big")
 		}
 		v.estack.PushVal(NewBufferItem(s[:l]))

@ -984,46 +981,28 @@ func (v *VM) execute(ctx *Context, op opcode.Opcode, parameter []byte) (err erro

 	case opcode.NEWARRAY, opcode.NEWARRAYT:
 		item := v.estack.Pop()
-		switch t := item.value.(type) {
-		case *StructItem:
-			arr := make([]StackItem, len(t.value))
-			copy(arr, t.value)
-			v.estack.PushVal(&ArrayItem{arr})
-		case *ArrayItem:
-			v.estack.PushVal(t)
-		default:
-			n := item.BigInt().Int64()
-			if n > MaxArraySize {
-				panic("too long array")
-			}
-			typ := BooleanT
-			if op == opcode.NEWARRAYT {
-				typ = StackItemType(parameter[0])
-			}
-			items := makeArrayOfType(int(n), typ)
-			v.estack.PushVal(&ArrayItem{items})
+		n := item.BigInt().Int64()
+		if n > MaxArraySize {
+			panic("too long array")
 		}
+		typ := AnyT
+		if op == opcode.NEWARRAYT {
+			typ = StackItemType(parameter[0])
+		}
+		items := makeArrayOfType(int(n), typ)
+		v.estack.PushVal(&ArrayItem{items})

 	case opcode.NEWSTRUCT0:
 		v.estack.PushVal(&StructItem{[]StackItem{}})

 	case opcode.NEWSTRUCT:
 		item := v.estack.Pop()
-		switch t := item.value.(type) {
-		case *ArrayItem:
-			arr := make([]StackItem, len(t.value))
-			copy(arr, t.value)
-			v.estack.PushVal(&StructItem{arr})
-		case *StructItem:
-			v.estack.PushVal(t)
-		default:
-			n := item.BigInt().Int64()
-			if n > MaxArraySize {
-				panic("too long struct")
-			}
-			items := makeArrayOfType(int(n), BooleanT)
-			v.estack.PushVal(&StructItem{items})
+		n := item.BigInt().Int64()
+		if n > MaxArraySize {
+			panic("too long struct")
 		}
+		items := makeArrayOfType(int(n), AnyT)
+		v.estack.PushVal(&StructItem{items})

 	case opcode.APPEND:
 		itemElem := v.estack.Pop()
--- a/pkg/vm/vm_test.go
+++ b/pkg/vm/vm_test.go
@ -372,7 +372,7 @@ func appendBigStruct(size uint16) []opcode.Opcode {
 	return append(prog,
 		opcode.INITSSLOT, 1,
 		opcode.PUSHINT16, opcode.Opcode(size), opcode.Opcode(size>>8), // LE
-		opcode.PACK, opcode.NEWSTRUCT,
+		opcode.PACK, opcode.CONVERT, opcode.Opcode(StructT),
 		opcode.STSFLD0, opcode.LDSFLD0,
 		opcode.DUP,
 		opcode.PUSH0, opcode.NEWARRAY,
@ -401,20 +401,19 @@ func TestStackLimit(t *testing.T) {
 		{opcode.NEWARRAY, 3}, // array + 2 items
 		{opcode.STSFLD0, 3},
 		{opcode.LDSFLD0, 4},
-		{opcode.NEWSTRUCT, 6}, // all items are copied
-		{opcode.NEWMAP, 7},
-		{opcode.DUP, 8},
-		{opcode.PUSH2, 9},
-		{opcode.LDSFLD0, 10},
-		{opcode.SETITEM, 8}, // -3 items and 1 new element in map
-		{opcode.DUP, 9},
-		{opcode.PUSH2, 10},
-		{opcode.LDSFLD0, 11},
-		{opcode.SETITEM, 8}, // -3 items and no new elements in map
-		{opcode.DUP, 9},
-		{opcode.PUSH2, 10},
-		{opcode.REMOVE, 7}, // as we have right after NEWMAP
-		{opcode.DROP, 6},   // DROP map with no elements
+		{opcode.NEWMAP, 5},
+		{opcode.DUP, 6},
+		{opcode.PUSH2, 7},
+		{opcode.LDSFLD0, 8},
+		{opcode.SETITEM, 6}, // -3 items and 1 new element in map
+		{opcode.DUP, 7},
+		{opcode.PUSH2, 8},
+		{opcode.LDSFLD0, 9},
+		{opcode.SETITEM, 6}, // -3 items and no new elements in map
+		{opcode.DUP, 7},
+		{opcode.PUSH2, 8},
+		{opcode.REMOVE, 5}, // as we have right after NEWMAP
+		{opcode.DROP, 4},   // DROP map with no elements
 	}

