Official Go implementation of the Ethereum protocol
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go-ethereum/accounts/abi/unpack_test.go

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// Copyright 2015 The go-ethereum Authors
// This file is part of the go-ethereum library.
//
// The go-ethereum library is free software: you can redistribute it and/or modify
// it under the terms of the GNU Lesser General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// The go-ethereum library is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU Lesser General Public License for more details.
//
// You should have received a copy of the GNU Lesser General Public License
// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
package abi
import (
"bytes"
"encoding/hex"
"fmt"
"math/big"
"reflect"
"strings"
"testing"
"github.com/ethereum/go-ethereum/common"
)
type unpackTest struct {
def string // ABI definition JSON
enc string // evm return data
want interface{} // the expected output
err string // empty or error if expected
}
func (test unpackTest) checkError(err error) error {
if err != nil {
if len(test.err) == 0 {
return fmt.Errorf("expected no err but got: %v", err)
} else if err.Error() != test.err {
return fmt.Errorf("expected err: '%v' got err: %q", test.err, err)
}
} else if len(test.err) > 0 {
return fmt.Errorf("expected err: %v but got none", test.err)
}
return nil
}
var unpackTests = []unpackTest{
{
def: `[{ "type": "bool" }]`,
enc: "0000000000000000000000000000000000000000000000000000000000000001",
want: true,
},
{
def: `[{"type": "uint32"}]`,
enc: "0000000000000000000000000000000000000000000000000000000000000001",
want: uint32(1),
},
{
def: `[{"type": "uint32"}]`,
enc: "0000000000000000000000000000000000000000000000000000000000000001",
want: uint16(0),
err: "abi: cannot unmarshal uint32 in to uint16",
},
{
def: `[{"type": "uint17"}]`,
enc: "0000000000000000000000000000000000000000000000000000000000000001",
want: uint16(0),
err: "abi: cannot unmarshal *big.Int in to uint16",
},
{
def: `[{"type": "uint17"}]`,
enc: "0000000000000000000000000000000000000000000000000000000000000001",
want: big.NewInt(1),
},
{
def: `[{"type": "int32"}]`,
enc: "0000000000000000000000000000000000000000000000000000000000000001",
want: int32(1),
},
{
def: `[{"type": "int32"}]`,
enc: "0000000000000000000000000000000000000000000000000000000000000001",
want: int16(0),
err: "abi: cannot unmarshal int32 in to int16",
},
{
def: `[{"type": "int17"}]`,
enc: "0000000000000000000000000000000000000000000000000000000000000001",
want: int16(0),
err: "abi: cannot unmarshal *big.Int in to int16",
},
{
def: `[{"type": "int17"}]`,
enc: "0000000000000000000000000000000000000000000000000000000000000001",
want: big.NewInt(1),
},
{
def: `[{"type": "address"}]`,
enc: "0000000000000000000000000100000000000000000000000000000000000000",
want: common.Address{1},
},
{
def: `[{"type": "bytes32"}]`,
enc: "0100000000000000000000000000000000000000000000000000000000000000",
want: [32]byte{1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0},
},
{
def: `[{"type": "bytes"}]`,
enc: "000000000000000000000000000000000000000000000000000000000000002000000000000000000000000000000000000000000000000000000000000000200100000000000000000000000000000000000000000000000000000000000000",
want: common.Hex2Bytes("0100000000000000000000000000000000000000000000000000000000000000"),
},
{
def: `[{"type": "bytes"}]`,
enc: "000000000000000000000000000000000000000000000000000000000000002000000000000000000000000000000000000000000000000000000000000000200100000000000000000000000000000000000000000000000000000000000000",
want: [32]byte{},
err: "abi: cannot unmarshal []uint8 in to [32]uint8",
},
{
