diff --git a/vendor/github.com/jhump/protoreflect/dynamic/dynamic_message.go b/vendor/github.com/jhump/protoreflect/dynamic/dynamic_message.go
new file mode 100644
index 0000000..de13b92
--- /dev/null
+++ b/vendor/github.com/jhump/protoreflect/dynamic/dynamic_message.go
@@ -0,0 +1,2734 @@
+package dynamic
+
+import (
+	"bytes"
+	"compress/gzip"
+	"errors"
+	"fmt"
+	"reflect"
+	"sort"
+	"strings"
+
+	"github.com/golang/protobuf/proto"
+	"github.com/golang/protobuf/protoc-gen-go/descriptor"
+
+	"github.com/jhump/protoreflect/codec"
+	"github.com/jhump/protoreflect/desc"
+	"github.com/jhump/protoreflect/internal"
+)
+
+// ErrUnknownTagNumber is an error that is returned when an operation refers
+// to an unknown tag number.
+var ErrUnknownTagNumber = errors.New("unknown tag number")
+
+// UnknownTagNumberError is the same as ErrUnknownTagNumber.
+// Deprecated: use ErrUnknownTagNumber
+var UnknownTagNumberError = ErrUnknownTagNumber
+
+// ErrUnknownFieldName is an error that is returned when an operation refers
+// to an unknown field name.
+var ErrUnknownFieldName = errors.New("unknown field name")
+
+// UnknownFieldNameError is the same as ErrUnknownFieldName.
+// Deprecated: use ErrUnknownFieldName
+var UnknownFieldNameError = ErrUnknownFieldName
+
+// ErrFieldIsNotMap is an error that is returned when map-related operations
+// are attempted with fields that are not maps.
+var ErrFieldIsNotMap = errors.New("field is not a map type")
+
+// FieldIsNotMapError is the same as ErrFieldIsNotMap.
+// Deprecated: use ErrFieldIsNotMap
+var FieldIsNotMapError = ErrFieldIsNotMap
+
+// ErrFieldIsNotRepeated is an error that is returned when repeated field
+// operations are attempted with fields that are not repeated.
+var ErrFieldIsNotRepeated = errors.New("field is not repeated")
+
+// FieldIsNotRepeatedError is the same as ErrFieldIsNotRepeated.
+// Deprecated: use ErrFieldIsNotRepeated
+var FieldIsNotRepeatedError = ErrFieldIsNotRepeated
+
+// ErrIndexOutOfRange is an error that is returned when an invalid index is
+// provided when access a single element of a repeated field.
+var ErrIndexOutOfRange = errors.New("index is out of range")
+
+// IndexOutOfRangeError is the same as ErrIndexOutOfRange.
+// Deprecated: use ErrIndexOutOfRange
+var IndexOutOfRangeError = ErrIndexOutOfRange
+
+// ErrNumericOverflow is an error returned by operations that encounter a
+// numeric value that is too large, for example de-serializing a value into an
+// int32 field when the value is larger that can fit into a 32-bit value.
+var ErrNumericOverflow = errors.New("numeric value is out of range")
+
+// NumericOverflowError is the same as ErrNumericOverflow.
+// Deprecated: use ErrNumericOverflow
+var NumericOverflowError = ErrNumericOverflow
+
+var typeOfProtoMessage = reflect.TypeOf((*proto.Message)(nil)).Elem()
+var typeOfDynamicMessage = reflect.TypeOf((*Message)(nil))
+var typeOfBytes = reflect.TypeOf(([]byte)(nil))
+
+// Message is a dynamic protobuf message. Instead of a generated struct,
+// like most protobuf messages, this is a map of field number to values and
+// a message descriptor, which is used to validate the field values and
+// also to de-serialize messages (from the standard binary format, as well
+// as from the text format and from JSON).
+type Message struct {
+	md            *desc.MessageDescriptor
+	er            *ExtensionRegistry
+	mf            *MessageFactory
+	extraFields   map[int32]*desc.FieldDescriptor
+	values        map[int32]interface{}
+	unknownFields map[int32][]UnknownField
+}
+
+// UnknownField represents a field that was parsed from the binary wire
+// format for a message, but was not a recognized field number. Enough
+// information is preserved so that re-serializing the message won't lose
+// any of the unrecognized data.
+type UnknownField struct {
+	// Encoding indicates how the unknown field was encoded on the wire. If it
+	// is proto.WireBytes or proto.WireGroupStart then Contents will be set to
+	// the raw bytes. If it is proto.WireTypeFixed32 then the data is in the least
+	// significant 32 bits of Value. Otherwise, the data is in all 64 bits of
+	// Value.
+	Encoding int8
+	Contents []byte
+	Value    uint64
+}
+
+// NewMessage creates a new dynamic message for the type represented by the given
+// message descriptor. During de-serialization, a default MessageFactory is used to
+// instantiate any nested message fields and no extension fields will be parsed. To
+// use a custom MessageFactory or ExtensionRegistry, use MessageFactory.NewMessage.
+func NewMessage(md *desc.MessageDescriptor) *Message {
+	return NewMessageWithMessageFactory(md, nil)
+}
+
+// NewMessageWithExtensionRegistry creates a new dynamic message for the type
+// represented by the given message descriptor. During de-serialization, the given
+// ExtensionRegistry is used to parse extension fields and nested messages will be
+// instantiated using dynamic.NewMessageFactoryWithExtensionRegistry(er).
+func NewMessageWithExtensionRegistry(md *desc.MessageDescriptor, er *ExtensionRegistry) *Message {
+	mf := NewMessageFactoryWithExtensionRegistry(er)
+	return NewMessageWithMessageFactory(md, mf)
+}
+
+// NewMessageWithMessageFactory creates a new dynamic message for the type
+// represented by the given message descriptor. During de-serialization, the given
+// MessageFactory is used to instantiate nested messages.
+func NewMessageWithMessageFactory(md *desc.MessageDescriptor, mf *MessageFactory) *Message {
+	var er *ExtensionRegistry
+	if mf != nil {
+		er = mf.er
+	}
+	return &Message{
+		md: md,
+		mf: mf,
+		er: er,
+	}
+}
+
+// AsDynamicMessage converts the given message to a dynamic message. If the
+// given message is dynamic, it is returned. Otherwise, a dynamic message is
+// created using NewMessage.
+func AsDynamicMessage(msg proto.Message) (*Message, error) {
+	return AsDynamicMessageWithMessageFactory(msg, nil)
+}
+
+// AsDynamicMessageWithExtensionRegistry converts the given message to a dynamic
+// message. If the given message is dynamic, it is returned. Otherwise, a
+// dynamic message is created using NewMessageWithExtensionRegistry.
+func AsDynamicMessageWithExtensionRegistry(msg proto.Message, er *ExtensionRegistry) (*Message, error) {
+	mf := NewMessageFactoryWithExtensionRegistry(er)
+	return AsDynamicMessageWithMessageFactory(msg, mf)
+}
+
+// AsDynamicMessageWithMessageFactory converts the given message to a dynamic
+// message. If the given message is dynamic, it is returned. Otherwise, a
+// dynamic message is created using NewMessageWithMessageFactory.
+func AsDynamicMessageWithMessageFactory(msg proto.Message, mf *MessageFactory) (*Message, error) {
+	if dm, ok := msg.(*Message); ok {
+		return dm, nil
+	}
+	md, err := desc.LoadMessageDescriptorForMessage(msg)
+	if err != nil {
+		return nil, err
+	}
+	dm := NewMessageWithMessageFactory(md, mf)
+	err = dm.mergeFrom(msg)
+	if err != nil {
+		return nil, err
+	}
+	return dm, nil
+}
+
+// GetMessageDescriptor returns a descriptor for this message's type.
+func (m *Message) GetMessageDescriptor() *desc.MessageDescriptor {
+	return m.md
+}
+
+// GetKnownFields returns a slice of descriptors for all known fields. The
+// fields will not be in any defined order.
+func (m *Message) GetKnownFields() []*desc.FieldDescriptor {
+	if len(m.extraFields) == 0 {
+		return m.md.GetFields()
+	}
+	flds := make([]*desc.FieldDescriptor, len(m.md.GetFields()), len(m.md.GetFields())+len(m.extraFields))
+	copy(flds, m.md.GetFields())
+	for _, fld := range m.extraFields {
+		if !fld.IsExtension() {
+			flds = append(flds, fld)
+		}
+	}
+	return flds
+}
+
+// GetKnownExtensions returns a slice of descriptors for all extensions known by
+// the message's extension registry. The fields will not be in any defined order.
+func (m *Message) GetKnownExtensions() []*desc.FieldDescriptor {
+	if !m.md.IsExtendable() {
+		return nil
+	}
+	exts := m.er.AllExtensionsForType(m.md.GetFullyQualifiedName())
+	for _, fld := range m.extraFields {
+		if fld.IsExtension() {
+			exts = append(exts, fld)
+		}
+	}
+	return exts
+}
+
+// GetUnknownFields returns a slice of tag numbers for all unknown fields that
+// this message contains. The tags will not be in any defined order.
+func (m *Message) GetUnknownFields() []int32 {
+	flds := make([]int32, 0, len(m.unknownFields))
+	for tag := range m.unknownFields {
+		flds = append(flds, tag)
+	}
+	return flds
+}
+
+// Descriptor returns the serialized form of the file descriptor in which the
+// message was defined and a path to the message type therein. This mimics the
+// method of the same name on message types generated by protoc.
+func (m *Message) Descriptor() ([]byte, []int) {
+	// get encoded file descriptor
+	b, err := proto.Marshal(m.md.GetFile().AsProto())
+	if err != nil {
+		panic(fmt.Sprintf("failed to get encoded descriptor for %s: %v", m.md.GetFile().GetName(), err))
+	}
+	var zippedBytes bytes.Buffer
+	w := gzip.NewWriter(&zippedBytes)
+	if _, err := w.Write(b); err != nil {
+		panic(fmt.Sprintf("failed to get encoded descriptor for %s: %v", m.md.GetFile().GetName(), err))
+	}
+	if err := w.Close(); err != nil {
+		panic(fmt.Sprintf("failed to get an encoded descriptor for %s: %v", m.md.GetFile().GetName(), err))
+	}
+
+	// and path to message
+	path := []int{}
+	var d desc.Descriptor
+	name := m.md.GetFullyQualifiedName()
+	for d = m.md.GetParent(); d != nil; name, d = d.GetFullyQualifiedName(), d.GetParent() {
+		found := false
+		switch d := d.(type) {
+		case (*desc.FileDescriptor):
+			for i, md := range d.GetMessageTypes() {
+				if md.GetFullyQualifiedName() == name {
+					found = true
+					path = append(path, i)
+				}
+			}
+		case (*desc.MessageDescriptor):
+			for i, md := range d.GetNestedMessageTypes() {
+				if md.GetFullyQualifiedName() == name {
+					found = true
+					path = append(path, i)
+				}
+			}
+		}
+		if !found {
+			panic(fmt.Sprintf("failed to compute descriptor path for %s", m.md.GetFullyQualifiedName()))
+		}
+	}
+	// reverse the path
+	i := 0
+	j := len(path) - 1
+	for i < j {
+		path[i], path[j] = path[j], path[i]
+		i++
+		j--
+	}
+
+	return zippedBytes.Bytes(), path
+}
+
+// XXX_MessageName returns the fully qualified name of this message's type. This
+// allows dynamic messages to be used with proto.MessageName.
+func (m *Message) XXX_MessageName() string {
+	return m.md.GetFullyQualifiedName()
+}
+
+// FindFieldDescriptor returns a field descriptor for the given tag number. This
+// searches known fields in the descriptor, known fields discovered during calls
+// to GetField or SetField, and extension fields known by the message's extension
+// registry. It returns nil if the tag is unknown.
+func (m *Message) FindFieldDescriptor(tagNumber int32) *desc.FieldDescriptor {
+	fd := m.md.FindFieldByNumber(tagNumber)
+	if fd != nil {
+		return fd
+	}
+	fd = m.er.FindExtension(m.md.GetFullyQualifiedName(), tagNumber)
+	if fd != nil {
+		return fd
+	}
+	return m.extraFields[tagNumber]
+}
+
+// FindFieldDescriptorByName returns a field descriptor for the given field
+// name. This searches known fields in the descriptor, known fields discovered
+// during calls to GetField or SetField, and extension fields known by the
+// message's extension registry. It returns nil if the name is unknown. If the
+// given name refers to an extension, it should be fully qualified and may be
+// optionally enclosed in parentheses or brackets.
