diff options
Diffstat (limited to 'vendor/github.com/golang/protobuf/proto/discard.go')
-rw-r--r-- | vendor/github.com/golang/protobuf/proto/discard.go | 58 |
1 files changed, 58 insertions, 0 deletions
diff --git a/vendor/github.com/golang/protobuf/proto/discard.go b/vendor/github.com/golang/protobuf/proto/discard.go new file mode 100644 index 000000000..2187e877f --- /dev/null +++ b/vendor/github.com/golang/protobuf/proto/discard.go @@ -0,0 +1,58 @@ +// 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" +) + +// DiscardUnknown recursively discards all unknown fields from this message +// and all embedded messages. +// +// When unmarshaling a message with unrecognized fields, the tags and values +// of such fields are preserved in the Message. This allows a later call to +// marshal to be able to produce a message that continues to have those +// unrecognized fields. To avoid this, DiscardUnknown is used to +// explicitly clear the unknown fields after unmarshaling. +func DiscardUnknown(m Message) { + if m != nil { + discardUnknown(MessageReflect(m)) + } +} + +func discardUnknown(m protoreflect.Message) { + m.Range(func(fd protoreflect.FieldDescriptor, val protoreflect.Value) bool { + switch { + // Handle singular message. + case fd.Cardinality() != protoreflect.Repeated: + if fd.Message() != nil { + discardUnknown(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++ { + discardUnknown(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 { + discardUnknown(v.Message()) + return true + }) + } + } + return true + }) + + // Discard unknown fields. + if len(m.GetUnknown()) > 0 { + m.SetUnknown(nil) + } +} |