feat(pkg/scale): add use of pkg/error Wrap for error handling (#2708)

dot/rpc/modules/author_test.go

@@ -86,7 +86,7 @@ func TestAuthorModule_HasSessionKeys(t *testing.T) {
 				req: &HasSessionKeyRequest{"0x01"},
 			},
 			exp:    false,
-			expErr: errors.New("unsupported Option value: 4, bytes: [1]"),
+			expErr: errors.New("unsupported option: value: 4, bytes: [1]"),
 		},
 		{
 			name: "happy path",

lib/babe/verify_test.go

@@ -163,9 +163,10 @@ func Test_getAuthorityIndex(t *testing.T) {
 			expErr: errors.New("first digest item is not pre-runtime digest"),
 		},
 		{
-			name:   "Invalid Preruntime Digest Type",
-			args:   args{headerInvalidPre},
-			expErr: errors.New("cannot decode babe header from pre-digest: EOF, field: 0"),
+			name: "Invalid Preruntime Digest Type",
+			args: args{headerInvalidPre},
+			expErr: errors.New("cannot decode babe header from pre-digest: decoding struct: unmarshalling field at" +
+				" index 0: EOF"),
 		},
 		{
 			name: "BabePrimaryPreDigest Type",
@@ -382,7 +383,8 @@ func Test_verifier_verifyPreRuntimeDigest(t *testing.T) {
 			name:     "Invalid PreRuntimeDigest",
 			verifier: verifier{},
 			args:     args{&types.PreRuntimeDigest{Data: []byte{0}}},
-			expErr:   errors.New("unable to find VaryingDataTypeValue with index: 0"),
+			expErr: errors.New(
+				"unable to find VaryingDataTypeValue with index: for key 0"),
 		},
 		{
 			name:     "Invalid BlockProducer Index",
@@ -615,7 +617,8 @@ func Test_verifier_verifyAuthorshipRight(t *testing.T) {
 			name:     "invalid preruntime digest data",
 			verifier: verifier{},
 			header:   header2,
-			expErr:   errors.New("failed to verify pre-runtime digest: EOF, field: 0"),
+			expErr: errors.New("failed to verify pre-runtime digest: decoding struct: unmarshalling field at index" +
+				" 0: EOF"),
 		},
 		{
 			name:     "invalid seal length",

lib/grandpa/message_handler_test.go

@@ -1286,8 +1286,8 @@ func TestService_VerifyBlockJustification(t *testing.T) {
 				justification: []byte{1, 2, 3},
 			},
 			want: nil,
-			wantErr: errors.New("EOF, field: 0x0000000000000000000000000000000000000000000000000000000000000000, " +
-				"field: {Hash:0x0000000000000000000000000000000000000000000000000000000000000000 Number:0 Precommits:[]}"),
+			wantErr: errors.New("decoding struct: unmarshalling field at index 1: decoding struct: unmarshalling" +
+				" field at index 0: EOF"),
 		},
 		"valid justification": {
 			fields: fields{

lib/runtime/version.go

@@ -7,6 +7,7 @@ import (
 	"bytes"
 	"errors"
 	"fmt"
+	"io"
 
 	"github.com/ChainSafe/gossamer/pkg/scale"
 )
@@ -69,7 +70,7 @@ func DecodeVersion(encoded []byte) (version Version, err error) {
 	for _, optionalField := range optionalFields {
 		err = decoder.Decode(optionalField.value)
 		if err != nil {
-			if err.Error() == "EOF" {
+			if errors.Is(err, io.EOF) {
 				return version, nil
 			}
 			return Version{}, fmt.Errorf("%w %s: %s", ErrDecodingVersionField, optionalField.name, err)

pkg/scale/decode.go

@@ -60,24 +60,15 @@ func indirect(dstv reflect.Value) (elem reflect.Value) {
 func Unmarshal(data []byte, dst interface{}) (err error) {
 	dstv := reflect.ValueOf(dst)
 	if dstv.Kind() != reflect.Ptr || dstv.IsNil() {
-		err = fmt.Errorf("unsupported dst: %T, must be a pointer to a destination", dst)
+		err = fmt.Errorf("%w: %T", ErrUnsupportedDestination, dst)
 		return
 	}
 