+func (m *Message) FindFieldDescriptorByName(name string) *desc.FieldDescriptor {
+	if name == "" {
+		return nil
+	}
+	fd := m.md.FindFieldByName(name)
+	if fd != nil {
+		return fd
+	}
+	mustBeExt := false
+	if name[0] == '(' {
+		if name[len(name)-1] != ')' {
+			// malformed name
+			return nil
+		}
+		mustBeExt = true
+		name = name[1 : len(name)-1]
+	} else if name[0] == '[' {
+		if name[len(name)-1] != ']' {
+			// malformed name
+			return nil
+		}
+		mustBeExt = true
+		name = name[1 : len(name)-1]
+	}
+	fd = m.er.FindExtensionByName(m.md.GetFullyQualifiedName(), name)
+	if fd != nil {
+		return fd
+	}
+	for _, fd := range m.extraFields {
+		if fd.IsExtension() && name == fd.GetFullyQualifiedName() {
+			return fd
+		} else if !mustBeExt && !fd.IsExtension() && name == fd.GetName() {
+			return fd
+		}
+	}
+
+	return nil
+}
+
+// FindFieldDescriptorByJSONName returns a field descriptor for the given JSON
+// name. This searches known fields in the descriptor, known fields discovered
+// during calls to GetField or SetField, and extension fields known by the
+// message's extension registry. If no field matches the given JSON name, it
+// will fall back to searching field names (e.g. FindFieldDescriptorByName). If
+// this also yields no match, nil is returned.
+func (m *Message) FindFieldDescriptorByJSONName(name string) *desc.FieldDescriptor {
+	if name == "" {
+		return nil
+	}
+	fd := m.md.FindFieldByJSONName(name)
+	if fd != nil {
+		return fd
+	}
+	mustBeExt := false
+	if name[0] == '(' {
+		if name[len(name)-1] != ')' {
+			// malformed name
+			return nil
+		}
+		mustBeExt = true
+		name = name[1 : len(name)-1]
+	} else if name[0] == '[' {
+		if name[len(name)-1] != ']' {
+			// malformed name
+			return nil
+		}
+		mustBeExt = true
+		name = name[1 : len(name)-1]
+	}
+	fd = m.er.FindExtensionByJSONName(m.md.GetFullyQualifiedName(), name)
+	if fd != nil {
+		return fd
+	}
+	for _, fd := range m.extraFields {
+		if fd.IsExtension() && name == fd.GetFullyQualifiedJSONName() {
+			return fd
+		} else if !mustBeExt && !fd.IsExtension() && name == fd.GetJSONName() {
+			return fd
+		}
+	}
+
+	// try non-JSON names
+	return m.FindFieldDescriptorByName(name)
+}
+
+func (m *Message) checkField(fd *desc.FieldDescriptor) error {
+	return checkField(fd, m.md)
+}
+
+func checkField(fd *desc.FieldDescriptor, md *desc.MessageDescriptor) error {
+	if fd.GetOwner().GetFullyQualifiedName() != md.GetFullyQualifiedName() {
+		return fmt.Errorf("given field, %s, is for wrong message type: %s; expecting %s", fd.GetName(), fd.GetOwner().GetFullyQualifiedName(), md.GetFullyQualifiedName())
+	}
+	if fd.IsExtension() && !md.IsExtension(fd.GetNumber()) {
+		return fmt.Errorf("given field, %s, is an extension but is not in message extension range: %v", fd.GetFullyQualifiedName(), md.GetExtensionRanges())
+	}
+	return nil
+}
+
+// GetField returns the value for the given field descriptor. It panics if an
+// error is encountered. See TryGetField.
+func (m *Message) GetField(fd *desc.FieldDescriptor) interface{} {
+	if v, err := m.TryGetField(fd); err != nil {
+		panic(err.Error())
+	} else {
+		return v
+	}
+}
+
+// TryGetField returns the value for the given field descriptor. An error is
+// returned if the given field descriptor does not belong to the right message
+// type.
+//
+// The Go type of the returned value, for scalar fields, is the same as protoc
+// would generate for the field (in a non-dynamic message). The table below
+// lists the scalar types and the corresponding Go types.
+//  +-------------------------+-----------+
+//  |       Declared Type     |  Go Type  |
+//  +-------------------------+-----------+
+//  | int32, sint32, sfixed32 | int32     |
+//  | int64, sint64, sfixed64 | int64     |
+//  | uint32, fixed32         | uint32    |
+//  | uint64, fixed64         | uint64    |
+//  | float                   | float32   |
+//  | double                  | double32  |
+//  | bool                    | bool      |
+//  | string                  | string    |
+//  | bytes                   | []byte    |
+//  +-------------------------+-----------+
+//
+// Values for enum fields will always be int32 values. You can use the enum
+// descriptor associated with the field to lookup value names with those values.
+// Values for message type fields may be an instance of the generated type *or*
+// may be another *dynamic.Message that represents the type.
+//
+// If the given field is a map field, the returned type will be
+// map[interface{}]interface{}. The actual concrete types of keys and values is
+// as described above. If the given field is a (non-map) repeated field, the
+// returned type is always []interface{}; the type of the actual elements is as
+// described above.
+//
+// If this message has no value for the given field, its default value is
+// returned. If the message is defined in a file with "proto3" syntax, the
+// default is always the zero value for the field. The default value for map and
+// repeated fields is a nil map or slice (respectively). For field's whose types
+// is a message, the default value is an empty message for "proto2" syntax or a
+// nil message for "proto3" syntax. Note that the in the latter case, a non-nil
+// interface with a nil pointer is returned, not a nil interface. Also note that
+// whether the returned value is an empty message or nil depends on if *this*
+// message was defined as "proto3" syntax, not the message type referred to by
+// the field's type.
+//
+// If the given field descriptor is not known (e.g. not present in the message
+// descriptor) but corresponds to an unknown field, the unknown value will be
+// parsed and become known. The parsed value will be returned, or an error will
+// be returned if the unknown value cannot be parsed according to the field
+// descriptor's type information.
+func (m *Message) TryGetField(fd *desc.FieldDescriptor) (interface{}, error) {
+	if err := m.checkField(fd); err != nil {
+		return nil, err
+	}
+	return m.getField(fd)
+}
+
+// GetFieldByName returns the value for the field with the given name. It panics
+// if an error is encountered. See TryGetFieldByName.
+func (m *Message) GetFieldByName(name string) interface{} {
+	if v, err := m.TryGetFieldByName(name); err != nil {
+		panic(err.Error())
+	} else {
+		return v
+	}
+}
+
+// TryGetFieldByName returns the value for the field with the given name. An
+// error is returned if the given name is unknown. If the given name refers to
+// an extension field, it should be fully qualified and optionally enclosed in
+// parenthesis or brackets.
+//
+// If this message has no value for the given field, its default value is
+// returned. (See TryGetField for more info on types and default field values.)
+func (m *Message) TryGetFieldByName(name string) (interface{}, error) {
+	fd := m.FindFieldDescriptorByName(name)
+	if fd == nil {
+		return nil, UnknownFieldNameError
+	}
+	return m.getField(fd)
+}
+
+// GetFieldByNumber returns the value for the field with the given tag number.
+// It panics if an error is encountered. See TryGetFieldByNumber.
+func (m *Message) GetFieldByNumber(tagNumber int) interface{} {
+	if v, err := m.TryGetFieldByNumber(tagNumber); err != nil {
+		panic(err.Error())
+	} else {
+		return v
+	}
+}
+
+// TryGetFieldByNumber returns the value for the field with the given tag
+// number. An error is returned if the given tag is unknown.
+//
+// If this message has no value for the given field, its default value is
+// returned. (See TryGetField for more info on types and default field values.)
+func (m *Message) TryGetFieldByNumber(tagNumber int) (interface{}, error) {
+	fd := m.FindFieldDescriptor(int32(tagNumber))
+	if fd == nil {
+		return nil, UnknownTagNumberError
+	}
+	return m.getField(fd)
+}
+
+func (m *Message) getField(fd *desc.FieldDescriptor) (interface{}, error) {
+	return m.doGetField(fd, false)
+}
+
+func (m *Message) doGetField(fd *desc.FieldDescriptor, nilIfAbsent bool) (interface{}, error) {
+	res := m.values[fd.GetNumber()]
+	if res == nil {
+		var err error
+		if res, err = m.parseUnknownField(fd); err != nil {
+			return nil, err
+		}
+		if res == nil {
+			if nilIfAbsent {
+				return nil, nil
+			} else {
+				def := fd.GetDefaultValue()
+				if def != nil {
+					return def, nil
+				}
+				// GetDefaultValue only returns nil for message types
+				md := fd.GetMessageType()
+				if m.md.IsProto3() {
+					return nilMessage(md), nil
+				} else {
+					// for proto2, return default instance of message
+					return m.mf.NewMessage(md), nil
+				}
+			}
+		}
+	}
+	rt := reflect.TypeOf(res)
+	if rt.Kind() == reflect.Map {
+		// make defensive copies to prevent caller from storing illegal keys and values
+		m := res.(map[interface{}]interface{})
+		res := map[interface{}]interface{}{}
+		for k, v := range m {
+			res[k] = v
+		}
+		return res, nil
+	} else if rt.Kind() == reflect.Slice && rt != typeOfBytes {
+		// make defensive copies to prevent caller from storing illegal elements
+		sl := res.([]interface{})
+		res := make([]interface{}, len(sl))
+		copy(res, sl)
+		return res, nil
+	}
+	return res, nil
+}
+
+func nilMessage(md *desc.MessageDescriptor) interface{} {
+	// try to return a proper nil pointer
+	msgType := proto.MessageType(md.GetFullyQualifiedName())
+	if msgType != nil && msgType.Implements(typeOfProtoMessage) {
+		return reflect.Zero(msgType).Interface().(proto.Message)
+	}
+	// fallback to nil dynamic message pointer
+	return (*Message)(nil)
+}
+
+// HasField returns true if this message has a value for the given field. If the
+// given field is not valid (e.g. belongs to a different message type), false is
+// returned. If this message is defined in a file with "proto3" syntax, this
+// will return false even if a field was explicitly assigned its zero value (the
+// zero values for a field are intentionally indistinguishable from absent).
+func (m *Message) HasField(fd *desc.FieldDescriptor) bool {
+	if err := m.checkField(fd); err != nil {
+		return false
+	}
+	return m.HasFieldNumber(int(fd.GetNumber()))
+}
+
+// HasFieldName returns true if this message has a value for a field with the
+// given name. If the given name is unknown, this returns false.
+func (m *Message) HasFieldName(name string) bool {
+	fd := m.FindFieldDescriptorByName(name)
+	if fd == nil {
+		return false
+	}
+	return m.HasFieldNumber(int(fd.GetNumber()))
+}
+
+// HasFieldNumber returns true if this message has a value for a field with the
+// given tag number. If the given tag is unknown, this returns false.
+func (m *Message) HasFieldNumber(tagNumber int) bool {
+	if _, ok := m.values[int32(tagNumber)]; ok {
+		return true
+	}
+	_, ok := m.unknownFields[int32(tagNumber)]
+	return ok
+}
+
+// SetField sets the value for the given field descriptor to the given value. It
+// panics if an error is encountered. See TrySetField.
+func (m *Message) SetField(fd *desc.FieldDescriptor, val interface{}) {
+	if err := m.TrySetField(fd, val); err != nil {
+		panic(err.Error())
+	}
+}
+
+// TrySetField sets the value for the given field descriptor to the given value.
+// An error is returned if the given field descriptor does not belong to the
+// right message type or if the given value is not a correct/compatible type for
+// the given field.
+//
+// The Go type expected for a field  is the same as TryGetField would return for
+// the field. So message values can be supplied as either the correct generated
+// message type or as a *dynamic.Message.
+//
+// Since it is cumbersome to work with dynamic messages, some concessions are
+// made to simplify usage regarding types:
+//
+//  1. If a numeric type is provided that can be converted *without loss or
+//     overflow*, it is accepted. This allows for setting int64 fields using int
+//     or int32 values. Similarly for uint64 with uint and uint32 values and for
+//     float64 fields with float32 values.
+//  2. The value can be a named type, as long as its underlying type is correct.
+//  3. Map and repeated fields can be set using any kind of concrete map or
+//     slice type, as long as the values within are all of the correct type. So
+//     a field defined as a 'map<string, int32>` can be set using a
+//     map[string]int32, a map[string]interface{}, or even a
+//     map[interface{}]interface{}.
+//  4. Finally, dynamic code that chooses to not treat maps as a special-case
+//     find that they can set map fields using a slice where each element is a
+//     message that matches the implicit map-entry field message type.
+//
+// If the given field descriptor is not known (e.g. not present in the message
+// descriptor) it will become known. Subsequent operations using tag numbers or
+// names will be able to resolve the newly-known type. If the message has a
+// value for the unknown value, it is cleared, replaced by the given known
+// value.
+func (m *Message) TrySetField(fd *desc.FieldDescriptor, val interface{}) error {
+	if err := m.checkField(fd); err != nil {
+		return err
+	}
+	return m.setField(fd, val)
+}
+
+// SetFieldByName sets the value for the field with the given name to the given
+// value. It panics if an error is encountered. See TrySetFieldByName.