def: `[{"type": "bytes32"}]`,
enc: "000000000000000000000000000000000000000000000000000000000000002000000000000000000000000000000000000000000000000000000000000000200100000000000000000000000000000000000000000000000000000000000000",
want: []byte(nil),
err: "abi: cannot unmarshal [32]uint8 in to []uint8",
},
{
def: `[{"type": "bytes32"}]`,
enc: "0100000000000000000000000000000000000000000000000000000000000000",
want: common.HexToHash("0100000000000000000000000000000000000000000000000000000000000000"),
},
{
def: `[{"type": "function"}]`,
enc: "0100000000000000000000000000000000000000000000000000000000000000",
want: [24]byte{1},
},
// slices
{
def: `[{"type": "uint8[]"}]`,
enc: "0000000000000000000000000000000000000000000000000000000000000020000000000000000000000000000000000000000000000000000000000000000200000000000000000000000000000000000000000000000000000000000000010000000000000000000000000000000000000000000000000000000000000002",
want: []uint8{1, 2},
},
{
def: `[{"type": "uint8[2]"}]`,
enc: "00000000000000000000000000000000000000000000000000000000000000010000000000000000000000000000000000000000000000000000000000000002",
want: [2]uint8{1, 2},
},
// multi dimensional, if these pass, all types that don't require length prefix should pass
{
def: `[{"type": "uint8[][]"}]`,
enc: "00000000000000000000000000000000000000000000000000000000000000200000000000000000000000000000000000000000000000000000000000000002000000000000000000000000000000000000000000000000000000000000008000000000000000000000000000000000000000000000000000000000000000E0000000000000000000000000000000000000000000000000000000000000000200000000000000000000000000000000000000000000000000000000000000010000000000000000000000000000000000000000000000000000000000000002000000000000000000000000000000000000000000000000000000000000000200000000000000000000000000000000000000000000000000000000000000010000000000000000000000000000000000000000000000000000000000000002",
want: [][]uint8{{1, 2}, {1, 2}},
},
{
def: `[{"type": "uint8[2][2]"}]`,
enc: "0000000000000000000000000000000000000000000000000000000000000001000000000000000000000000000000000000000000000000000000000000000200000000000000000000000000000000000000000000000000000000000000010000000000000000000000000000000000000000000000000000000000000002",
want: [2][2]uint8{{1, 2}, {1, 2}},
},
{
def: `[{"type": "uint8[][2]"}]`,
enc: "000000000000000000000000000000000000000000000000000000000000004000000000000000000000000000000000000000000000000000000000000000800000000000000000000000000000000000000000000000000000000000000001000000000000000000000000000000000000000000000000000000000000000100000000000000000000000000000000000000000000000000000000000000010000000000000000000000000000000000000000000000000000000000000001",
want: [2][]uint8{{1}, {1}},
},
{
def: `[{"type": "uint8[2][]"}]`,
enc: "0000000000000000000000000000000000000000000000000000000000000020000000000000000000000000000000000000000000000000000000000000000100000000000000000000000000000000000000000000000000000000000000010000000000000000000000000000000000000000000000000000000000000002",
want: [][2]uint8{{1, 2}},
},
{
def: `[{"type": "uint16[]"}]`,
enc: "0000000000000000000000000000000000000000000000000000000000000020000000000000000000000000000000000000000000000000000000000000000200000000000000000000000000000000000000000000000000000000000000010000000000000000000000000000000000000000000000000000000000000002",
want: []uint16{1, 2},
},
{
def: `[{"type": "uint16[2]"}]`,
enc: "00000000000000000000000000000000000000000000000000000000000000010000000000000000000000000000000000000000000000000000000000000002",
want: [2]uint16{1, 2},
},
{
def: `[{"type": "uint32[]"}]`,
