support naming strategy

extra/naming_strategy.go

@@ -0,0 +1,39 @@
+package extra
+
+import (
+	"github.com/json-iterator/go"
+	"unicode"
+)
+
+func SetNamingStrategy(translate func(string) string) {
+	jsoniter.RegisterExtension(&namingStrategyExtension{jsoniter.DummyExtension{}, translate})
+}
+
+type namingStrategyExtension struct {
+	jsoniter.DummyExtension
+	translate func(string) string
+}
+
+func (extension *namingStrategyExtension) UpdateStructDescriptor(structDescriptor *jsoniter.StructDescriptor) {
+	for _, binding := range structDescriptor.Fields {
+		binding.ToNames = []string{extension.translate(binding.Field.Name)}
+		binding.FromNames = []string{extension.translate(binding.Field.Name)}
+	}
+}
+
+func LowerCaseWithUnderscores(name string) string {
+	newName := []rune{}
+	for i, c := range name {
+		if i == 0 {
+			newName = append(newName, unicode.ToLower(c))
+		} else {
+			if unicode.IsUpper(c) {
+				newName = append(newName, '_')
+				newName = append(newName, unicode.ToLower(c))
+			} else {
+				newName = append(newName, c)
+			}
+		}
+	}
+	return string(newName)
+}

extra/naming_strategy_test.go

@@ -0,0 +1,23 @@
+package extra
+
+import (
+	"testing"
+	"github.com/json-iterator/go"
+	"github.com/json-iterator/go/require"
+)
+
+func Test_lower_case_with_underscores(t *testing.T) {
+	should := require.New(t)
+	should.Equal("hello_world", LowerCaseWithUnderscores("helloWorld"))
+	should.Equal("hello_world", LowerCaseWithUnderscores("HelloWorld"))
+	SetNamingStrategy(LowerCaseWithUnderscores)
+	output, err := jsoniter.MarshalToString(struct {
+		HelloWorld string
+	}{
+		HelloWorld: "hi",
+	})
+	should.Nil(err)
+	should.Equal(`{"hello_world":"hi"}`, output)
+}
+
+

jsoniter_adapter_test.go

@@ -60,3 +60,11 @@ func Test_use_number(t *testing.T) {
 	should.Nil(decoder2.Decode(&obj2))
 	should.Equal(json.Number("123"), obj2)
 }
+
+func Test_use_number_for_unmarshal(t *testing.T) {
+	should := require.New(t)
+	api := Config{UseNumber: true}.Froze()
+	var obj interface{}
+	should.Nil(api.UnmarshalFromString("123", &obj))
+	should.Equal(json.Number("123"), obj)
+}