+func (m *Message) SetFieldByName(name string, val interface{}) {
+	if err := m.TrySetFieldByName(name, val); err != nil {
+		panic(err.Error())
+	}
+}
+
+// TrySetFieldByName sets the value for the field with the given name to the
+// given value. An error is returned if the given name is unknown or if the
+// given value has an incorrect type. If the given name refers to an extension
+// field, it should be fully qualified and optionally enclosed in parenthesis or
+// brackets.
+//
+// (See TrySetField for more info on types.)
+func (m *Message) TrySetFieldByName(name string, val interface{}) error {
+	fd := m.FindFieldDescriptorByName(name)
+	if fd == nil {
+		return UnknownFieldNameError
+	}
+	return m.setField(fd, val)
+}
+
+// SetFieldByNumber sets the value for the field with the given tag number to
+// the given value. It panics if an error is encountered. See
+// TrySetFieldByNumber.
+func (m *Message) SetFieldByNumber(tagNumber int, val interface{}) {
+	if err := m.TrySetFieldByNumber(tagNumber, val); err != nil {
+		panic(err.Error())
+	}
+}
+
+// TrySetFieldByNumber sets the value for the field with the given tag number to
+// the given value. An error is returned if the given tag is unknown or if the
+// given value has an incorrect type.
+//
+// (See TrySetField for more info on types.)
+func (m *Message) TrySetFieldByNumber(tagNumber int, val interface{}) error {
+	fd := m.FindFieldDescriptor(int32(tagNumber))
+	if fd == nil {
+		return UnknownTagNumberError
+	}
+	return m.setField(fd, val)
+}
+
+func (m *Message) setField(fd *desc.FieldDescriptor, val interface{}) error {
+	var err error
+	if val, err = validFieldValue(fd, val); err != nil {
+		return err
+	}
+	m.internalSetField(fd, val)
+	return nil
+}
+
+func (m *Message) internalSetField(fd *desc.FieldDescriptor, val interface{}) {
+	if fd.IsRepeated() {
+		// Unset fields and zero-length fields are indistinguishable, in both
+		// proto2 and proto3 syntax
+		if reflect.ValueOf(val).Len() == 0 {
+			if m.values != nil {
+				delete(m.values, fd.GetNumber())
+			}
+			return
+		}
+	} else if m.md.IsProto3() && fd.GetOneOf() == nil {
+		// proto3 considers fields that are set to their zero value as unset
+		// (we already handled repeated fields above)
+		var equal bool
+		if b, ok := val.([]byte); ok {
+			// can't compare slices, so we have to special-case []byte values
+			equal = ok && bytes.Equal(b, fd.GetDefaultValue().([]byte))
+		} else {
+			defVal := fd.GetDefaultValue()
+			equal = defVal == val
+			if !equal && defVal == nil {
+				// above just checks if value is the nil interface,
+				// but we should also test if the given value is a
+				// nil pointer
+				rv := reflect.ValueOf(val)
+				if rv.Kind() == reflect.Ptr && rv.IsNil() {
+					equal = true
+				}
+			}
+		}
+		if equal {
+			if m.values != nil {
+				delete(m.values, fd.GetNumber())
+			}
+			return
+		}
+	}
+	if m.values == nil {
+		m.values = map[int32]interface{}{}
+	}
+	m.values[fd.GetNumber()] = val
+	// if this field is part of a one-of, make sure all other one-of choices are cleared
+	od := fd.GetOneOf()
+	if od != nil {
+		for _, other := range od.GetChoices() {
+			if other.GetNumber() != fd.GetNumber() {
+				delete(m.values, other.GetNumber())
+			}
+		}
+	}
+	// also clear any unknown fields
+	if m.unknownFields != nil {
+		delete(m.unknownFields, fd.GetNumber())
+	}
+	// and add this field if it was previously unknown
+	if existing := m.FindFieldDescriptor(fd.GetNumber()); existing == nil {
+		m.addField(fd)
+	}
+}
+
+func (m *Message) addField(fd *desc.FieldDescriptor) {
+	if m.extraFields == nil {
+		m.extraFields = map[int32]*desc.FieldDescriptor{}
+	}
+	m.extraFields[fd.GetNumber()] = fd
+}
+
+// ClearField removes any value for the given field. It panics if an error is
+// encountered. See TryClearField.
+func (m *Message) ClearField(fd *desc.FieldDescriptor) {
+	if err := m.TryClearField(fd); err != nil {
+		panic(err.Error())
+	}
+}
+
+// TryClearField removes any value for the given field. An error is returned if
+// the given field descriptor does not belong to the right message type.
+func (m *Message) TryClearField(fd *desc.FieldDescriptor) error {
+	if err := m.checkField(fd); err != nil {
+		return err
+	}
+	m.clearField(fd)
+	return nil
+}
+
+// ClearFieldByName removes any value for the field with the given name. It
+// panics if an error is encountered. See TryClearFieldByName.
+func (m *Message) ClearFieldByName(name string) {
+	if err := m.TryClearFieldByName(name); err != nil {
+		panic(err.Error())
+	}
+}
+
+// TryClearFieldByName removes any value for the field with the given name. An
+// error is returned if the given name is unknown. If the given name refers to
+// an extension field, it should be fully qualified and optionally enclosed in
+// parenthesis or brackets.
+func (m *Message) TryClearFieldByName(name string) error {
+	fd := m.FindFieldDescriptorByName(name)
+	if fd == nil {
+		return UnknownFieldNameError
+	}
+	m.clearField(fd)
+	return nil
+}
+
+// ClearFieldByNumber removes any value for the field with the given tag number.
+// It panics if an error is encountered. See TryClearFieldByNumber.
+func (m *Message) ClearFieldByNumber(tagNumber int) {
+	if err := m.TryClearFieldByNumber(tagNumber); err != nil {
+		panic(err.Error())
+	}
+}
+
+// TryClearFieldByNumber removes any value for the field with the given tag
+// number. An error is returned if the given tag is unknown.
+func (m *Message) TryClearFieldByNumber(tagNumber int) error {
+	fd := m.FindFieldDescriptor(int32(tagNumber))
+	if fd == nil {
+		return UnknownTagNumberError
+	}
+	m.clearField(fd)
+	return nil
+}
+
+func (m *Message) clearField(fd *desc.FieldDescriptor) {
+	// clear value
+	if m.values != nil {
+		delete(m.values, fd.GetNumber())
+	}
+	// also clear any unknown fields
+	if m.unknownFields != nil {
+		delete(m.unknownFields, fd.GetNumber())
+	}
+	// and add this field if it was previously unknown
+	if existing := m.FindFieldDescriptor(fd.GetNumber()); existing == nil {
+		m.addField(fd)
+	}
+}
+
+// GetOneOfField returns which of the given one-of's fields is set and the
+// corresponding value. It panics if an error is encountered. See
+// TryGetOneOfField.
+func (m *Message) GetOneOfField(od *desc.OneOfDescriptor) (*desc.FieldDescriptor, interface{}) {
+	if fd, val, err := m.TryGetOneOfField(od); err != nil {
+		panic(err.Error())
+	} else {
+		return fd, val
+	}
+}
+
+// TryGetOneOfField returns which of the given one-of's fields is set and the
+// corresponding value. An error is returned if the given one-of belongs to the
+// wrong message type. If the given one-of has no field set, this method will
+// return nil, nil.
+//
+// The type of the value, if one is set, is the same as would be returned by
+// TryGetField using the returned field descriptor.
+//
+// Like with TryGetField, if the given one-of contains any fields that are not
+// known (e.g. not present in this message's descriptor), they will become known
+// and any unknown value will be parsed (and become a known value on success).
+func (m *Message) TryGetOneOfField(od *desc.OneOfDescriptor) (*desc.FieldDescriptor, interface{}, error) {
+	if od.GetOwner().GetFullyQualifiedName() != m.md.GetFullyQualifiedName() {
+		return nil, nil, fmt.Errorf("given one-of, %s, is for wrong message type: %s; expecting %s", od.GetName(), od.GetOwner().GetFullyQualifiedName(), m.md.GetFullyQualifiedName())
+	}
+	for _, fd := range od.GetChoices() {
+		val, err := m.doGetField(fd, true)
+		if err != nil {
+			return nil, nil, err
+		}
+		if val != nil {
+			return fd, val, nil
+		}
+	}
+	return nil, nil, nil
+}
+
+// ClearOneOfField removes any value for any of the given one-of's fields. It
+// panics if an error is encountered. See TryClearOneOfField.
+func (m *Message) ClearOneOfField(od *desc.OneOfDescriptor) {
+	if err := m.TryClearOneOfField(od); err != nil {
+		panic(err.Error())
+	}
+}
+
+// TryClearOneOfField removes any value for any of the given one-of's fields. An
+// error is returned if the given one-of descriptor does not belong to the right
+// message type.
+func (m *Message) TryClearOneOfField(od *desc.OneOfDescriptor) error {
+	if od.GetOwner().GetFullyQualifiedName() != m.md.GetFullyQualifiedName() {
+		return fmt.Errorf("given one-of, %s, is for wrong message type: %s; expecting %s", od.GetName(), od.GetOwner().GetFullyQualifiedName(), m.md.GetFullyQualifiedName())
+	}
+	for _, fd := range od.GetChoices() {
+		m.clearField(fd)
+	}
+	return nil
+}
+
+// GetMapField returns the value for the given map field descriptor and given
+// key. It panics if an error is encountered. See TryGetMapField.
+func (m *Message) GetMapField(fd *desc.FieldDescriptor, key interface{}) interface{} {
+	if v, err := m.TryGetMapField(fd, key); err != nil {
+		panic(err.Error())
+	} else {
+		return v
+	}
+}
+
+// TryGetMapField returns the value for the given map field descriptor and given
+// key. An error is returned if the given field descriptor does not belong to
+// the right message type or if it is not a map field.
+//
+// If the map field does not contain the requested key, this method returns
+// nil, nil. The Go type of the value returned mirrors the type that protoc
+// would generate for the field. (See TryGetField for more details on types).
+//
+// If the given field descriptor is not known (e.g. not present in the message
+// descriptor) but corresponds to an unknown field, the unknown value will be
+// parsed and become known. The parsed value will be searched for the requested
+// key and any value returned. An error will be returned if the unknown value
+// cannot be parsed according to the field descriptor's type information.
+func (m *Message) TryGetMapField(fd *desc.FieldDescriptor, key interface{}) (interface{}, error) {
+	if err := m.checkField(fd); err != nil {
+		return nil, err
+	}
+	return m.getMapField(fd, key)
+}
+
+// GetMapFieldByName returns the value for the map field with the given name and
+// given key. It panics if an error is encountered. See TryGetMapFieldByName.
+func (m *Message) GetMapFieldByName(name string, key interface{}) interface{} {
+	if v, err := m.TryGetMapFieldByName(name, key); err != nil {
+		panic(err.Error())
+	} else {
+		return v
+	}
+}
+
+// TryGetMapFieldByName returns the value for the map field with the given name
+// and given key. An error is returned if the given name is unknown or if it
+// names a field that is not a map field.
+//
+// If this message has no value for the given field or the value has no value
+// for the requested key, then this method returns nil, nil.
+//
+// (See TryGetField for more info on types.)
+func (m *Message) TryGetMapFieldByName(name string, key interface{}) (interface{}, error) {
+	fd := m.FindFieldDescriptorByName(name)
+	if fd == nil {
+		return nil, UnknownFieldNameError
+	}
+	return m.getMapField(fd, key)
+}
+
+// GetMapFieldByNumber returns the value for the map field with the given tag
+// number and given key. It panics if an error is encountered. See
+// TryGetMapFieldByNumber.
+func (m *Message) GetMapFieldByNumber(tagNumber int, key interface{}) interface{} {
+	if v, err := m.TryGetMapFieldByNumber(tagNumber, key); err != nil {
+		panic(err.Error())
+	} else {
+		return v
+	}
+}
+
+// TryGetMapFieldByNumber returns the value for the map field with the given tag
+// number and given key. An error is returned if the given tag is unknown or if
+// it indicates a field that is not a map field.
+//
+// If this message has no value for the given field or the value has no value
+// for the requested key, then this method returns nil, nil.
+//
+// (See TryGetField for more info on types.)