enc: "0000000000000000000000000000000000000000000000000000000000000020000000000000000000000000000000000000000000000000000000000000000200000000000000000000000000000000000000000000000000000000000000010000000000000000000000000000000000000000000000000000000000000002",
want: []uint32{1, 2},
},
{
def: `[{"type": "uint32[2]"}]`,
enc: "00000000000000000000000000000000000000000000000000000000000000010000000000000000000000000000000000000000000000000000000000000002",
want: [2]uint32{1, 2},
},
{
def: `[{"type": "uint64[]"}]`,
enc: "0000000000000000000000000000000000000000000000000000000000000020000000000000000000000000000000000000000000000000000000000000000200000000000000000000000000000000000000000000000000000000000000010000000000000000000000000000000000000000000000000000000000000002",
want: []uint64{1, 2},
},
{
def: `[{"type": "uint64[2]"}]`,
enc: "00000000000000000000000000000000000000000000000000000000000000010000000000000000000000000000000000000000000000000000000000000002",
want: [2]uint64{1, 2},
},
{
def: `[{"type": "uint256[]"}]`,
enc: "0000000000000000000000000000000000000000000000000000000000000020000000000000000000000000000000000000000000000000000000000000000200000000000000000000000000000000000000000000000000000000000000010000000000000000000000000000000000000000000000000000000000000002",
want: []*big.Int{big.NewInt(1), big.NewInt(2)},
},
{
def: `[{"type": "uint256[3]"}]`,
enc: "000000000000000000000000000000000000000000000000000000000000000100000000000000000000000000000000000000000000000000000000000000020000000000000000000000000000000000000000000000000000000000000003",
want: [3]*big.Int{big.NewInt(1), big.NewInt(2), big.NewInt(3)},
},
{
def: `[{"type": "int8[]"}]`,
enc: "0000000000000000000000000000000000000000000000000000000000000020000000000000000000000000000000000000000000000000000000000000000200000000000000000000000000000000000000000000000000000000000000010000000000000000000000000000000000000000000000000000000000000002",
want: []int8{1, 2},
},
{
def: `[{"type": "int8[2]"}]`,
enc: "00000000000000000000000000000000000000000000000000000000000000010000000000000000000000000000000000000000000000000000000000000002",
want: [2]int8{1, 2},
},
{
def: `[{"type": "int16[]"}]`,
enc: "0000000000000000000000000000000000000000000000000000000000000020000000000000000000000000000000000000000000000000000000000000000200000000000000000000000000000000000000000000000000000000000000010000000000000000000000000000000000000000000000000000000000000002",
want: []int16{1, 2},
},
{
def: `[{"type": "int16[2]"}]`,
enc: "00000000000000000000000000000000000000000000000000000000000000010000000000000000000000000000000000000000000000000000000000000002",
want: [2]int16{1, 2},
},
{
def: `[{"type": "int32[]"}]`,
enc: "0000000000000000000000000000000000000000000000000000000000000020000000000000000000000000000000000000000000000000000000000000000200000000000000000000000000000000000000000000000000000000000000010000000000000000000000000000000000000000000000000000000000000002",
want: []int32{1, 2},
},
{
def: `[{"type": "int32[2]"}]`,
enc: "00000000000000000000000000000000000000000000000000000000000000010000000000000000000000000000000000000000000000000000000000000002",
want: [2]int32{1, 2},
},
{
def: `[{"type": "int64[]"}]`,
enc: "0000000000000000000000000000000000000000000000000000000000000020000000000000000000000000000000000000000000000000000000000000000200000000000000000000000000000000000000000000000000000000000000010000000000000000000000000000000000000000000000000000000000000002",
want: []int64{1, 2},
},
{
def: `[{"type": "int64[2]"}]`,
enc: "00000000000000000000000000000000000000000000000000000000000000010000000000000000000000000000000000000000000000000000000000000002",
want: [2]int64{1, 2},
},
{
def: `[{"type": "int256[]"}]`,
