diff --git a/accounts/abi/unpack_test.go b/accounts/abi/unpack_test.go
index 02d4a4797f..b8236edf39 100644
--- a/accounts/abi/unpack_test.go
+++ b/accounts/abi/unpack_test.go
@@ -18,6 +18,7 @@ package abi
 
 import (
 	"bytes"
+	"encoding/hex"
 	"fmt"
 	"math/big"
 	"reflect"
@@ -27,531 +28,258 @@ import (
 	"github.com/ethereum/go-ethereum/common"
 )
 
-func TestSingleValueUnpack(t *testing.T) {
-	for i, test := range []struct {
-		def              string      // definition of the **output** ABI params
-		marshalledOutput []byte      // evm return data
-		expectedOut      interface{} // the expected output
-		outVar           string      // the output variable (e.g. uint32, *big.Int, etc)
-		err              string      // empty or error if expected
-	}{
-		{
-			`[ { "type": "bool" } ]`,
-			common.Hex2Bytes("0000000000000000000000000000000000000000000000000000000000000001"),
-			bool(true),
-			"bool",
-			"",
-		},
-		{
-			`[ { "type": "uint32" } ]`,
-			common.Hex2Bytes("0000000000000000000000000000000000000000000000000000000000000001"),
-			uint32(1),
-			"uint32",
-			"",
-		},
-		{
-			`[ { "type": "uint32" } ]`,
-			common.Hex2Bytes("0000000000000000000000000000000000000000000000000000000000000001"),
-			nil,
-			"uint16",
-			"abi: cannot unmarshal uint32 in to uint16",
-		},
-		{
-			`[ { "type": "uint17" } ]`,
-			common.Hex2Bytes("0000000000000000000000000000000000000000000000000000000000000001"),
-			nil,
-			"uint16",
-			"abi: cannot unmarshal *big.Int in to uint16",
-		},
-		{
-			`[ { "type": "uint17" } ]`,
-			common.Hex2Bytes("0000000000000000000000000000000000000000000000000000000000000001"),
-			big.NewInt(1),
-			"*big.Int",
-			"",
-		},
-
-		{
-			`[ { "type": "int32" } ]`,
-			common.Hex2Bytes("0000000000000000000000000000000000000000000000000000000000000001"),
-			int32(1),
-			"int32",
-			"",
-		},
-		{
-			`[ { "type": "int32" } ]`,
-			common.Hex2Bytes("0000000000000000000000000000000000000000000000000000000000000001"),
-			nil,
-			"int16",
-			"abi: cannot unmarshal int32 in to int16",
-		},
-		{
-			`[ { "type": "int17" } ]`,
-			common.Hex2Bytes("0000000000000000000000000000000000000000000000000000000000000001"),
-			nil,
-			"int16",
-			"abi: cannot unmarshal *big.Int in to int16",
-		},
-		{
-			`[ { "type": "int17" } ]`,
-			common.Hex2Bytes("0000000000000000000000000000000000000000000000000000000000000001"),
-			big.NewInt(1),
-			"*big.Int",
-			"",
-		},
-
-		{
-			`[ { "type": "address" } ]`,
-			common.Hex2Bytes("0000000000000000000000000100000000000000000000000000000000000000"),
-			common.Address{1},
-			"address",
-			"",
-		},
-		{
-			`[ { "type": "bytes32" } ]`,
-			common.Hex2Bytes("0100000000000000000000000000000000000000000000000000000000000000"),
-			[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},
-			"fixedBytes32",
-			"",
-		},
-		{
-			`[ { "type": "bytes" } ]`,
-			common.Hex2Bytes("000000000000000000000000000000000000000000000000000000000000002000000000000000000000000000000000000000000000000000000000000000200100000000000000000000000000000000000000000000000000000000000000"),
-			common.Hex2Bytes("0100000000000000000000000000000000000000000000000000000000000000"),
-			"bytes",
-			"",
-		},
-		{
-			`[ { "type": "bytes" } ]`,
