update

copier.go

@@ -6,16 +6,33 @@ import (
 	"strings"
 	"sync"
 	"time"
-
-	"github.com/modern-go/reflect2"
 )
 
-func Copy(dst, src any, opts ...option) error {
-	opt := getOpt(opts...)
-	return copy(dst, src, opt)
+type copier struct {
+	opt     *options
+	visited map[reflect.Value]struct{}
 }
 
-func copy(dst, src any, opt *options) error {
+func newCopier(opts ...option) *copier {
+	opt := getOpt(opts...)
+	var visited map[reflect.Value]struct{}
+	if opt.detectCircularRefs {
+		visited = make(map[reflect.Value]struct{})
+	}
+
+	return &copier{
+		visited: visited,
+		opt:     opt,
+	}
+}
+
+func (c *copier) Copy(dst, src any) error {
+	defer c.reset()
+
+	if dst == nil || src == nil {
+		return ErrInvalidCopyDestination
+	}
+
 	var (
 		srcValue = indirect(reflect.ValueOf(src))
 		dstValue = indirect(reflect.ValueOf(dst))
@@ -29,36 +46,46 @@ func copy(dst, src any, opt *options) error {
 		return ErrInvalidCopyDestination
 	}
 
-	return deepCopy(dstValue, srcValue, 0, "", opt)
+	return c.deepCopy(dstValue, srcValue, 0)
 }
 
-func deepCopy(dst, src reflect.Value, depth int, fieldName string, opt *options) error {
+func (c *copier) reset() {
+	if c.opt.detectCircularRefs {
+		c.visited = make(map[reflect.Value]struct{})
+	}
+}
+
+func (c *copier) deepCopy(dst, src reflect.Value, depth int) error {
+	if c.ExceedMaxDepth(depth) {
+		return nil
+	}
+
 	if src.IsZero() {
 		return nil
 	}
 
-	if opt.ExceedMaxDepth(depth) {
-		return nil
-	}
-
-	// fmt.Println("do deep copy src:", src.Kind().String(), "dst:", dst.Kind().String())
 	switch src.Kind() {
 	case reflect.Slice, reflect.Array:
 		// slice -> slice
-		return copySlice(dst, src, depth, fieldName, opt)
+		switch dst.Kind() {
+		case reflect.Slice, reflect.Array:
+			return c.copySlice(dst, src, depth)
+		default:
+			return ErrNotSupported
+		}
 	case reflect.Map:
 		switch dst.Kind() {
 		case reflect.Map:
 			// map -> map
-			return copyMap(dst, src, depth, fieldName, opt)
+			return c.copyMap(dst, src, depth)
 		case reflect.Struct:
 			// map -> struct
-			return copyMap2Struct(dst, src, depth, fieldName, opt)
+			return c.copyMap2Struct(dst, src, depth)
 		case reflect.Pointer:
 			elemType := dst.Type().Elem()
 			newPtr := reflect.New(elemType)
 
-			if err := deepCopy(newPtr.Elem(), src, depth+1, fieldName, opt); err != nil {
+			if err := c.deepCopy(newPtr.Elem(), src, depth+1); err != nil {
 				return err
 			}
 
@@ -71,17 +98,17 @@ func deepCopy(dst, src reflect.Value, depth int, fieldName string, opt *options)
 		switch dst.Kind() {
 		case reflect.Map:
 			// struct -> map
-			return copyStruct2Map(dst, src, depth, fieldName, opt)
+			return c.copyStruct2Map(dst, src, depth)
 		case reflect.Struct:
 			// struct -> struct
-			return copyStruct(dst, src, depth, opt)
+			return c.copyStruct(dst, src, depth)
 		case reflect.Array, reflect.Slice:
 			if dst.IsNil() {
 				dstType := dst.Type().Elem()
 				newDst := reflect.MakeSlice(reflect.SliceOf(dstType), 1, 1)
 				dst.Set(newDst)
 
-				if err := deepCopy(dst.Index(0), src, depth+1, fieldName, opt); err != nil {
+				if err := c.deepCopy(dst.Index(0), src, depth+1); err != nil {
 					return err
 				}
 
