core: move contract-related interop code into appropriate package

And move one of the tests with it.

pkg/core/interop/contract/account.go

@@ -0,0 +1,71 @@
+package contract
+
+import (
+	"crypto/elliptic"
+	"errors"
+	"math"
+
+	"github.com/nspcc-dev/neo-go/pkg/config"
+	"github.com/nspcc-dev/neo-go/pkg/core/fee"
+	"github.com/nspcc-dev/neo-go/pkg/core/interop"
+	"github.com/nspcc-dev/neo-go/pkg/crypto/hash"
+	"github.com/nspcc-dev/neo-go/pkg/crypto/keys"
+	"github.com/nspcc-dev/neo-go/pkg/smartcontract"
+	"github.com/nspcc-dev/neo-go/pkg/vm/stackitem"
+)
+
+// CreateMultisigAccount calculates multisig contract scripthash for a
+// given m and a set of public keys.
+func CreateMultisigAccount(ic *interop.Context) error {
+	m := ic.VM.Estack().Pop().BigInt()
+	mu64 := m.Uint64()
+	if !m.IsUint64() || mu64 > math.MaxInt32 {
+		return errors.New("m must be positive and fit int32")
+	}
+	arr := ic.VM.Estack().Pop().Array()
+	pubs := make(keys.PublicKeys, len(arr))
+	for i, pk := range arr {
+		p, err := keys.NewPublicKeyFromBytes(pk.Value().([]byte), elliptic.P256())
+		if err != nil {
+			return err
+		}
+		pubs[i] = p
+	}
+	var invokeFee int64
+	if ic.IsHardforkEnabled(config.HFAspidochelone) {
+		invokeFee = fee.ECDSAVerifyPrice * int64(len(pubs))
+	} else {
+		invokeFee = 1 << 8
+	}
+	invokeFee *= ic.BaseExecFee()
+	if !ic.VM.AddGas(invokeFee) {
+		return errors.New("gas limit exceeded")
+	}
+	script, err := smartcontract.CreateMultiSigRedeemScript(int(mu64), pubs)
+	if err != nil {
+		return err
+	}
+	ic.VM.Estack().PushItem(stackitem.NewByteArray(hash.Hash160(script).BytesBE()))
+	return nil
+}
+
+// CreateStandardAccount calculates contract scripthash for a given public key.
+func CreateStandardAccount(ic *interop.Context) error {
+	h := ic.VM.Estack().Pop().Bytes()
+	p, err := keys.NewPublicKeyFromBytes(h, elliptic.P256())
+	if err != nil {
+		return err
+	}
+	var invokeFee int64
+	if ic.IsHardforkEnabled(config.HFAspidochelone) {
+		invokeFee = fee.ECDSAVerifyPrice
+	} else {
+		invokeFee = 1 << 8
+	}
+	invokeFee *= ic.BaseExecFee()
+	if !ic.VM.AddGas(invokeFee) {
+		return errors.New("gas limit exceeded")
+	}
+	ic.VM.Estack().PushItem(stackitem.NewByteArray(p.GetScriptHash().BytesBE()))
+	return nil
+}

pkg/core/interop/contract/call.go

@@ -3,6 +3,7 @@ package contract
 import (
 	"errors"
 	"fmt"
+	"math/big"
 	"strings"
 
 	"github.com/nspcc-dev/neo-go/pkg/core/dao"
@@ -172,3 +173,9 @@ func CallFromNative(ic *interop.Context, caller util.Uint160, cs *state.Contract
 	}
 	return nil
 }
+
+// GetCallFlags returns current context calling flags.
+func GetCallFlags(ic *interop.Context) error {
+	ic.VM.Estack().PushItem(stackitem.NewBigInteger(big.NewInt(int64(ic.VM.Context().GetCallFlags()))))
+	return nil
+}

pkg/core/interop/contract/call_test.go

@@ -0,0 +1,25 @@
+package contract_test
+
+import (
+	"math/big"
+	"testing"
+
+	"github.com/nspcc-dev/neo-go/pkg/core/block"
+	"github.com/nspcc-dev/neo-go/pkg/core/interop/contract"
+	"github.com/nspcc-dev/neo-go/pkg/core/transaction"
+	"github.com/nspcc-dev/neo-go/pkg/neotest/chain"
+	"github.com/nspcc-dev/neo-go/pkg/smartcontract/callflag"
+	"github.com/nspcc-dev/neo-go/pkg/smartcontract/trigger"
+	"github.com/nspcc-dev/neo-go/pkg/util"
+	"github.com/nspcc-dev/neo-go/pkg/vm/opcode"
+	"github.com/stretchr/testify/require"
+)
+
+func TestGetCallFlags(t *testing.T) {
+	bc, _ := chain.NewSingle(t)
+	ic := bc.GetTestVM(trigger.Application, &transaction.Transaction{}, &block.Block{})
+
+	ic.VM.LoadScriptWithHash([]byte{byte(opcode.RET)}, util.Uint160{1, 2, 3}, callflag.All)
+	require.NoError(t, contract.GetCallFlags(ic))
+	require.Equal(t, int64(callflag.All), ic.VM.Estack().Pop().Value().(*big.Int).Int64())
+}

pkg/core/interop_system.go

@@ -2,23 +2,15 @@ package core
 
 import (
 	"context"
-	"crypto/elliptic"
 	"errors"
 	"fmt"
-	"math"
-	"math/big"
 