-			common.Hex2Bytes("000000000000000000000000000000000000000000000000000000000000002000000000000000000000000000000000000000000000000000000000000000200100000000000000000000000000000000000000000000000000000000000000"),
-			nil,
-			"fixedBytes32",
-			"abi: cannot unmarshal []uint8 in to [32]uint8",
-		},
-		{
-			`[ { "type": "bytes32" } ]`,
-			common.Hex2Bytes("000000000000000000000000000000000000000000000000000000000000002000000000000000000000000000000000000000000000000000000000000000200100000000000000000000000000000000000000000000000000000000000000"),
-			nil,
-			"bytes",
-			"abi: cannot unmarshal [32]uint8 in to []uint8",
-		},
-		{
-			`[ { "type": "bytes32" } ]`,
-			common.Hex2Bytes("0100000000000000000000000000000000000000000000000000000000000000"),
-			common.Hex2Bytes("0100000000000000000000000000000000000000000000000000000000000000"),
-			"hash",
-			"",
-		},
-		{
-			`[ { "type": "function" } ]`,
-			common.Hex2Bytes("0100000000000000000000000000000000000000000000000000000000000000"),
-			[24]byte{1},
-			"function",
-			"",
-		},
-	} {
-		abiDefinition := fmt.Sprintf(`[{ "name" : "method", "outputs": %s}]`, test.def)
-		abi, err := JSON(strings.NewReader(abiDefinition))
-		if err != nil {
-			t.Errorf("%d failed. %v", i, err)
-			continue
-		}
-
-		var outvar interface{}
-		switch test.outVar {
-		case "bool":
-			var v bool
-			err = abi.Unpack(&v, "method", test.marshalledOutput)
-			outvar = v
-		case "uint8":
-			var v uint8
-			err = abi.Unpack(&v, "method", test.marshalledOutput)
-			outvar = v
-		case "uint16":
-			var v uint16
-			err = abi.Unpack(&v, "method", test.marshalledOutput)
-			outvar = v
-		case "uint32":
-			var v uint32
-			err = abi.Unpack(&v, "method", test.marshalledOutput)
-			outvar = v
-		case "uint64":
-			var v uint64
-			err = abi.Unpack(&v, "method", test.marshalledOutput)
-			outvar = v
-		case "int8":
-			var v int8
-			err = abi.Unpack(&v, "method", test.marshalledOutput)
-			outvar = v
-		case "int16":
-			var v int16
-			err = abi.Unpack(&v, "method", test.marshalledOutput)
-			outvar = v
-		case "int32":
-			var v int32
-			err = abi.Unpack(&v, "method", test.marshalledOutput)
-			outvar = v
-		case "int64":
-			var v int64
-			err = abi.Unpack(&v, "method", test.marshalledOutput)
-			outvar = v
-		case "*big.Int":
-			var v *big.Int
-			err = abi.Unpack(&v, "method", test.marshalledOutput)
-			outvar = v
-		case "address":
-			var v common.Address
-			err = abi.Unpack(&v, "method", test.marshalledOutput)
-			outvar = v
-		case "bytes":
-			var v []byte
-			err = abi.Unpack(&v, "method", test.marshalledOutput)
-			outvar = v
-		case "fixedBytes32":
-			// this is a bit presumptive but will work for testing for now
-			var v [32]byte
-			err = abi.Unpack(&v, "method", test.marshalledOutput)
-			outvar = v
-		case "hash":
-			var v common.Hash
-			err = abi.Unpack(&v, "method", test.marshalledOutput)
-			outvar = v.Bytes()[:]
-		case "function":
-			var v [24]byte
-			err = abi.Unpack(&v, "method", test.marshalledOutput)
-			outvar = v
-		default:
-			t.Errorf("unsupported type '%v' please add it to the switch statement in this test", test.outVar)
-			continue
-		}
-
-		if err != nil && len(test.err) == 0 {
-			t.Errorf("%d failed. Expected no err but got: %v", i, err)
-			continue
-		}
-		if err == nil && len(test.err) != 0 {