+func (m *Message) TryGetMapFieldByNumber(tagNumber int, key interface{}) (interface{}, error) {
+	fd := m.FindFieldDescriptor(int32(tagNumber))
+	if fd == nil {
+		return nil, UnknownTagNumberError
+	}
+	return m.getMapField(fd, key)
+}
+
+func (m *Message) getMapField(fd *desc.FieldDescriptor, key interface{}) (interface{}, error) {
+	if !fd.IsMap() {
+		return nil, FieldIsNotMapError
+	}
+	kfd := fd.GetMessageType().GetFields()[0]
+	ki, err := validElementFieldValue(kfd, key, false)
+	if err != nil {
+		return nil, err
+	}
+	mp := m.values[fd.GetNumber()]
+	if mp == nil {
+		if mp, err = m.parseUnknownField(fd); err != nil {
+			return nil, err
+		} else if mp == nil {
+			return nil, nil
+		}
+	}
+	return mp.(map[interface{}]interface{})[ki], nil
+}
+
+// ForEachMapFieldEntry executes the given function for each entry in the map
+// value for the given field descriptor. It stops iteration if the function
+// returns false. It panics if an error is encountered. See
+// TryForEachMapFieldEntry.
+func (m *Message) ForEachMapFieldEntry(fd *desc.FieldDescriptor, fn func(key, val interface{}) bool) {
+	if err := m.TryForEachMapFieldEntry(fd, fn); err != nil {
+		panic(err.Error())
+	}
+}
+
+// TryForEachMapFieldEntry executes the given function for each entry in the map
+// value for the given field descriptor. An error is returned if the given field
+// descriptor does not belong to the right message type or if it is not a  map
+// field.
+//
+// Iteration ends either when all entries have been examined or when the given
+// function returns false. So the function is expected to return true for normal
+// iteration and false to break out. If this message has no value for the given
+// field, it returns without invoking the given function.
+//
+// The Go type of the key and value supplied to the function mirrors the type
+// that protoc would generate for the field. (See TryGetField for more details
+// on types).
+//
+// If the given field descriptor is not known (e.g. not present in the message
+// descriptor) but corresponds to an unknown field, the unknown value will be
+// parsed and become known. The parsed value will be searched for the requested
+// key and any value returned. An error will be returned if the unknown value
+// cannot be parsed according to the field descriptor's type information.
+func (m *Message) TryForEachMapFieldEntry(fd *desc.FieldDescriptor, fn func(key, val interface{}) bool) error {
+	if err := m.checkField(fd); err != nil {
+		return err
+	}
+	return m.forEachMapFieldEntry(fd, fn)
+}
+
+// ForEachMapFieldEntryByName executes the given function for each entry in the
+// map value for the field with the given name. It stops iteration if the
+// function returns false. It panics if an error is encountered. See
+// TryForEachMapFieldEntryByName.
+func (m *Message) ForEachMapFieldEntryByName(name string, fn func(key, val interface{}) bool) {
+	if err := m.TryForEachMapFieldEntryByName(name, fn); err != nil {
+		panic(err.Error())
+	}
+}
+
+// TryForEachMapFieldEntryByName executes the given function for each entry in
+// the map value for the field with the given name. It stops iteration if the
+// function returns false. An error is returned if the given name is unknown or
+// if it names a field that is not a map field.
+//
+// If this message has no value for the given field, it returns without ever
+// invoking the given function.
+//
+// (See TryGetField for more info on types supplied to the function.)
+func (m *Message) TryForEachMapFieldEntryByName(name string, fn func(key, val interface{}) bool) error {
+	fd := m.FindFieldDescriptorByName(name)
+	if fd == nil {
+		return UnknownFieldNameError
+	}
+	return m.forEachMapFieldEntry(fd, fn)
+}
+
+// ForEachMapFieldEntryByNumber executes the given function for each entry in
+// the map value for the field with the given tag number. It stops iteration if
+// the function returns false. It panics if an error is encountered. See
+// TryForEachMapFieldEntryByNumber.
+func (m *Message) ForEachMapFieldEntryByNumber(tagNumber int, fn func(key, val interface{}) bool) {
+	if err := m.TryForEachMapFieldEntryByNumber(tagNumber, fn); err != nil {
+		panic(err.Error())
+	}
+}
+
+// TryForEachMapFieldEntryByNumber executes the given function for each entry in
+// the map value for the field with the given tag number. It stops iteration if
+// the function returns false. An error is returned if the given tag is unknown
+// or if it indicates a field that is not a map field.
+//
+// If this message has no value for the given field, it returns without ever
+// invoking the given function.
+//
+// (See TryGetField for more info on types supplied to the function.)
+func (m *Message) TryForEachMapFieldEntryByNumber(tagNumber int, fn func(key, val interface{}) bool) error {
+	fd := m.FindFieldDescriptor(int32(tagNumber))
+	if fd == nil {
+		return UnknownTagNumberError
+	}
+	return m.forEachMapFieldEntry(fd, fn)
+}
+
+func (m *Message) forEachMapFieldEntry(fd *desc.FieldDescriptor, fn func(key, val interface{}) bool) error {
+	if !fd.IsMap() {
+		return FieldIsNotMapError
+	}
+	mp := m.values[fd.GetNumber()]
+	if mp == nil {
+		if mp, err := m.parseUnknownField(fd); err != nil {
+			return err
+		} else if mp == nil {
+			return nil
+		}
+	}
+	for k, v := range mp.(map[interface{}]interface{}) {
+		if !fn(k, v) {
+			break
+		}
+	}
+	return nil
+}
+
+// PutMapField sets the value for the given map field descriptor and given key
+// to the given value. It panics if an error is encountered. See TryPutMapField.
+func (m *Message) PutMapField(fd *desc.FieldDescriptor, key interface{}, val interface{}) {
+	if err := m.TryPutMapField(fd, key, val); err != nil {
+		panic(err.Error())
+	}
+}
+
+// TryPutMapField sets the value for the given map field descriptor and given
+// key to the given value. An error is returned if the given field descriptor
+// does not belong to the right message type, if the given field is not a map
+// field, or if the given value is not a correct/compatible type for the given
+// field.
+//
+// The Go type expected for a field  is the same as required by TrySetField for
+// a field with the same type as the map's value type.
+//
+// If the given field descriptor is not known (e.g. not present in the message
+// descriptor) it will become known. Subsequent operations using tag numbers or
+// names will be able to resolve the newly-known type. If the message has a
+// value for the unknown value, it is cleared, replaced by the given known
+// value.
+func (m *Message) TryPutMapField(fd *desc.FieldDescriptor, key interface{}, val interface{}) error {
+	if err := m.checkField(fd); err != nil {
+		return err
+	}
+	return m.putMapField(fd, key, val)
+}
+
+// PutMapFieldByName sets the value for the map field with the given name and
+// given key to the given value. It panics if an error is encountered. See
+// TryPutMapFieldByName.
+func (m *Message) PutMapFieldByName(name string, key interface{}, val interface{}) {
+	if err := m.TryPutMapFieldByName(name, key, val); err != nil {
+		panic(err.Error())
+	}
+}
+
+// TryPutMapFieldByName sets the value for the map field with the given name and
+// the given key to the given value. An error is returned if the given name is
+// unknown, if it names a field that is not a map, or if the given value has an
+// incorrect type.
+//
+// (See TrySetField for more info on types.)
+func (m *Message) TryPutMapFieldByName(name string, key interface{}, val interface{}) error {
+	fd := m.FindFieldDescriptorByName(name)
+	if fd == nil {
+		return UnknownFieldNameError
+	}
+	return m.putMapField(fd, key, val)
+}
+
+// PutMapFieldByNumber sets the value for the map field with the given tag
+// number and given key to the given value. It panics if an error is
+// encountered. See TryPutMapFieldByNumber.
+func (m *Message) PutMapFieldByNumber(tagNumber int, key interface{}, val interface{}) {
+	if err := m.TryPutMapFieldByNumber(tagNumber, key, val); err != nil {
+		panic(err.Error())
+	}
+}
+
+// TryPutMapFieldByNumber sets the value for the map field with the given tag
+// number and the given key to the given value. An error is returned if the
+// given tag is unknown, if it indicates a field that is not a map, or if the
+// given value has an incorrect type.
+//
+// (See TrySetField for more info on types.)
+func (m *Message) TryPutMapFieldByNumber(tagNumber int, key interface{}, val interface{}) error {
+	fd := m.FindFieldDescriptor(int32(tagNumber))
+	if fd == nil {
+		return UnknownTagNumberError
+	}
+	return m.putMapField(fd, key, val)
+}
+
+func (m *Message) putMapField(fd *desc.FieldDescriptor, key interface{}, val interface{}) error {
+	if !fd.IsMap() {
+		return FieldIsNotMapError
+	}
+	kfd := fd.GetMessageType().GetFields()[0]
+	ki, err := validElementFieldValue(kfd, key, false)
+	if err != nil {
+		return err
+	}
+	vfd := fd.GetMessageType().GetFields()[1]
+	vi, err := validElementFieldValue(vfd, val, true)
+	if err != nil {
+		return err
+	}
+	mp := m.values[fd.GetNumber()]
+	if mp == nil {
+		if mp, err = m.parseUnknownField(fd); err != nil {
+			return err
+		} else if mp == nil {
+			m.internalSetField(fd, map[interface{}]interface{}{ki: vi})
+			return nil
+		}
+	}
+	mp.(map[interface{}]interface{})[ki] = vi
+	return nil
+}
+
+// RemoveMapField changes the value for the given field descriptor by removing
+// any value associated with the given key. It panics if an error is
+// encountered. See TryRemoveMapField.
+func (m *Message) RemoveMapField(fd *desc.FieldDescriptor, key interface{}) {
+	if err := m.TryRemoveMapField(fd, key); err != nil {
+		panic(err.Error())
+	}
+}
+
+// TryRemoveMapField changes the value for the given field descriptor by
+// removing any value associated with the given key. An error is returned if the
+// given field descriptor does not belong to the right message type or if the
+// given field is not a map field.
+//
+// If the given field descriptor is not known (e.g. not present in the message
+// descriptor) it will become known. Subsequent operations using tag numbers or
+// names will be able to resolve the newly-known type. If the message has a
+// value for the unknown value, it is parsed and any value for the given key
+// removed.
+func (m *Message) TryRemoveMapField(fd *desc.FieldDescriptor, key interface{}) error {
+	if err := m.checkField(fd); err != nil {
+		return err
+	}
+	return m.removeMapField(fd, key)
+}
+
+// RemoveMapFieldByName changes the value for the field with the given name by
+// removing any value associated with the given key. It panics if an error is
+// encountered. See TryRemoveMapFieldByName.
+func (m *Message) RemoveMapFieldByName(name string, key interface{}) {
+	if err := m.TryRemoveMapFieldByName(name, key); err != nil {
+		panic(err.Error())
+	}
+}
+
+// TryRemoveMapFieldByName changes the value for the field with the given name
+// by removing any value associated with the given key. An error is returned if
+// the given name is unknown or if it names a field that is not a map.
+func (m *Message) TryRemoveMapFieldByName(name string, key interface{}) error {
+	fd := m.FindFieldDescriptorByName(name)
+	if fd == nil {
+		return UnknownFieldNameError
+	}
+	return m.removeMapField(fd, key)
+}
+
+// RemoveMapFieldByNumber changes the value for the field with the given tag
+// number by removing any value associated with the given key. It panics if an
+// error is encountered. See TryRemoveMapFieldByNumber.
+func (m *Message) RemoveMapFieldByNumber(tagNumber int, key interface{}) {
+	if err := m.TryRemoveMapFieldByNumber(tagNumber, key); err != nil {
+		panic(err.Error())
+	}
+}
+
+// TryRemoveMapFieldByNumber changes the value for the field with the given tag
+// number by removing any value associated with the given key. An error is
+// returned if the given tag is unknown or if it indicates a field that is not
+// a map.
+func (m *Message) TryRemoveMapFieldByNumber(tagNumber int, key interface{}) error {
+	fd := m.FindFieldDescriptor(int32(tagNumber))
+	if fd == nil {
+		return UnknownTagNumberError
+	}
+	return m.removeMapField(fd, key)
+}
+
+func (m *Message) removeMapField(fd *desc.FieldDescriptor, key interface{}) error {
+	if !fd.IsMap() {
+		return FieldIsNotMapError
+	}
+	kfd := fd.GetMessageType().GetFields()[0]
+	ki, err := validElementFieldValue(kfd, key, false)
+	if err != nil {
+		return err
+	}
+	mp := m.values[fd.GetNumber()]
+	if mp == nil {
+		if mp, err = m.parseUnknownField(fd); err != nil {
+			return err
+		} else if mp == nil {
+			return nil
+		}
+	}
+	res := mp.(map[interface{}]interface{})
+	delete(res, ki)
+	if len(res) == 0 {
+		delete(m.values, fd.GetNumber())
+	}
+	return nil
+}
+
+// FieldLength returns the number of elements in this message for the given
+// field descriptor. It panics if an error is encountered. See TryFieldLength.
+func (m *Message) FieldLength(fd *desc.FieldDescriptor) int {
+	l, err := m.TryFieldLength(fd)
+	if err != nil {
+		panic(err.Error())
+	}
+	return l
+}
+
+// TryFieldLength returns the number of elements in this message for the given
+// field descriptor. An error is returned if the given field descriptor does not
+// belong to the right message type or if it is neither a map field nor a
+// repeated field.