-	"github.com/nspcc-dev/neo-go/pkg/config"
 	"github.com/nspcc-dev/neo-go/pkg/core/block"
-	"github.com/nspcc-dev/neo-go/pkg/core/fee"
 	"github.com/nspcc-dev/neo-go/pkg/core/interop"
 	istorage "github.com/nspcc-dev/neo-go/pkg/core/interop/storage"
 	"github.com/nspcc-dev/neo-go/pkg/core/native"
 	"github.com/nspcc-dev/neo-go/pkg/core/storage"
 	"github.com/nspcc-dev/neo-go/pkg/core/transaction"
-	"github.com/nspcc-dev/neo-go/pkg/crypto/hash"
-	"github.com/nspcc-dev/neo-go/pkg/crypto/keys"
-	"github.com/nspcc-dev/neo-go/pkg/smartcontract"
 	"github.com/nspcc-dev/neo-go/pkg/vm/stackitem"
 )
 
@@ -206,65 +198,3 @@ func storageFind(ic *interop.Context) error {
 
 	return nil
 }
-
-// contractCreateMultisigAccount calculates multisig contract scripthash for a
-// given m and a set of public keys.
-func contractCreateMultisigAccount(ic *interop.Context) error {
-	m := ic.VM.Estack().Pop().BigInt()
-	mu64 := m.Uint64()
-	if !m.IsUint64() || mu64 > math.MaxInt32 {
-		return errors.New("m must be positive and fit int32")
-	}
-	arr := ic.VM.Estack().Pop().Array()
-	pubs := make(keys.PublicKeys, len(arr))
-	for i, pk := range arr {
-		p, err := keys.NewPublicKeyFromBytes(pk.Value().([]byte), elliptic.P256())
-		if err != nil {
-			return err
-		}
-		pubs[i] = p
-	}
-	var invokeFee int64
-	if ic.IsHardforkEnabled(config.HFAspidochelone) {
-		invokeFee = fee.ECDSAVerifyPrice * int64(len(pubs))
-	} else {
-		invokeFee = 1 << 8
-	}
-	invokeFee *= ic.BaseExecFee()
-	if !ic.VM.AddGas(invokeFee) {
-		return errors.New("gas limit exceeded")
-	}
-	script, err := smartcontract.CreateMultiSigRedeemScript(int(mu64), pubs)
-	if err != nil {
-		return err
-	}
-	ic.VM.Estack().PushItem(stackitem.NewByteArray(hash.Hash160(script).BytesBE()))
-	return nil
-}
-
-// contractCreateStandardAccount calculates contract scripthash for a given public key.
-func contractCreateStandardAccount(ic *interop.Context) error {
-	h := ic.VM.Estack().Pop().Bytes()
-	p, err := keys.NewPublicKeyFromBytes(h, elliptic.P256())
-	if err != nil {
-		return err
-	}
-	var invokeFee int64
-	if ic.IsHardforkEnabled(config.HFAspidochelone) {
-		invokeFee = fee.ECDSAVerifyPrice
-	} else {
-		invokeFee = 1 << 8
-	}
-	invokeFee *= ic.BaseExecFee()
-	if !ic.VM.AddGas(invokeFee) {
-		return errors.New("gas limit exceeded")
-	}
-	ic.VM.Estack().PushItem(stackitem.NewByteArray(p.GetScriptHash().BytesBE()))
-	return nil
-}
-
-// contractGetCallFlags returns current context calling flags.
-func contractGetCallFlags(ic *interop.Context) error {
-	ic.VM.Estack().PushItem(stackitem.NewBigInteger(big.NewInt(int64(ic.VM.Context().GetCallFlags()))))
-	return nil
-}

pkg/core/interop_system_core_test.go

@@ -706,14 +706,6 @@ func TestContractCall(t *testing.T) {
 	})
 }
 
-func TestContractGetCallFlags(t *testing.T) {
-	v, ic, _ := createVM(t)
-
-	v.LoadScriptWithHash([]byte{byte(opcode.RET)}, util.Uint160{1, 2, 3}, callflag.All)
-	require.NoError(t, contractGetCallFlags(ic))
-	require.Equal(t, int64(callflag.All), v.Estack().Pop().Value().(*big.Int).Int64())
-}
-
 func TestRuntimeCheckWitness(t *testing.T) {
 	_, ic, bc := createVM(t)
 

pkg/core/interops.go

@@ -33,9 +33,9 @@ var systemInterops = []interop.Function{
 	{Name: interopnames.SystemContractCall, Func: contract.Call, Price: 1 << 15,
 		RequiredFlags: callflag.ReadStates | callflag.AllowCall, ParamCount: 4},
 	{Name: interopnames.SystemContractCallNative, Func: native.Call, Price: 0, ParamCount: 1},
-	{Name: interopnames.SystemContractCreateMultisigAccount, Func: contractCreateMultisigAccount, Price: 0, ParamCount: 2},
+	{Name: interopnames.SystemContractCreateMultisigAccount, Func: contract.CreateMultisigAccount, Price: 0, ParamCount: 2},
-	{Name: interopnames.SystemContractCreateStandardAccount, Func: contractCreateStandardAccount, Price: 0, ParamCount: 1},
+	{Name: interopnames.SystemContractCreateStandardAccount, Func: contract.CreateStandardAccount, Price: 0, ParamCount: 1},
-	{Name: interopnames.SystemContractGetCallFlags, Func: contractGetCallFlags, Price: 1 << 10},
+	{Name: interopnames.SystemContractGetCallFlags, Func: contract.GetCallFlags, Price: 1 << 10},
 	{Name: interopnames.SystemContractNativeOnPersist, Func: native.OnPersist, Price: 0, RequiredFlags: callflag.States},
 	{Name: interopnames.SystemContractNativePostPersist, Func: native.PostPersist, Price: 0, RequiredFlags: callflag.States},
 	{Name: interopnames.SystemCryptoCheckMultisig, Func: crypto.ECDSASecp256r1CheckMultisig, Price: 0, ParamCount: 2},