@@ -92,7 +119,7 @@ func deepCopy(dst, src reflect.Value, depth int, fieldName string, opt *options)
 				reflect.Copy(newSlice, dst)
 
 				newDst := newSlice.Index(len)
-				if err := deepCopy(newDst, src, depth+1, fieldName, opt); err != nil {
+				if err := c.deepCopy(newDst, src, depth+1); err != nil {
 					return err
 				}
 				dst.Set(newSlice)
@@ -100,14 +127,9 @@ func deepCopy(dst, src reflect.Value, depth int, fieldName string, opt *options)
 
 			return nil
 		default:
-			return set(dst, src, fieldName, opt)
+			return c.set(dst, src)
 		}
 
-	case reflect.Func:
-		if dst.Kind() == reflect.Func && dst.IsNil() {
-			dst.Set(src)
-		}
-		return nil
 	case reflect.Pointer:
 		if dst.Kind() == reflect.Pointer && dst.IsNil() {
 			if !dst.CanSet() {
@@ -125,7 +147,7 @@ func deepCopy(dst, src reflect.Value, depth int, fieldName string, opt *options)
 			dst = dst.Elem()
 		}
 
-		return deepCopy(dst, src, depth, fieldName, opt)
+		return c.deepCopy(dst, src, depth)
 
 	case reflect.Interface:
 		if src.IsNil() {
@@ -133,26 +155,26 @@ func deepCopy(dst, src reflect.Value, depth int, fieldName string, opt *options)
 		}
 
 		if src.Kind() != dst.Kind() {
-			return set(dst, src, fieldName, opt)
+			return c.set(dst, src)
 		}
 
 		src = src.Elem()
 		newDst := reflect.New(src.Type().Elem())
 
-		if err := deepCopy(newDst, src, depth, fieldName, opt); err != nil {
+		if err := c.deepCopy(newDst, src, depth); err != nil {
 			return err
 		}
 
 		dst.Set(newDst)
 		return nil
-	case reflect.Chan:
+	case reflect.Chan, reflect.Func, reflect.UnsafePointer:
 		return ErrNotSupported
 	default:
-		return set(dst, src, fieldName, opt)
+		return c.set(dst, src)
 	}
 }
 
-func copyStruct2Map(dst, src reflect.Value, depth int, fieldName string, opt *options) error {
+func (c *copier) copyStruct2Map(dst, src reflect.Value, depth int) error {
 	for i, n := 0, src.NumField(); i < n; i++ {
 		sf := src.Type().Field(i)
 		if sf.PkgPath != "" && !sf.Anonymous {
@@ -162,7 +184,7 @@ func copyStruct2Map(dst, src reflect.Value, depth int, fieldName string, opt *op
 		if sf.Anonymous {
 			switch sf.Type.Kind() {
 			case reflect.Struct, reflect.Pointer:
-				if err := deepCopy(dst, src.Field(i), depth+1, fieldName, opt); err != nil {
+				if err := c.deepCopy(dst, src.Field(i), depth+1); err != nil {
 					return err
 				}
 			}
@@ -170,16 +192,16 @@ func copyStruct2Map(dst, src reflect.Value, depth int, fieldName string, opt *op
 			continue
 		}
 
-		tag := parseTag(sf.Tag.Get(opt.tagName))
+		tag := parseTag(sf.Tag.Get(c.opt.tagName))
 		if tag.Contains(tagIgnore) {
 			continue
 		}
 
-		name := getFieldName(sf.Name, tag, opt)
+		name := c.getFieldName(sf.Name, tag)
 
 		sField := src.Field(i)
 
-		if opt.ignoreEmpty && sField.IsZero() {
+		if c.opt.ignoreEmpty && sField.IsZero() {
 			continue
 		}
 
@@ -187,7 +209,7 @@ func copyStruct2Map(dst, src reflect.Value, depth int, fieldName string, opt *op
 			var newDst = reflect.ValueOf(make(map[string]any))
 			sField = indirect(sField)
 