+func (m *Message) TryFieldLength(fd *desc.FieldDescriptor) (int, error) {
+	if err := m.checkField(fd); err != nil {
+		return 0, err
+	}
+	return m.fieldLength(fd)
+}
+
+// FieldLengthByName returns the number of elements in this message for the
+// field with the given name. It panics if an error is encountered. See
+// TryFieldLengthByName.
+func (m *Message) FieldLengthByName(name string) int {
+	l, err := m.TryFieldLengthByName(name)
+	if err != nil {
+		panic(err.Error())
+	}
+	return l
+}
+
+// TryFieldLengthByName returns the number of elements in this message for the
+// field with the given name. An error is returned if the given name is unknown
+// or if the named field is neither a map field nor a repeated field.
+func (m *Message) TryFieldLengthByName(name string) (int, error) {
+	fd := m.FindFieldDescriptorByName(name)
+	if fd == nil {
+		return 0, UnknownFieldNameError
+	}
+	return m.fieldLength(fd)
+}
+
+// FieldLengthByNumber returns the number of elements in this message for the
+// field with the given tag number. It panics if an error is encountered. See
+// TryFieldLengthByNumber.
+func (m *Message) FieldLengthByNumber(tagNumber int32) int {
+	l, err := m.TryFieldLengthByNumber(tagNumber)
+	if err != nil {
+		panic(err.Error())
+	}
+	return l
+}
+
+// TryFieldLengthByNumber returns the number of elements in this message for the
+// field with the given tag number. An error is returned if the given tag is
+// unknown or if the named field is neither a map field nor a repeated field.
+func (m *Message) TryFieldLengthByNumber(tagNumber int32) (int, error) {
+	fd := m.FindFieldDescriptor(int32(tagNumber))
+	if fd == nil {
+		return 0, UnknownTagNumberError
+	}
+	return m.fieldLength(fd)
+}
+
+func (m *Message) fieldLength(fd *desc.FieldDescriptor) (int, error) {
+	if !fd.IsRepeated() {
+		return 0, FieldIsNotRepeatedError
+	}
+	val := m.values[fd.GetNumber()]
+	if val == nil {
+		var err error
+		if val, err = m.parseUnknownField(fd); err != nil {
+			return 0, err
+		} else if val == nil {
+			return 0, nil
+		}
+	}
+	if sl, ok := val.([]interface{}); ok {
+		return len(sl), nil
+	} else if mp, ok := val.(map[interface{}]interface{}); ok {
+		return len(mp), nil
+	}
+	return 0, nil
+}
+
+// GetRepeatedField returns the value for the given repeated field descriptor at
+// the given index. It panics if an error is encountered. See
+// TryGetRepeatedField.
+func (m *Message) GetRepeatedField(fd *desc.FieldDescriptor, index int) interface{} {
+	if v, err := m.TryGetRepeatedField(fd, index); err != nil {
+		panic(err.Error())
+	} else {
+		return v
+	}
+}
+
+// TryGetRepeatedField returns the value for the given repeated field descriptor
+// at the given index. An error is returned if the given field descriptor does
+// not belong to the right message type, if it is not a repeated field, or if
+// the given index is out of range (less than zero or greater than or equal to
+// the length of the repeated field). Also, even though map fields technically
+// are repeated fields, if the given field is a map field an error will result:
+// map representation does not lend itself to random access by index.
+//
+// The Go type of the value returned mirrors the type that protoc would generate
+// for the field's element type. (See TryGetField for more details on types).
+//
+// If the given field descriptor is not known (e.g. not present in the message
+// descriptor) but corresponds to an unknown field, the unknown value will be
+// parsed and become known. The value at the given index in the parsed value
+// will be returned. An error will be returned if the unknown value cannot be
+// parsed according to the field descriptor's type information.
+func (m *Message) TryGetRepeatedField(fd *desc.FieldDescriptor, index int) (interface{}, error) {
+	if index < 0 {
+		return nil, IndexOutOfRangeError
+	}
+	if err := m.checkField(fd); err != nil {
+		return nil, err
+	}
+	return m.getRepeatedField(fd, index)
+}
+
+// GetRepeatedFieldByName returns the value for the repeated field with the
+// given name at the given index. It panics if an error is encountered. See
+// TryGetRepeatedFieldByName.
+func (m *Message) GetRepeatedFieldByName(name string, index int) interface{} {
+	if v, err := m.TryGetRepeatedFieldByName(name, index); err != nil {
+		panic(err.Error())
+	} else {
+		return v
+	}
+}
+
+// TryGetRepeatedFieldByName returns the value for the repeated field with the
+// given name at the given index. An error is returned if the given name is
+// unknown, if it names a field that is not a repeated field (or is a map
+// field), or if the given index is out of range (less than zero or greater
+// than or equal to the length of the repeated field).
+//
+// (See TryGetField for more info on types.)
+func (m *Message) TryGetRepeatedFieldByName(name string, index int) (interface{}, error) {
+	if index < 0 {
+		return nil, IndexOutOfRangeError
+	}
+	fd := m.FindFieldDescriptorByName(name)
+	if fd == nil {
+		return nil, UnknownFieldNameError
+	}
+	return m.getRepeatedField(fd, index)
+}
+
+// GetRepeatedFieldByNumber returns the value for the repeated field with the
+// given tag number at the given index. It panics if an error is encountered.
+// See TryGetRepeatedFieldByNumber.
+func (m *Message) GetRepeatedFieldByNumber(tagNumber int, index int) interface{} {
+	if v, err := m.TryGetRepeatedFieldByNumber(tagNumber, index); err != nil {
+		panic(err.Error())
+	} else {
+		return v
+	}
+}
+
+// TryGetRepeatedFieldByNumber returns the value for the repeated field with the
+// given tag number at the given index. An error is returned if the given tag is
+// unknown, if it indicates a field that is not a repeated field (or is a map
+// field), or if the given index is out of range (less than zero or greater than
+// or equal to the length of the repeated field).
+//
+// (See TryGetField for more info on types.)
+func (m *Message) TryGetRepeatedFieldByNumber(tagNumber int, index int) (interface{}, error) {
+	if index < 0 {
+		return nil, IndexOutOfRangeError
+	}
+	fd := m.FindFieldDescriptor(int32(tagNumber))
+	if fd == nil {
+		return nil, UnknownTagNumberError
+	}
+	return m.getRepeatedField(fd, index)
+}
+
+func (m *Message) getRepeatedField(fd *desc.FieldDescriptor, index int) (interface{}, error) {
+	if fd.IsMap() || !fd.IsRepeated() {
+		return nil, FieldIsNotRepeatedError
+	}
+	sl := m.values[fd.GetNumber()]
+	if sl == nil {
+		var err error
+		if sl, err = m.parseUnknownField(fd); err != nil {
+			return nil, err
+		} else if sl == nil {
+			return nil, IndexOutOfRangeError
+		}
+	}
+	res := sl.([]interface{})
+	if index >= len(res) {
+		return nil, IndexOutOfRangeError
+	}
+	return res[index], nil
+}
+
+// AddRepeatedField appends the given value to the given repeated field. It
+// panics if an error is encountered. See TryAddRepeatedField.
+func (m *Message) AddRepeatedField(fd *desc.FieldDescriptor, val interface{}) {
+	if err := m.TryAddRepeatedField(fd, val); err != nil {
+		panic(err.Error())
+	}
+}
+
+// TryAddRepeatedField appends the given value to the given repeated field. An
+// error is returned if the given field descriptor does not belong to the right
+// message type, if the given field is not repeated, or if the given value is
+// not a correct/compatible type for the given field. If the given field is a
+// map field, the call will succeed if the given value is an instance of the
+// map's entry message type.
+//
+// The Go type expected for a field  is the same as required by TrySetField for
+// a non-repeated field of the same type.
+//
+// If the given field descriptor is not known (e.g. not present in the message
+// descriptor) it will become known. Subsequent operations using tag numbers or
+// names will be able to resolve the newly-known type. If the message has a
+// value for the unknown value, it is parsed and the given value is appended to
+// it.
+func (m *Message) TryAddRepeatedField(fd *desc.FieldDescriptor, val interface{}) error {
+	if err := m.checkField(fd); err != nil {
+		return err
+	}
+	return m.addRepeatedField(fd, val)
+}
+
+// AddRepeatedFieldByName appends the given value to the repeated field with the
+// given name. It panics if an error is encountered. See
+// TryAddRepeatedFieldByName.
+func (m *Message) AddRepeatedFieldByName(name string, val interface{}) {
+	if err := m.TryAddRepeatedFieldByName(name, val); err != nil {
+		panic(err.Error())
+	}
+}
+
+// TryAddRepeatedFieldByName appends the given value to the repeated field with
+// the given name. An error is returned if the given name is unknown, if it
+// names a field that is not repeated, or if the given value has an incorrect
+// type.
+//
+// (See TrySetField for more info on types.)
+func (m *Message) TryAddRepeatedFieldByName(name string, val interface{}) error {
+	fd := m.FindFieldDescriptorByName(name)
+	if fd == nil {
+		return UnknownFieldNameError
+	}
+	return m.addRepeatedField(fd, val)
+}
+
+// AddRepeatedFieldByNumber appends the given value to the repeated field with
+// the given tag number. It panics if an error is encountered. See
+// TryAddRepeatedFieldByNumber.
+func (m *Message) AddRepeatedFieldByNumber(tagNumber int, val interface{}) {
+	if err := m.TryAddRepeatedFieldByNumber(tagNumber, val); err != nil {
+		panic(err.Error())
+	}
+}
+
+// TryAddRepeatedFieldByNumber appends the given value to the repeated field
+// with the given tag number. An error is returned if the given tag is unknown,
+// if it indicates a field that is not repeated, or if the given value has an
+// incorrect type.
+//
+// (See TrySetField for more info on types.)
+func (m *Message) TryAddRepeatedFieldByNumber(tagNumber int, val interface{}) error {
+	fd := m.FindFieldDescriptor(int32(tagNumber))
+	if fd == nil {
+		return UnknownTagNumberError
+	}
+	return m.addRepeatedField(fd, val)
+}
+
+func (m *Message) addRepeatedField(fd *desc.FieldDescriptor, val interface{}) error {
+	if !fd.IsRepeated() {
+		return FieldIsNotRepeatedError
+	}
+	val, err := validElementFieldValue(fd, val, false)
+	if err != nil {
+		return err
+	}
+
+	if fd.IsMap() {
+		// We're lenient. Just as we allow setting a map field to a slice of entry messages, we also allow
+		// adding entries one at a time (as if the field were a normal repeated field).
+		msg := val.(proto.Message)
+		dm, err := asDynamicMessage(msg, fd.GetMessageType(), m.mf)
+		if err != nil {
+			return err
+		}
+		k, err := dm.TryGetFieldByNumber(1)
+		if err != nil {
+			return err
+		}
+		v, err := dm.TryGetFieldByNumber(2)
+		if err != nil {
+			return err
+		}
+		return m.putMapField(fd, k, v)
+	}
+
+	sl := m.values[fd.GetNumber()]
+	if sl == nil {
+		if sl, err = m.parseUnknownField(fd); err != nil {
+			return err
+		} else if sl == nil {
+			sl = []interface{}{}
+		}
+	}
+	res := sl.([]interface{})
+	res = append(res, val)
+	m.internalSetField(fd, res)
+	return nil
+}
+
+// SetRepeatedField sets the value for the given repeated field descriptor and
+// given index to the given value. It panics if an error is encountered. See
+// SetRepeatedField.
+func (m *Message) SetRepeatedField(fd *desc.FieldDescriptor, index int, val interface{}) {
+	if err := m.TrySetRepeatedField(fd, index, val); err != nil {
+		panic(err.Error())
+	}
+}
+
+// TrySetRepeatedField sets the value for the given repeated field descriptor
+// and given index to the given value. An error is returned if the given field
+// descriptor does not belong to the right message type, if the given field is
+// not repeated, or if the given value is not a correct/compatible type for the
+// given field. Also, even though map fields technically are repeated fields, if
+// the given field is a map field an error will result: map representation does
+// not lend itself to random access by index.
+//
+// The Go type expected for a field  is the same as required by TrySetField for
+// a non-repeated field of the same type.
+//
+// If the given field descriptor is not known (e.g. not present in the message
+// descriptor) it will become known. Subsequent operations using tag numbers or
+// names will be able to resolve the newly-known type. If the message has a
+// value for the unknown value, it is parsed and the element at the given index
+// is replaced with the given value.