enc: "0000000000000000000000000000000000000000000000000000000000000020000000000000000000000000000000000000000000000000000000000000000200000000000000000000000000000000000000000000000000000000000000010000000000000000000000000000000000000000000000000000000000000002",
want: []*big.Int{big.NewInt(1), big.NewInt(2)},
},
{
def: `[{"type": "int256[3]"}]`,
enc: "000000000000000000000000000000000000000000000000000000000000000100000000000000000000000000000000000000000000000000000000000000020000000000000000000000000000000000000000000000000000000000000003",
want: [3]*big.Int{big.NewInt(1), big.NewInt(2), big.NewInt(3)},
},
}
func TestUnpack(t *testing.T) {
for i, test := range unpackTests {
def := fmt.Sprintf(`[{ "name" : "method", "outputs": %s}]`, test.def)
abi, err := JSON(strings.NewReader(def))
if err != nil {
t.Fatalf("invalid ABI definition %s: %v", def, err)
}
encb, err := hex.DecodeString(test.enc)
if err != nil {
t.Fatalf("invalid hex: %s" + test.enc)
}
outptr := reflect.New(reflect.TypeOf(test.want))
err = abi.Unpack(outptr.Interface(), "method", encb)
if err := test.checkError(err); err != nil {
t.Errorf("test %d (%v) failed: %v", i, test.def, err)
continue
}
out := outptr.Elem().Interface()
if !reflect.DeepEqual(test.want, out) {
t.Errorf("test %d (%v) failed: expected %v, got %v", i, test.def, test.want, out)
}
}
}
func TestMultiReturnWithStruct(t *testing.T) {
const definition = `[
{ "name" : "multi", "constant" : false, "outputs": [ { "name": "Int", "type": "uint256" }, { "name": "String", "type": "string" } ] }]`
abi, err := JSON(strings.NewReader(definition))
if err != nil {
t.Fatal(err)
}
// using buff to make the code readable
buff := new(bytes.Buffer)
buff.Write(common.Hex2Bytes("0000000000000000000000000000000000000000000000000000000000000001"))
buff.Write(common.Hex2Bytes("0000000000000000000000000000000000000000000000000000000000000040"))
buff.Write(common.Hex2Bytes("0000000000000000000000000000000000000000000000000000000000000005"))
stringOut := "hello"
buff.Write(common.RightPadBytes([]byte(stringOut), 32))
var inter struct {
Int *big.Int
String string
}
err = abi.Unpack(&inter, "multi", buff.Bytes())
if err != nil {
t.Error(err)
}
if inter.Int == nil || inter.Int.Cmp(big.NewInt(1)) != 0 {
t.Error("expected Int to be 1 got", inter.Int)
}
if inter.String != stringOut {
t.Error("expected String to be", stringOut, "got", inter.String)
}
var reversed struct {
String string
Int *big.Int
}
err = abi.Unpack(&reversed, "multi", buff.Bytes())
if err != nil {
t.Error(err)
}
if reversed.Int == nil || reversed.Int.Cmp(big.NewInt(1)) != 0 {
t.Error("expected Int to be 1 got", reversed.Int)
}
if reversed.String != stringOut {
t.Error("expected String to be", stringOut, "got", reversed.String)
}
}
func TestUnmarshal(t *testing.T) {
const definition = `[
{ "name" : "int", "constant" : false, "outputs": [ { "type": "uint256" } ] },
{ "name" : "bool", "constant" : false, "outputs": [ { "type": "bool" } ] },
{ "name" : "bytes", "constant" : false, "outputs": [ { "type": "bytes" } ] },
{ "name" : "fixed", "constant" : false, "outputs": [ { "type": "bytes32" } ] },
{ "name" : "multi", "constant" : false, "outputs": [ { "type": "bytes" }, { "type": "bytes" } ] },
{ "name" : "intArraySingle", "constant" : false, "outputs": [ { "type": "uint256[3]" } ] },
{ "name" : "addressSliceSingle", "constant" : false, "outputs": [ { "type": "address[]" } ] },
{ "name" : "addressSliceDouble", "constant" : false, "outputs": [ { "name": "a", "type": "address[]" }, { "name": "b", "type": "address[]" } ] },
{ "name" : "mixedBytes", "constant" : true, "outputs": [ { "name": "a", "type": "bytes" }, { "name": "b", "type": "bytes32" } ] }]`
abi, err := JSON(strings.NewReader(definition))