-	elem := indirect(dstv)
-	if err != nil {
-		return
-	}
-
-	buf := &bytes.Buffer{}
 	ds := decodeState{}
-	_, err = buf.Write(data)
-	if err != nil {
-		return
-	}
-	ds.Reader = buf
 
-	err = ds.unmarshal(elem)
+	ds.Reader = bytes.NewBuffer(data)
+
+	err = ds.unmarshal(indirect(dstv))
 	if err != nil {
 		return
 	}
@@ -93,15 +84,15 @@ type Decoder struct {
 func (d *Decoder) Decode(dst interface{}) (err error) {
 	dstv := reflect.ValueOf(dst)
 	if dstv.Kind() != reflect.Ptr || dstv.IsNil() {
-		err = fmt.Errorf("unsupported dst: %T, must be a pointer to a destination", dst)
+		err = fmt.Errorf("%w: %T", ErrUnsupportedDestination, dst)
 		return
 	}
 
-	elem := indirect(dstv)
+	err = d.unmarshal(indirect(dstv))
 	if err != nil {
 		return
 	}
-	return d.unmarshal(elem)
+	return nil
 }
 
 // NewDecoder is constructor for Decoder
@@ -160,7 +151,7 @@ func (ds *decodeState) unmarshal(dstv reflect.Value) (err error) {
 		case reflect.Slice:
 			err = ds.decodeSlice(dstv)
 		default:
-			err = fmt.Errorf("unsupported type: %T", in)
+			err = fmt.Errorf("%w: %T", ErrUnsupportedType, in)
 		}
 	}
 	return
@@ -244,7 +235,7 @@ func (ds *decodeState) decodeCustomPrimitive(dstv reflect.Value) (err error) {
 			break
 		}
 	default:
-		err = fmt.Errorf("unsupported type for custom primitive: %T", in)
+		err = fmt.Errorf("%w: %T", ErrUnsupportedType, in)
 		return
 	}
 	dstv.Set(temp.Elem().Convert(inType))
@@ -291,7 +282,7 @@ func (ds *decodeState) decodeResult(dstv reflect.Value) (err error) {
 		dstv.Set(reflect.ValueOf(res))
 	default:
 		bytes, _ := io.ReadAll(ds.Reader)
-		err = fmt.Errorf("unsupported Result value: %v, bytes: %v", rb, bytes)
+		err = fmt.Errorf("%w: value: %v, bytes: %v", ErrUnsupportedResult, rb, bytes)
 	}
 	return
 }
@@ -324,7 +315,7 @@ func (ds *decodeState) decodePointer(dstv reflect.Value) (err error) {
 		}
 	default:
 		bytes, _ := io.ReadAll(ds.Reader)
-		err = fmt.Errorf("unsupported Option value: %v, bytes: %v", rb, bytes)
+		err = fmt.Errorf("%w: value: %v, bytes: %v", errUnsupportedOption, rb, bytes)
 	}
 	return
 }
@@ -372,7 +363,7 @@ func (ds *decodeState) decodeVaryingDataType(dstv reflect.Value) (err error) {
 	vdt := dstv.Interface().(VaryingDataType)
 	val, ok := vdt.cache[uint(b)]
 	if !ok {
-		err = fmt.Errorf("unable to find VaryingDataTypeValue with index: %d", uint(b))
+		err = fmt.Errorf("%w: for key %d", errUnknownVaryingDataTypeValue, uint(b))
 		return
 	}
 