+func (m *Message) TrySetRepeatedField(fd *desc.FieldDescriptor, index int, val interface{}) error {
+	if index < 0 {
+		return IndexOutOfRangeError
+	}
+	if err := m.checkField(fd); err != nil {
+		return err
+	}
+	return m.setRepeatedField(fd, index, val)
+}
+
+// SetRepeatedFieldByName sets the value for the repeated field with the given
+// name and given index to the given value. It panics if an error is
+// encountered. See TrySetRepeatedFieldByName.
+func (m *Message) SetRepeatedFieldByName(name string, index int, val interface{}) {
+	if err := m.TrySetRepeatedFieldByName(name, index, val); err != nil {
+		panic(err.Error())
+	}
+}
+
+// TrySetRepeatedFieldByName sets the value for the repeated field with the
+// given name and the given index to the given value. An error is returned if
+// the given name is unknown, if it names a field that is not repeated (or is a
+// map field), or if the given value has an incorrect type.
+//
+// (See TrySetField for more info on types.)
+func (m *Message) TrySetRepeatedFieldByName(name string, index int, val interface{}) error {
+	if index < 0 {
+		return IndexOutOfRangeError
+	}
+	fd := m.FindFieldDescriptorByName(name)
+	if fd == nil {
+		return UnknownFieldNameError
+	}
+	return m.setRepeatedField(fd, index, val)
+}
+
+// SetRepeatedFieldByNumber sets the value for the repeated field with the given
+// tag number and given index to the given value. It panics if an error is
+// encountered. See TrySetRepeatedFieldByNumber.
+func (m *Message) SetRepeatedFieldByNumber(tagNumber int, index int, val interface{}) {
+	if err := m.TrySetRepeatedFieldByNumber(tagNumber, index, val); err != nil {
+		panic(err.Error())
+	}
+}
+
+// TrySetRepeatedFieldByNumber sets the value for the repeated field with the
+// given tag number and the given index to the given value. An error is returned
+// if the given tag is unknown, if it indicates a field that is not repeated (or
+// is a map field), or if the given value has an incorrect type.
+//
+// (See TrySetField for more info on types.)
+func (m *Message) TrySetRepeatedFieldByNumber(tagNumber int, index int, val interface{}) error {
+	if index < 0 {
+		return IndexOutOfRangeError
+	}
+	fd := m.FindFieldDescriptor(int32(tagNumber))
+	if fd == nil {
+		return UnknownTagNumberError
+	}
+	return m.setRepeatedField(fd, index, val)
+}
+
+func (m *Message) setRepeatedField(fd *desc.FieldDescriptor, index int, val interface{}) error {
+	if fd.IsMap() || !fd.IsRepeated() {
+		return FieldIsNotRepeatedError
+	}
+	val, err := validElementFieldValue(fd, val, false)
+	if err != nil {
+		return err
+	}
+	sl := m.values[fd.GetNumber()]
+	if sl == nil {
+		if sl, err = m.parseUnknownField(fd); err != nil {
+			return err
+		} else if sl == nil {
+			return IndexOutOfRangeError
+		}
+	}
+	res := sl.([]interface{})
+	if index >= len(res) {
+		return IndexOutOfRangeError
+	}
+	res[index] = val
+	return nil
+}
+
+// GetUnknownField gets the value(s) for the given unknown tag number. If this
+// message has no unknown fields with the given tag, nil is returned.
+func (m *Message) GetUnknownField(tagNumber int32) []UnknownField {
+	if u, ok := m.unknownFields[tagNumber]; ok {
+		return u
+	} else {
+		return nil
+	}
+}
+
+func (m *Message) parseUnknownField(fd *desc.FieldDescriptor) (interface{}, error) {
+	unks, ok := m.unknownFields[fd.GetNumber()]
+	if !ok {
+		return nil, nil
+	}
+	var v interface{}
+	var sl []interface{}
+	var mp map[interface{}]interface{}
+	if fd.IsMap() {
+		mp = map[interface{}]interface{}{}
+	}
+	var err error
+	for _, unk := range unks {
+		var val interface{}
+		if unk.Encoding == proto.WireBytes || unk.Encoding == proto.WireStartGroup {
+			val, err = codec.DecodeLengthDelimitedField(fd, unk.Contents, m.mf)
+		} else {
+			val, err = codec.DecodeScalarField(fd, unk.Value)
+		}
+		if err != nil {
+			return nil, err
+		}
+		if fd.IsMap() {
+			newEntry := val.(*Message)
+			kk, err := newEntry.TryGetFieldByNumber(1)
+			if err != nil {
+				return nil, err
+			}
+			vv, err := newEntry.TryGetFieldByNumber(2)
+			if err != nil {
+				return nil, err
+			}
+			mp[kk] = vv
+			v = mp
+		} else if fd.IsRepeated() {
+			t := reflect.TypeOf(val)
+			if t.Kind() == reflect.Slice && t != typeOfBytes {
+				// append slices if we unmarshalled a packed repeated field
+				newVals := val.([]interface{})
+				sl = append(sl, newVals...)
+			} else {
+				sl = append(sl, val)
+			}
+			v = sl
+		} else {
+			v = val
+		}
+	}
+	m.internalSetField(fd, v)
+	return v, nil
+}
+
+func validFieldValue(fd *desc.FieldDescriptor, val interface{}) (interface{}, error) {
+	return validFieldValueForRv(fd, reflect.ValueOf(val))
+}
+
+func validFieldValueForRv(fd *desc.FieldDescriptor, val reflect.Value) (interface{}, error) {
+	if fd.IsMap() && val.Kind() == reflect.Map {
+		return validFieldValueForMapField(fd, val)
+	}
+
+	if fd.IsRepeated() { // this will also catch map fields where given value was not a map
+		if val.Kind() != reflect.Array && val.Kind() != reflect.Slice {
+			if fd.IsMap() {
+				return nil, fmt.Errorf("value for map field must be a map; instead was %v", val.Type())
+			} else {
+				return nil, fmt.Errorf("value for repeated field must be a slice; instead was %v", val.Type())
+			}
+		}
+
+		if fd.IsMap() {
+			// value should be a slice of entry messages that we need convert into a map[interface{}]interface{}
+			m := map[interface{}]interface{}{}
+			for i := 0; i < val.Len(); i++ {
+				e, err := validElementFieldValue(fd, val.Index(i).Interface(), false)
+				if err != nil {
+					return nil, err
+				}
+				msg := e.(proto.Message)
+				dm, err := asDynamicMessage(msg, fd.GetMessageType(), nil)
+				if err != nil {
+					return nil, err
+				}
+				k, err := dm.TryGetFieldByNumber(1)
+				if err != nil {
+					return nil, err
+				}
+				v, err := dm.TryGetFieldByNumber(2)
+				if err != nil {
+					return nil, err
+				}
+				m[k] = v
+			}
+			return m, nil
+		}
+
+		// make a defensive copy while checking contents (also converts to []interface{})
+		s := make([]interface{}, val.Len())
+		for i := 0; i < val.Len(); i++ {
+			ev := val.Index(i)
+			if ev.Kind() == reflect.Interface {
+				// unwrap it
+				ev = reflect.ValueOf(ev.Interface())
+			}
+			e, err := validElementFieldValueForRv(fd, ev, false)
+			if err != nil {
+				return nil, err
+			}
+			s[i] = e
+		}
+
+		return s, nil
+	}
+
+	return validElementFieldValueForRv(fd, val, false)
+}
+
+func asDynamicMessage(m proto.Message, md *desc.MessageDescriptor, mf *MessageFactory) (*Message, error) {
+	if dm, ok := m.(*Message); ok {
+		return dm, nil
+	}
+	dm := NewMessageWithMessageFactory(md, mf)
+	if err := dm.mergeFrom(m); err != nil {
+		return nil, err
+	}
+	return dm, nil
+}
+
+func validElementFieldValue(fd *desc.FieldDescriptor, val interface{}, allowNilMessage bool) (interface{}, error) {
+	return validElementFieldValueForRv(fd, reflect.ValueOf(val), allowNilMessage)
+}
+
+func validElementFieldValueForRv(fd *desc.FieldDescriptor, val reflect.Value, allowNilMessage bool) (interface{}, error) {
+	t := fd.GetType()
+	if !val.IsValid() {
+		return nil, typeError(fd, nil)
+	}
+
+	switch t {
+	case descriptor.FieldDescriptorProto_TYPE_SFIXED32,
+		descriptor.FieldDescriptorProto_TYPE_INT32,
+		descriptor.FieldDescriptorProto_TYPE_SINT32,
+		descriptor.FieldDescriptorProto_TYPE_ENUM:
+		return toInt32(reflect.Indirect(val), fd)
+
+	case descriptor.FieldDescriptorProto_TYPE_SFIXED64,
+		descriptor.FieldDescriptorProto_TYPE_INT64,
+		descriptor.FieldDescriptorProto_TYPE_SINT64:
+		return toInt64(reflect.Indirect(val), fd)
+
+	case descriptor.FieldDescriptorProto_TYPE_FIXED32,
+		descriptor.FieldDescriptorProto_TYPE_UINT32:
+		return toUint32(reflect.Indirect(val), fd)
+
+	case descriptor.FieldDescriptorProto_TYPE_FIXED64,
+		descriptor.FieldDescriptorProto_TYPE_UINT64:
+		return toUint64(reflect.Indirect(val), fd)
+
+	case descriptor.FieldDescriptorProto_TYPE_FLOAT:
+		return toFloat32(reflect.Indirect(val), fd)
+
+	case descriptor.FieldDescriptorProto_TYPE_DOUBLE:
+		return toFloat64(reflect.Indirect(val), fd)
+
+	case descriptor.FieldDescriptorProto_TYPE_BOOL:
+		return toBool(reflect.Indirect(val), fd)
+
+	case descriptor.FieldDescriptorProto_TYPE_BYTES:
+		return toBytes(reflect.Indirect(val), fd)
+
+	case descriptor.FieldDescriptorProto_TYPE_STRING:
+		return toString(reflect.Indirect(val), fd)
+
+	case descriptor.FieldDescriptorProto_TYPE_MESSAGE,
+		descriptor.FieldDescriptorProto_TYPE_GROUP:
+		m, err := asMessage(val, fd.GetFullyQualifiedName())
+		// check that message is correct type
+		if err != nil {
+			return nil, err
+		}
+		var msgType string
+		if dm, ok := m.(*Message); ok {
+			if allowNilMessage && dm == nil {
+				// if dm == nil, we'll panic below, so early out if that is allowed
+				// (only allowed for map values, to indicate an entry w/ no value)
+				return m, nil
+			}
+			msgType = dm.GetMessageDescriptor().GetFullyQualifiedName()
+		} else {
+			msgType = proto.MessageName(m)
+		}
+		if msgType != fd.GetMessageType().GetFullyQualifiedName() {
+			return nil, fmt.Errorf("message field %s requires value of type %s; received %s", fd.GetFullyQualifiedName(), fd.GetMessageType().GetFullyQualifiedName(), msgType)
+		}
+		return m, nil
+
+	default:
+		return nil, fmt.Errorf("unable to handle unrecognized field type: %v", fd.GetType())
+	}
+}
+
+func toInt32(v reflect.Value, fd *desc.FieldDescriptor) (int32, error) {
+	if v.Kind() == reflect.Int32 {
+		return int32(v.Int()), nil
+	}
+	return 0, typeError(fd, v.Type())
+}
+
+func toUint32(v reflect.Value, fd *desc.FieldDescriptor) (uint32, error) {
+	if v.Kind() == reflect.Uint32 {
+		return uint32(v.Uint()), nil
+	}
+	return 0, typeError(fd, v.Type())
+}
+
+func toFloat32(v reflect.Value, fd *desc.FieldDescriptor) (float32, error) {
+	if v.Kind() == reflect.Float32 {
+		return float32(v.Float()), nil
+	}
+	return 0, typeError(fd, v.Type())
+}
+
+func toInt64(v reflect.Value, fd *desc.FieldDescriptor) (int64, error) {
+	if v.Kind() == reflect.Int64 || v.Kind() == reflect.Int || v.Kind() == reflect.Int32 {
+		return v.Int(), nil
+	}
+	return 0, typeError(fd, v.Type())
+}
+
+func toUint64(v reflect.Value, fd *desc.FieldDescriptor) (uint64, error) {
+	if v.Kind() == reflect.Uint64 || v.Kind() == reflect.Uint || v.Kind() == reflect.Uint32 {
+		return v.Uint(), nil
+	}
+	return 0, typeError(fd, v.Type())
+}
+
+func toFloat64(v reflect.Value, fd *desc.FieldDescriptor) (float64, error) {
+	if v.Kind() == reflect.Float64 || v.Kind() == reflect.Float32 {
+		return v.Float(), nil
+	}
+	return 0, typeError(fd, v.Type())
+}
+
+func toBool(v reflect.Value, fd *desc.FieldDescriptor) (bool, error) {
+	if v.Kind() == reflect.Bool {
+		return v.Bool(), nil
+	}
+	return false, typeError(fd, v.Type())
+}
+
+func toBytes(v reflect.Value, fd *desc.FieldDescriptor) ([]byte, error) {
+	if v.Kind() == reflect.Slice && v.Type().Elem().Kind() == reflect.Uint8 {
+		return v.Bytes(), nil
+	}
+	return nil, typeError(fd, v.Type())
+}
+
+func toString(v reflect.Value, fd *desc.FieldDescriptor) (string, error) {
+	if v.Kind() == reflect.String {
+		return v.String(), nil
+	}
+	return "", typeError(fd, v.Type())
+}
+
+func typeError(fd *desc.FieldDescriptor, t reflect.Type) error {
+	return fmt.Errorf(
+		"%s field %s is not compatible with value of type %v",
+		getTypeString(fd), fd.GetFullyQualifiedName(), t)
+}
+
+func getTypeString(fd *desc.FieldDescriptor) string {
+	return strings.ToLower(fd.GetType().String())
+}
+
+func asMessage(v reflect.Value, fieldName string) (proto.Message, error) {
+	t := v.Type()
+	// we need a pointer to a struct that implements proto.Message
+	if t.Kind() != reflect.Ptr || t.Elem().Kind() != reflect.Struct || !t.Implements(typeOfProtoMessage) {
+		return nil, fmt.Errorf("message field %s requires is not compatible with value of type %v", fieldName, v.Type())
+	}
+	return v.Interface().(proto.Message), nil
+}
+
+// Reset resets this message to an empty message. It removes all values set in
+// the message.
