rebase: vendor dependencies for Vault API

Uses github.com/libopenstorage/secrets to communicate with Vault. This
removes the need for maintaining our own limited Vault APIs.

By adding the new dependency, several other packages got updated in the
process. Unused indirect dependencies have been removed from go.mod.

Signed-off-by: Niels de Vos <ndevos@redhat.com>

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

@@ -0,0 +1,177 @@
+// Copyright 2018 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package impl
+
+import (
+	"fmt"
+	"reflect"
+	"strconv"
+
+	"google.golang.org/protobuf/encoding/prototext"
+	"google.golang.org/protobuf/internal/errors"
+	"google.golang.org/protobuf/proto"
+	pref "google.golang.org/protobuf/reflect/protoreflect"
+	piface "google.golang.org/protobuf/runtime/protoiface"
+)
+
+// Export is a zero-length named type that exists only to export a set of
+// functions that we do not want to appear in godoc.
+type Export struct{}
+
+// NewError formats a string according to the format specifier and arguments and
+// returns an error that has a "proto" prefix.
+func (Export) NewError(f string, x ...interface{}) error {
+	return errors.New(f, x...)
+}
+
+// enum is any enum type generated by protoc-gen-go
+// and must be a named int32 type.
+type enum = interface{}
+
+// EnumOf returns the protoreflect.Enum interface over e.
+// It returns nil if e is nil.
+func (Export) EnumOf(e enum) pref.Enum {
+	switch e := e.(type) {
+	case nil:
+		return nil
+	case pref.Enum:
+		return e
+	default:
+		return legacyWrapEnum(reflect.ValueOf(e))
+	}
+}
+
+// EnumDescriptorOf returns the protoreflect.EnumDescriptor for e.
+// It returns nil if e is nil.
+func (Export) EnumDescriptorOf(e enum) pref.EnumDescriptor {
+	switch e := e.(type) {
+	case nil:
+		return nil
+	case pref.Enum:
+		return e.Descriptor()
+	default:
+		return LegacyLoadEnumDesc(reflect.TypeOf(e))
+	}
+}
+
+// EnumTypeOf returns the protoreflect.EnumType for e.
+// It returns nil if e is nil.
+func (Export) EnumTypeOf(e enum) pref.EnumType {
+	switch e := e.(type) {
+	case nil:
+		return nil
+	case pref.Enum:
+		return e.Type()
+	default:
+		return legacyLoadEnumType(reflect.TypeOf(e))
+	}
+}
+
+// EnumStringOf returns the enum value as a string, either as the name if
+// the number is resolvable, or the number formatted as a string.
+func (Export) EnumStringOf(ed pref.EnumDescriptor, n pref.EnumNumber) string {
+	ev := ed.Values().ByNumber(n)
+	if ev != nil {
+		return string(ev.Name())
+	}
+	return strconv.Itoa(int(n))
+}
+
+// message is any message type generated by protoc-gen-go
+// and must be a pointer to a named struct type.
+type message = interface{}
+
+// legacyMessageWrapper wraps a v2 message as a v1 message.
+type legacyMessageWrapper struct{ m pref.ProtoMessage }
+
+func (m legacyMessageWrapper) Reset()         { proto.Reset(m.m) }
+func (m legacyMessageWrapper) String() string { return Export{}.MessageStringOf(m.m) }
+func (m legacyMessageWrapper) ProtoMessage()  {}
+
+// ProtoMessageV1Of converts either a v1 or v2 message to a v1 message.
+// It returns nil if m is nil.
+func (Export) ProtoMessageV1Of(m message) piface.MessageV1 {
+	switch mv := m.(type) {
+	case nil:
+		return nil
+	case piface.MessageV1:
+		return mv
+	case unwrapper:
+		return Export{}.ProtoMessageV1Of(mv.protoUnwrap())
+	case pref.ProtoMessage:
+		return legacyMessageWrapper{mv}
+	default:
+		panic(fmt.Sprintf("message %T is neither a v1 or v2 Message", m))
+	}
+}
+
+func (Export) protoMessageV2Of(m message) pref.ProtoMessage {
+	switch mv := m.(type) {
+	case nil:
+		return nil
+	case pref.ProtoMessage:
+		return mv
+	case legacyMessageWrapper:
+		return mv.m
+	case piface.MessageV1:
+		return nil
+	default:
+		panic(fmt.Sprintf("message %T is neither a v1 or v2 Message", m))
+	}
+}
+
+// ProtoMessageV2Of converts either a v1 or v2 message to a v2 message.
+// It returns nil if m is nil.
+func (Export) ProtoMessageV2Of(m message) pref.ProtoMessage {
+	if m == nil {
+		return nil
+	}
+	if mv := (Export{}).protoMessageV2Of(m); mv != nil {
+		return mv
+	}
+	return legacyWrapMessage(reflect.ValueOf(m)).Interface()
+}
+
+// MessageOf returns the protoreflect.Message interface over m.
+// It returns nil if m is nil.
+func (Export) MessageOf(m message) pref.Message {
+	if m == nil {
+		return nil
+	}
+	if mv := (Export{}).protoMessageV2Of(m); mv != nil {
+		return mv.ProtoReflect()
+	}
+	return legacyWrapMessage(reflect.ValueOf(m))
+}
+
+// MessageDescriptorOf returns the protoreflect.MessageDescriptor for m.
+// It returns nil if m is nil.
+func (Export) MessageDescriptorOf(m message) pref.MessageDescriptor {
+	if m == nil {
+		return nil
+	}
+	if mv := (Export{}).protoMessageV2Of(m); mv != nil {
+		return mv.ProtoReflect().Descriptor()
+	}
+	return LegacyLoadMessageDesc(reflect.TypeOf(m))
+}
+
+// MessageTypeOf returns the protoreflect.MessageType for m.
+// It returns nil if m is nil.
+func (Export) MessageTypeOf(m message) pref.MessageType {
+	if m == nil {
+		return nil
+	}
+	if mv := (Export{}).protoMessageV2Of(m); mv != nil {
+		return mv.ProtoReflect().Type()
+	}
+	return legacyLoadMessageInfo(reflect.TypeOf(m), "")
+}
+
+// MessageStringOf returns the message value as a string,
+// which is the message serialized in the protobuf text format.
+func (Export) MessageStringOf(m pref.ProtoMessage) string {
+	return prototext.MarshalOptions{Multiline: false}.Format(m)
+}

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

@@ -0,0 +1,141 @@
+// Copyright 2019 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package impl
+
+import (
+	"sync"
+
+	"google.golang.org/protobuf/internal/errors"
+	pref "google.golang.org/protobuf/reflect/protoreflect"
+	piface "google.golang.org/protobuf/runtime/protoiface"
+)
+
+func (mi *MessageInfo) checkInitialized(in piface.CheckInitializedInput) (piface.CheckInitializedOutput, error) {
+	var p pointer
+	if ms, ok := in.Message.(*messageState); ok {
+		p = ms.pointer()
+	} else {
+		p = in.Message.(*messageReflectWrapper).pointer()
+	}
+	return piface.CheckInitializedOutput{}, mi.checkInitializedPointer(p)
+}
+
+func (mi *MessageInfo) checkInitializedPointer(p pointer) error {
+	mi.init()
+	if !mi.needsInitCheck {
+		return nil
+	}
+	if p.IsNil() {
+		for _, f := range mi.orderedCoderFields {
+			if f.isRequired {
+				return errors.RequiredNotSet(string(mi.Desc.Fields().ByNumber(f.num).FullName()))
+			}
+		}
+		return nil
+	}
+	if mi.extensionOffset.IsValid() {
+		e := p.Apply(mi.extensionOffset).Extensions()
+		if err := mi.isInitExtensions(e); err != nil {
+			return err
+		}
+	}
+	for _, f := range mi.orderedCoderFields {
+		if !f.isRequired && f.funcs.isInit == nil {
+			continue
+		}
+		fptr := p.Apply(f.offset)
+		if f.isPointer && fptr.Elem().IsNil() {
+			if f.isRequired {
+				return errors.RequiredNotSet(string(mi.Desc.Fields().ByNumber(f.num).FullName()))
+			}
+			continue
+		}
+		if f.funcs.isInit == nil {
+			continue
+		}
+		if err := f.funcs.isInit(fptr, f); err != nil {
+			return err
+		}
+	}
+	return nil
+}
+
+func (mi *MessageInfo) isInitExtensions(ext *map[int32]ExtensionField) error {
+	if ext == nil {
+		return nil
+	}
+	for _, x := range *ext {
+		ei := getExtensionFieldInfo(x.Type())
+		if ei.funcs.isInit == nil {
+			continue
+		}
+		v := x.Value()
+		if !v.IsValid() {
+			continue
+		}
+		if err := ei.funcs.isInit(v); err != nil {
+			return err
+		}
+	}
+	return nil
+}
+
+var (
+	needsInitCheckMu  sync.Mutex
+	needsInitCheckMap sync.Map
+)
+
+// needsInitCheck reports whether a message needs to be checked for partial initialization.
+//
+// It returns true if the message transitively includes any required or extension fields.
+func needsInitCheck(md pref.MessageDescriptor) bool {
+	if v, ok := needsInitCheckMap.Load(md); ok {
+		if has, ok := v.(bool); ok {
+			return has
+		}
+	}
+	needsInitCheckMu.Lock()
+	defer needsInitCheckMu.Unlock()
+	return needsInitCheckLocked(md)
+}
+
+func needsInitCheckLocked(md pref.MessageDescriptor) (has bool) {
+	if v, ok := needsInitCheckMap.Load(md); ok {
+		// If has is true, we've previously determined that this message
+		// needs init checks.
+		//
+		// If has is false, we've previously determined that it can never
+		// be uninitialized.
+		//
+		// If has is not a bool, we've just encountered a cycle in the
+		// message graph. In this case, it is safe to return false: If
+		// the message does have required fields, we'll detect them later
+		// in the graph traversal.
+		has, ok := v.(bool)
+		return ok && has
+	}
+	needsInitCheckMap.Store(md, struct{}{}) // avoid cycles while descending into this message
+	defer func() {
+		needsInitCheckMap.Store(md, has)
+	}()
+	if md.RequiredNumbers().Len() > 0 {
+		return true
+	}
+	if md.ExtensionRanges().Len() > 0 {
+		return true
+	}
+	for i := 0; i < md.Fields().Len(); i++ {
+		fd := md.Fields().Get(i)
+		// Map keys are never messages, so just consider the map value.
+		if fd.IsMap() {
+			fd = fd.MapValue()
+		}
+		fmd := fd.Message()
+		if fmd != nil && needsInitCheckLocked(fmd) {
+			return true
+		}
+	}
+	return false
+}