-			t.Errorf("%d failed. Expected err: %v but got none", i, test.err)
-			continue
-		}
-		if err != nil && len(test.err) != 0 && err.Error() != test.err {
-			t.Errorf("%d failed. Expected err: '%v' got err: '%v'", i, test.err, err)
-			continue
-		}
-
-		if err == nil {
-			if !reflect.DeepEqual(test.expectedOut, outvar) {
-				t.Errorf("%d failed. Output error: expected %v, got %v", i, test.expectedOut, outvar)
-			}
-		}
-	}
+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 TestSingleArraysAndSlicesUnpack(t *testing.T) {
-	for i, test := range []struct {
-		def              string      // definition of the **output** ABI params
-		marshalledOutput []byte      // evm return data
-		expectedOut      interface{} // the expected output
-		outVar           string      // the output variable (e.g. uint32, *big.Int, etc)
-		err              string      // empty or error if expected
-	}{
-		{
-			`[ { "type": "uint8[]" } ]`,
-			common.Hex2Bytes("0000000000000000000000000000000000000000000000000000000000000020000000000000000000000000000000000000000000000000000000000000000200000000000000000000000000000000000000000000000000000000000000010000000000000000000000000000000000000000000000000000000000000002"),
-			[]uint8{1, 2},
-			"[]uint8",
-			"",
-		},
-		{
-			`[ { "type": "uint8[2]" } ]`,
-			common.Hex2Bytes("00000000000000000000000000000000000000000000000000000000000000010000000000000000000000000000000000000000000000000000000000000002"),
-			[2]uint8{1, 2},
-			"[2]uint8",
-			"",
-		},
-		// multi dimensional, if these pass, all types that don't require length prefix should pass
-		{
-			`[ { "type": "uint8[][]" } ]`,
-			common.Hex2Bytes("00000000000000000000000000000000000000000000000000000000000000200000000000000000000000000000000000000000000000000000000000000002000000000000000000000000000000000000000000000000000000000000008000000000000000000000000000000000000000000000000000000000000000E0000000000000000000000000000000000000000000000000000000000000000200000000000000000000000000000000000000000000000000000000000000010000000000000000000000000000000000000000000000000000000000000002000000000000000000000000000000000000000000000000000000000000000200000000000000000000000000000000000000000000000000000000000000010000000000000000000000000000000000000000000000000000000000000002"),
-			[][]uint8{{1, 2}, {1, 2}},
-			"[][]uint8",
-			"",
-		},
-		{
-			`[ { "type": "uint8[2][2]" } ]`,
-			common.Hex2Bytes("0000000000000000000000000000000000000000000000000000000000000001000000000000000000000000000000000000000000000000000000000000000200000000000000000000000000000000000000000000000000000000000000010000000000000000000000000000000000000000000000000000000000000002"),
-			[2][2]uint8{{1, 2}, {1, 2}},
-			"[2][2]uint8",
-			"",
-		},
-		{
-			`[ { "type": "uint8[][2]" } ]`,
-			common.Hex2Bytes("000000000000000000000000000000000000000000000000000000000000004000000000000000000000000000000000000000000000000000000000000000800000000000000000000000000000000000000000000000000000000000000001000000000000000000000000000000000000000000000000000000000000000100000000000000000000000000000000000000000000000000000000000000010000000000000000000000000000000000000000000000000000000000000001"),
-			[2][]uint8{{1}, {1}},
-			"[2][]uint8",
-			"",
-		},
-		{