+func (m *Message) Reset() {
+	for k := range m.values {
+		delete(m.values, k)
+	}
+	for k := range m.unknownFields {
+		delete(m.unknownFields, k)
+	}
+}
+
+// String returns this message rendered in compact text format.
+func (m *Message) String() string {
+	b, err := m.MarshalText()
+	if err != nil {
+		panic(fmt.Sprintf("Failed to create string representation of message: %s", err.Error()))
+	}
+	return string(b)
+}
+
+// ProtoMessage is present to satisfy the proto.Message interface.
+func (m *Message) ProtoMessage() {
+}
+
+// ConvertTo converts this dynamic message into the given message. This is
+// shorthand for resetting then merging:
+//   target.Reset()
+//   m.MergeInto(target)
+func (m *Message) ConvertTo(target proto.Message) error {
+	if err := m.checkType(target); err != nil {
+		return err
+	}
+
+	target.Reset()
+	return m.mergeInto(target, defaultDeterminism)
+}
+
+// ConvertToDeterministic converts this dynamic message into the given message.
+// It is just like ConvertTo, but it attempts to produce deterministic results.
+// That means that if the target is a generated message (not another dynamic
+// message) and the current runtime is unaware of any fields or extensions that
+// are present in m, they will be serialized into the target's unrecognized
+// fields deterministically.
+func (m *Message) ConvertToDeterministic(target proto.Message) error {
+	if err := m.checkType(target); err != nil {
+		return err
+	}
+
+	target.Reset()
+	return m.mergeInto(target, true)
+}
+
+// ConvertFrom converts the given message into this dynamic message. This is
+// shorthand for resetting then merging:
+//   m.Reset()
+//   m.MergeFrom(target)
+func (m *Message) ConvertFrom(target proto.Message) error {
+	if err := m.checkType(target); err != nil {
+		return err
+	}
+
+	m.Reset()
+	return m.mergeFrom(target)
+}
+
+// MergeInto merges this dynamic message into the given message. All field
+// values in this message will be set on the given message. For map fields,
+// entries are added to the given message (if the given message has existing
+// values for like keys, they are overwritten). For slice fields, elements are
+// added.
+//
+// If the given message has a different set of known fields, it is possible for
+// some known fields in this message to be represented as unknown fields in the
+// given message after merging, and vice versa.
+func (m *Message) MergeInto(target proto.Message) error {
+	if err := m.checkType(target); err != nil {
+		return err
+	}
+	return m.mergeInto(target, defaultDeterminism)
+}
+
+// MergeIntoDeterministic merges this dynamic message into the given message.
+// It is just like MergeInto, but it attempts to produce deterministic results.
+// That means that if the target is a generated message (not another dynamic
+// message) and the current runtime is unaware of any fields or extensions that
+// are present in m, they will be serialized into the target's unrecognized
+// fields deterministically.
+func (m *Message) MergeIntoDeterministic(target proto.Message) error {
+	if err := m.checkType(target); err != nil {
+		return err
+	}
+	return m.mergeInto(target, true)
+}
+
+// MergeFrom merges the given message into this dynamic message. All field
+// values in the given message will be set on this message. For map fields,
+// entries are added to this message (if this message has existing values for
+// like keys, they are overwritten). For slice fields, elements are added.
+//
+// If the given message has a different set of known fields, it is possible for
+// some known fields in that message to be represented as unknown fields in this
+// message after merging, and vice versa.
+func (m *Message) MergeFrom(source proto.Message) error {
+	if err := m.checkType(source); err != nil {
+		return err
+	}
+	return m.mergeFrom(source)
+}
+
+// Merge implements the proto.Merger interface so that dynamic messages are
+// compatible with the proto.Merge function. It delegates to MergeFrom but will
+// panic on error as the proto.Merger interface doesn't allow for returning an
+// error.
+//
+// Unlike nearly all other methods, this method can work if this message's type
+// is not defined (such as instantiating the message without using NewMessage).
+// This is strictly so that dynamic message's are compatible with the
+// proto.Clone function, which instantiates a new message via reflection (thus
+// its message descriptor will not be set) and than calls Merge.
+func (m *Message) Merge(source proto.Message) {
+	if m.md == nil {
+		// To support proto.Clone, initialize the descriptor from the source.
+		if dm, ok := source.(*Message); ok {
+			m.md = dm.md
+			// also make sure the clone uses the same message factory and
+			// extensions and also knows about the same extra fields (if any)
+			m.mf = dm.mf
+			m.er = dm.er
+			m.extraFields = dm.extraFields
+		} else if md, err := desc.LoadMessageDescriptorForMessage(source); err != nil {
+			panic(err.Error())
+		} else {
+			m.md = md
+		}
+	}
+
+	if err := m.MergeFrom(source); err != nil {
+		panic(err.Error())
+	}
+}
+
+func (m *Message) checkType(target proto.Message) error {
+	if dm, ok := target.(*Message); ok {
+		if dm.md.GetFullyQualifiedName() != m.md.GetFullyQualifiedName() {
+			return fmt.Errorf("given message has wrong type: %q; expecting %q", dm.md.GetFullyQualifiedName(), m.md.GetFullyQualifiedName())
+		}
+		return nil
+	}
+
+	msgName := proto.MessageName(target)
+	if msgName != m.md.GetFullyQualifiedName() {
+		return fmt.Errorf("given message has wrong type: %q; expecting %q", msgName, m.md.GetFullyQualifiedName())
+	}
+	return nil
+}
+
+func (m *Message) mergeInto(pm proto.Message, deterministic bool) error {
+	if dm, ok := pm.(*Message); ok {
+		return dm.mergeFrom(m)
+	}
+
+	target := reflect.ValueOf(pm)
+	if target.Kind() == reflect.Ptr {
+		target = target.Elem()
+	}
+
+	// track tags for which the dynamic message has data but the given
+	// message doesn't know about it
+	unknownTags := map[int32]struct{}{}
+	for tag := range m.values {
+		unknownTags[tag] = struct{}{}
+	}
+
+	// check that we can successfully do the merge
+	structProps := proto.GetProperties(reflect.TypeOf(pm).Elem())
+	for _, prop := range structProps.Prop {
+		if prop.Tag == 0 {
+			continue // one-of or special field (such as XXX_unrecognized, etc.)
+		}
+		tag := int32(prop.Tag)
+		v, ok := m.values[tag]
+		if !ok {
+			continue
+		}
+		if unknownTags != nil {
+			delete(unknownTags, tag)
+		}
+		f := target.FieldByName(prop.Name)
+		ft := f.Type()
+		val := reflect.ValueOf(v)
+		if !canConvert(val, ft) {
+			return fmt.Errorf("cannot convert %v to %v", val.Type(), ft)
+		}
+	}
+	// check one-of fields
+	for _, oop := range structProps.OneofTypes {
+		prop := oop.Prop
+		tag := int32(prop.Tag)
+		v, ok := m.values[tag]
+		if !ok {
+			continue
+		}
+		if unknownTags != nil {
+			delete(unknownTags, tag)
+		}
+		stf, ok := oop.Type.Elem().FieldByName(prop.Name)
+		if !ok {
+			return fmt.Errorf("one-of field indicates struct field name %s, but type %v has no such field", prop.Name, oop.Type.Elem())
+		}
+		ft := stf.Type
+		val := reflect.ValueOf(v)
+		if !canConvert(val, ft) {
+			return fmt.Errorf("cannot convert %v to %v", val.Type(), ft)
+		}
+	}
+	// and check extensions, too
+	for tag, ext := range proto.RegisteredExtensions(pm) {
+		v, ok := m.values[tag]
+		if !ok {
+			continue
+		}
+		if unknownTags != nil {
+			delete(unknownTags, tag)
+		}
+		ft := reflect.TypeOf(ext.ExtensionType)
+		val := reflect.ValueOf(v)
+		if !canConvert(val, ft) {
+			return fmt.Errorf("cannot convert %v to %v", val.Type(), ft)
+		}
+	}
+
+	// now actually perform the merge
+	for _, prop := range structProps.Prop {
+		v, ok := m.values[int32(prop.Tag)]
+		if !ok {
+			continue
+		}
+		f := target.FieldByName(prop.Name)
+		if err := mergeVal(reflect.ValueOf(v), f, deterministic); err != nil {
+			return err
+		}
+	}
+	// merge one-ofs
+	for _, oop := range structProps.OneofTypes {
+		prop := oop.Prop
+		tag := int32(prop.Tag)
+		v, ok := m.values[tag]
+		if !ok {
+			continue
+		}
+		oov := reflect.New(oop.Type.Elem())
+		f := oov.Elem().FieldByName(prop.Name)
+		if err := mergeVal(reflect.ValueOf(v), f, deterministic); err != nil {
+			return err
+		}
+		target.Field(oop.Field).Set(oov)
+	}
+	// merge extensions, too
+	for tag, ext := range proto.RegisteredExtensions(pm) {
+		v, ok := m.values[tag]
+		if !ok {
+			continue
+		}
+		e := reflect.New(reflect.TypeOf(ext.ExtensionType)).Elem()
+		if err := mergeVal(reflect.ValueOf(v), e, deterministic); err != nil {
+			return err
+		}
+		if err := proto.SetExtension(pm, ext, e.Interface()); err != nil {
+			// shouldn't happen since we already checked that the extension type was compatible above
+			return err
+		}
+	}
+
+	// if we have fields that the given message doesn't know about, add to its unknown fields
+	if len(unknownTags) > 0 {
+		var b codec.Buffer
+		b.SetDeterministic(deterministic)
+		if deterministic {
+			// if we need to emit things deterministically, sort the
+			// extensions by their tag number
+			sortedUnknownTags := make([]int32, 0, len(unknownTags))
+			for tag := range unknownTags {
+				sortedUnknownTags = append(sortedUnknownTags, tag)
+			}
+			sort.Slice(sortedUnknownTags, func(i, j int) bool {
+				return sortedUnknownTags[i] < sortedUnknownTags[j]
+			})
+			for _, tag := range sortedUnknownTags {
+				fd := m.FindFieldDescriptor(tag)
+				if err := b.EncodeFieldValue(fd, m.values[tag]); err != nil {
+					return err
+				}
+			}
+		} else {
+			for tag := range unknownTags {
+				fd := m.FindFieldDescriptor(tag)
+				if err := b.EncodeFieldValue(fd, m.values[tag]); err != nil {
+					return err
+				}
+			}
+		}
+
+		internal.SetUnrecognized(pm, b.Bytes())
+	}
+
+	// finally, convey unknown fields into the given message by letting it unmarshal them
+	// (this will append to its unknown fields if not known; if somehow the given message recognizes
+	// a field even though the dynamic message did not, it will get correctly unmarshalled)
+	if unknownTags != nil && len(m.unknownFields) > 0 {
+		var b codec.Buffer
+		_ = m.marshalUnknownFields(&b)
+		_ = proto.UnmarshalMerge(b.Bytes(), pm)
+	}
+
+	return nil
+}
+
+func canConvert(src reflect.Value, target reflect.Type) bool {
+	if src.Kind() == reflect.Interface {
+		src = reflect.ValueOf(src.Interface())
+	}
+	srcType := src.Type()
+	// we allow convertible types instead of requiring exact types so that calling
+	// code can, for example, assign an enum constant to an enum field. In that case,
+	// one type is the enum type (a sub-type of int32) and the other may be the int32
+	// type. So we automatically do the conversion in that case.