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

@@ -0,0 +1,223 @@
+// Copyright 2019 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package impl
+
+import (
+	"sync"
+	"sync/atomic"
+
+	"google.golang.org/protobuf/encoding/protowire"
+	"google.golang.org/protobuf/internal/errors"
+	pref "google.golang.org/protobuf/reflect/protoreflect"
+)
+
+type extensionFieldInfo struct {
+	wiretag             uint64
+	tagsize             int
+	unmarshalNeedsValue bool
+	funcs               valueCoderFuncs
+	validation          validationInfo
+}
+
+var legacyExtensionFieldInfoCache sync.Map // map[protoreflect.ExtensionType]*extensionFieldInfo
+
+func getExtensionFieldInfo(xt pref.ExtensionType) *extensionFieldInfo {
+	if xi, ok := xt.(*ExtensionInfo); ok {
+		xi.lazyInit()
+		return xi.info
+	}
+	return legacyLoadExtensionFieldInfo(xt)
+}
+
+// legacyLoadExtensionFieldInfo dynamically loads a *ExtensionInfo for xt.
+func legacyLoadExtensionFieldInfo(xt pref.ExtensionType) *extensionFieldInfo {
+	if xi, ok := legacyExtensionFieldInfoCache.Load(xt); ok {
+		return xi.(*extensionFieldInfo)
+	}
+	e := makeExtensionFieldInfo(xt.TypeDescriptor())
+	if e, ok := legacyMessageTypeCache.LoadOrStore(xt, e); ok {
+		return e.(*extensionFieldInfo)
+	}
+	return e
+}
+
+func makeExtensionFieldInfo(xd pref.ExtensionDescriptor) *extensionFieldInfo {
+	var wiretag uint64
+	if !xd.IsPacked() {
+		wiretag = protowire.EncodeTag(xd.Number(), wireTypes[xd.Kind()])
+	} else {
+		wiretag = protowire.EncodeTag(xd.Number(), protowire.BytesType)
+	}
+	e := &extensionFieldInfo{
+		wiretag: wiretag,
+		tagsize: protowire.SizeVarint(wiretag),
+		funcs:   encoderFuncsForValue(xd),
+	}
+	// Does the unmarshal function need a value passed to it?
+	// This is true for composite types, where we pass in a message, list, or map to fill in,
+	// and for enums, where we pass in a prototype value to specify the concrete enum type.
+	switch xd.Kind() {
+	case pref.MessageKind, pref.GroupKind, pref.EnumKind:
+		e.unmarshalNeedsValue = true
+	default:
+		if xd.Cardinality() == pref.Repeated {
+			e.unmarshalNeedsValue = true
+		}
+	}
+	return e
+}
+
+type lazyExtensionValue struct {
+	atomicOnce uint32 // atomically set if value is valid
+	mu         sync.Mutex
+	xi         *extensionFieldInfo
+	value      pref.Value
+	b          []byte
+	fn         func() pref.Value
+}
+
+type ExtensionField struct {
+	typ pref.ExtensionType
+
+	// value is either the value of GetValue,
+	// or a *lazyExtensionValue that then returns the value of GetValue.
+	value pref.Value
+	lazy  *lazyExtensionValue
+}
+
+func (f *ExtensionField) appendLazyBytes(xt pref.ExtensionType, xi *extensionFieldInfo, num protowire.Number, wtyp protowire.Type, b []byte) {
+	if f.lazy == nil {
+		f.lazy = &lazyExtensionValue{xi: xi}
+	}
+	f.typ = xt
+	f.lazy.xi = xi
+	f.lazy.b = protowire.AppendTag(f.lazy.b, num, wtyp)
+	f.lazy.b = append(f.lazy.b, b...)
+}
+
+func (f *ExtensionField) canLazy(xt pref.ExtensionType) bool {
+	if f.typ == nil {
+		return true
+	}
+	if f.typ == xt && f.lazy != nil && atomic.LoadUint32(&f.lazy.atomicOnce) == 0 {
+		return true
+	}
+	return false
+}
+
+func (f *ExtensionField) lazyInit() {
+	f.lazy.mu.Lock()
+	defer f.lazy.mu.Unlock()
+	if atomic.LoadUint32(&f.lazy.atomicOnce) == 1 {
+		return
+	}
+	if f.lazy.xi != nil {
+		b := f.lazy.b
+		val := f.typ.New()
+		for len(b) > 0 {
+			var tag uint64
+			if b[0] < 0x80 {
+				tag = uint64(b[0])
+				b = b[1:]
+			} else if len(b) >= 2 && b[1] < 128 {
+				tag = uint64(b[0]&0x7f) + uint64(b[1])<<7
+				b = b[2:]
+			} else {
+				var n int
+				tag, n = protowire.ConsumeVarint(b)
+				if n < 0 {
+					panic(errors.New("bad tag in lazy extension decoding"))
+				}
+				b = b[n:]
+			}
+			num := protowire.Number(tag >> 3)
+			wtyp := protowire.Type(tag & 7)
+			var out unmarshalOutput
+			var err error
+			val, out, err = f.lazy.xi.funcs.unmarshal(b, val, num, wtyp, lazyUnmarshalOptions)
+			if err != nil {
+				panic(errors.New("decode failure in lazy extension decoding: %v", err))
+			}
+			b = b[out.n:]
+		}
+		f.lazy.value = val
+	} else {
+		f.lazy.value = f.lazy.fn()
+	}
+	f.lazy.xi = nil
+	f.lazy.fn = nil
+	f.lazy.b = nil
+	atomic.StoreUint32(&f.lazy.atomicOnce, 1)
+}
+
+// Set sets the type and value of the extension field.
+// This must not be called concurrently.
+func (f *ExtensionField) Set(t pref.ExtensionType, v pref.Value) {
+	f.typ = t
+	f.value = v
+	f.lazy = nil
+}
+
+// SetLazy sets the type and a value that is to be lazily evaluated upon first use.
+// This must not be called concurrently.
+func (f *ExtensionField) SetLazy(t pref.ExtensionType, fn func() pref.Value) {
+	f.typ = t
+	f.lazy = &lazyExtensionValue{fn: fn}
+}
+
+// Value returns the value of the extension field.
+// This may be called concurrently.
+func (f *ExtensionField) Value() pref.Value {
+	if f.lazy != nil {
+		if atomic.LoadUint32(&f.lazy.atomicOnce) == 0 {
+			f.lazyInit()
+		}
+		return f.lazy.value
+	}
+	return f.value
+}
+
+// Type returns the type of the extension field.
+// This may be called concurrently.
+func (f ExtensionField) Type() pref.ExtensionType {
+	return f.typ
+}
+
+// IsSet returns whether the extension field is set.
+// This may be called concurrently.
+func (f ExtensionField) IsSet() bool {
+	return f.typ != nil
+}
+
+// IsLazy reports whether a field is lazily encoded.
+// It is exported for testing.
+func IsLazy(m pref.Message, fd pref.FieldDescriptor) bool {
+	var mi *MessageInfo
+	var p pointer
+	switch m := m.(type) {
+	case *messageState:
+		mi = m.messageInfo()
+		p = m.pointer()
+	case *messageReflectWrapper:
+		mi = m.messageInfo()
+		p = m.pointer()
+	default:
+		return false
+	}
+	xd, ok := fd.(pref.ExtensionTypeDescriptor)
+	if !ok {
+		return false
+	}
+	xt := xd.Type()
+	ext := mi.extensionMap(p)
+	if ext == nil {
+		return false
+	}
+	f, ok := (*ext)[int32(fd.Number())]
+	if !ok {
+		return false
+	}
+	return f.typ == xt && f.lazy != nil && atomic.LoadUint32(&f.lazy.atomicOnce) == 0
+}