-			`[ { "type": "uint8[2][]" } ]`,
-			common.Hex2Bytes("0000000000000000000000000000000000000000000000000000000000000020000000000000000000000000000000000000000000000000000000000000000100000000000000000000000000000000000000000000000000000000000000010000000000000000000000000000000000000000000000000000000000000002"),
-			[][2]uint8{{1, 2}},
-			"[][2]uint8",
-			"",
-		},
-		{
-			`[ { "type": "uint16[]" } ]`,
-			common.Hex2Bytes("0000000000000000000000000000000000000000000000000000000000000020000000000000000000000000000000000000000000000000000000000000000200000000000000000000000000000000000000000000000000000000000000010000000000000000000000000000000000000000000000000000000000000002"),
-			[]uint16{1, 2},
-			"[]uint16",
-			"",
-		},
-		{
-			`[ { "type": "uint16[2]" } ]`,
-			common.Hex2Bytes("00000000000000000000000000000000000000000000000000000000000000010000000000000000000000000000000000000000000000000000000000000002"),
-			[2]uint16{1, 2},
-			"[2]uint16",
-			"",
-		},
-		{
-			`[ { "type": "uint32[]" } ]`,
-			common.Hex2Bytes("0000000000000000000000000000000000000000000000000000000000000020000000000000000000000000000000000000000000000000000000000000000200000000000000000000000000000000000000000000000000000000000000010000000000000000000000000000000000000000000000000000000000000002"),
-			[]uint32{1, 2},
-			"[]uint32",
-			"",
-		},
-		{
-			`[ { "type": "uint32[2]" } ]`,
-			common.Hex2Bytes("00000000000000000000000000000000000000000000000000000000000000010000000000000000000000000000000000000000000000000000000000000002"),
-			[2]uint32{1, 2},
-			"[2]uint32",
-			"",
-		},
-		{
-			`[ { "type": "uint64[]" } ]`,
-			common.Hex2Bytes("0000000000000000000000000000000000000000000000000000000000000020000000000000000000000000000000000000000000000000000000000000000200000000000000000000000000000000000000000000000000000000000000010000000000000000000000000000000000000000000000000000000000000002"),
-			[]uint64{1, 2},
-			"[]uint64",
-			"",
-		},
-		{
-			`[ { "type": "uint64[2]" } ]`,
-			common.Hex2Bytes("00000000000000000000000000000000000000000000000000000000000000010000000000000000000000000000000000000000000000000000000000000002"),
-			[2]uint64{1, 2},
-			"[2]uint64",
-			"",
-		},
-		{
-			`[ { "type": "uint256[]" } ]`,
-			common.Hex2Bytes("0000000000000000000000000000000000000000000000000000000000000020000000000000000000000000000000000000000000000000000000000000000200000000000000000000000000000000000000000000000000000000000000010000000000000000000000000000000000000000000000000000000000000002"),
-			[]*big.Int{big.NewInt(1), big.NewInt(2)},
-			"[]*big.Int",
-			"",
-		},
-		{
-			`[ { "type": "uint256[3]" } ]`,
-			append(pad([]byte{1}, 32, true), append(pad([]byte{2}, 32, true), pad([]byte{3}, 32, true)...)...),
-			[3]*big.Int{big.NewInt(1), big.NewInt(2), big.NewInt(3)},
-			"[3]*big.Int",
-			"",
-		},
-		{
-			`[ { "type": "int8[]" } ]`,
-			common.Hex2Bytes("0000000000000000000000000000000000000000000000000000000000000020000000000000000000000000000000000000000000000000000000000000000200000000000000000000000000000000000000000000000000000000000000010000000000000000000000000000000000000000000000000000000000000002"),
-			[]int8{1, 2},
-			"[]int8",
-			"",
-		},
-		{
-			`[ { "type": "int8[2]" } ]`,
