Use goreleaser to build and release (#244)

Instead of using gox on one side and an action to release, we can merge
them together with goreleaser which will build for extra targets (arm,
mips if needed in the future) and it also takes care of creating
checksums, a source archive, and a changelog and creating a release with
all the artifacts.

All binaries should respect the old naming convention, so any scripts
out there should still work.

Signed-off-by: Itxaka <igarcia@suse.com>

vendor/google.golang.org/protobuf/internal/impl/legacy_message.go

@@ -24,14 +24,24 @@ import (
 // legacyWrapMessage wraps v as a protoreflect.Message,
 // where v must be a *struct kind and not implement the v2 API already.
 func legacyWrapMessage(v reflect.Value) pref.Message {
-	typ := v.Type()
-	if typ.Kind() != reflect.Ptr || typ.Elem().Kind() != reflect.Struct {
+	t := v.Type()
+	if t.Kind() != reflect.Ptr || t.Elem().Kind() != reflect.Struct {
 		return aberrantMessage{v: v}
 	}
-	mt := legacyLoadMessageInfo(typ, "")
+	mt := legacyLoadMessageInfo(t, "")
 	return mt.MessageOf(v.Interface())
 }
 
+// legacyLoadMessageType dynamically loads a protoreflect.Type for t,
+// where t must be not implement the v2 API already.
+// The provided name is used if it cannot be determined from the message.
+func legacyLoadMessageType(t reflect.Type, name pref.FullName) protoreflect.MessageType {
+	if t.Kind() != reflect.Ptr || t.Elem().Kind() != reflect.Struct {
+		return aberrantMessageType{t}
+	}
+	return legacyLoadMessageInfo(t, name)
+}
+
 var legacyMessageTypeCache sync.Map // map[reflect.Type]*MessageInfo
 
 // legacyLoadMessageInfo dynamically loads a *MessageInfo for t,
@@ -49,8 +59,9 @@ func legacyLoadMessageInfo(t reflect.Type, name pref.FullName) *MessageInfo {
 		GoReflectType: t,
 	}
 
+	var hasMarshal, hasUnmarshal bool
 	v := reflect.Zero(t).Interface()
-	if _, ok := v.(legacyMarshaler); ok {
+	if _, hasMarshal = v.(legacyMarshaler); hasMarshal {
 		mi.methods.Marshal = legacyMarshal
 
 		// We have no way to tell whether the type's Marshal method
@@ -59,10 +70,10 @@ func legacyLoadMessageInfo(t reflect.Type, name pref.FullName) *MessageInfo {
 		// calling Marshal methods when present.
 		mi.methods.Flags |= piface.SupportMarshalDeterministic
 	}
-	if _, ok := v.(legacyUnmarshaler); ok {
+	if _, hasUnmarshal = v.(legacyUnmarshaler); hasUnmarshal {
 		mi.methods.Unmarshal = legacyUnmarshal
 	}
-	if _, ok := v.(legacyMerger); ok {
+	if _, hasMerge := v.(legacyMerger); hasMerge || (hasMarshal && hasUnmarshal) {
 		mi.methods.Merge = legacyMerge
 	}
 
@@ -75,7 +86,7 @@ func legacyLoadMessageInfo(t reflect.Type, name pref.FullName) *MessageInfo {
 var legacyMessageDescCache sync.Map // map[reflect.Type]protoreflect.MessageDescriptor
 
