util: add YAML marshaler to Fixed8

pkg/util/fixed8.go

@@ -87,8 +87,20 @@ func Fixed8FromString(s string) (Fixed8, error) {
 
 // UnmarshalJSON implements the json unmarshaller interface.
 func (f *Fixed8) UnmarshalJSON(data []byte) error {
+	return f.unmarshalHelper(func(v interface{}) error {
+		return json.Unmarshal(data, v)
+	})
+}
+
+// UnmarshalYAML implements the yaml unmarshaler interface.
+func (f *Fixed8) UnmarshalYAML(unmarshal func(interface{}) error) error {
+	return f.unmarshalHelper(unmarshal)
+}
+
+// unmarshalHelper is an underlying unmarshaller func for JSON and YAML.
+func (f *Fixed8) unmarshalHelper(unmarshal func(interface{}) error) error {
 	var s string
-	if err := json.Unmarshal(data, &s); err == nil {
+	if err := unmarshal(&s); err == nil {
 		p, err := Fixed8FromString(s)
 		if err != nil {
 			return err
@@ -98,7 +110,7 @@ func (f *Fixed8) UnmarshalJSON(data []byte) error {
 	}
 
 	var fl float64
-	if err := json.Unmarshal(data, &fl); err != nil {
+	if err := unmarshal(&fl); err != nil {
 		return err
 	}
 
@@ -111,6 +123,11 @@ func (f Fixed8) MarshalJSON() ([]byte, error) {
 	return []byte(`"` + f.String() + `"`), nil
 }
 
+// MarshalYAML implements the yaml marshaller interface.
+func (f Fixed8) MarshalYAML() (interface{}, error) {
+	return f.String(), nil
+}
+
 // DecodeBinary implements the io.Serializable interface.
 func (f *Fixed8) DecodeBinary(r *io.BinReader) {
 	*f = Fixed8(r.ReadU64LE())

pkg/util/fixed8_test.go

@@ -6,6 +6,7 @@ import (
 	"testing"
 
 	"github.com/CityOfZion/neo-go/pkg/io"
+	"github.com/go-yaml/yaml"
 	"github.com/stretchr/testify/assert"
 	"github.com/stretchr/testify/require"
 )
@@ -125,6 +126,19 @@ func TestFixed8_MarshalJSON(t *testing.T) {
 	assert.Equal(t, []byte(`"123.4"`), s)
 }
 
+func TestFixed8_UnmarshalYAML(t *testing.T) {
+	u, err := Fixed8FromString("123.4")
+	assert.NoError(t, err)
+
+	s, err := yaml.Marshal(u)
+	assert.NoError(t, err)
+	assert.Equal(t, []byte("\"123.4\"\n"), s) // yaml marshaler inserts LF at the end
+
+	var f Fixed8
+	assert.NoError(t, yaml.Unmarshal([]byte(`"123.4"`), &f))
+	assert.Equal(t, u, f)
+}
+
 func TestFixed8_Arith(t *testing.T) {
 	u1 := Fixed8FromInt64(3)
 	u2 := Fixed8FromInt64(8)