if err != nil {
t.Fatal(err)
}
buff := new(bytes.Buffer)
// marshall mixed bytes (mixedBytes)
p0, p0Exp := []byte{}, common.Hex2Bytes("01020000000000000000")
p1, p1Exp := [32]byte{}, common.Hex2Bytes("0000000000000000000000000000000000000000000000000000000000ddeeff")
mixedBytes := []interface{}{&p0, &p1}
buff.Write(common.Hex2Bytes("0000000000000000000000000000000000000000000000000000000000000040"))
buff.Write(common.Hex2Bytes("0000000000000000000000000000000000000000000000000000000000ddeeff"))
buff.Write(common.Hex2Bytes("000000000000000000000000000000000000000000000000000000000000000a"))
buff.Write(common.Hex2Bytes("0102000000000000000000000000000000000000000000000000000000000000"))
err = abi.Unpack(&mixedBytes, "mixedBytes", buff.Bytes())
if err != nil {
t.Error(err)
} else {
if !bytes.Equal(p0, p0Exp) {
t.Errorf("unexpected value unpacked: want %x, got %x", p0Exp, p0)
}
if !bytes.Equal(p1[:], p1Exp) {
t.Errorf("unexpected value unpacked: want %x, got %x", p1Exp, p1)
}
}
// marshal int
var Int *big.Int
err = abi.Unpack(&Int, "int", common.Hex2Bytes("0000000000000000000000000000000000000000000000000000000000000001"))
if err != nil {
t.Error(err)
}
if Int == nil || Int.Cmp(big.NewInt(1)) != 0 {
t.Error("expected Int to be 1 got", Int)
}
// marshal bool
var Bool bool
err = abi.Unpack(&Bool, "bool", common.Hex2Bytes("0000000000000000000000000000000000000000000000000000000000000001"))
if err != nil {
t.Error(err)
}
if !Bool {
t.Error("expected Bool to be true")
}
// marshal dynamic bytes max length 32
buff.Reset()
buff.Write(common.Hex2Bytes("0000000000000000000000000000000000000000000000000000000000000020"))
buff.Write(common.Hex2Bytes("0000000000000000000000000000000000000000000000000000000000000020"))
bytesOut := common.RightPadBytes([]byte("hello"), 32)
buff.Write(bytesOut)
var Bytes []byte
err = abi.Unpack(&Bytes, "bytes", buff.Bytes())
if err != nil {
t.Error(err)
}
if !bytes.Equal(Bytes, bytesOut) {
t.Errorf("expected %x got %x", bytesOut, Bytes)
}
// marshall dynamic bytes max length 64
buff.Reset()
buff.Write(common.Hex2Bytes("0000000000000000000000000000000000000000000000000000000000000020"))
buff.Write(common.Hex2Bytes("0000000000000000000000000000000000000000000000000000000000000040"))
bytesOut = common.RightPadBytes([]byte("hello"), 64)
buff.Write(bytesOut)
err = abi.Unpack(&Bytes, "bytes", buff.Bytes())
if err != nil {
t.Error(err)
}
if !bytes.Equal(Bytes, bytesOut) {
t.Errorf("expected %x got %x", bytesOut, Bytes)
}
// marshall dynamic bytes max length 64
buff.Reset()
buff.Write(common.Hex2Bytes("0000000000000000000000000000000000000000000000000000000000000020"))
buff.Write(common.Hex2Bytes("000000000000000000000000000000000000000000000000000000000000003f"))
bytesOut = common.RightPadBytes([]byte("hello"), 64)
buff.Write(bytesOut)
err = abi.Unpack(&Bytes, "bytes", buff.Bytes())
if err != nil {
t.Error(err)
}
if !bytes.Equal(Bytes, bytesOut[:len(bytesOut)-1]) {
t.Errorf("expected %x got %x", bytesOut[:len(bytesOut)-1], Bytes)
}
// marshal dynamic bytes output empty
err = abi.Unpack(&Bytes, "bytes", nil)
if err == nil {
t.Error("expected error")
}
// marshal dynamic bytes length 5
buff.Reset()
buff.Write(common.Hex2Bytes("0000000000000000000000000000000000000000000000000000000000000020"))
buff.Write(common.Hex2Bytes("0000000000000000000000000000000000000000000000000000000000000005"))
buff.Write(common.RightPadBytes([]byte("hello"), 32))
err = abi.Unpack(&Bytes, "bytes", buff.Bytes())
if err != nil {
t.Error(err)
}
if !bytes.Equal(Bytes, []byte("hello")) {
t.Errorf("expected %x got %x", bytesOut, Bytes)
}
// marshal dynamic bytes length 5
buff.Reset()
buff.Write(common.RightPadBytes([]byte("hello"), 32))
