internal/impl: simplify getMessageInfo
Our specific protoreflect.Message implementations have a special
ProtoMessageInfo method to obtain the *MessageInfo for v1 compatibility.
Use that instead to implement getMessageInfo.
Change-Id: I6cab9aeaa93714be73bd812c3d9a3be0ec86dd52
Reviewed-on: https://go-review.googlesource.com/c/protobuf/+/187777
Reviewed-by: Damien Neil <dneil@google.com>
diff --git a/internal/impl/codec_field.go b/internal/impl/codec_field.go
index 94b7d6a..9d587d2 100644
--- a/internal/impl/codec_field.go
+++ b/internal/impl/codec_field.go
@@ -79,19 +79,19 @@
}
func makeMessageFieldCoder(fd pref.FieldDescriptor, ft reflect.Type) pointerCoderFuncs {
- if fi, ok := getMessageInfo(ft); ok {
+ if mi := getMessageInfo(ft); mi != nil {
return pointerCoderFuncs{
size: func(p pointer, tagsize int, opts marshalOptions) int {
- return sizeMessageInfo(p, fi, tagsize, opts)
+ return sizeMessageInfo(p, mi, tagsize, opts)
},
marshal: func(b []byte, p pointer, wiretag uint64, opts marshalOptions) ([]byte, error) {
- return appendMessageInfo(b, p, wiretag, fi, opts)
+ return appendMessageInfo(b, p, wiretag, mi, opts)
},
unmarshal: func(b []byte, p pointer, wtyp wire.Type, opts unmarshalOptions) (int, error) {
- return consumeMessageInfo(b, p, fi, wtyp, opts)
+ return consumeMessageInfo(b, p, mi, wtyp, opts)
},
isInit: func(p pointer) error {
- return fi.isInitializedPointer(p.Elem())
+ return mi.isInitializedPointer(p.Elem())
},
}
} else {
@@ -200,19 +200,19 @@
func makeGroupFieldCoder(fd pref.FieldDescriptor, ft reflect.Type) pointerCoderFuncs {
num := fd.Number()
- if fi, ok := getMessageInfo(ft); ok {
+ if mi := getMessageInfo(ft); mi != nil {
return pointerCoderFuncs{
size: func(p pointer, tagsize int, opts marshalOptions) int {
- return sizeGroupType(p, fi, tagsize, opts)
+ return sizeGroupType(p, mi, tagsize, opts)
},
marshal: func(b []byte, p pointer, wiretag uint64, opts marshalOptions) ([]byte, error) {
- return appendGroupType(b, p, wiretag, fi, opts)
+ return appendGroupType(b, p, wiretag, mi, opts)
},
unmarshal: func(b []byte, p pointer, wtyp wire.Type, opts unmarshalOptions) (int, error) {
- return consumeGroupType(b, p, fi, num, wtyp, opts)
+ return consumeGroupType(b, p, mi, num, wtyp, opts)
},
isInit: func(p pointer) error {
- return fi.isInitializedPointer(p.Elem())
+ return mi.isInitializedPointer(p.Elem())
},
}
} else {
@@ -303,19 +303,19 @@
}
func makeMessageSliceFieldCoder(fd pref.FieldDescriptor, ft reflect.Type) pointerCoderFuncs {
- if fi, ok := getMessageInfo(ft); ok {
+ if mi := getMessageInfo(ft); mi != nil {
return pointerCoderFuncs{
size: func(p pointer, tagsize int, opts marshalOptions) int {
- return sizeMessageSliceInfo(p, fi, tagsize, opts)
+ return sizeMessageSliceInfo(p, mi, tagsize, opts)
},
marshal: func(b []byte, p pointer, wiretag uint64, opts marshalOptions) ([]byte, error) {
- return appendMessageSliceInfo(b, p, wiretag, fi, opts)
+ return appendMessageSliceInfo(b, p, wiretag, mi, opts)
},
unmarshal: func(b []byte, p pointer, wtyp wire.Type, opts unmarshalOptions) (int, error) {
- return consumeMessageSliceInfo(b, p, fi, wtyp, opts)
+ return consumeMessageSliceInfo(b, p, mi, wtyp, opts)
},
isInit: func(p pointer) error {
- return isInitMessageSliceInfo(p, fi)
+ return isInitMessageSliceInfo(p, mi)
},
}
}
@@ -471,19 +471,19 @@
func makeGroupSliceFieldCoder(fd pref.FieldDescriptor, ft reflect.Type) pointerCoderFuncs {
num := fd.Number()
- if fi, ok := getMessageInfo(ft); ok {
+ if mi := getMessageInfo(ft); mi != nil {
return pointerCoderFuncs{
size: func(p pointer, tagsize int, opts marshalOptions) int {
- return sizeGroupSliceInfo(p, fi, tagsize, opts)
+ return sizeGroupSliceInfo(p, mi, tagsize, opts)
},
marshal: func(b []byte, p pointer, wiretag uint64, opts marshalOptions) ([]byte, error) {
- return appendGroupSliceInfo(b, p, wiretag, fi, opts)
+ return appendGroupSliceInfo(b, p, wiretag, mi, opts)
},
unmarshal: func(b []byte, p pointer, wtyp wire.Type, opts unmarshalOptions) (int, error) {
- return consumeGroupSliceInfo(b, p, num, wtyp, fi, opts)
+ return consumeGroupSliceInfo(b, p, num, wtyp, mi, opts)
},
isInit: func(p pointer) error {
- return isInitMessageSliceInfo(p, fi)
+ return isInitMessageSliceInfo(p, mi)
},
}
}
diff --git a/internal/impl/message.go b/internal/impl/message.go
index 5b4beb0..59f04ce 100644
--- a/internal/impl/message.go
+++ b/internal/impl/message.go
@@ -66,26 +66,19 @@
var prefMessageType = reflect.TypeOf((*pref.Message)(nil)).Elem()
-// getMessageInfo returns the MessageInfo (if any) for a type.
-//
-// We find the MessageInfo by calling the ProtoReflect method on the type's
-// zero value and looking at the returned type to see if it is a
-// messageReflectWrapper. Note that the MessageInfo may still be uninitialized
-// at this point.
-func getMessageInfo(mt reflect.Type) (mi *MessageInfo, ok bool) {
- method, ok := mt.MethodByName("ProtoReflect")
+// getMessageInfo returns the MessageInfo for any message type that
+// is generated by our implementation of protoc-gen-go (for v2 and on).
+// If it is unable to obtain a MessageInfo, it returns nil.
+func getMessageInfo(mt reflect.Type) *MessageInfo {
+ m, ok := reflect.Zero(mt).Interface().(pref.ProtoMessage)
if !ok {
- return nil, false
+ return nil
}
- if method.Type.NumIn() != 1 || method.Type.NumOut() != 1 || method.Type.Out(0) != prefMessageType {
- return nil, false
- }
- ret := reflect.Zero(mt).Method(method.Index).Call(nil)
- m, ok := ret[0].Elem().Interface().(*messageReflectWrapper)
+ mr, ok := m.ProtoReflect().(interface{ ProtoMessageInfo() *MessageInfo })
if !ok {
- return nil, ok
+ return nil
}
- return m.mi, true
+ return mr.ProtoMessageInfo()
}
func (mi *MessageInfo) init() {
