vendor.github.com.golang.protobuf.proto.defaults.go Maven / Gradle / Ivy
// Copyright 2019 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
package proto
import (
"google.golang.org/protobuf/reflect/protoreflect"
)
// SetDefaults sets unpopulated scalar fields to their default values.
// Fields within a oneof are not set even if they have a default value.
// SetDefaults is recursively called upon any populated message fields.
func SetDefaults(m Message) {
if m != nil {
setDefaults(MessageReflect(m))
}
}
func setDefaults(m protoreflect.Message) {
fds := m.Descriptor().Fields()
for i := 0; i < fds.Len(); i++ {
fd := fds.Get(i)
if !m.Has(fd) {
if fd.HasDefault() && fd.ContainingOneof() == nil {
v := fd.Default()
if fd.Kind() == protoreflect.BytesKind {
v = protoreflect.ValueOf(append([]byte(nil), v.Bytes()...)) // copy the default bytes
}
m.Set(fd, v)
}
continue
}
}
m.Range(func(fd protoreflect.FieldDescriptor, v protoreflect.Value) bool {
switch {
// Handle singular message.
case fd.Cardinality() != protoreflect.Repeated:
if fd.Message() != nil {
setDefaults(m.Get(fd).Message())
}
// Handle list of messages.
case fd.IsList():
if fd.Message() != nil {
ls := m.Get(fd).List()
for i := 0; i < ls.Len(); i++ {
setDefaults(ls.Get(i).Message())
}
}
// Handle map of messages.
case fd.IsMap():
if fd.MapValue().Message() != nil {
ms := m.Get(fd).Map()
ms.Range(func(_ protoreflect.MapKey, v protoreflect.Value) bool {
setDefaults(v.Message())
return true
})
}
}
return true
})
}