 	prog := make([]opcode.Opcode, len(expected)+2)
@ -1188,45 +1187,37 @@ func TestNEWARRAYArray(t *testing.T) {
 	prog := makeProgram(opcode.NEWARRAY)
 	t.Run("ByteArray", getTestFuncForVM(prog, NewArrayItem([]StackItem{}), []byte{}))
 	t.Run("BadSize", getTestFuncForVM(prog, nil, MaxArraySize+1))
-	t.Run("Integer", getTestFuncForVM(prog, []StackItem{NewBoolItem(false)}, 1))
-
-	arr := []StackItem{makeStackItem(42)}
-	t.Run("Array", getTestFuncForVM(prog, arr, arr))
-	t.Run("Struct", getTestFuncForVM(prog, arr, NewStructItem(arr)))
+	t.Run("Integer", getTestFuncForVM(prog, []StackItem{NullItem{}}, 1))
 }

-func testNEWARRAYIssue437(t *testing.T, i1, i2 opcode.Opcode, appended bool) {
+func testNEWARRAYIssue437(t *testing.T, i1 opcode.Opcode, t2 StackItemType, appended bool) {
 	prog := makeProgram(
 		opcode.PUSH2, i1,
 		opcode.DUP, opcode.PUSH3, opcode.APPEND,
 		opcode.INITSSLOT, 1,
-		opcode.STSFLD0, opcode.LDSFLD0, i2,
+		opcode.STSFLD0, opcode.LDSFLD0, opcode.CONVERT, opcode.Opcode(t2),
 		opcode.DUP, opcode.PUSH4, opcode.APPEND,
 		opcode.LDSFLD0, opcode.PUSH5, opcode.APPEND)
-	vm := load(prog)
-	vm.Run()

-	arr := makeArrayOfType(4, BooleanT)
+	arr := makeArrayOfType(4, AnyT)
 	arr[2] = makeStackItem(3)
 	arr[3] = makeStackItem(4)
 	if appended {
 		arr = append(arr, makeStackItem(5))
 	}

-	assert.Equal(t, false, vm.HasFailed())
-	assert.Equal(t, 1, vm.estack.Len())
-	if i2 == opcode.NEWARRAY {
-		assert.Equal(t, &ArrayItem{arr}, vm.estack.Pop().value)
+	if t2 == ArrayT {
+		runWithArgs(t, prog, &ArrayItem{arr})
 	} else {
-		assert.Equal(t, &StructItem{arr}, vm.estack.Pop().value)
+		runWithArgs(t, prog, &StructItem{arr})
 	}
 }

 func TestNEWARRAYIssue437(t *testing.T) {
-	t.Run("Array+Array", func(t *testing.T) { testNEWARRAYIssue437(t, opcode.NEWARRAY, opcode.NEWARRAY, true) })
-	t.Run("Struct+Struct", func(t *testing.T) { testNEWARRAYIssue437(t, opcode.NEWSTRUCT, opcode.NEWSTRUCT, true) })
-	t.Run("Array+Struct", func(t *testing.T) { testNEWARRAYIssue437(t, opcode.NEWARRAY, opcode.NEWSTRUCT, false) })
-	t.Run("Struct+Array", func(t *testing.T) { testNEWARRAYIssue437(t, opcode.NEWSTRUCT, opcode.NEWARRAY, false) })
+	t.Run("Array+Array", func(t *testing.T) { testNEWARRAYIssue437(t, opcode.NEWARRAY, ArrayT, true) })
+	t.Run("Struct+Struct", func(t *testing.T) { testNEWARRAYIssue437(t, opcode.NEWSTRUCT, StructT, true) })
+	t.Run("Array+Struct", func(t *testing.T) { testNEWARRAYIssue437(t, opcode.NEWARRAY, StructT, false) })
+	t.Run("Struct+Array", func(t *testing.T) { testNEWARRAYIssue437(t, opcode.NEWSTRUCT, ArrayT, false) })
 }

 func TestNEWARRAYT(t *testing.T) {
@ -1247,11 +1238,7 @@ func TestNEWSTRUCT(t *testing.T) {
 	prog := makeProgram(opcode.NEWSTRUCT)
 	t.Run("ByteArray", getTestFuncForVM(prog, NewStructItem([]StackItem{}), []byte{}))
 	t.Run("BadSize", getTestFuncForVM(prog, nil, MaxArraySize+1))
-	t.Run("Integer", getTestFuncForVM(prog, NewStructItem([]StackItem{NewBoolItem(false)}), 1))
-
-	arr := []StackItem{makeStackItem(42)}
-	t.Run("Array", getTestFuncForVM(prog, NewStructItem(arr), NewArrayItem(arr)))
-	t.Run("Struct", getTestFuncForVM(prog, NewStructItem(arr), NewStructItem(arr)))
+	t.Run("Integer", getTestFuncForVM(prog, NewStructItem([]StackItem{NullItem{}}), 1))
 }

