[#822] moprh/event: Add parsers from Op struct

Signed-off-by: Pavel Karpy <carpawell@nspcc.ru>
This commit is contained in:
Pavel Karpy 2021-09-10 15:29:13 +03:00 committed by Alex Vanin
parent 61b4baf736
commit 4f3de1a9af
2 changed files with 112 additions and 1 deletions

View file

@ -1,6 +1,11 @@
package event
import "github.com/nspcc-dev/neo-go/pkg/vm/opcode"
import (
"fmt"
"github.com/nspcc-dev/neo-go/pkg/encoding/bigint"
"github.com/nspcc-dev/neo-go/pkg/vm/opcode"
)
// Op is wrapper over Neo VM's opcode
// and its parameter.
@ -19,3 +24,27 @@ func (o Op) Code() opcode.Opcode {
func (o Op) Param() []byte {
return o.param
}
// BytesFromOpcode tries to retrieve bytes from Op.
func BytesFromOpcode(op Op) ([]byte, error) {
switch code := op.Code(); code {
case opcode.PUSHDATA1, opcode.PUSHDATA2, opcode.PUSHDATA4:
return op.Param(), nil
default:
return nil, fmt.Errorf("unexpected ByteArray opcode %s", code)
}
}
// IntFromOpcode tries to retrieve bytes from Op.
func IntFromOpcode(op Op) (int64, error) {
switch code := op.Code(); {
case code == opcode.PUSHM1:
return -1, nil
case code >= opcode.PUSH0 && code <= opcode.PUSH16:
return int64(code - opcode.PUSH0), nil
case code <= opcode.PUSHINT256:
return bigint.FromBytes(op.Param()).Int64(), nil
default:
return 0, fmt.Errorf("unexpected INT opcode %s", code)
}
}

View file

@ -0,0 +1,82 @@
package event
import (
"testing"
"github.com/nspcc-dev/neo-go/pkg/io"
"github.com/nspcc-dev/neo-go/pkg/vm"
"github.com/nspcc-dev/neo-go/pkg/vm/emit"
"github.com/stretchr/testify/require"
)
func TestBytesFromOpcode(t *testing.T) {
tests := [...][]byte{
[]byte("test"),
[]byte("test test"),
[]byte(""),
[]byte("1"),
}
bw := io.NewBufBinWriter()
for _, test := range tests {
emit.Bytes(bw.BinWriter, test)
}
var (
ctx = vm.NewContext(bw.Bytes())
op Op
gotBytes []byte
err error
)
for _, test := range tests {
op = getNextOp(ctx)
gotBytes, err = BytesFromOpcode(op)
require.NoError(t, err)
require.Equal(t, test, gotBytes)
}
}
func TestIntFromOpcode(t *testing.T) {
tests := [...]int64{
-1,
-5,
15,
16,
1_000_000,
}
bw := io.NewBufBinWriter()
for _, test := range tests {
emit.Int(bw.BinWriter, test)
}
var (
ctx = vm.NewContext(bw.Bytes())
op Op
gotInt int64
err error
)
for _, test := range tests {
op = getNextOp(ctx)
gotInt, err = IntFromOpcode(op)
require.NoError(t, err)
require.Equal(t, test, gotInt)
}
}
func getNextOp(ctx *vm.Context) (op Op) {
op.code, op.param, _ = ctx.Next()
return
}