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

@@ -0,0 +1,828 @@
+// Copyright 2019 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package impl
+
+import (
+	"fmt"
+	"reflect"
+	"sync"
+
+	"google.golang.org/protobuf/encoding/protowire"
+	"google.golang.org/protobuf/proto"
+	pref "google.golang.org/protobuf/reflect/protoreflect"
+	preg "google.golang.org/protobuf/reflect/protoregistry"
+	piface "google.golang.org/protobuf/runtime/protoiface"
+)
+
+type errInvalidUTF8 struct{}
+
+func (errInvalidUTF8) Error() string     { return "string field contains invalid UTF-8" }
+func (errInvalidUTF8) InvalidUTF8() bool { return true }
+
+// initOneofFieldCoders initializes the fast-path functions for the fields in a oneof.
+//
+// For size, marshal, and isInit operations, functions are set only on the first field
+// in the oneof. The functions are called when the oneof is non-nil, and will dispatch
+// to the appropriate field-specific function as necessary.
+//
+// The unmarshal function is set on each field individually as usual.
+func (mi *MessageInfo) initOneofFieldCoders(od pref.OneofDescriptor, si structInfo) {
+	fs := si.oneofsByName[od.Name()]
+	ft := fs.Type
+	oneofFields := make(map[reflect.Type]*coderFieldInfo)
+	needIsInit := false
+	fields := od.Fields()
+	for i, lim := 0, fields.Len(); i < lim; i++ {
+		fd := od.Fields().Get(i)
+		num := fd.Number()
+		// Make a copy of the original coderFieldInfo for use in unmarshaling.
+		//
+		// oneofFields[oneofType].funcs.marshal is the field-specific marshal function.
+		//
+		// mi.coderFields[num].marshal is set on only the first field in the oneof,
+		// and dispatches to the field-specific marshaler in oneofFields.
+		cf := *mi.coderFields[num]
+		ot := si.oneofWrappersByNumber[num]
+		cf.ft = ot.Field(0).Type
+		cf.mi, cf.funcs = fieldCoder(fd, cf.ft)
+		oneofFields[ot] = &cf
+		if cf.funcs.isInit != nil {
+			needIsInit = true
+		}
+		mi.coderFields[num].funcs.unmarshal = func(b []byte, p pointer, wtyp protowire.Type, f *coderFieldInfo, opts unmarshalOptions) (unmarshalOutput, error) {
+			var vw reflect.Value         // pointer to wrapper type
+			vi := p.AsValueOf(ft).Elem() // oneof field value of interface kind
+			if !vi.IsNil() && !vi.Elem().IsNil() && vi.Elem().Elem().Type() == ot {
+				vw = vi.Elem()
+			} else {
+				vw = reflect.New(ot)
+			}
+			out, err := cf.funcs.unmarshal(b, pointerOfValue(vw).Apply(zeroOffset), wtyp, &cf, opts)
+			if err != nil {
+				return out, err
+			}
+			vi.Set(vw)
+			return out, nil
+		}
+	}
+	getInfo := func(p pointer) (pointer, *coderFieldInfo) {
+		v := p.AsValueOf(ft).Elem()
+		if v.IsNil() {
+			return pointer{}, nil
+		}
+		v = v.Elem() // interface -> *struct
+		if v.IsNil() {
+			return pointer{}, nil
+		}
+		return pointerOfValue(v).Apply(zeroOffset), oneofFields[v.Elem().Type()]
+	}
+	first := mi.coderFields[od.Fields().Get(0).Number()]
+	first.funcs.size = func(p pointer, _ *coderFieldInfo, opts marshalOptions) int {
+		p, info := getInfo(p)
+		if info == nil || info.funcs.size == nil {
+			return 0
+		}
+		return info.funcs.size(p, info, opts)
+	}
+	first.funcs.marshal = func(b []byte, p pointer, _ *coderFieldInfo, opts marshalOptions) ([]byte, error) {
+		p, info := getInfo(p)
+		if info == nil || info.funcs.marshal == nil {
+			return b, nil
+		}
+		return info.funcs.marshal(b, p, info, opts)
+	}
+	first.funcs.merge = func(dst, src pointer, _ *coderFieldInfo, opts mergeOptions) {
+		srcp, srcinfo := getInfo(src)
+		if srcinfo == nil || srcinfo.funcs.merge == nil {
+			return
+		}
+		dstp, dstinfo := getInfo(dst)
+		if dstinfo != srcinfo {
+			dst.AsValueOf(ft).Elem().Set(reflect.New(src.AsValueOf(ft).Elem().Elem().Elem().Type()))
+			dstp = pointerOfValue(dst.AsValueOf(ft).Elem().Elem()).Apply(zeroOffset)
+		}
+		srcinfo.funcs.merge(dstp, srcp, srcinfo, opts)
+	}
+	if needIsInit {
+		first.funcs.isInit = func(p pointer, _ *coderFieldInfo) error {
+			p, info := getInfo(p)
+			if info == nil || info.funcs.isInit == nil {
+				return nil
+			}
+			return info.funcs.isInit(p, info)
+		}
+	}
+}
+
+func makeWeakMessageFieldCoder(fd pref.FieldDescriptor) pointerCoderFuncs {
+	var once sync.Once
+	var messageType pref.MessageType
+	lazyInit := func() {
+		once.Do(func() {
+			messageName := fd.Message().FullName()
+			messageType, _ = preg.GlobalTypes.FindMessageByName(messageName)
+		})
+	}
+
+	return pointerCoderFuncs{
+		size: func(p pointer, f *coderFieldInfo, opts marshalOptions) int {
+			m, ok := p.WeakFields().get(f.num)
+			if !ok {
+				return 0
+			}
+			lazyInit()
+			if messageType == nil {
+				panic(fmt.Sprintf("weak message %v is not linked in", fd.Message().FullName()))
+			}
+			return sizeMessage(m, f.tagsize, opts)
+		},
+		marshal: func(b []byte, p pointer, f *coderFieldInfo, opts marshalOptions) ([]byte, error) {
+			m, ok := p.WeakFields().get(f.num)
+			if !ok {
+				return b, nil
+			}
+			lazyInit()
+			if messageType == nil {
+				panic(fmt.Sprintf("weak message %v is not linked in", fd.Message().FullName()))
+			}
+			return appendMessage(b, m, f.wiretag, opts)
+		},
+		unmarshal: func(b []byte, p pointer, wtyp protowire.Type, f *coderFieldInfo, opts unmarshalOptions) (unmarshalOutput, error) {
+			fs := p.WeakFields()
+			m, ok := fs.get(f.num)
+			if !ok {
+				lazyInit()
+				if messageType == nil {
+					return unmarshalOutput{}, errUnknown
+				}
+				m = messageType.New().Interface()
+				fs.set(f.num, m)
+			}
+			return consumeMessage(b, m, wtyp, opts)
+		},
+		isInit: func(p pointer, f *coderFieldInfo) error {
+			m, ok := p.WeakFields().get(f.num)
+			if !ok {
+				return nil
+			}
+			return proto.CheckInitialized(m)
+		},
+		merge: func(dst, src pointer, f *coderFieldInfo, opts mergeOptions) {
+			sm, ok := src.WeakFields().get(f.num)
+			if !ok {
+				return
+			}
+			dm, ok := dst.WeakFields().get(f.num)
+			if !ok {
+				lazyInit()
+				if messageType == nil {
+					panic(fmt.Sprintf("weak message %v is not linked in", fd.Message().FullName()))
+				}
+				dm = messageType.New().Interface()
+				dst.WeakFields().set(f.num, dm)
+			}
+			opts.Merge(dm, sm)
+		},
+	}
+}
+
+func makeMessageFieldCoder(fd pref.FieldDescriptor, ft reflect.Type) pointerCoderFuncs {
+	if mi := getMessageInfo(ft); mi != nil {
+		funcs := pointerCoderFuncs{
+			size:      sizeMessageInfo,
+			marshal:   appendMessageInfo,
+			unmarshal: consumeMessageInfo,
+			merge:     mergeMessage,
+		}
+		if needsInitCheck(mi.Desc) {
+			funcs.isInit = isInitMessageInfo
+		}
+		return funcs
+	} else {
+		return pointerCoderFuncs{
+			size: func(p pointer, f *coderFieldInfo, opts marshalOptions) int {
+				m := asMessage(p.AsValueOf(ft).Elem())
+				return sizeMessage(m, f.tagsize, opts)
+			},
+			marshal: func(b []byte, p pointer, f *coderFieldInfo, opts marshalOptions) ([]byte, error) {
+				m := asMessage(p.AsValueOf(ft).Elem())
+				return appendMessage(b, m, f.wiretag, opts)
+			},
+			unmarshal: func(b []byte, p pointer, wtyp protowire.Type, f *coderFieldInfo, opts unmarshalOptions) (unmarshalOutput, error) {
+				mp := p.AsValueOf(ft).Elem()
+				if mp.IsNil() {
+					mp.Set(reflect.New(ft.Elem()))
+				}
+				return consumeMessage(b, asMessage(mp), wtyp, opts)
+			},
+			isInit: func(p pointer, f *coderFieldInfo) error {
+				m := asMessage(p.AsValueOf(ft).Elem())
+				return proto.CheckInitialized(m)
+			},
+			merge: mergeMessage,
+		}
+	}
+}
+
+func sizeMessageInfo(p pointer, f *coderFieldInfo, opts marshalOptions) int {
+	return protowire.SizeBytes(f.mi.sizePointer(p.Elem(), opts)) + f.tagsize
+}
+
+func appendMessageInfo(b []byte, p pointer, f *coderFieldInfo, opts marshalOptions) ([]byte, error) {
+	b = protowire.AppendVarint(b, f.wiretag)
+	b = protowire.AppendVarint(b, uint64(f.mi.sizePointer(p.Elem(), opts)))
+	return f.mi.marshalAppendPointer(b, p.Elem(), opts)
+}
+
+func consumeMessageInfo(b []byte, p pointer, wtyp protowire.Type, f *coderFieldInfo, opts unmarshalOptions) (out unmarshalOutput, err error) {
+	if wtyp != protowire.BytesType {
+		return out, errUnknown
+	}
+	v, n := protowire.ConsumeBytes(b)
+	if n < 0 {
+		return out, protowire.ParseError(n)
+	}
+	if p.Elem().IsNil() {
+		p.SetPointer(pointerOfValue(reflect.New(f.mi.GoReflectType.Elem())))
+	}
+	o, err := f.mi.unmarshalPointer(v, p.Elem(), 0, opts)
+	if err != nil {
+		return out, err
+	}
+	out.n = n
+	out.initialized = o.initialized
+	return out, nil
+}
+
+func isInitMessageInfo(p pointer, f *coderFieldInfo) error {
+	return f.mi.checkInitializedPointer(p.Elem())
+}
+