-			if err := deepCopy(newDst, sField, depth+1, name, opt); err != nil {
+			if err := c.deepCopy(newDst, sField, depth+1); err != nil {
 				return err
 			}
 
@@ -200,11 +222,9 @@ func copyStruct2Map(dst, src reflect.Value, depth int, fieldName string, opt *op
 	return nil
 }
 
-func copyMap2Struct(dst, src reflect.Value, depth int, _ string, opt *options) error {
-	// 循环结构，然后从map取值
+func (c *copier) copyMap2Struct(dst, src reflect.Value, depth int) error {
 	typ := dst.Type()
-
-	for i, n := 0, src.NumField(); i < n; i++ {
+	for i, n := 0, dst.NumField(); i < n; i++ {
 		field := dst.Field(i)
 		sf := typ.Field(i)
 
@@ -213,15 +233,12 @@ func copyMap2Struct(dst, src reflect.Value, depth int, _ string, opt *options) e
 		}
 
 		if sf.Anonymous {
-			if err := deepCopy(field, src, depth+1, sf.Name, opt); err != nil {
+			if err := c.deepCopy(field, src, depth+1); err != nil {
 				return err
 			}
 		}
 
-		name := getFieldNameFromJsonTag(sf)
-		if name == "-" {
-			continue
-		}
+		name := sf.Name
 
 		mapValue := src.MapIndex(reflect.ValueOf(name))
 		if !mapValue.IsValid() {
@@ -233,11 +250,11 @@ func copyMap2Struct(dst, src reflect.Value, depth int, _ string, opt *options) e
 		}
 
 		if mapValue.Kind() == reflect.Map || mapValue.Kind() == reflect.Array || mapValue.Kind() == reflect.Slice {
-			if err := deepCopy(field, mapValue, depth+1, name, opt); err != nil {
+			if err := c.deepCopy(field, mapValue, depth+1); err != nil {
 				return err
 			}
 		} else {
-			if err := set(field, mapValue, name, opt); err != nil {
+			if err := c.set(field, mapValue); err != nil {
 				return err
 			}
 		}
@@ -246,7 +263,7 @@ func copyMap2Struct(dst, src reflect.Value, depth int, _ string, opt *options) e
 	return nil
 }
 
-func copyMap(dst, src reflect.Value, depth int, fieldName string, opt *options) error {
+func (c *copier) copyMap(dst, src reflect.Value, depth int) error {
 	if dst.IsNil() {
 		dst.Set(reflect.MakeMapWithSize(dst.Type(), src.Len()))
 	}
@@ -259,11 +276,11 @@ func copyMap(dst, src reflect.Value, depth int, fieldName string, opt *options)
 		value := iter.Value()
 
 		if name, ok := key.Interface().(string); ok {
-			fieldName = opt.NameConvert(name)
+			fieldName := c.getFieldName(name, nil)
 			key = reflect.ValueOf(fieldName)
 		}
 
-		if opt.ignoreEmpty && value.IsZero() {
+		if c.opt.ignoreEmpty && value.IsZero() {
 			continue
 		}
 
@@ -277,12 +294,12 @@ func copyMap(dst, src reflect.Value, depth int, fieldName string, opt *options)
 				copitedValue = reflect.New(value.Type()).Elem()
 			}
 
-			set(copitedValue, value, fieldName, opt)
+			c.set(copitedValue, value)
 		default:
 			copitedValue = reflect.New(dstType.Elem()).Elem()
 		}
 
-		if err := deepCopy(copitedValue, value, depth+1, fieldName, opt); err != nil {
+		if err := c.deepCopy(copitedValue, value, depth+1); err != nil {
 			return err
 		}
 
@@ -292,28 +309,40 @@ func copyMap(dst, src reflect.Value, depth int, fieldName string, opt *options)
 	return nil
 }
 