 // LegacyLoadMessageDesc returns an MessageDescriptor derived from the Go type,
-// which must be a *struct kind and not implement the v2 API already.
+// which should be a *struct kind and must not implement the v2 API already.
 //
 // This is exported for testing purposes.
 func LegacyLoadMessageDesc(t reflect.Type) pref.MessageDescriptor {
@@ -114,17 +125,19 @@ func legacyLoadMessageDesc(t reflect.Type, name pref.FullName) pref.MessageDescr
 	// If the Go type has no fields, then this might be a proto3 empty message
 	// from before the size cache was added. If there are any fields, check to
 	// see that at least one of them looks like something we generated.
-	if nfield := t.Elem().NumField(); nfield > 0 {
-		hasProtoField := false
-		for i := 0; i < nfield; i++ {
-			f := t.Elem().Field(i)
-			if f.Tag.Get("protobuf") != "" || f.Tag.Get("protobuf_oneof") != "" || strings.HasPrefix(f.Name, "XXX_") {
-				hasProtoField = true
-				break
+	if t.Elem().Kind() == reflect.Struct {
+		if nfield := t.Elem().NumField(); nfield > 0 {
+			hasProtoField := false
+			for i := 0; i < nfield; i++ {
+				f := t.Elem().Field(i)
+				if f.Tag.Get("protobuf") != "" || f.Tag.Get("protobuf_oneof") != "" || strings.HasPrefix(f.Name, "XXX_") {
+					hasProtoField = true
+					break
+				}
+			}
+			if !hasProtoField {
+				return aberrantLoadMessageDesc(t, name)
 			}
-		}
-		if !hasProtoField {
-			return aberrantLoadMessageDesc(t, name)
 		}
 	}
 
@@ -370,7 +383,7 @@ type legacyMerger interface {
 	Merge(protoiface.MessageV1)
 }
 
-var legacyProtoMethods = &piface.Methods{
+var aberrantProtoMethods = &piface.Methods{
 	Marshal:   legacyMarshal,
 	Unmarshal: legacyUnmarshal,
 	Merge:     legacyMerge,
@@ -401,18 +414,47 @@ func legacyUnmarshal(in piface.UnmarshalInput) (piface.UnmarshalOutput, error) {
 	v := in.Message.(unwrapper).protoUnwrap()
 	unmarshaler, ok := v.(legacyUnmarshaler)
 	if !ok {
-		return piface.UnmarshalOutput{}, errors.New("%T does not implement Marshal", v)
+		return piface.UnmarshalOutput{}, errors.New("%T does not implement Unmarshal", v)
 	}
 	return piface.UnmarshalOutput{}, unmarshaler.Unmarshal(in.Buf)
 }
 
 func legacyMerge(in piface.MergeInput) piface.MergeOutput {
+	// Check whether this supports the legacy merger.
 	dstv := in.Destination.(unwrapper).protoUnwrap()
 	merger, ok := dstv.(legacyMerger)
+	if ok {
+		merger.Merge(Export{}.ProtoMessageV1Of(in.Source))
+		return piface.MergeOutput{Flags: piface.MergeComplete}
+	}
+
+	// If legacy merger is unavailable, implement merge in terms of
+	// a marshal and unmarshal operation.
+	srcv := in.Source.(unwrapper).protoUnwrap()
+	marshaler, ok := srcv.(legacyMarshaler)
 	if !ok {
 		return piface.MergeOutput{}
 	}
-	merger.Merge(Export{}.ProtoMessageV1Of(in.Source))
+	dstv = in.Destination.(unwrapper).protoUnwrap()
+	unmarshaler, ok := dstv.(legacyUnmarshaler)
+	if !ok {
+		return piface.MergeOutput{}
+	}
+	if !in.Source.IsValid() {
+		// Legacy Marshal methods may not function on nil messages.
+		// Check for a typed nil source only after we confirm that
+		// legacy Marshal/Unmarshal methods are present, for
+		// consistency.
+		return piface.MergeOutput{Flags: piface.MergeComplete}
+	}
+	b, err := marshaler.Marshal()
+	if err != nil {
+		return piface.MergeOutput{}
+	}
+	err = unmarshaler.Unmarshal(b)
+	if err != nil {
+		return piface.MergeOutput{}
+	}
 	return piface.MergeOutput{Flags: piface.MergeComplete}
 }
 