 func TestAPPEND(t *testing.T) {
@ -1827,7 +1814,7 @@ func TestLEFT(t *testing.T) {
 	t.Run("NoString", getTestFuncForVM(prog, nil, 2))
 	t.Run("NegativeLen", getTestFuncForVM(prog, nil, "abcdef", -1))
 	t.Run("Good", getTestFuncForVM(prog, NewBufferItem([]byte("ab")), "abcdef", 2))
-	t.Run("GoodBigLen", getTestFuncForVM(prog, NewBufferItem([]byte("abcdef")), "abcdef", 8))
+	t.Run("BadBigLen", getTestFuncForVM(prog, nil, "abcdef", 8))
 }

 func TestRIGHT(t *testing.T) {
@ -1903,14 +1890,12 @@ func TestREVERSEITEMS(t *testing.T) {
 	t.Run("Buffer", getTestFuncForVM(prog, NewBufferItem([]byte{3, 2, 1}), NewBufferItem([]byte{1, 2, 3})))
 }

-func testREVERSEITEMSIssue437(t *testing.T, i1, i2 opcode.Opcode, reversed bool) {
+func testREVERSEITEMSIssue437(t *testing.T, i1 opcode.Opcode, t2 StackItemType, reversed bool) {
 	prog := makeProgram(
 		opcode.PUSH0, i1,
 		opcode.DUP, opcode.PUSH1, opcode.APPEND,
 		opcode.DUP, opcode.PUSH2, opcode.APPEND,
-		opcode.DUP, i2, opcode.REVERSEITEMS)
-	vm := load(prog)
-	vm.Run()
+		opcode.DUP, opcode.CONVERT, opcode.Opcode(t2), opcode.REVERSEITEMS)

 	arr := make([]StackItem, 2)
 	if reversed {
@ -1920,20 +1905,19 @@ func testREVERSEITEMSIssue437(t *testing.T, i1, i2 opcode.Opcode, reversed bool)
 		arr[0] = makeStackItem(1)
 		arr[1] = makeStackItem(2)
 	}
-	assert.Equal(t, false, vm.HasFailed())
-	assert.Equal(t, 1, vm.estack.Len())
+
 	if i1 == opcode.NEWARRAY {
-		assert.Equal(t, &ArrayItem{arr}, vm.estack.Pop().value)
+		runWithArgs(t, prog, &ArrayItem{arr})
 	} else {
-		assert.Equal(t, &StructItem{arr}, vm.estack.Pop().value)
+		runWithArgs(t, prog, &StructItem{arr})
 	}
 }

 func TestREVERSEITEMSIssue437(t *testing.T) {
-	t.Run("Array+Array", func(t *testing.T) { testREVERSEITEMSIssue437(t, opcode.NEWARRAY, opcode.NEWARRAY, true) })
-	t.Run("Struct+Struct", func(t *testing.T) { testREVERSEITEMSIssue437(t, opcode.NEWSTRUCT, opcode.NEWSTRUCT, true) })
-	t.Run("Array+Struct", func(t *testing.T) { testREVERSEITEMSIssue437(t, opcode.NEWARRAY, opcode.NEWSTRUCT, false) })
-	t.Run("Struct+Array", func(t *testing.T) { testREVERSEITEMSIssue437(t, opcode.NEWSTRUCT, opcode.NEWARRAY, false) })
+	t.Run("Array+Array", func(t *testing.T) { testREVERSEITEMSIssue437(t, opcode.NEWARRAY, ArrayT, true) })
+	t.Run("Struct+Struct", func(t *testing.T) { testREVERSEITEMSIssue437(t, opcode.NEWSTRUCT, StructT, true) })
+	t.Run("Array+Struct", func(t *testing.T) { testREVERSEITEMSIssue437(t, opcode.NEWARRAY, StructT, false) })
+	t.Run("Struct+Array", func(t *testing.T) { testREVERSEITEMSIssue437(t, opcode.NEWSTRUCT, ArrayT, false) })
 }

 func TestREVERSEITEMSGoodOneElem(t *testing.T) {
@ -2471,7 +2455,9 @@ func makeProgram(opcodes ...opcode.Opcode) []byte {

 func load(prog []byte) *VM {
 	vm := New()
-	vm.LoadScript(prog)
+	if len(prog) != 0 {
+		vm.LoadScript(prog)
+	}
 	return vm
 }