Merge pull request #114 from goccy/feature/support-json-encoding

Supports encoding in JSON format

encode.go

@@ -30,6 +30,7 @@ type Encoder struct {
 	opts               []EncodeOption
 	indent             int
 	isFlowStyle        bool
+	isJSONStyle        bool
 	anchorCallback     func(*ast.AnchorNode, interface{}) error
 	anchorPtrToNameMap map[uintptr]string
 
@@ -242,7 +243,7 @@ func (e *Encoder) encodeFloat(v float64) ast.Node {
 }
 
 func (e *Encoder) encodeString(v string, column int) ast.Node {
-	if token.IsNeedQuoted(v) {
+	if e.isJSONStyle || token.IsNeedQuoted(v) {
 		v = strconv.Quote(v)
 	}
 	return ast.String(token.New(v, v, e.pos(column)))
@@ -368,6 +369,9 @@ func (e *Encoder) isZeroValue(v reflect.Value) bool {
 
 func (e *Encoder) encodeTime(v time.Time, column int) ast.Node {
 	value := v.Format(time.RFC3339Nano)
+	if e.isJSONStyle {
+		value = strconv.Quote(value)
+	}
 	return ast.String(token.New(value, value, e.pos(column)))
 }
 

encode_test.go

@@ -695,6 +695,52 @@ func TestEncoder_Flow(t *testing.T) {
 	}
 }
 
+func TestEncoder_JSON(t *testing.T) {
+	var buf bytes.Buffer
+	enc := yaml.NewEncoder(&buf, yaml.JSON())
+	type st struct {
+		I int8
+		S string
+		F float32
+	}
+	if err := enc.Encode(struct {
+		I      int
+		U      uint
+		S      string
+		F      float64
+		Struct *st
+		Slice  []int
+		Map    map[string]interface{}
+		Time   time.Time
+	}{
+		I: -10,
+		U: 10,
+		S: "hello",
+		F: 3.14,
+		Struct: &st{
+			I: 2,
+			S: "world",
+			F: 1.23,
+		},
+		Slice: []int{1, 2, 3, 4, 5},
+		Map: map[string]interface{}{
+			"a": 1,
+			"b": 1.23,
+			"c": "json",
+		},
+		Time: time.Time{},
+	}); err != nil {
+		t.Fatalf("%+v", err)
+	}
+	expect := `
+{"i": -10, "u": 10, "s": "hello", "f": 3.14, "struct": {"i": 2, "s": "world", "f": 1.23}, "slice": [1, 2, 3, 4, 5], "map": {"a": 1, "b": 1.23, "c": "json"}, "time": "0001-01-01T00:00:00Z"}
+`
+	actual := "\n" + buf.String()
+	if expect != actual {
+		t.Fatalf("JSON style marshal error: expect=[%s] actual=[%s]", expect, actual)
+	}
+}
+
 func TestEncoder_MarshalAnchor(t *testing.T) {
 	type Host struct {
 		Hostname string

option.go

@@ -104,6 +104,15 @@ func Flow(isFlowStyle bool) EncodeOption {
 	}
 }
 
+// JSON encode in JSON format
+func JSON() EncodeOption {
+	return func(e *Encoder) error {
+		e.isJSONStyle = true
+		e.isFlowStyle = true
+		return nil
+	}
+}
+
 // MarshalAnchor call back if encoder find an anchor during encoding
 func MarshalAnchor(callback func(*ast.AnchorNode, interface{}) error) EncodeOption {
 	return func(e *Encoder) error {