var hash common.Hash
err = abi.Unpack(&hash, "fixed", buff.Bytes())
if err != nil {
t.Error(err)
}
helloHash := common.BytesToHash(common.RightPadBytes([]byte("hello"), 32))
if hash != helloHash {
t.Errorf("Expected %x to equal %x", hash, helloHash)
}
// marshal error
buff.Reset()
buff.Write(common.Hex2Bytes("0000000000000000000000000000000000000000000000000000000000000020"))
err = abi.Unpack(&Bytes, "bytes", buff.Bytes())
if err == nil {
t.Error("expected error")
}
err = abi.Unpack(&Bytes, "multi", make([]byte, 64))
if err == nil {
t.Error("expected error")
}
buff.Reset()
buff.Write(common.Hex2Bytes("0000000000000000000000000000000000000000000000000000000000000001"))
buff.Write(common.Hex2Bytes("0000000000000000000000000000000000000000000000000000000000000002"))
buff.Write(common.Hex2Bytes("0000000000000000000000000000000000000000000000000000000000000003"))
// marshal int array
var intArray [3]*big.Int
err = abi.Unpack(&intArray, "intArraySingle", buff.Bytes())
if err != nil {
t.Error(err)
}
var testAgainstIntArray [3]*big.Int
testAgainstIntArray[0] = big.NewInt(1)
testAgainstIntArray[1] = big.NewInt(2)
testAgainstIntArray[2] = big.NewInt(3)
for i, Int := range intArray {
if Int.Cmp(testAgainstIntArray[i]) != 0 {
t.Errorf("expected %v, got %v", testAgainstIntArray[i], Int)
}
}
// marshal address slice
buff.Reset()
buff.Write(common.Hex2Bytes("0000000000000000000000000000000000000000000000000000000000000020")) // offset
buff.Write(common.Hex2Bytes("0000000000000000000000000000000000000000000000000000000000000001")) // size
buff.Write(common.Hex2Bytes("0000000000000000000000000100000000000000000000000000000000000000"))
var outAddr []common.Address
err = abi.Unpack(&outAddr, "addressSliceSingle", buff.Bytes())
if err != nil {
t.Fatal("didn't expect error:", err)
}
if len(outAddr) != 1 {
t.Fatal("expected 1 item, got", len(outAddr))
}
if outAddr[0] != (common.Address{1}) {
t.Errorf("expected %x, got %x", common.Address{1}, outAddr[0])
}
// marshal multiple address slice
buff.Reset()
buff.Write(common.Hex2Bytes("0000000000000000000000000000000000000000000000000000000000000040")) // offset
buff.Write(common.Hex2Bytes("0000000000000000000000000000000000000000000000000000000000000080")) // offset
buff.Write(common.Hex2Bytes("0000000000000000000000000000000000000000000000000000000000000001")) // size
buff.Write(common.Hex2Bytes("0000000000000000000000000100000000000000000000000000000000000000"))
buff.Write(common.Hex2Bytes("0000000000000000000000000000000000000000000000000000000000000002")) // size
buff.Write(common.Hex2Bytes("0000000000000000000000000200000000000000000000000000000000000000"))
buff.Write(common.Hex2Bytes("0000000000000000000000000300000000000000000000000000000000000000"))
var outAddrStruct struct {
A []common.Address
B []common.Address
}
err = abi.Unpack(&outAddrStruct, "addressSliceDouble", buff.Bytes())
if err != nil {
t.Fatal("didn't expect error:", err)
}
if len(outAddrStruct.A) != 1 {
t.Fatal("expected 1 item, got", len(outAddrStruct.A))
}
if outAddrStruct.A[0] != (common.Address{1}) {
t.Errorf("expected %x, got %x", common.Address{1}, outAddrStruct.A[0])
}
if len(outAddrStruct.B) != 2 {
t.Fatal("expected 1 item, got", len(outAddrStruct.B))
}
if outAddrStruct.B[0] != (common.Address{2}) {
t.Errorf("expected %x, got %x", common.Address{2}, outAddrStruct.B[0])
}
if outAddrStruct.B[1] != (common.Address{3}) {
t.Errorf("expected %x, got %x", common.Address{3}, outAddrStruct.B[1])
}
// marshal invalid address slice
buff.Reset()
buff.Write(common.Hex2Bytes("0000000000000000000000000000000000000000000000000000000000000100"))
err = abi.Unpack(&outAddr, "addressSliceSingle", buff.Bytes())
if err == nil {
t.Fatal("expected error:", err)
}
}