encoding/xml: marshal/unmarshal xml.Name in field

R=rsc
CC=golang-dev
https://golang.org/cl/5542052

src/pkg/encoding/xml/marshal_test.go

@@ -150,6 +150,10 @@ type XMLNameWithoutTag struct {
 	Value   string ",chardata"
 }
 
+type NameInField struct {
+	Foo Name `xml:"ns foo"`
+}
+
 type AttrTest struct {
 	Int   int     `xml:",attr"`
 	Lower int     `xml:"int,attr"`
@@ -483,6 +487,19 @@ var marshalTests = []struct {
 		UnmarshalOnly: true,
 	},
 
+	// xml.Name works in a plain field as well.
+	{
+		Value:     &NameInField{Name{Space: "ns", Local: "foo"}},
+		ExpectXML: `<NameInField><foo xmlns="ns"></foo></NameInField>`,
+	},
+
+	// Marshaling zero xml.Name uses the tag or field name.
+	{
+		Value:       &NameInField{},
+		ExpectXML:   `<NameInField><foo xmlns="ns"></foo></NameInField>`,
+		MarshalOnly: true,
+	},
+
 	// Test attributes
 	{
 		Value: &AttrTest{

src/pkg/encoding/xml/read.go

@@ -271,6 +271,10 @@ func (p *Parser) unmarshal(val reflect.Value, start *StartElement) error {
 	case reflect.Struct:
 		sv = v
 		typ := sv.Type()
+		if typ == nameType {
+			v.Set(reflect.ValueOf(start.Name))
+			break
+		}
 		tinfo, err = getTypeInfo(typ)
 		if err != nil {
 			return err

src/pkg/encoding/xml/typeinfo.go

@@ -46,6 +46,8 @@ const (
 var tinfoMap = make(map[reflect.Type]*typeInfo)
 var tinfoLock sync.RWMutex
 
+var nameType = reflect.TypeOf(Name{})
+
 // getTypeInfo returns the typeInfo structure with details necessary
 // for marshalling and unmarshalling typ.
 func getTypeInfo(typ reflect.Type) (*typeInfo, error) {
@@ -56,7 +58,7 @@ func getTypeInfo(typ reflect.Type) (*typeInfo, error) {
 		return tinfo, nil
 	}
 	tinfo = &typeInfo{}
-	if typ.Kind() == reflect.Struct {
+	if typ.Kind() == reflect.Struct && typ != nameType {
 		n := typ.NumField()
 		for i := 0; i < n; i++ {
 			f := typ.Field(i)