@@ -448,8 +439,7 @@ func (ds *decodeState) decodeStruct(dstv reflect.Value) (err error) {
 		}
 		err = ds.unmarshal(field)
 		if err != nil {
-			err = fmt.Errorf("%s, field: %+v", err, field)
-			return
+			return fmt.Errorf("decoding struct: unmarshalling field at index %d: %w", i.fieldIndex, err)
 		}
 	}
 	dstv.Set(temp.Elem())
@@ -470,7 +460,7 @@ func (ds *decodeState) decodeBool(dstv reflect.Value) (err error) {
 	case 0x01:
 		b = true
 	default:
-		err = fmt.Errorf("could not decode invalid bool")
+		err = fmt.Errorf("%w", errDecodeBool)
 	}
 	dstv.Set(reflect.ValueOf(b))
 	return
@@ -538,7 +528,6 @@ func (ds *decodeState) decodeUint(dstv reflect.Value) (err error) {
 			}
 		default:
 			return fmt.Errorf("%w: %d", ErrCompactUintPrefixUnknown, prefix)
-
 		}
 	}
 	temp.Elem().Set(reflect.ValueOf(value).Convert(reflect.TypeOf(in)))
@@ -636,7 +625,7 @@ func (ds *decodeState) decodeBigInt(dstv reflect.Value) (err error) {
 		buf := make([]byte, byteLen)
 		_, err = ds.Read(buf)
 		if err != nil {
-			err = fmt.Errorf("could not decode invalid big.Int: %v", err)
+			err = fmt.Errorf("reading bytes: %w", err)
 			break
 		}
 		o := reverseBytes(buf)

pkg/scale/encode.go

@@ -107,7 +107,7 @@ func (es *encodeState) marshal(in interface{}) (err error) {
 		case reflect.Slice:
 			err = es.encodeSlice(in)
 		default:
-			err = fmt.Errorf("unsupported type: %T", in)
+			err = fmt.Errorf("%w: %T", ErrUnsupportedType, in)
 		}
 	}
 	return
@@ -140,7 +140,7 @@ func (es *encodeState) encodeCustomPrimitive(in interface{}) (err error) {
 	case reflect.Uint64:
 		in = reflect.ValueOf(in).Convert(reflect.TypeOf(uint64(0))).Interface()
 	default:
-		err = fmt.Errorf("unsupported type for custom primitive: %T", in)
+		err = fmt.Errorf("%w: %T", ErrUnsupportedCustomPrimitive, in)
 		return
 	}
 	err = es.marshal(in)
@@ -149,7 +149,7 @@ func (es *encodeState) encodeCustomPrimitive(in interface{}) (err error) {
 
 func (es *encodeState) encodeResult(res Result) (err error) {
 	if !res.IsSet() {
-		err = fmt.Errorf("Result is not set: %+v", res)
+		err = fmt.Errorf("%w: %+v", ErrResultNotSet, res)
 		return
 	}
 
@@ -230,7 +230,7 @@ func (es *encodeState) encodeArray(in interface{}) (err error) {
 func (es *encodeState) encodeBigInt(i *big.Int) (err error) {
 	switch {
 	case i == nil:
-		err = fmt.Errorf("nil *big.Int")
+		err = fmt.Errorf("%w", errBigIntIsNil)
 	case i.Cmp(new(big.Int).Lsh(big.NewInt(1), 6)) < 0:
 		err = binary.Write(es, binary.LittleEndian, uint8(i.Int64()<<2))
 	case i.Cmp(new(big.Int).Lsh(big.NewInt(1), 14)) < 0:
@@ -247,6 +247,9 @@ func (es *encodeState) encodeBigInt(i *big.Int) (err error) {
 		if err == nil {
 			// write integer itself
 			err = binary.Write(es, binary.LittleEndian, reverseBytes(i.Bytes()))
+			if err != nil {
+				err = fmt.Errorf("writing bytes %s: %w", i, err)
+			}
 		}
 	}
 	return
@@ -299,7 +302,7 @@ func (es *encodeState) encodeFixedWidthInt(i interface{}) (err error) {
 	case uint64:
 		err = binary.Write(es, binary.LittleEndian, i)
 	default:
-		err = fmt.Errorf("could not encode fixed width integer, invalid type: %T", i)
+		err = fmt.Errorf("invalid type: %T", i)
 	}
 	return
 }
@@ -374,7 +377,7 @@ func (es *encodeState) encodeUint(i uint) (err error) {
 // encodeUint128 encodes a Uint128
 func (es *encodeState) encodeUint128(i *Uint128) (err error) {
 	if i == nil {
-		err = fmt.Errorf("uint128 is nil: %v", i)
+		err = fmt.Errorf("%w", errUint128IsNil)
 		return
 	}
 	err = binary.Write(es, binary.LittleEndian, padBytes(i.Bytes(), binary.LittleEndian))