-			common.Hex2Bytes("00000000000000000000000000000000000000000000000000000000000000010000000000000000000000000000000000000000000000000000000000000002"),
-			[2]int8{1, 2},
-			"[2]int8",
-			"",
-		},
-		{
-			`[ { "type": "int16[]" } ]`,
-			common.Hex2Bytes("0000000000000000000000000000000000000000000000000000000000000020000000000000000000000000000000000000000000000000000000000000000200000000000000000000000000000000000000000000000000000000000000010000000000000000000000000000000000000000000000000000000000000002"),
-			[]int16{1, 2},
-			"[]int16",
-			"",
-		},
-		{
-			`[ { "type": "int16[2]" } ]`,
-			common.Hex2Bytes("00000000000000000000000000000000000000000000000000000000000000010000000000000000000000000000000000000000000000000000000000000002"),
-			[2]int16{1, 2},
-			"[2]int16",
-			"",
-		},
-		{
-			`[ { "type": "int32[]" } ]`,
-			common.Hex2Bytes("0000000000000000000000000000000000000000000000000000000000000020000000000000000000000000000000000000000000000000000000000000000200000000000000000000000000000000000000000000000000000000000000010000000000000000000000000000000000000000000000000000000000000002"),
-			[]int32{1, 2},
-			"[]int32",
-			"",
-		},
-		{
-			`[ { "type": "int32[2]" } ]`,
-			common.Hex2Bytes("00000000000000000000000000000000000000000000000000000000000000010000000000000000000000000000000000000000000000000000000000000002"),
-			[2]int32{1, 2},
-			"[2]int32",
-			"",
-		},
-		{
-			`[ { "type": "int64[]" } ]`,
-			common.Hex2Bytes("0000000000000000000000000000000000000000000000000000000000000020000000000000000000000000000000000000000000000000000000000000000200000000000000000000000000000000000000000000000000000000000000010000000000000000000000000000000000000000000000000000000000000002"),
-			[]int64{1, 2},
-			"[]int64",
-			"",
-		},
-		{
-			`[ { "type": "int64[2]" } ]`,
-			common.Hex2Bytes("00000000000000000000000000000000000000000000000000000000000000010000000000000000000000000000000000000000000000000000000000000002"),
-			[2]int64{1, 2},
-			"[2]int64",
-			"",
-		},
-		{
-			`[ { "type": "int256[]" } ]`,
-			common.Hex2Bytes("0000000000000000000000000000000000000000000000000000000000000020000000000000000000000000000000000000000000000000000000000000000200000000000000000000000000000000000000000000000000000000000000010000000000000000000000000000000000000000000000000000000000000002"),
-			[]*big.Int{big.NewInt(1), big.NewInt(2)},
-			"[]*big.Int",
-			"",
-		},
-		{
-			`[ { "type": "int256[3]" } ]`,
-			common.Hex2Bytes("000000000000000000000000000000000000000000000000000000000000000100000000000000000000000000000000000000000000000000000000000000020000000000000000000000000000000000000000000000000000000000000003"),
-			[3]*big.Int{big.NewInt(1), big.NewInt(2), big.NewInt(3)},
-			"[3]*big.Int",
-			"",
-		},
-	} {
-		abiDefinition := fmt.Sprintf(`[{ "name" : "method", "outputs": %s}]`, test.def)
-		abi, err := JSON(strings.NewReader(abiDefinition))
+
+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.Errorf("%d failed. %v", i, err)
+			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
 		}
-
-		var outvar interface{}
-		switch test.outVar {
-		case "[][]uint8":
-			var v [][]uint8
-			err = abi.Unpack(&v, "method", test.marshalledOutput)
-			outvar = v
-		case "[2][2]uint8":
-			var v [2][2]uint8
-			err = abi.Unpack(&v, "method", test.marshalledOutput)