+func sizeMessage(m proto.Message, tagsize int, _ marshalOptions) int {
+	return protowire.SizeBytes(proto.Size(m)) + tagsize
+}
+
+func appendMessage(b []byte, m proto.Message, wiretag uint64, opts marshalOptions) ([]byte, error) {
+	b = protowire.AppendVarint(b, wiretag)
+	b = protowire.AppendVarint(b, uint64(proto.Size(m)))
+	return opts.Options().MarshalAppend(b, m)
+}
+
+func consumeMessage(b []byte, m proto.Message, wtyp protowire.Type, opts unmarshalOptions) (out unmarshalOutput, err error) {
+	if wtyp != protowire.BytesType {
+		return out, errUnknown
+	}
+	v, n := protowire.ConsumeBytes(b)
+	if n < 0 {
+		return out, protowire.ParseError(n)
+	}
+	o, err := opts.Options().UnmarshalState(piface.UnmarshalInput{
+		Buf:     v,
+		Message: m.ProtoReflect(),
+	})
+	if err != nil {
+		return out, err
+	}
+	out.n = n
+	out.initialized = o.Flags&piface.UnmarshalInitialized != 0
+	return out, nil
+}
+
+func sizeMessageValue(v pref.Value, tagsize int, opts marshalOptions) int {
+	m := v.Message().Interface()
+	return sizeMessage(m, tagsize, opts)
+}
+
+func appendMessageValue(b []byte, v pref.Value, wiretag uint64, opts marshalOptions) ([]byte, error) {
+	m := v.Message().Interface()
+	return appendMessage(b, m, wiretag, opts)
+}
+
+func consumeMessageValue(b []byte, v pref.Value, _ protowire.Number, wtyp protowire.Type, opts unmarshalOptions) (pref.Value, unmarshalOutput, error) {
+	m := v.Message().Interface()
+	out, err := consumeMessage(b, m, wtyp, opts)
+	return v, out, err
+}
+
+func isInitMessageValue(v pref.Value) error {
+	m := v.Message().Interface()
+	return proto.CheckInitialized(m)
+}
+
+var coderMessageValue = valueCoderFuncs{
+	size:      sizeMessageValue,
+	marshal:   appendMessageValue,
+	unmarshal: consumeMessageValue,
+	isInit:    isInitMessageValue,
+	merge:     mergeMessageValue,
+}
+
+func sizeGroupValue(v pref.Value, tagsize int, opts marshalOptions) int {
+	m := v.Message().Interface()
+	return sizeGroup(m, tagsize, opts)
+}
+
+func appendGroupValue(b []byte, v pref.Value, wiretag uint64, opts marshalOptions) ([]byte, error) {
+	m := v.Message().Interface()
+	return appendGroup(b, m, wiretag, opts)
+}
+
+func consumeGroupValue(b []byte, v pref.Value, num protowire.Number, wtyp protowire.Type, opts unmarshalOptions) (pref.Value, unmarshalOutput, error) {
+	m := v.Message().Interface()
+	out, err := consumeGroup(b, m, num, wtyp, opts)
+	return v, out, err
+}
+
+var coderGroupValue = valueCoderFuncs{
+	size:      sizeGroupValue,
+	marshal:   appendGroupValue,
+	unmarshal: consumeGroupValue,
+	isInit:    isInitMessageValue,
+	merge:     mergeMessageValue,
+}
+
+func makeGroupFieldCoder(fd pref.FieldDescriptor, ft reflect.Type) pointerCoderFuncs {
+	num := fd.Number()
+	if mi := getMessageInfo(ft); mi != nil {
+		funcs := pointerCoderFuncs{
+			size:      sizeGroupType,
+			marshal:   appendGroupType,
+			unmarshal: consumeGroupType,
+			merge:     mergeMessage,
+		}
+		if needsInitCheck(mi.Desc) {
+			funcs.isInit = isInitMessageInfo
+		}
+		return funcs
+	} else {
+		return pointerCoderFuncs{
+			size: func(p pointer, f *coderFieldInfo, opts marshalOptions) int {
+				m := asMessage(p.AsValueOf(ft).Elem())
+				return sizeGroup(m, f.tagsize, opts)
+			},
+			marshal: func(b []byte, p pointer, f *coderFieldInfo, opts marshalOptions) ([]byte, error) {
+				m := asMessage(p.AsValueOf(ft).Elem())
+				return appendGroup(b, m, f.wiretag, opts)
+			},
+			unmarshal: func(b []byte, p pointer, wtyp protowire.Type, f *coderFieldInfo, opts unmarshalOptions) (unmarshalOutput, error) {
+				mp := p.AsValueOf(ft).Elem()
+				if mp.IsNil() {
+					mp.Set(reflect.New(ft.Elem()))
+				}
+				return consumeGroup(b, asMessage(mp), num, wtyp, opts)
+			},
+			isInit: func(p pointer, f *coderFieldInfo) error {
+				m := asMessage(p.AsValueOf(ft).Elem())
+				return proto.CheckInitialized(m)
+			},
+			merge: mergeMessage,
+		}
+	}
+}
+
+func sizeGroupType(p pointer, f *coderFieldInfo, opts marshalOptions) int {
+	return 2*f.tagsize + f.mi.sizePointer(p.Elem(), opts)
+}
+
+func appendGroupType(b []byte, p pointer, f *coderFieldInfo, opts marshalOptions) ([]byte, error) {
+	b = protowire.AppendVarint(b, f.wiretag) // start group
+	b, err := f.mi.marshalAppendPointer(b, p.Elem(), opts)
+	b = protowire.AppendVarint(b, f.wiretag+1) // end group
+	return b, err
+}
+
+func consumeGroupType(b []byte, p pointer, wtyp protowire.Type, f *coderFieldInfo, opts unmarshalOptions) (out unmarshalOutput, err error) {
+	if wtyp != protowire.StartGroupType {
+		return out, errUnknown
+	}
+	if p.Elem().IsNil() {
+		p.SetPointer(pointerOfValue(reflect.New(f.mi.GoReflectType.Elem())))
+	}
+	return f.mi.unmarshalPointer(b, p.Elem(), f.num, opts)
+}
+
+func sizeGroup(m proto.Message, tagsize int, _ marshalOptions) int {
+	return 2*tagsize + proto.Size(m)
+}
+
+func appendGroup(b []byte, m proto.Message, wiretag uint64, opts marshalOptions) ([]byte, error) {
+	b = protowire.AppendVarint(b, wiretag) // start group
+	b, err := opts.Options().MarshalAppend(b, m)
+	b = protowire.AppendVarint(b, wiretag+1) // end group
+	return b, err
+}
+
+func consumeGroup(b []byte, m proto.Message, num protowire.Number, wtyp protowire.Type, opts unmarshalOptions) (out unmarshalOutput, err error) {
+	if wtyp != protowire.StartGroupType {
+		return out, errUnknown
+	}
+	b, n := protowire.ConsumeGroup(num, b)
+	if n < 0 {
+		return out, protowire.ParseError(n)
+	}
+	o, err := opts.Options().UnmarshalState(piface.UnmarshalInput{
+		Buf:     b,
+		Message: m.ProtoReflect(),
+	})
+	if err != nil {
+		return out, err
+	}
+	out.n = n
+	out.initialized = o.Flags&piface.UnmarshalInitialized != 0
+	return out, nil
+}
+
+func makeMessageSliceFieldCoder(fd pref.FieldDescriptor, ft reflect.Type) pointerCoderFuncs {
+	if mi := getMessageInfo(ft); mi != nil {
+		funcs := pointerCoderFuncs{
+			size:      sizeMessageSliceInfo,
+			marshal:   appendMessageSliceInfo,
+			unmarshal: consumeMessageSliceInfo,
+			merge:     mergeMessageSlice,
+		}
+		if needsInitCheck(mi.Desc) {
+			funcs.isInit = isInitMessageSliceInfo
+		}
+		return funcs
+	}
+	return pointerCoderFuncs{
+		size: func(p pointer, f *coderFieldInfo, opts marshalOptions) int {
+			return sizeMessageSlice(p, ft, f.tagsize, opts)
+		},
+		marshal: func(b []byte, p pointer, f *coderFieldInfo, opts marshalOptions) ([]byte, error) {
+			return appendMessageSlice(b, p, f.wiretag, ft, opts)
+		},
+		unmarshal: func(b []byte, p pointer, wtyp protowire.Type, f *coderFieldInfo, opts unmarshalOptions) (unmarshalOutput, error) {
+			return consumeMessageSlice(b, p, ft, wtyp, opts)
+		},
+		isInit: func(p pointer, f *coderFieldInfo) error {
+			return isInitMessageSlice(p, ft)
+		},
+		merge: mergeMessageSlice,
+	}
+}
+
+func sizeMessageSliceInfo(p pointer, f *coderFieldInfo, opts marshalOptions) int {
+	s := p.PointerSlice()
+	n := 0
+	for _, v := range s {
+		n += protowire.SizeBytes(f.mi.sizePointer(v, opts)) + f.tagsize
+	}
+	return n
+}
+
+func appendMessageSliceInfo(b []byte, p pointer, f *coderFieldInfo, opts marshalOptions) ([]byte, error) {
+	s := p.PointerSlice()
+	var err error
+	for _, v := range s {
+		b = protowire.AppendVarint(b, f.wiretag)
+		siz := f.mi.sizePointer(v, opts)
+		b = protowire.AppendVarint(b, uint64(siz))
+		b, err = f.mi.marshalAppendPointer(b, v, opts)
+		if err != nil {
+			return b, err
+		}
+	}
+	return b, nil
+}
+
+func consumeMessageSliceInfo(b []byte, p pointer, wtyp protowire.Type, f *coderFieldInfo, opts unmarshalOptions) (out unmarshalOutput, err error) {
+	if wtyp != protowire.BytesType {
+		return out, errUnknown
+	}
+	v, n := protowire.ConsumeBytes(b)
+	if n < 0 {
+		return out, protowire.ParseError(n)
+	}
+	m := reflect.New(f.mi.GoReflectType.Elem()).Interface()
+	mp := pointerOfIface(m)
+	o, err := f.mi.unmarshalPointer(v, mp, 0, opts)
+	if err != nil {
+		return out, err
+	}
+	p.AppendPointerSlice(mp)
+	out.n = n
+	out.initialized = o.initialized
+	return out, nil
+}
+
+func isInitMessageSliceInfo(p pointer, f *coderFieldInfo) error {
+	s := p.PointerSlice()
+	for _, v := range s {
+		if err := f.mi.checkInitializedPointer(v); err != nil {
+			return err
+		}
+	}
+	return nil
+}
+
+func sizeMessageSlice(p pointer, goType reflect.Type, tagsize int, _ marshalOptions) int {
+	s := p.PointerSlice()
+	n := 0
+	for _, v := range s {
+		m := asMessage(v.AsValueOf(goType.Elem()))
+		n += protowire.SizeBytes(proto.Size(m)) + tagsize
+	}
+	return n
+}
+
+func appendMessageSlice(b []byte, p pointer, wiretag uint64, goType reflect.Type, opts marshalOptions) ([]byte, error) {
+	s := p.PointerSlice()
+	var err error