@@ -422,6 +464,9 @@ type aberrantMessageType struct {
 }
 
 func (mt aberrantMessageType) New() pref.Message {
+	if mt.t.Kind() == reflect.Ptr {
+		return aberrantMessage{reflect.New(mt.t.Elem())}
+	}
 	return aberrantMessage{reflect.Zero(mt.t)}
 }
 func (mt aberrantMessageType) Zero() pref.Message {
@@ -443,6 +488,17 @@ type aberrantMessage struct {
 	v reflect.Value
 }
 
+// Reset implements the v1 proto.Message.Reset method.
+func (m aberrantMessage) Reset() {
+	if mr, ok := m.v.Interface().(interface{ Reset() }); ok {
+		mr.Reset()
+		return
+	}
+	if m.v.Kind() == reflect.Ptr && !m.v.IsNil() {
+		m.v.Elem().Set(reflect.Zero(m.v.Type().Elem()))
+	}
+}
+
 func (m aberrantMessage) ProtoReflect() pref.Message {
 	return m
 }
@@ -454,33 +510,40 @@ func (m aberrantMessage) Type() pref.MessageType {
 	return aberrantMessageType{m.v.Type()}
 }
 func (m aberrantMessage) New() pref.Message {
+	if m.v.Type().Kind() == reflect.Ptr {
+		return aberrantMessage{reflect.New(m.v.Type().Elem())}
+	}
 	return aberrantMessage{reflect.Zero(m.v.Type())}
 }
 func (m aberrantMessage) Interface() pref.ProtoMessage {
 	return m
 }
 func (m aberrantMessage) Range(f func(pref.FieldDescriptor, pref.Value) bool) {
+	return
 }
 func (m aberrantMessage) Has(pref.FieldDescriptor) bool {
-	panic("invalid field descriptor")
+	return false
 }
 func (m aberrantMessage) Clear(pref.FieldDescriptor) {
-	panic("invalid field descriptor")
+	panic("invalid Message.Clear on " + string(m.Descriptor().FullName()))
 }
-func (m aberrantMessage) Get(pref.FieldDescriptor) pref.Value {
-	panic("invalid field descriptor")
+func (m aberrantMessage) Get(fd pref.FieldDescriptor) pref.Value {
+	if fd.Default().IsValid() {
+		return fd.Default()
+	}
+	panic("invalid Message.Get on " + string(m.Descriptor().FullName()))
 }
 func (m aberrantMessage) Set(pref.FieldDescriptor, pref.Value) {
-	panic("invalid field descriptor")
+	panic("invalid Message.Set on " + string(m.Descriptor().FullName()))
 }
 func (m aberrantMessage) Mutable(pref.FieldDescriptor) pref.Value {
-	panic("invalid field descriptor")
+	panic("invalid Message.Mutable on " + string(m.Descriptor().FullName()))
 }
 func (m aberrantMessage) NewField(pref.FieldDescriptor) pref.Value {
-	panic("invalid field descriptor")
+	panic("invalid Message.NewField on " + string(m.Descriptor().FullName()))
 }
 func (m aberrantMessage) WhichOneof(pref.OneofDescriptor) pref.FieldDescriptor {
-	panic("invalid oneof descriptor")
+	panic("invalid Message.WhichOneof descriptor on " + string(m.Descriptor().FullName()))
 }
 func (m aberrantMessage) GetUnknown() pref.RawFields {
 	return nil
@@ -489,13 +552,13 @@ func (m aberrantMessage) SetUnknown(pref.RawFields) {
 	// SetUnknown discards its input on messages which don't support unknown field storage.
 }
 func (m aberrantMessage) IsValid() bool {
-	// An invalid message is a read-only, empty message. Since we don't know anything
-	// about the alleged contents of this message, we can't say with confidence that
-	// it is invalid in this sense. Therefore, report it as valid.
-	return true
+	if m.v.Kind() == reflect.Ptr {
+		return !m.v.IsNil()
+	}
+	return false
 }
 func (m aberrantMessage) ProtoMethods() *piface.Methods {
-	return legacyProtoMethods
+	return aberrantProtoMethods
 }
 func (m aberrantMessage) protoUnwrap() interface{} {
 	return m.v.Interface()