+	if srcType.ConvertibleTo(target) {
+		return true
+	} else if target.Kind() == reflect.Ptr && srcType.ConvertibleTo(target.Elem()) {
+		return true
+	} else if target.Kind() == reflect.Slice {
+		if srcType.Kind() != reflect.Slice {
+			return false
+		}
+		et := target.Elem()
+		for i := 0; i < src.Len(); i++ {
+			if !canConvert(src.Index(i), et) {
+				return false
+			}
+		}
+		return true
+	} else if target.Kind() == reflect.Map {
+		if srcType.Kind() != reflect.Map {
+			return false
+		}
+		return canConvertMap(src, target)
+	} else if srcType == typeOfDynamicMessage && target.Implements(typeOfProtoMessage) {
+		z := reflect.Zero(target).Interface()
+		msgType := proto.MessageName(z.(proto.Message))
+		return msgType == src.Interface().(*Message).GetMessageDescriptor().GetFullyQualifiedName()
+	} else {
+		return false
+	}
+}
+
+func mergeVal(src, target reflect.Value, deterministic bool) error {
+	if src.Kind() == reflect.Interface && !src.IsNil() {
+		src = src.Elem()
+	}
+	srcType := src.Type()
+	targetType := target.Type()
+	if srcType.ConvertibleTo(targetType) {
+		if targetType.Implements(typeOfProtoMessage) && !target.IsNil() {
+			Merge(target.Interface().(proto.Message), src.Convert(targetType).Interface().(proto.Message))
+		} else {
+			target.Set(src.Convert(targetType))
+		}
+	} else if targetType.Kind() == reflect.Ptr && srcType.ConvertibleTo(targetType.Elem()) {
+		if !src.CanAddr() {
+			target.Set(reflect.New(targetType.Elem()))
+			target.Elem().Set(src.Convert(targetType.Elem()))
+		} else {
+			target.Set(src.Addr().Convert(targetType))
+		}
+	} else if targetType.Kind() == reflect.Slice {
+		l := target.Len()
+		newL := l + src.Len()
+		if target.Cap() < newL {
+			// expand capacity of the slice and copy
+			newSl := reflect.MakeSlice(targetType, newL, newL)
+			for i := 0; i < target.Len(); i++ {
+				newSl.Index(i).Set(target.Index(i))
+			}
+			target.Set(newSl)
+		} else {
+			target.SetLen(newL)
+		}
+		for i := 0; i < src.Len(); i++ {
+			dest := target.Index(l + i)
+			if dest.Kind() == reflect.Ptr {
+				dest.Set(reflect.New(dest.Type().Elem()))
+			}
+			if err := mergeVal(src.Index(i), dest, deterministic); err != nil {
+				return err
+			}
+		}
+	} else if targetType.Kind() == reflect.Map {
+		return mergeMapVal(src, target, targetType, deterministic)
+	} else if srcType == typeOfDynamicMessage && targetType.Implements(typeOfProtoMessage) {
+		dm := src.Interface().(*Message)
+		if target.IsNil() {
+			target.Set(reflect.New(targetType.Elem()))
+		}
+		m := target.Interface().(proto.Message)
+		if err := dm.mergeInto(m, deterministic); err != nil {
+			return err
+		}
+	} else {
+		return fmt.Errorf("cannot convert %v to %v", srcType, targetType)
+	}
+	return nil
+}
+
+func (m *Message) mergeFrom(pm proto.Message) error {
+	if dm, ok := pm.(*Message); ok {
+		// if given message is also a dynamic message, we merge differently
+		for tag, v := range dm.values {
+			fd := m.FindFieldDescriptor(tag)
+			if fd == nil {
+				fd = dm.FindFieldDescriptor(tag)
+			}
+			if err := mergeField(m, fd, v); err != nil {
+				return err
+			}
+		}
+		return nil
+	}
+
+	pmrv := reflect.ValueOf(pm)
+	if pmrv.IsNil() {
+		// nil is an empty message, so nothing to do
+		return nil
+	}
+
+	// check that we can successfully do the merge
+	src := pmrv.Elem()
+	values := map[*desc.FieldDescriptor]interface{}{}
+	props := proto.GetProperties(reflect.TypeOf(pm).Elem())
+	if props == nil {
+		return fmt.Errorf("could not determine message properties to merge for %v", reflect.TypeOf(pm).Elem())
+	}
+
+	// regular fields
+	for _, prop := range props.Prop {
+		if prop.Tag == 0 {
+			continue // one-of or special field (such as XXX_unrecognized, etc.)
+		}
+		fd := m.FindFieldDescriptor(int32(prop.Tag))
+		if fd == nil {
+			// Our descriptor has different fields than this message object. So
+			// try to reflect on the message object's fields.
+			md, err := desc.LoadMessageDescriptorForMessage(pm)
+			if err != nil {
+				return err
+			}
+			fd = md.FindFieldByNumber(int32(prop.Tag))
+			if fd == nil {
+				return fmt.Errorf("message descriptor %q did not contain field for tag %d (%q)", md.GetFullyQualifiedName(), prop.Tag, prop.Name)
+			}
+		}
+		rv := src.FieldByName(prop.Name)
+		if (rv.Kind() == reflect.Ptr || rv.Kind() == reflect.Slice) && rv.IsNil() {
+			continue
+		}
+		if v, err := validFieldValueForRv(fd, rv); err != nil {
+			return err
+		} else {
+			values[fd] = v
+		}
+	}
+
+	// one-of fields
+	for _, oop := range props.OneofTypes {
+		oov := src.Field(oop.Field).Elem()
+		if !oov.IsValid() || oov.Type() != oop.Type {
+			// this field is unset (in other words, one-of message field is not currently set to this option)
+			continue
+		}
+		prop := oop.Prop
+		rv := oov.Elem().FieldByName(prop.Name)
+		fd := m.FindFieldDescriptor(int32(prop.Tag))
+		if fd == nil {
+			// Our descriptor has different fields than this message object. So
+			// try to reflect on the message object's fields.
+			md, err := desc.LoadMessageDescriptorForMessage(pm)
+			if err != nil {
+				return err
+			}
+			fd = md.FindFieldByNumber(int32(prop.Tag))
+			if fd == nil {
+				return fmt.Errorf("message descriptor %q did not contain field for tag %d (%q in one-of %q)", md.GetFullyQualifiedName(), prop.Tag, prop.Name, src.Type().Field(oop.Field).Name)
+			}
+		}
+		if v, err := validFieldValueForRv(fd, rv); err != nil {
+			return err
+		} else {
+			values[fd] = v
+		}
+	}
+
+	// extension fields
+	rexts, _ := proto.ExtensionDescs(pm)
+	for _, ed := range rexts {
+		v, _ := proto.GetExtension(pm, ed)
+		if v == nil {
+			continue
+		}
+		if ed.ExtensionType == nil {
+			// unrecognized extension: we'll handle that below when we
+			// handle other unrecognized fields
+			continue
+		}
+		fd := m.er.FindExtension(m.md.GetFullyQualifiedName(), ed.Field)
+		if fd == nil {
+			var err error
+			if fd, err = desc.LoadFieldDescriptorForExtension(ed); err != nil {
+				return err
+			}
+		}
+		if v, err := validFieldValue(fd, v); err != nil {
+			return err
+		} else {
+			values[fd] = v
+		}
+	}
+
+	// now actually perform the merge
+	for fd, v := range values {
+		if err := mergeField(m, fd, v); err != nil {
+			return err
+		}
+	}
+
+	data := internal.GetUnrecognized(pm)
+	if len(data) > 0 {
+		// ignore any error returned: pulling in unknown fields is best-effort
+		_ = m.UnmarshalMerge(data)
+	}
+
+	return nil
+}
+
+// Validate checks that all required fields are present. It returns an error if any are absent.
+func (m *Message) Validate() error {
+	missingFields := m.findMissingFields()
+	if len(missingFields) == 0 {
+		return nil
+	}
+	return fmt.Errorf("some required fields missing: %v", strings.Join(missingFields, ", "))
+}
+
+func (m *Message) findMissingFields() []string {
+	if m.md.IsProto3() {
+		// proto3 does not allow required fields
+		return nil
+	}
+	var missingFields []string
+	for _, fd := range m.md.GetFields() {
+		if fd.IsRequired() {
+			if _, ok := m.values[fd.GetNumber()]; !ok {
+				missingFields = append(missingFields, fd.GetName())
+			}
+		}
+	}
+	return missingFields
+}
+
+// ValidateRecursive checks that all required fields are present and also
+// recursively validates all fields who are also messages. It returns an error
+// if any required fields, in this message or nested within, are absent.
+func (m *Message) ValidateRecursive() error {
+	return m.validateRecursive("")
+}
+
+func (m *Message) validateRecursive(prefix string) error {
+	if missingFields := m.findMissingFields(); len(missingFields) > 0 {
+		for i := range missingFields {
+			missingFields[i] = fmt.Sprintf("%s%s", prefix, missingFields[i])
+		}
+		return fmt.Errorf("some required fields missing: %v", strings.Join(missingFields, ", "))
+	}
+
+	for tag, fld := range m.values {
+		fd := m.FindFieldDescriptor(tag)
+		var chprefix string
+		var md *desc.MessageDescriptor
+		checkMsg := func(pm proto.Message) error {
+			var dm *Message
+			if d, ok := pm.(*Message); ok {
+				dm = d
+			} else if pm != nil {
+				dm = m.mf.NewDynamicMessage(md)
+				if err := dm.ConvertFrom(pm); err != nil {
+					return nil
+				}
+			}
+			if dm == nil {
+				return nil
+			}
+			if err := dm.validateRecursive(chprefix); err != nil {
+				return err
+			}
+			return nil
+		}
+		isMap := fd.IsMap()
+		if isMap && fd.GetMapValueType().GetMessageType() != nil {
+			md = fd.GetMapValueType().GetMessageType()
+			mp := fld.(map[interface{}]interface{})
+			for k, v := range mp {
+				chprefix = fmt.Sprintf("%s%s[%v].", prefix, getName(fd), k)
+				if err := checkMsg(v.(proto.Message)); err != nil {
+					return err
+				}
+			}
+		} else if !isMap && fd.GetMessageType() != nil {
+			md = fd.GetMessageType()
+			if fd.IsRepeated() {
+				sl := fld.([]interface{})
+				for i, v := range sl {
+					chprefix = fmt.Sprintf("%s%s[%d].", prefix, getName(fd), i)
+					if err := checkMsg(v.(proto.Message)); err != nil {
+						return err
+					}
+				}
+			} else {
+				chprefix = fmt.Sprintf("%s%s.", prefix, getName(fd))
+				if err := checkMsg(fld.(proto.Message)); err != nil {
+					return err
+				}
+			}
+		}
+	}
+
+	return nil
+}
+
+func getName(fd *desc.FieldDescriptor) string {
+	if fd.IsExtension() {
+		return fmt.Sprintf("(%s)", fd.GetFullyQualifiedName())
+	} else {
+		return fd.GetName()
+	}
+}
+
+// knownFieldTags return tags of present and recognized fields, in sorted order.
+func (m *Message) knownFieldTags() []int {
+	if len(m.values) == 0 {
+		return []int(nil)
+	}
+
+	keys := make([]int, len(m.values))
+	i := 0
+	for k := range m.values {
+		keys[i] = int(k)
+		i++
+	}
+
+	sort.Ints(keys)
+	return keys
+}
+
+// allKnownFieldTags return tags of present and recognized fields, including
+// those that are unset, in sorted order. This only includes extensions that are
+// present. Known but not-present extensions are not included in the returned
+// set of tags.
+func (m *Message) allKnownFieldTags() []int {
+	fds := m.md.GetFields()
+	keys := make([]int, 0, len(fds)+len(m.extraFields))
+
+	for k := range m.values {
+		keys = append(keys, int(k))
+	}
+
+	// also include known fields that are not present
+	for _, fd := range fds {
+		if _, ok := m.values[fd.GetNumber()]; !ok {
+			keys = append(keys, int(fd.GetNumber()))
+		}
+	}
+	for _, fd := range m.extraFields {
+		if !fd.IsExtension() { // skip extensions that are not present
+			if _, ok := m.values[fd.GetNumber()]; !ok {
+				keys = append(keys, int(fd.GetNumber()))
+			}
+		}
+	}
+
+	sort.Ints(keys)
+	return keys
+}
+
+// unknownFieldTags return tags of present but unrecognized fields, in sorted order.
+func (m *Message) unknownFieldTags() []int {
+	if len(m.unknownFields) == 0 {
+		return []int(nil)
+	}
+	keys := make([]int, len(m.unknownFields))
+	i := 0
+	for k := range m.unknownFields {
+		keys[i] = int(k)
+		i++
+	}
+	sort.Ints(keys)
+	return keys
+}