+	for _, v := range s {
+		m := asMessage(v.AsValueOf(goType.Elem()))
+		b = protowire.AppendVarint(b, wiretag)
+		siz := proto.Size(m)
+		b = protowire.AppendVarint(b, uint64(siz))
+		b, err = opts.Options().MarshalAppend(b, m)
+		if err != nil {
+			return b, err
+		}
+	}
+	return b, nil
+}
+
+func consumeMessageSlice(b []byte, p pointer, goType reflect.Type, wtyp protowire.Type, opts unmarshalOptions) (out unmarshalOutput, err error) {
+	if wtyp != protowire.BytesType {
+		return out, errUnknown
+	}
+	v, n := protowire.ConsumeBytes(b)
+	if n < 0 {
+		return out, protowire.ParseError(n)
+	}
+	mp := reflect.New(goType.Elem())
+	o, err := opts.Options().UnmarshalState(piface.UnmarshalInput{
+		Buf:     v,
+		Message: asMessage(mp).ProtoReflect(),
+	})
+	if err != nil {
+		return out, err
+	}
+	p.AppendPointerSlice(pointerOfValue(mp))
+	out.n = n
+	out.initialized = o.Flags&piface.UnmarshalInitialized != 0
+	return out, nil
+}
+
+func isInitMessageSlice(p pointer, goType reflect.Type) error {
+	s := p.PointerSlice()
+	for _, v := range s {
+		m := asMessage(v.AsValueOf(goType.Elem()))
+		if err := proto.CheckInitialized(m); err != nil {
+			return err
+		}
+	}
+	return nil
+}
+
+// Slices of messages
+
+func sizeMessageSliceValue(listv pref.Value, tagsize int, opts marshalOptions) int {
+	list := listv.List()
+	n := 0
+	for i, llen := 0, list.Len(); i < llen; i++ {
+		m := list.Get(i).Message().Interface()
+		n += protowire.SizeBytes(proto.Size(m)) + tagsize
+	}
+	return n
+}
+
+func appendMessageSliceValue(b []byte, listv pref.Value, wiretag uint64, opts marshalOptions) ([]byte, error) {
+	list := listv.List()
+	mopts := opts.Options()
+	for i, llen := 0, list.Len(); i < llen; i++ {
+		m := list.Get(i).Message().Interface()
+		b = protowire.AppendVarint(b, wiretag)
+		siz := proto.Size(m)
+		b = protowire.AppendVarint(b, uint64(siz))
+		var err error
+		b, err = mopts.MarshalAppend(b, m)
+		if err != nil {
+			return b, err
+		}
+	}
+	return b, nil
+}
+
+func consumeMessageSliceValue(b []byte, listv pref.Value, _ protowire.Number, wtyp protowire.Type, opts unmarshalOptions) (_ pref.Value, out unmarshalOutput, err error) {
+	list := listv.List()
+	if wtyp != protowire.BytesType {
+		return pref.Value{}, out, errUnknown
+	}
+	v, n := protowire.ConsumeBytes(b)
+	if n < 0 {
+		return pref.Value{}, out, protowire.ParseError(n)
+	}
+	m := list.NewElement()
+	o, err := opts.Options().UnmarshalState(piface.UnmarshalInput{
+		Buf:     v,
+		Message: m.Message(),
+	})
+	if err != nil {
+		return pref.Value{}, out, err
+	}
+	list.Append(m)
+	out.n = n
+	out.initialized = o.Flags&piface.UnmarshalInitialized != 0
+	return listv, out, nil
+}
+
+func isInitMessageSliceValue(listv pref.Value) error {
+	list := listv.List()
+	for i, llen := 0, list.Len(); i < llen; i++ {
+		m := list.Get(i).Message().Interface()
+		if err := proto.CheckInitialized(m); err != nil {
+			return err
+		}
+	}
+	return nil
+}
+
+var coderMessageSliceValue = valueCoderFuncs{
+	size:      sizeMessageSliceValue,
+	marshal:   appendMessageSliceValue,
+	unmarshal: consumeMessageSliceValue,
+	isInit:    isInitMessageSliceValue,
+	merge:     mergeMessageListValue,
+}
+
+func sizeGroupSliceValue(listv pref.Value, tagsize int, opts marshalOptions) int {
+	list := listv.List()
+	n := 0
+	for i, llen := 0, list.Len(); i < llen; i++ {
+		m := list.Get(i).Message().Interface()
+		n += 2*tagsize + proto.Size(m)
+	}
+	return n
+}
+
+func appendGroupSliceValue(b []byte, listv pref.Value, wiretag uint64, opts marshalOptions) ([]byte, error) {
+	list := listv.List()
+	mopts := opts.Options()
+	for i, llen := 0, list.Len(); i < llen; i++ {
+		m := list.Get(i).Message().Interface()
+		b = protowire.AppendVarint(b, wiretag) // start group
+		var err error
+		b, err = mopts.MarshalAppend(b, m)
+		if err != nil {
+			return b, err
+		}
+		b = protowire.AppendVarint(b, wiretag+1) // end group
+	}
+	return b, nil
+}
+
+func consumeGroupSliceValue(b []byte, listv pref.Value, num protowire.Number, wtyp protowire.Type, opts unmarshalOptions) (_ pref.Value, out unmarshalOutput, err error) {
+	list := listv.List()
+	if wtyp != protowire.StartGroupType {
+		return pref.Value{}, out, errUnknown
+	}
+	b, n := protowire.ConsumeGroup(num, b)
+	if n < 0 {
+		return pref.Value{}, out, protowire.ParseError(n)
+	}
+	m := list.NewElement()
+	o, err := opts.Options().UnmarshalState(piface.UnmarshalInput{
+		Buf:     b,
+		Message: m.Message(),
+	})
+	if err != nil {
+		return pref.Value{}, out, err
+	}
+	list.Append(m)
+	out.n = n
+	out.initialized = o.Flags&piface.UnmarshalInitialized != 0
+	return listv, out, nil
+}
+
+var coderGroupSliceValue = valueCoderFuncs{
+	size:      sizeGroupSliceValue,
+	marshal:   appendGroupSliceValue,
+	unmarshal: consumeGroupSliceValue,
+	isInit:    isInitMessageSliceValue,
+	merge:     mergeMessageListValue,
+}
+
+func makeGroupSliceFieldCoder(fd pref.FieldDescriptor, ft reflect.Type) pointerCoderFuncs {
+	num := fd.Number()
+	if mi := getMessageInfo(ft); mi != nil {
+		funcs := pointerCoderFuncs{
+			size:      sizeGroupSliceInfo,
+			marshal:   appendGroupSliceInfo,
+			unmarshal: consumeGroupSliceInfo,
+			merge:     mergeMessageSlice,
+		}
+		if needsInitCheck(mi.Desc) {
+			funcs.isInit = isInitMessageSliceInfo
+		}
+		return funcs
+	}
+	return pointerCoderFuncs{
+		size: func(p pointer, f *coderFieldInfo, opts marshalOptions) int {
+			return sizeGroupSlice(p, ft, f.tagsize, opts)
+		},
+		marshal: func(b []byte, p pointer, f *coderFieldInfo, opts marshalOptions) ([]byte, error) {
+			return appendGroupSlice(b, p, f.wiretag, ft, opts)
+		},
+		unmarshal: func(b []byte, p pointer, wtyp protowire.Type, f *coderFieldInfo, opts unmarshalOptions) (unmarshalOutput, error) {
+			return consumeGroupSlice(b, p, num, wtyp, ft, opts)
+		},
+		isInit: func(p pointer, f *coderFieldInfo) error {
+			return isInitMessageSlice(p, ft)
+		},
+		merge: mergeMessageSlice,
+	}
+}
+
+func sizeGroupSlice(p pointer, messageType reflect.Type, tagsize int, _ marshalOptions) int {
+	s := p.PointerSlice()
+	n := 0
+	for _, v := range s {
+		m := asMessage(v.AsValueOf(messageType.Elem()))
+		n += 2*tagsize + proto.Size(m)
+	}
+	return n
+}
+
+func appendGroupSlice(b []byte, p pointer, wiretag uint64, messageType reflect.Type, opts marshalOptions) ([]byte, error) {
+	s := p.PointerSlice()
+	var err error
+	for _, v := range s {
+		m := asMessage(v.AsValueOf(messageType.Elem()))
+		b = protowire.AppendVarint(b, wiretag) // start group
+		b, err = opts.Options().MarshalAppend(b, m)
+		if err != nil {
+			return b, err
+		}
+		b = protowire.AppendVarint(b, wiretag+1) // end group
+	}
+	return b, nil
+}
+
+func consumeGroupSlice(b []byte, p pointer, num protowire.Number, wtyp protowire.Type, goType reflect.Type, opts unmarshalOptions) (out unmarshalOutput, err error) {
+	if wtyp != protowire.StartGroupType {
+		return out, errUnknown
+	}
+	b, n := protowire.ConsumeGroup(num, b)
+	if n < 0 {
+		return out, protowire.ParseError(n)
+	}
+	mp := reflect.New(goType.Elem())
+	o, err := opts.Options().UnmarshalState(piface.UnmarshalInput{
+		Buf:     b,
+		Message: asMessage(mp).ProtoReflect(),
+	})
+	if err != nil {
+		return out, err
+	}
+	p.AppendPointerSlice(pointerOfValue(mp))
+	out.n = n
+	out.initialized = o.Flags&piface.UnmarshalInitialized != 0
+	return out, nil
+}
+
+func sizeGroupSliceInfo(p pointer, f *coderFieldInfo, opts marshalOptions) int {
+	s := p.PointerSlice()
+	n := 0
+	for _, v := range s {
+		n += 2*f.tagsize + f.mi.sizePointer(v, opts)
+	}
+	return n
+}
+
+func appendGroupSliceInfo(b []byte, p pointer, f *coderFieldInfo, opts marshalOptions) ([]byte, error) {
+	s := p.PointerSlice()
+	var err error
+	for _, v := range s {
+		b = protowire.AppendVarint(b, f.wiretag) // start group
+		b, err = f.mi.marshalAppendPointer(b, v, opts)
+		if err != nil {
+			return b, err
+		}
+		b = protowire.AppendVarint(b, f.wiretag+1) // end group
+	}
+	return b, nil
+}
+
+func consumeGroupSliceInfo(b []byte, p pointer, wtyp protowire.Type, f *coderFieldInfo, opts unmarshalOptions) (unmarshalOutput, error) {
+	if wtyp != protowire.StartGroupType {
+		return unmarshalOutput{}, errUnknown
+	}
+	m := reflect.New(f.mi.GoReflectType.Elem()).Interface()
+	mp := pointerOfIface(m)
+	out, err := f.mi.unmarshalPointer(b, mp, f.num, opts)
+	if err != nil {
+		return out, err
+	}
+	p.AppendPointerSlice(mp)
+	return out, nil
+}
+
+func asMessage(v reflect.Value) pref.ProtoMessage {
+	if m, ok := v.Interface().(pref.ProtoMessage); ok {
+		return m
+	}
+	return legacyWrapMessage(v).Interface()
+}