-			outvar = v
-		case "[][2]uint8":
-			var v [][2]uint8
-			err = abi.Unpack(&v, "method", test.marshalledOutput)
-			outvar = v
-		case "[2][]uint8":
-			var v [2][]uint8
-			err = abi.Unpack(&v, "method", test.marshalledOutput)
-			outvar = v
-		case "[2][2][2]uint8":
-			var v [2][2][2]uint8
-			err = abi.Unpack(&v, "method", test.marshalledOutput)
-			outvar = v
-		case "[][][]uint8":
-			var v [][][]uint8
-			err = abi.Unpack(&v, "method", test.marshalledOutput)
-			outvar = v
-		case "[]uint8":
-			var v []uint8
-			err = abi.Unpack(&v, "method", test.marshalledOutput)
-			outvar = v
-		case "[2]uint8":
-			var v [2]uint8
-			err = abi.Unpack(&v, "method", test.marshalledOutput)
-			outvar = v
-		case "[]uint16":
-			var v []uint16
-			err = abi.Unpack(&v, "method", test.marshalledOutput)
-			outvar = v
-		case "[2]uint16":
-			var v [2]uint16
-			err = abi.Unpack(&v, "method", test.marshalledOutput)
-			outvar = v
-		case "[]uint32":
-			var v []uint32
-			err = abi.Unpack(&v, "method", test.marshalledOutput)
-			outvar = v
-		case "[2]uint32":
-			var v [2]uint32
-			err = abi.Unpack(&v, "method", test.marshalledOutput)
-			outvar = v
-		case "[]uint64":
-			var v []uint64
-			err = abi.Unpack(&v, "method", test.marshalledOutput)
-			outvar = v
-		case "[2]uint64":
-			var v [2]uint64
-			err = abi.Unpack(&v, "method", test.marshalledOutput)
-			outvar = v
-		case "[]int8":
-			var v []int8
-			err = abi.Unpack(&v, "method", test.marshalledOutput)
-			outvar = v
-		case "[2]int8":
-			var v [2]int8
-			err = abi.Unpack(&v, "method", test.marshalledOutput)
-			outvar = v
-		case "[]int16":
-			var v []int16
-			err = abi.Unpack(&v, "method", test.marshalledOutput)
-			outvar = v
-		case "[2]int16":
-			var v [2]int16
-			err = abi.Unpack(&v, "method", test.marshalledOutput)
-			outvar = v
-		case "[]int32":
-			var v []int32
-			err = abi.Unpack(&v, "method", test.marshalledOutput)
-			outvar = v
-		case "[2]int32":
-			var v [2]int32
-			err = abi.Unpack(&v, "method", test.marshalledOutput)
-			outvar = v
-		case "[]int64":
-			var v []int64
-			err = abi.Unpack(&v, "method", test.marshalledOutput)
-			outvar = v
-		case "[2]int64":
-			var v [2]int64
-			err = abi.Unpack(&v, "method", test.marshalledOutput)
-			outvar = v
-		case "[3]*big.Int":
-			var v [3]*big.Int
-			err = abi.Unpack(&v, "method", test.marshalledOutput)
-			outvar = v
-		case "[]*big.Int":
-			var v []*big.Int
-			err = abi.Unpack(&v, "method", test.marshalledOutput)
-			outvar = v
-		default:
-			t.Errorf("unsupported type '%v' please add it to the switch statement in this test", test.outVar)
-			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)
 		}
-
-		if err != nil && len(test.err) == 0 {
-			t.Errorf("%d failed. Expected no err but got: %v", i, err)
-			continue
-		}
-		if err == nil && len(test.err) != 0 {
-			t.Errorf("%d failed. Expected err: %v but got none", i, test.err)
-			continue
-		}
-		if err != nil && len(test.err) != 0 && err.Error() != test.err {
-			t.Errorf("%d failed. Expected err: '%v' got err: '%v'", i, test.err, err)
-			continue
-		}
-
-		if err == nil {
-			if !reflect.DeepEqual(test.expectedOut, outvar) {
-				t.Errorf("%d failed. Output error: expected %v, got %v", i, test.expectedOut, outvar)
-			}
-		}
-
 	}
 }