-func copySlice(dst, src reflect.Value, depth int, fieldName string, opt *options) error {
-	len := src.Len()
+func (c *copier) copySlice(dst, src reflect.Value, depth int) error {
+	var len int
+	if src.Kind() == reflect.Struct {
+		len = 0
+	} else {
+		len = src.Len()
+	}
+
 	if dst.Len() > 0 && dst.Len() < src.Len() {
 		len = dst.Len()
 	}
 
-	if dst.Kind() == reflect.Slice && dst.Len() == 0 && src.Len() > 0 {
+	if dst.Kind() == reflect.Slice && dst.Len() == 0 && len > 0 {
 		dstType := dst.Type().Elem()
 		newDst := reflect.MakeSlice(reflect.SliceOf(dstType), len, len)
 		dst.Set(newDst)
 	}
 
-	for i := 0; i < len; i++ {
-		if err := deepCopy(dst.Index(i), src.Index(i), depth, fieldName, opt); err != nil {
+	if src.Kind() == reflect.Struct {
+		if err := c.deepCopy(dst.Index(0), src, depth); err != nil {
 			return err
 		}
+	} else {
+		for i := 0; i < len; i++ {
+			if err := c.deepCopy(dst.Index(i), src.Index(i), depth); err != nil {
+				return err
+			}
+		}
 	}
 
 	return nil
 }
 
-func copyStruct(dst, src reflect.Value, depth int, opt *options) error {
+func (c *copier) copyStruct(dst, src reflect.Value, depth int) error {
 	if dst.CanSet() {
 		if _, ok := src.Interface().(time.Time); ok {
 			dst.Set(src)
@@ -322,41 +351,42 @@ func copyStruct(dst, src reflect.Value, depth int, opt *options) error {
 	}
 
 	typ := src.Type()
-	fields := deepFields(typ)
+	fields := c.deepFields(typ)
 	for _, sf := range fields {
-		tag := parseTag(sf.Tag.Get(opt.tagName))
-		if tag.Contains(tagIgnore) {
-			continue
-		}
-
-		name := getFieldName(sf.Name, tag, opt)
+		name := c.getFieldName(sf.Field.Name, sf.Tag)
 
 		if nestedAnonymousField(dst, name) {
 			continue
 		}
 
-		typ := reflect2.TypeOf(dst)
-		dstPtr := reflect2.PtrOf(dst)
-		typ.(reflect2.StructType).Field(1).UnsafeGet(dstPtr)
-
-		dstValue := fieldByName(dst, name, opt)
+		dstValue := c.fieldByName(dst, name)
 		if !dstValue.IsValid() {
 			continue
 		}
 
-		sField := src.FieldByName(sf.Name)
-		if opt.ignoreEmpty && sField.IsZero() {
+		if c.isCricularRefs(dstValue) {
 			continue
 		}
 
-		if err := deepCopy(dstValue, sField, depth+1, name, opt); err != nil {
+		sField := src.FieldByName(sf.Field.Name)
+		if c.opt.ignoreEmpty && sField.IsZero() {
+			continue
+		}
+
+		if ok, err := c.lookupAndCopyWithConverter(dstValue, sField, name); err != nil {
+			return err
+		} else if ok {
+			return nil
+		}
+
+		if err := c.deepCopy(dstValue, sField, depth+1); err != nil {
 			return err
 		}
 	}
 	return nil
 }
 
-func set(dst, src reflect.Value, fieldName string, opt *options) error {
+func (c *copier) set(dst, src reflect.Value) error {
 	if !src.IsValid() {
 		return ErrInvalidCopyFrom
 	}
@@ -365,11 +395,11 @@ func set(dst, src reflect.Value, fieldName string, opt *options) error {
 		src = src.Elem()
 	}
 
-	if ok, err := lookupAndCopyWithConverter(dst, src, fieldName, opt); err != nil {
-		return err
-	} else if ok {
-		return nil
-	}
+	// if ok, err := c.lookupAndCopyWithConverter(dst, src, fieldName); err != nil {
+	// 	return err
+	// } else if ok {
+	// 	return nil
+	// }
 
 	if dst.Kind() == reflect.Pointer {
 		if dst.IsNil() {
@@ -465,17 +495,23 @@ func set(dst, src reflect.Value, fieldName string, opt *options) error {
 }
 
 type fieldsWrapper struct {
-	Fields []reflect.StructField
+	Fields []fieldWrapper
 	once   sync.Once
 }
 