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

@@ -0,0 +1,389 @@
+// Copyright 2019 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package impl
+
+import (
+	"errors"
+	"reflect"
+	"sort"
+
+	"google.golang.org/protobuf/encoding/protowire"
+	"google.golang.org/protobuf/internal/genid"
+	pref "google.golang.org/protobuf/reflect/protoreflect"
+)
+
+type mapInfo struct {
+	goType     reflect.Type
+	keyWiretag uint64
+	valWiretag uint64
+	keyFuncs   valueCoderFuncs
+	valFuncs   valueCoderFuncs
+	keyZero    pref.Value
+	keyKind    pref.Kind
+	conv       *mapConverter
+}
+
+func encoderFuncsForMap(fd pref.FieldDescriptor, ft reflect.Type) (valueMessage *MessageInfo, funcs pointerCoderFuncs) {
+	// TODO: Consider generating specialized map coders.
+	keyField := fd.MapKey()
+	valField := fd.MapValue()
+	keyWiretag := protowire.EncodeTag(1, wireTypes[keyField.Kind()])
+	valWiretag := protowire.EncodeTag(2, wireTypes[valField.Kind()])
+	keyFuncs := encoderFuncsForValue(keyField)
+	valFuncs := encoderFuncsForValue(valField)
+	conv := newMapConverter(ft, fd)
+
+	mapi := &mapInfo{
+		goType:     ft,
+		keyWiretag: keyWiretag,
+		valWiretag: valWiretag,
+		keyFuncs:   keyFuncs,
+		valFuncs:   valFuncs,
+		keyZero:    keyField.Default(),
+		keyKind:    keyField.Kind(),
+		conv:       conv,
+	}
+	if valField.Kind() == pref.MessageKind {
+		valueMessage = getMessageInfo(ft.Elem())
+	}
+
+	funcs = pointerCoderFuncs{
+		size: func(p pointer, f *coderFieldInfo, opts marshalOptions) int {
+			return sizeMap(p.AsValueOf(ft).Elem(), mapi, f, opts)
+		},
+		marshal: func(b []byte, p pointer, f *coderFieldInfo, opts marshalOptions) ([]byte, error) {
+			return appendMap(b, p.AsValueOf(ft).Elem(), mapi, f, opts)
+		},
+		unmarshal: func(b []byte, p pointer, wtyp protowire.Type, f *coderFieldInfo, opts unmarshalOptions) (unmarshalOutput, error) {
+			mp := p.AsValueOf(ft)
+			if mp.Elem().IsNil() {
+				mp.Elem().Set(reflect.MakeMap(mapi.goType))
+			}
+			if f.mi == nil {
+				return consumeMap(b, mp.Elem(), wtyp, mapi, f, opts)
+			} else {
+				return consumeMapOfMessage(b, mp.Elem(), wtyp, mapi, f, opts)
+			}
+		},
+	}
+	switch valField.Kind() {
+	case pref.MessageKind:
+		funcs.merge = mergeMapOfMessage
+	case pref.BytesKind:
+		funcs.merge = mergeMapOfBytes
+	default:
+		funcs.merge = mergeMap
+	}
+	if valFuncs.isInit != nil {
+		funcs.isInit = func(p pointer, f *coderFieldInfo) error {
+			return isInitMap(p.AsValueOf(ft).Elem(), mapi, f)
+		}
+	}
+	return valueMessage, funcs
+}
+
+const (
+	mapKeyTagSize = 1 // field 1, tag size 1.
+	mapValTagSize = 1 // field 2, tag size 2.
+)
+
+func sizeMap(mapv reflect.Value, mapi *mapInfo, f *coderFieldInfo, opts marshalOptions) int {
+	if mapv.Len() == 0 {
+		return 0
+	}
+	n := 0
+	iter := mapRange(mapv)
+	for iter.Next() {
+		key := mapi.conv.keyConv.PBValueOf(iter.Key()).MapKey()
+		keySize := mapi.keyFuncs.size(key.Value(), mapKeyTagSize, opts)
+		var valSize int
+		value := mapi.conv.valConv.PBValueOf(iter.Value())
+		if f.mi == nil {
+			valSize = mapi.valFuncs.size(value, mapValTagSize, opts)
+		} else {
+			p := pointerOfValue(iter.Value())
+			valSize += mapValTagSize
+			valSize += protowire.SizeBytes(f.mi.sizePointer(p, opts))
+		}
+		n += f.tagsize + protowire.SizeBytes(keySize+valSize)
+	}
+	return n
+}
+
+func consumeMap(b []byte, mapv reflect.Value, wtyp protowire.Type, mapi *mapInfo, f *coderFieldInfo, opts unmarshalOptions) (out unmarshalOutput, err error) {
+	if wtyp != protowire.BytesType {
+		return out, errUnknown
+	}
+	b, n := protowire.ConsumeBytes(b)
+	if n < 0 {
+		return out, protowire.ParseError(n)
+	}
+	var (
+		key = mapi.keyZero
+		val = mapi.conv.valConv.New()
+	)
+	for len(b) > 0 {
+		num, wtyp, n := protowire.ConsumeTag(b)
+		if n < 0 {
+			return out, protowire.ParseError(n)
+		}
+		if num > protowire.MaxValidNumber {
+			return out, errors.New("invalid field number")
+		}
+		b = b[n:]
+		err := errUnknown
+		switch num {
+		case genid.MapEntry_Key_field_number:
+			var v pref.Value
+			var o unmarshalOutput
+			v, o, err = mapi.keyFuncs.unmarshal(b, key, num, wtyp, opts)
+			if err != nil {
+				break
+			}
+			key = v
+			n = o.n
+		case genid.MapEntry_Value_field_number:
+			var v pref.Value
+			var o unmarshalOutput
+			v, o, err = mapi.valFuncs.unmarshal(b, val, num, wtyp, opts)
+			if err != nil {
+				break
+			}
+			val = v
+			n = o.n
+		}
+		if err == errUnknown {
+			n = protowire.ConsumeFieldValue(num, wtyp, b)
+			if n < 0 {
+				return out, protowire.ParseError(n)
+			}
+		} else if err != nil {
+			return out, err
+		}
+		b = b[n:]
+	}
+	mapv.SetMapIndex(mapi.conv.keyConv.GoValueOf(key), mapi.conv.valConv.GoValueOf(val))
+	out.n = n
+	return out, nil
+}
+
+func consumeMapOfMessage(b []byte, mapv reflect.Value, wtyp protowire.Type, mapi *mapInfo, f *coderFieldInfo, opts unmarshalOptions) (out unmarshalOutput, err error) {
+	if wtyp != protowire.BytesType {
+		return out, errUnknown
+	}
+	b, n := protowire.ConsumeBytes(b)
+	if n < 0 {
+		return out, protowire.ParseError(n)
+	}
+	var (
+		key = mapi.keyZero
+		val = reflect.New(f.mi.GoReflectType.Elem())
+	)
+	for len(b) > 0 {
+		num, wtyp, n := protowire.ConsumeTag(b)
+		if n < 0 {
+			return out, protowire.ParseError(n)
+		}
+		if num > protowire.MaxValidNumber {
+			return out, errors.New("invalid field number")
+		}
+		b = b[n:]
+		err := errUnknown
+		switch num {
+		case 1:
+			var v pref.Value
+			var o unmarshalOutput
+			v, o, err = mapi.keyFuncs.unmarshal(b, key, num, wtyp, opts)
+			if err != nil {
+				break
+			}
+			key = v
+			n = o.n
+		case 2:
+			if wtyp != protowire.BytesType {
+				break
+			}
+			var v []byte
+			v, n = protowire.ConsumeBytes(b)
+			if n < 0 {
+				return out, protowire.ParseError(n)
+			}
+			var o unmarshalOutput
+			o, err = f.mi.unmarshalPointer(v, pointerOfValue(val), 0, opts)
+			if o.initialized {
+				// Consider this map item initialized so long as we see
+				// an initialized value.
+				out.initialized = true
+			}
+		}
+		if err == errUnknown {
+			n = protowire.ConsumeFieldValue(num, wtyp, b)
+			if n < 0 {
+				return out, protowire.ParseError(n)
+			}
+		} else if err != nil {
+			return out, err
+		}
+		b = b[n:]
+	}
+	mapv.SetMapIndex(mapi.conv.keyConv.GoValueOf(key), val)
+	out.n = n
+	return out, nil
+}
+
+func appendMapItem(b []byte, keyrv, valrv reflect.Value, mapi *mapInfo, f *coderFieldInfo, opts marshalOptions) ([]byte, error) {
+	if f.mi == nil {
+		key := mapi.conv.keyConv.PBValueOf(keyrv).MapKey()
+		val := mapi.conv.valConv.PBValueOf(valrv)
+		size := 0
+		size += mapi.keyFuncs.size(key.Value(), mapKeyTagSize, opts)
+		size += mapi.valFuncs.size(val, mapValTagSize, opts)
+		b = protowire.AppendVarint(b, uint64(size))
+		b, err := mapi.keyFuncs.marshal(b, key.Value(), mapi.keyWiretag, opts)
+		if err != nil {
+			return nil, err
+		}
+		return mapi.valFuncs.marshal(b, val, mapi.valWiretag, opts)
+	} else {
+		key := mapi.conv.keyConv.PBValueOf(keyrv).MapKey()
+		val := pointerOfValue(valrv)
+		valSize := f.mi.sizePointer(val, opts)
+		size := 0
+		size += mapi.keyFuncs.size(key.Value(), mapKeyTagSize, opts)
+		size += mapValTagSize + protowire.SizeBytes(valSize)
+		b = protowire.AppendVarint(b, uint64(size))
+		b, err := mapi.keyFuncs.marshal(b, key.Value(), mapi.keyWiretag, opts)
+		if err != nil {
+			return nil, err
+		}
+		b = protowire.AppendVarint(b, mapi.valWiretag)
+		b = protowire.AppendVarint(b, uint64(valSize))
+		return f.mi.marshalAppendPointer(b, val, opts)
+	}
+}
+
+func appendMap(b []byte, mapv reflect.Value, mapi *mapInfo, f *coderFieldInfo, opts marshalOptions) ([]byte, error) {
+	if mapv.Len() == 0 {
+		return b, nil
+	}
+	if opts.Deterministic() {
+		return appendMapDeterministic(b, mapv, mapi, f, opts)
+	}
+	iter := mapRange(mapv)
+	for iter.Next() {
+		var err error
+		b = protowire.AppendVarint(b, f.wiretag)
+		b, err = appendMapItem(b, iter.Key(), iter.Value(), mapi, f, opts)
+		if err != nil {
+			return b, err
+		}
+	}
+	return b, nil
+}
+
+func appendMapDeterministic(b []byte, mapv reflect.Value, mapi *mapInfo, f *coderFieldInfo, opts marshalOptions) ([]byte, error) {
+	keys := mapv.MapKeys()
+	sort.Slice(keys, func(i, j int) bool {
+		switch keys[i].Kind() {
+		case reflect.Bool:
+			return !keys[i].Bool() && keys[j].Bool()
+		case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64:
+			return keys[i].Int() < keys[j].Int()
+		case reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64, reflect.Uintptr:
+			return keys[i].Uint() < keys[j].Uint()
+		case reflect.Float32, reflect.Float64:
+			return keys[i].Float() < keys[j].Float()
+		case reflect.String:
+			return keys[i].String() < keys[j].String()
+		default:
+			panic("invalid kind: " + keys[i].Kind().String())
+		}
+	})
+	for _, key := range keys {
+		var err error
+		b = protowire.AppendVarint(b, f.wiretag)
+		b, err = appendMapItem(b, key, mapv.MapIndex(key), mapi, f, opts)
+		if err != nil {
+			return b, err
+		}
+	}
+	return b, nil
+}
+
+func isInitMap(mapv reflect.Value, mapi *mapInfo, f *coderFieldInfo) error {
+	if mi := f.mi; mi != nil {
+		mi.init()
+		if !mi.needsInitCheck {
+			return nil
+		}
+		iter := mapRange(mapv)
+		for iter.Next() {
+			val := pointerOfValue(iter.Value())
+			if err := mi.checkInitializedPointer(val); err != nil {
+				return err
+			}
+		}
+	} else {
+		iter := mapRange(mapv)
+		for iter.Next() {
+			val := mapi.conv.valConv.PBValueOf(iter.Value())
+			if err := mapi.valFuncs.isInit(val); err != nil {
+				return err
+			}
+		}
+	}
+	return nil
+}
+
+func mergeMap(dst, src pointer, f *coderFieldInfo, opts mergeOptions) {
+	dstm := dst.AsValueOf(f.ft).Elem()
+	srcm := src.AsValueOf(f.ft).Elem()
+	if srcm.Len() == 0 {
+		return
+	}
+	if dstm.IsNil() {
+		dstm.Set(reflect.MakeMap(f.ft))
+	}
+	iter := mapRange(srcm)
+	for iter.Next() {
+		dstm.SetMapIndex(iter.Key(), iter.Value())
+	}
+}
+
+func mergeMapOfBytes(dst, src pointer, f *coderFieldInfo, opts mergeOptions) {
+	dstm := dst.AsValueOf(f.ft).Elem()
+	srcm := src.AsValueOf(f.ft).Elem()
+	if srcm.Len() == 0 {
+		return
+	}
+	if dstm.IsNil() {
+		dstm.Set(reflect.MakeMap(f.ft))
+	}
+	iter := mapRange(srcm)
+	for iter.Next() {
+		dstm.SetMapIndex(iter.Key(), reflect.ValueOf(append(emptyBuf[:], iter.Value().Bytes()...)))
+	}
+}
+
+func mergeMapOfMessage(dst, src pointer, f *coderFieldInfo, opts mergeOptions) {
+	dstm := dst.AsValueOf(f.ft).Elem()
+	srcm := src.AsValueOf(f.ft).Elem()
+	if srcm.Len() == 0 {
+		return
+	}
+	if dstm.IsNil() {
+		dstm.Set(reflect.MakeMap(f.ft))
+	}
+	iter := mapRange(srcm)
+	for iter.Next() {
+		val := reflect.New(f.ft.Elem().Elem())
+		if f.mi != nil {
+			f.mi.mergePointer(pointerOfValue(val), pointerOfValue(iter.Value()), opts)
+		} else {
+			opts.Merge(asMessage(val), asMessage(iter.Value()))
+		}
+		dstm.SetMapIndex(iter.Key(), val)
+	}
+}

vendor/google.golang.org/protobuf/internal/impl/codec_map_go111.go

@@ -0,0 +1,37 @@
+// Copyright 2019 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build !go1.12
+
+package impl
+
+import "reflect"
+
+type mapIter struct {
+	v    reflect.Value
+	keys []reflect.Value
+}
+
+// mapRange provides a less-efficient equivalent to
+// the Go 1.12 reflect.Value.MapRange method.
+func mapRange(v reflect.Value) *mapIter {
+	return &mapIter{v: v}
+}
+
+func (i *mapIter) Next() bool {
+	if i.keys == nil {
+		i.keys = i.v.MapKeys()
+	} else {
+		i.keys = i.keys[1:]
+	}
+	return len(i.keys) > 0
+}
+
+func (i *mapIter) Key() reflect.Value {
+	return i.keys[0]
+}
+
+func (i *mapIter) Value() reflect.Value {
+	return i.v.MapIndex(i.keys[0])
+}

vendor/google.golang.org/protobuf/internal/impl/codec_map_go112.go

@@ -0,0 +1,11 @@
+// Copyright 2019 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build go1.12
+
+package impl
+
+import "reflect"
+
+func mapRange(v reflect.Value) *reflect.MapIter { return v.MapRange() }