pkg/scale/errors.go

@@ -6,5 +6,18 @@ package scale
 import "errors"
 
 var (
-	ErrVaryingDataTypeNotSet = errors.New("VaryingDataTypeValue has not been set")
+	ErrUnsupportedDestination          = errors.New("must be a non-nil pointer to a destination")
+	errDecodeBool                      = errors.New("invalid byte for bool")
+	ErrUnsupportedType                 = errors.New("unsupported type")
+	ErrUnsupportedResult               = errors.New("unsupported result")
+	errUnsupportedOption               = errors.New("unsupported option")
+	errUnknownVaryingDataTypeValue     = errors.New("unable to find VaryingDataTypeValue with index")
+	errUint128IsNil                    = errors.New("uint128 in nil")
+	ErrResultNotSet                    = errors.New("result not set")
+	ErrResultAlreadySet                = errors.New("result already has an assigned value")
+	ErrUnsupportedVaryingDataTypeValue = errors.New("unsupported VaryingDataTypeValue")
+	ErrMustProvideVaryingDataTypeValue = errors.New("must provide at least one VaryingDataTypeValue")
+	errBigIntIsNil                     = errors.New("big int is nil")
+	ErrVaryingDataTypeNotSet           = errors.New("varying data type not set")
+	ErrUnsupportedCustomPrimitive      = errors.New("unsupported type for custom primitive")
 )

pkg/scale/result.go

@@ -4,13 +4,10 @@
 package scale
 
 import (
-	"errors"
 	"fmt"
 	"reflect"
 )
 
-var ErrResultAlreadySet = errors.New("result already has an assigned value")
-
 // ResultMode is the mode the Result is set to
 type ResultMode int
 

pkg/scale/uint128.go

@@ -155,7 +155,7 @@ func (u *Uint128) UnmarshalJSON(data []byte) error {
 
 	dec, err := NewUint128(intVal)
 	if err != nil {
-		return err
+		return fmt.Errorf("creating uint128 from big integer: %w", err)
 	}
 	u.Upper = dec.Upper
 	u.Lower = dec.Lower

pkg/scale/varying_data_type.go

@@ -25,6 +25,7 @@ func (vdts *VaryingDataTypeSlice) Add(values ...VaryingDataTypeValue) (err error
 		copied := vdts.VaryingDataType
 		err = copied.Set(val)
 		if err != nil {
+			err = fmt.Errorf("setting VaryingDataTypeValue: %w", err)
 			return
 		}
 		vdts.Types = append(vdts.Types, copied)
@@ -43,7 +44,7 @@ func mustNewVaryingDataTypeSliceAndSet(vdt VaryingDataType,
 	values ...VaryingDataTypeValue) (vdts VaryingDataTypeSlice) {
 	vdts = NewVaryingDataTypeSlice(vdt)
 	if err := vdts.Add(values...); err != nil {
-		panic(err)
+		panic(fmt.Sprintf("adding varying data type value: %s", err))
 	}
 	return
 }
@@ -58,7 +59,7 @@ type VaryingDataType struct {
 func (vdt *VaryingDataType) Set(value VaryingDataTypeValue) (err error) {
 	_, ok := vdt.cache[value.Index()]
 	if !ok {
-		err = fmt.Errorf("unable to append VaryingDataTypeValue: %T, not in cache", value)
+		err = fmt.Errorf("%w: %v (%T)", ErrUnsupportedVaryingDataTypeValue, value, value)
 		return
 	}
 	vdt.value = value
@@ -76,7 +77,7 @@ func (vdt *VaryingDataType) Value() (VaryingDataTypeValue, error) {
 // NewVaryingDataType is constructor for VaryingDataType
 func NewVaryingDataType(values ...VaryingDataTypeValue) (vdt VaryingDataType, err error) {
 	if len(values) == 0 {
-		err = fmt.Errorf("must provide atleast one VaryingDataTypeValue")
+		err = fmt.Errorf("%w", ErrMustProvideVaryingDataTypeValue)
 		return
 	}
 	vdt.cache = make(map[uint]VaryingDataTypeValue)