+type fieldWrapper struct {
+	Field reflect.StructField
+	Tag   *tagOption
+	Index int
+}
+
 var deepFieldsMap sync.Map
 
-func deepFields(reflectType reflect.Type) []reflect.StructField {
+func (c *copier) deepFields(reflectType reflect.Type) []fieldWrapper {
 	if wrapper, ok := deepFieldsMap.Load(reflectType); ok {
 		w := wrapper.(*fieldsWrapper)
 		w.once.Do(func() {
-			w.Fields = calculateDeepFields(reflectType)
+			w.Fields = c.calculateDeepFields(reflectType)
 		})
 		return w.Fields
 	}
@@ -484,7 +520,7 @@ func deepFields(reflectType reflect.Type) []reflect.StructField {
 	w := wrapper.(*fieldsWrapper)
 	if !loaded {
 		w.once.Do(func() {
-			w.Fields = calculateDeepFields(reflectType)
+			w.Fields = c.calculateDeepFields(reflectType)
 		})
 	} else {
 		w.once.Do(func() {})
@@ -493,10 +529,10 @@ func deepFields(reflectType reflect.Type) []reflect.StructField {
 	return w.Fields
 }
 
-func calculateDeepFields(reflectType reflect.Type) []reflect.StructField {
+func (c *copier) calculateDeepFields(reflectType reflect.Type) []fieldWrapper {
 	reflectType, _ = indirectType(reflectType)
 	num := reflectType.NumField()
-	res := make([]reflect.StructField, 0, num)
+	res := make([]fieldWrapper, 0, num)
 	if reflectType.Kind() == reflect.Struct {
 		for i := range num {
 			sf := reflectType.Field(i)
@@ -504,11 +540,13 @@ func calculateDeepFields(reflectType reflect.Type) []reflect.StructField {
 				continue
 			}
 
+			tag := parseTag(sf.Tag.Get(c.opt.tagName))
+
 			if sf.Anonymous {
-				res = append(res, deepFields(sf.Type)...)
+				res = append(res, c.deepFields(sf.Type)...)
 			}
 
-			res = append(res, sf)
+			res = append(res, fieldWrapper{Field: sf, Tag: tag, Index: i})
 		}
 	}
 
@@ -540,18 +578,18 @@ func nestedAnonymousField(dst reflect.Value, fieldName string) bool {
 	return false
 }
 
-func lookupAndCopyWithConverter(dst, src reflect.Value, fieldName string, opt *options) (bool, error) {
-	if cnv, ok := opt.convertByName[fieldName]; ok {
+func (c *copier) lookupAndCopyWithConverter(dst, src reflect.Value, fieldName string) (bool, error) {
+	if cnv, ok := c.opt.convertByName[fieldName]; ok {
 		return convert(dst, src, cnv)
 	}
 
-	if len(opt.converters) > 0 {
+	if len(c.opt.converters) > 0 {
 		pair := converterPair{
 			SrcType: src.Type(),
 			DstType: dst.Type(),
 		}
 
-		if cnv, ok := opt.converters[pair]; ok {
+		if cnv, ok := c.opt.converters[pair]; ok {
 			return convert(dst, src, cnv)
 		}
 	}
@@ -575,36 +613,37 @@ func convert(dst, src reflect.Value, fn convertFunc) (bool, error) {
 
 }
 
-func getFieldNameFromJsonTag(field reflect.StructField) string {
-	if tag := field.Tag.Get("json"); tag != "" {
-		if commaIndex := strings.Index(tag, ","); commaIndex != -1 {
-			name := tag[:commaIndex]
-			if name != "" {
-				return name
-			}
-		} else if tag != "" {
-			return tag
-		}
-	}
-
-	return field.Name
-}
-
-func getFieldName(name string, tag *tagOption, opt *options) string {
+func (c *copier) getFieldName(name string, tag *tagOption) string {
 	if tag != nil && tag.Contains(tagToName) {
 		return tag.toname
 	}
 