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

@@ -0,0 +1,159 @@
+// Copyright 2019 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package impl
+
+import (
+	"fmt"
+	"reflect"
+	"sort"
+
+	"google.golang.org/protobuf/encoding/protowire"
+	"google.golang.org/protobuf/internal/encoding/messageset"
+	"google.golang.org/protobuf/internal/fieldsort"
+	pref "google.golang.org/protobuf/reflect/protoreflect"
+	piface "google.golang.org/protobuf/runtime/protoiface"
+)
+
+// coderMessageInfo contains per-message information used by the fast-path functions.
+// This is a different type from MessageInfo to keep MessageInfo as general-purpose as
+// possible.
+type coderMessageInfo struct {
+	methods piface.Methods
+
+	orderedCoderFields []*coderFieldInfo
+	denseCoderFields   []*coderFieldInfo
+	coderFields        map[protowire.Number]*coderFieldInfo
+	sizecacheOffset    offset
+	unknownOffset      offset
+	extensionOffset    offset
+	needsInitCheck     bool
+	isMessageSet       bool
+	numRequiredFields  uint8
+}
+
+type coderFieldInfo struct {
+	funcs      pointerCoderFuncs // fast-path per-field functions
+	mi         *MessageInfo      // field's message
+	ft         reflect.Type
+	validation validationInfo   // information used by message validation
+	num        pref.FieldNumber // field number
+	offset     offset           // struct field offset
+	wiretag    uint64           // field tag (number + wire type)
+	tagsize    int              // size of the varint-encoded tag
+	isPointer  bool             // true if IsNil may be called on the struct field
+	isRequired bool             // true if field is required
+}
+
+func (mi *MessageInfo) makeCoderMethods(t reflect.Type, si structInfo) {
+	mi.sizecacheOffset = si.sizecacheOffset
+	mi.unknownOffset = si.unknownOffset
+	mi.extensionOffset = si.extensionOffset
+
+	mi.coderFields = make(map[protowire.Number]*coderFieldInfo)
+	fields := mi.Desc.Fields()
+	preallocFields := make([]coderFieldInfo, fields.Len())
+	for i := 0; i < fields.Len(); i++ {
+		fd := fields.Get(i)
+
+		fs := si.fieldsByNumber[fd.Number()]
+		isOneof := fd.ContainingOneof() != nil && !fd.ContainingOneof().IsSynthetic()
+		if isOneof {
+			fs = si.oneofsByName[fd.ContainingOneof().Name()]
+		}
+		ft := fs.Type
+		var wiretag uint64
+		if !fd.IsPacked() {
+			wiretag = protowire.EncodeTag(fd.Number(), wireTypes[fd.Kind()])
+		} else {
+			wiretag = protowire.EncodeTag(fd.Number(), protowire.BytesType)
+		}
+		var fieldOffset offset
+		var funcs pointerCoderFuncs
+		var childMessage *MessageInfo
+		switch {
+		case isOneof:
+			fieldOffset = offsetOf(fs, mi.Exporter)
+		case fd.IsWeak():
+			fieldOffset = si.weakOffset
+			funcs = makeWeakMessageFieldCoder(fd)
+		default:
+			fieldOffset = offsetOf(fs, mi.Exporter)
+			childMessage, funcs = fieldCoder(fd, ft)
+		}
+		cf := &preallocFields[i]
+		*cf = coderFieldInfo{
+			num:        fd.Number(),
+			offset:     fieldOffset,
+			wiretag:    wiretag,
+			ft:         ft,
+			tagsize:    protowire.SizeVarint(wiretag),
+			funcs:      funcs,
+			mi:         childMessage,
+			validation: newFieldValidationInfo(mi, si, fd, ft),
+			isPointer:  fd.Cardinality() == pref.Repeated || fd.HasPresence(),
+			isRequired: fd.Cardinality() == pref.Required,
+		}
+		mi.orderedCoderFields = append(mi.orderedCoderFields, cf)
+		mi.coderFields[cf.num] = cf
+	}
+	for i, oneofs := 0, mi.Desc.Oneofs(); i < oneofs.Len(); i++ {
+		if od := oneofs.Get(i); !od.IsSynthetic() {
+			mi.initOneofFieldCoders(od, si)
+		}
+	}
+	if messageset.IsMessageSet(mi.Desc) {
+		if !mi.extensionOffset.IsValid() {
+			panic(fmt.Sprintf("%v: MessageSet with no extensions field", mi.Desc.FullName()))
+		}
+		if !mi.unknownOffset.IsValid() {
+			panic(fmt.Sprintf("%v: MessageSet with no unknown field", mi.Desc.FullName()))
+		}
+		mi.isMessageSet = true
+	}
+	sort.Slice(mi.orderedCoderFields, func(i, j int) bool {
+		return mi.orderedCoderFields[i].num < mi.orderedCoderFields[j].num
+	})
+
+	var maxDense pref.FieldNumber
+	for _, cf := range mi.orderedCoderFields {
+		if cf.num >= 16 && cf.num >= 2*maxDense {
+			break
+		}
+		maxDense = cf.num
+	}
+	mi.denseCoderFields = make([]*coderFieldInfo, maxDense+1)
+	for _, cf := range mi.orderedCoderFields {
+		if int(cf.num) >= len(mi.denseCoderFields) {
+			break
+		}
+		mi.denseCoderFields[cf.num] = cf
+	}
+
+	// To preserve compatibility with historic wire output, marshal oneofs last.
+	if mi.Desc.Oneofs().Len() > 0 {
+		sort.Slice(mi.orderedCoderFields, func(i, j int) bool {
+			fi := fields.ByNumber(mi.orderedCoderFields[i].num)
+			fj := fields.ByNumber(mi.orderedCoderFields[j].num)
+			return fieldsort.Less(fi, fj)
+		})
+	}
+
+	mi.needsInitCheck = needsInitCheck(mi.Desc)
+	if mi.methods.Marshal == nil && mi.methods.Size == nil {
+		mi.methods.Flags |= piface.SupportMarshalDeterministic
+		mi.methods.Marshal = mi.marshal
+		mi.methods.Size = mi.size
+	}
+	if mi.methods.Unmarshal == nil {
+		mi.methods.Flags |= piface.SupportUnmarshalDiscardUnknown
+		mi.methods.Unmarshal = mi.unmarshal
+	}
+	if mi.methods.CheckInitialized == nil {
+		mi.methods.CheckInitialized = mi.checkInitialized
+	}
+	if mi.methods.Merge == nil {
+		mi.methods.Merge = mi.merge
+	}
+}

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

@@ -0,0 +1,120 @@
+// Copyright 2019 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package impl
+
+import (
+	"sort"
+
+	"google.golang.org/protobuf/encoding/protowire"
+	"google.golang.org/protobuf/internal/encoding/messageset"
+	"google.golang.org/protobuf/internal/errors"
+	"google.golang.org/protobuf/internal/flags"
+)
+
+func sizeMessageSet(mi *MessageInfo, p pointer, opts marshalOptions) (size int) {
+	if !flags.ProtoLegacy {
+		return 0
+	}
+
+	ext := *p.Apply(mi.extensionOffset).Extensions()
+	for _, x := range ext {
+		xi := getExtensionFieldInfo(x.Type())
+		if xi.funcs.size == nil {
+			continue
+		}
+		num, _ := protowire.DecodeTag(xi.wiretag)
+		size += messageset.SizeField(num)
+		size += xi.funcs.size(x.Value(), protowire.SizeTag(messageset.FieldMessage), opts)
+	}
+
+	unknown := *p.Apply(mi.unknownOffset).Bytes()
+	size += messageset.SizeUnknown(unknown)
+
+	return size
+}
+
+func marshalMessageSet(mi *MessageInfo, b []byte, p pointer, opts marshalOptions) ([]byte, error) {
+	if !flags.ProtoLegacy {
+		return b, errors.New("no support for message_set_wire_format")
+	}
+
+	ext := *p.Apply(mi.extensionOffset).Extensions()
+	switch len(ext) {
+	case 0:
+	case 1:
+		// Fast-path for one extension: Don't bother sorting the keys.
+		for _, x := range ext {
+			var err error
+			b, err = marshalMessageSetField(mi, b, x, opts)
+			if err != nil {
+				return b, err
+			}
+		}
+	default:
+		// Sort the keys to provide a deterministic encoding.
+		// Not sure this is required, but the old code does it.
+		keys := make([]int, 0, len(ext))
+		for k := range ext {
+			keys = append(keys, int(k))
+		}
+		sort.Ints(keys)
+		for _, k := range keys {
+			var err error
+			b, err = marshalMessageSetField(mi, b, ext[int32(k)], opts)
+			if err != nil {
+				return b, err
+			}
+		}
+	}
+
+	unknown := *p.Apply(mi.unknownOffset).Bytes()
+	b, err := messageset.AppendUnknown(b, unknown)
+	if err != nil {
+		return b, err
+	}
+
+	return b, nil
+}
+
+func marshalMessageSetField(mi *MessageInfo, b []byte, x ExtensionField, opts marshalOptions) ([]byte, error) {
+	xi := getExtensionFieldInfo(x.Type())
+	num, _ := protowire.DecodeTag(xi.wiretag)
+	b = messageset.AppendFieldStart(b, num)
+	b, err := xi.funcs.marshal(b, x.Value(), protowire.EncodeTag(messageset.FieldMessage, protowire.BytesType), opts)
+	if err != nil {
+		return b, err
+	}
+	b = messageset.AppendFieldEnd(b)
+	return b, nil
+}
+
+func unmarshalMessageSet(mi *MessageInfo, b []byte, p pointer, opts unmarshalOptions) (out unmarshalOutput, err error) {
+	if !flags.ProtoLegacy {
+		return out, errors.New("no support for message_set_wire_format")
+	}
+
+	ep := p.Apply(mi.extensionOffset).Extensions()
+	if *ep == nil {
+		*ep = make(map[int32]ExtensionField)
+	}
+	ext := *ep
+	unknown := p.Apply(mi.unknownOffset).Bytes()
+	initialized := true
+	err = messageset.Unmarshal(b, true, func(num protowire.Number, v []byte) error {
+		o, err := mi.unmarshalExtension(v, num, protowire.BytesType, ext, opts)
+		if err == errUnknown {
+			*unknown = protowire.AppendTag(*unknown, num, protowire.BytesType)
+			*unknown = append(*unknown, v...)
+			return nil
+		}
+		if !o.initialized {
+			initialized = false
+		}
+		return err
+	})
+	out.n = len(b)
+	out.initialized = initialized
+	return out, err
+}