-	return opt.NameConvert(name)
+	return c.opt.NameConvert(name)
 }
 
-func fieldByName(v reflect.Value, name string, opt *options) reflect.Value {
-	if opt != nil && opt.caseSensitive {
+func (c *copier) fieldByName(v reflect.Value, name string) reflect.Value {
+	if c.opt != nil && c.opt.caseSensitive {
 		return v.FieldByName(name)
 	}
 	return v.FieldByNameFunc(func(s string) bool { return strings.EqualFold(s, name) })
 }
 
+func (c *copier) ExceedMaxDepth(depth int) bool {
+	return c.opt.maxDepth > 0 && depth >= c.opt.maxDepth
+}
+
+func (c *copier) isCricularRefs(reflectValue reflect.Value) bool {
+	if c.opt.detectCircularRefs {
+		_, ok := c.visited[reflectValue.Addr()]
+		if !ok {
+			c.visited[reflectValue.Addr()] = struct{}{}
+		}
+		return ok
+	}
+
+	return false
+}
+
 func indirect(reflectValue reflect.Value) reflect.Value {
 	for reflectValue.Kind() == reflect.Pointer {
 		reflectValue = reflectValue.Elem()

copier_slice_test.go

@@ -75,3 +75,42 @@ func TestAndSlice(t *testing.T) {
 		t.Errorf("Expected %v, got %v", []string{"developer", "golang", "backend"}, dst)
 	}
 }
+
+func TestStructAppendSlice(t *testing.T) {
+	type person struct {
+		Name string
+		Age  int
+	}
+
+	src := person{Name: "Alice", Age: 20}
+
+	dst := []person{
+		{Name: "Charlie", Age: 40},
+	}
+
+	if err := Copy(&dst, src); err != nil {
+		t.Fatal(err)
+	}
+
+	if len(dst) != 2 {
+		t.Errorf("Expected %d elements, got %d", 2, len(dst))
+	}
+
+	t.Log(dst)
+}
+
+func TestAppendSlice(t *testing.T) {
+	src := []string{"developer", "golang", "backend"}
+	dst := []any{"do"}
+
+	if err := Copy(&dst, src); err != nil {
+		t.Fatal(err)
+	}
+
+	t.Log(dst)
+
+	if !slices.Equal([]any{"do", "developer", "golang", "backend"}, dst) {
+		t.Errorf("Expected %v, got %v", []string{"do", "developer", "golang", "backend"}, dst)
+	}
+
+}

copier_test.go

@@ -2,6 +2,7 @@ package copier
 
 import (
 	"fmt"
+	"reflect"
 	"testing"
 	"time"
 )
@@ -22,6 +23,12 @@ type Person2 struct {
 	Age  int
 }
 
+type Employee struct {
+	Name    string
+	Age     int
+	Address *Address
+}
+
 func TestCopySameStruct(t *testing.T) {
 	src := &Person{
 		Name: "John",
@@ -282,3 +289,37 @@ func TestTypeConvert(t *testing.T) {
 	}
 	t.Log("src,dst:", src, dst)
 }
+
+func TestDeepFileds(t *testing.T) {
+	var emp = Employee{}
+	typ := reflect.TypeOf(emp)
+
+	copier := newCopier()
+	wrapper := copier.deepFields(typ)
+	for _, v := range wrapper {
+		t.Log(v, v.Index)
+	}
+}
+
+func BenchmarkCopy(b *testing.B) {
+	var emp = Employee{
+		Name: "John",
+		Age:  30,
+	}
+
+	for b.Loop() {
+		var dst Employee
+		Copy(&dst, &emp)
+	}
+}
+
+func BenchmarkDeepFields(b *testing.B) {
+	var emp = Employee{}
+	typ := reflect.TypeOf(emp)
+
+	for b.Loop() {
+		copier := newCopier()
+		copier.deepFields(typ)
+	}
+
+}

deepcopier.go

@@ -0,0 +1,20 @@
+package copier
+
+import "reflect"
+
+func Copy(dst, src any, opts ...option) error {
+	copier := newCopier(opts...)
+	return copier.Copy(dst, src)
+}
+
+func Clone(src any, opts ...option) (any, error) {
+	if src == nil {
+		return nil, nil
+	}
+
+	srcType := reflect.TypeOf(src)
+	dst := reflect.New(srcType).Interface()
+
+	err := newCopier(opts...).Copy(dst, src)
+	return dst, err
+}

go.mod

@@ -1,3 +1,3 @@
 module git.charlienet.top/go/copier
 
-go 1.25
+go 1.24

optiongs.go

@@ -9,15 +9,16 @@ const (
 type convertFunc func(any) (any, error)
 
 type options struct {
-	tagName          string                        // 标签名
-	maxDepth         int                           // 最大复制深度
-	ignoreEmpty      bool                          // 复制时忽略空字段
-	caseSensitive    bool                          // 复制时大小写敏感
-	must             bool                          // 只复制具有must标识的字段
-	fieldNameMapping map[string]string             // 字段名转映射
-	nameConverter    func(string) string           // 字段名转换函数
-	converters       map[converterPair]convertFunc // 根据源和目标类型处理的类型转换器v
-	convertByName    map[string]convertFunc        // 根据名称处理的类型转换器
+	tagName            string                        // 标签名
+	maxDepth           int                           // 最大复制深度
+	ignoreEmpty        bool                          // 复制时忽略空字段
+	caseSensitive      bool                          // 复制时大小写敏感
+	must               bool                          // 只复制具有must标识的字段
+	detectCircularRefs bool                          // 检测循环引用
+	fieldNameMapping   map[string]string             // 字段名转映射
+	converters         map[converterPair]convertFunc // 根据源和目标类型处理的类型转换器v
+	convertByName      map[string]convertFunc        // 根据名称处理的类型转换器
+	nameConverter      func(string) string           // 字段名转换函数
 }
 
 type option func(*options)
@@ -37,10 +38,8 @@ type converterPair struct {
 
 func getOpt(opts ...option) *options {
 	opt := &options{
-		maxDepth:      noDepthLimited,
-		tagName:       defaultTag,
-		convertByName: make(map[string]convertFunc),
-		converters:    make(map[converterPair]convertFunc),
+		maxDepth: noDepthLimited,
+		tagName:  defaultTag,
 	}
 
 	for _, o := range opts {
@@ -94,16 +93,44 @@ func WithMust() option {
 	}
 }
 
+// WithDetectCircularRefs 添加检测循环引用标识
+func WithDetectCircularRefs() option {
+	return func(o *options) {
+		o.detectCircularRefs = true
+	}
+}
+
 // WithNameConvertByName 添加根据名称处理的类型转换器
 func WithTypeConvertByName(name string, f func(src any) (dst any, err error)) option {
 	return func(o *options) {
+		if o.convertByName == nil {
+			o.convertByName = make(map[string]convertFunc)
+		}
+
 		o.convertByName[name] = f
 	}
 }
 
+// WithConvertByNames 添加根据名称处理的类型转换器
+func WithTypeConvertByNames(nameConvert map[string]func(src any) (dst any, err error)) option {
+	return func(o *options) {
+		if o.convertByName == nil {
+			o.convertByName = make(map[string]convertFunc)
+		}
+
+		for name, nameConvert := range nameConvert {
+			o.convertByName[name] = nameConvert
+		}
+	}
+}
+
 // WithTypeConvert 添加根据源和目标类型处理的类型转换器
 func WithConverters(converters ...TypeConverter) option {
 	return func(o *options) {
+		if len(converters) > 0 && o.converters == nil {
+			o.converters = make(map[converterPair]convertFunc)
+		}
+
 		for i := range converters {
 			pair := converterPair{
 				SrcType: reflect.TypeOf(converters[i].SrcType),