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

@@ -0,0 +1,209 @@
+// Copyright 2019 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build purego appengine
+
+package impl
+
+import (
+	"reflect"
+
+	"google.golang.org/protobuf/encoding/protowire"
+)
+
+func sizeEnum(p pointer, f *coderFieldInfo, _ marshalOptions) (size int) {
+	v := p.v.Elem().Int()
+	return f.tagsize + protowire.SizeVarint(uint64(v))
+}
+
+func appendEnum(b []byte, p pointer, f *coderFieldInfo, opts marshalOptions) ([]byte, error) {
+	v := p.v.Elem().Int()
+	b = protowire.AppendVarint(b, f.wiretag)
+	b = protowire.AppendVarint(b, uint64(v))
+	return b, nil
+}
+
+func consumeEnum(b []byte, p pointer, wtyp protowire.Type, f *coderFieldInfo, _ unmarshalOptions) (out unmarshalOutput, err error) {
+	if wtyp != protowire.VarintType {
+		return out, errUnknown
+	}
+	v, n := protowire.ConsumeVarint(b)
+	if n < 0 {
+		return out, protowire.ParseError(n)
+	}
+	p.v.Elem().SetInt(int64(v))
+	out.n = n
+	return out, nil
+}
+
+func mergeEnum(dst, src pointer, _ *coderFieldInfo, _ mergeOptions) {
+	dst.v.Elem().Set(src.v.Elem())
+}
+
+var coderEnum = pointerCoderFuncs{
+	size:      sizeEnum,
+	marshal:   appendEnum,
+	unmarshal: consumeEnum,
+	merge:     mergeEnum,
+}
+
+func sizeEnumNoZero(p pointer, f *coderFieldInfo, opts marshalOptions) (size int) {
+	if p.v.Elem().Int() == 0 {
+		return 0
+	}
+	return sizeEnum(p, f, opts)
+}
+
+func appendEnumNoZero(b []byte, p pointer, f *coderFieldInfo, opts marshalOptions) ([]byte, error) {
+	if p.v.Elem().Int() == 0 {
+		return b, nil
+	}
+	return appendEnum(b, p, f, opts)
+}
+
+func mergeEnumNoZero(dst, src pointer, _ *coderFieldInfo, _ mergeOptions) {
+	if src.v.Elem().Int() != 0 {
+		dst.v.Elem().Set(src.v.Elem())
+	}
+}
+
+var coderEnumNoZero = pointerCoderFuncs{
+	size:      sizeEnumNoZero,
+	marshal:   appendEnumNoZero,
+	unmarshal: consumeEnum,
+	merge:     mergeEnumNoZero,
+}
+
+func sizeEnumPtr(p pointer, f *coderFieldInfo, opts marshalOptions) (size int) {
+	return sizeEnum(pointer{p.v.Elem()}, f, opts)
+}
+
+func appendEnumPtr(b []byte, p pointer, f *coderFieldInfo, opts marshalOptions) ([]byte, error) {
+	return appendEnum(b, pointer{p.v.Elem()}, f, opts)
+}
+
+func consumeEnumPtr(b []byte, p pointer, wtyp protowire.Type, f *coderFieldInfo, opts unmarshalOptions) (out unmarshalOutput, err error) {
+	if wtyp != protowire.VarintType {
+		return out, errUnknown
+	}
+	if p.v.Elem().IsNil() {
+		p.v.Elem().Set(reflect.New(p.v.Elem().Type().Elem()))
+	}
+	return consumeEnum(b, pointer{p.v.Elem()}, wtyp, f, opts)
+}
+
+func mergeEnumPtr(dst, src pointer, _ *coderFieldInfo, _ mergeOptions) {
+	if !src.v.Elem().IsNil() {
+		v := reflect.New(dst.v.Type().Elem().Elem())
+		v.Elem().Set(src.v.Elem().Elem())
+		dst.v.Elem().Set(v)
+	}
+}
+
+var coderEnumPtr = pointerCoderFuncs{
+	size:      sizeEnumPtr,
+	marshal:   appendEnumPtr,
+	unmarshal: consumeEnumPtr,
+	merge:     mergeEnumPtr,
+}
+
+func sizeEnumSlice(p pointer, f *coderFieldInfo, opts marshalOptions) (size int) {
+	s := p.v.Elem()
+	for i, llen := 0, s.Len(); i < llen; i++ {
+		size += protowire.SizeVarint(uint64(s.Index(i).Int())) + f.tagsize
+	}
+	return size
+}
+
+func appendEnumSlice(b []byte, p pointer, f *coderFieldInfo, opts marshalOptions) ([]byte, error) {
+	s := p.v.Elem()
+	for i, llen := 0, s.Len(); i < llen; i++ {
+		b = protowire.AppendVarint(b, f.wiretag)
+		b = protowire.AppendVarint(b, uint64(s.Index(i).Int()))
+	}
+	return b, nil
+}
+
+func consumeEnumSlice(b []byte, p pointer, wtyp protowire.Type, f *coderFieldInfo, opts unmarshalOptions) (out unmarshalOutput, err error) {
+	s := p.v.Elem()
+	if wtyp == protowire.BytesType {
+		b, n := protowire.ConsumeBytes(b)
+		if n < 0 {
+			return out, protowire.ParseError(n)
+		}
+		for len(b) > 0 {
+			v, n := protowire.ConsumeVarint(b)
+			if n < 0 {
+				return out, protowire.ParseError(n)
+			}
+			rv := reflect.New(s.Type().Elem()).Elem()
+			rv.SetInt(int64(v))
+			s.Set(reflect.Append(s, rv))
+			b = b[n:]
+		}
+		out.n = n
+		return out, nil
+	}
+	if wtyp != protowire.VarintType {
+		return out, errUnknown
+	}
+	v, n := protowire.ConsumeVarint(b)
+	if n < 0 {
+		return out, protowire.ParseError(n)
+	}
+	rv := reflect.New(s.Type().Elem()).Elem()
+	rv.SetInt(int64(v))
+	s.Set(reflect.Append(s, rv))
+	out.n = n
+	return out, nil
+}
+
+func mergeEnumSlice(dst, src pointer, _ *coderFieldInfo, _ mergeOptions) {
+	dst.v.Elem().Set(reflect.AppendSlice(dst.v.Elem(), src.v.Elem()))
+}
+
+var coderEnumSlice = pointerCoderFuncs{
+	size:      sizeEnumSlice,
+	marshal:   appendEnumSlice,
+	unmarshal: consumeEnumSlice,
+	merge:     mergeEnumSlice,
+}
+
+func sizeEnumPackedSlice(p pointer, f *coderFieldInfo, opts marshalOptions) (size int) {
+	s := p.v.Elem()
+	llen := s.Len()
+	if llen == 0 {
+		return 0
+	}
+	n := 0
+	for i := 0; i < llen; i++ {
+		n += protowire.SizeVarint(uint64(s.Index(i).Int()))
+	}
+	return f.tagsize + protowire.SizeBytes(n)
+}
+
+func appendEnumPackedSlice(b []byte, p pointer, f *coderFieldInfo, opts marshalOptions) ([]byte, error) {
+	s := p.v.Elem()
+	llen := s.Len()
+	if llen == 0 {
+		return b, nil
+	}
+	b = protowire.AppendVarint(b, f.wiretag)
+	n := 0
+	for i := 0; i < llen; i++ {
+		n += protowire.SizeVarint(uint64(s.Index(i).Int()))
+	}
+	b = protowire.AppendVarint(b, uint64(n))
+	for i := 0; i < llen; i++ {
+		b = protowire.AppendVarint(b, uint64(s.Index(i).Int()))
+	}
+	return b, nil
+}
+
+var coderEnumPackedSlice = pointerCoderFuncs{
+	size:      sizeEnumPackedSlice,
+	marshal:   appendEnumPackedSlice,
+	unmarshal: consumeEnumSlice,
+	merge:     mergeEnumSlice,
+}

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

@@ -0,0 +1,557 @@
+// Copyright 2019 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package impl
+
+import (
+	"fmt"
+	"reflect"
+
+	"google.golang.org/protobuf/encoding/protowire"
+	"google.golang.org/protobuf/internal/strs"
+	pref "google.golang.org/protobuf/reflect/protoreflect"
+)
+
+// pointerCoderFuncs is a set of pointer encoding functions.
+type pointerCoderFuncs struct {
+	mi        *MessageInfo
+	size      func(p pointer, f *coderFieldInfo, opts marshalOptions) int
+	marshal   func(b []byte, p pointer, f *coderFieldInfo, opts marshalOptions) ([]byte, error)
+	unmarshal func(b []byte, p pointer, wtyp protowire.Type, f *coderFieldInfo, opts unmarshalOptions) (unmarshalOutput, error)
+	isInit    func(p pointer, f *coderFieldInfo) error
+	merge     func(dst, src pointer, f *coderFieldInfo, opts mergeOptions)
+}
+
+// valueCoderFuncs is a set of protoreflect.Value encoding functions.
+type valueCoderFuncs struct {
+	size      func(v pref.Value, tagsize int, opts marshalOptions) int
+	marshal   func(b []byte, v pref.Value, wiretag uint64, opts marshalOptions) ([]byte, error)
+	unmarshal func(b []byte, v pref.Value, num protowire.Number, wtyp protowire.Type, opts unmarshalOptions) (pref.Value, unmarshalOutput, error)
+	isInit    func(v pref.Value) error
+	merge     func(dst, src pref.Value, opts mergeOptions) pref.Value
+}
+
+// fieldCoder returns pointer functions for a field, used for operating on
+// struct fields.
+func fieldCoder(fd pref.FieldDescriptor, ft reflect.Type) (*MessageInfo, pointerCoderFuncs) {
+	switch {
+	case fd.IsMap():
+		return encoderFuncsForMap(fd, ft)
+	case fd.Cardinality() == pref.Repeated && !fd.IsPacked():
+		// Repeated fields (not packed).
+		if ft.Kind() != reflect.Slice {
+			break
+		}
+		ft := ft.Elem()
+		switch fd.Kind() {
+		case pref.BoolKind:
+			if ft.Kind() == reflect.Bool {
+				return nil, coderBoolSlice
+			}
+		case pref.EnumKind:
+			if ft.Kind() == reflect.Int32 {
+				return nil, coderEnumSlice
+			}
+		case pref.Int32Kind:
+			if ft.Kind() == reflect.Int32 {
+				return nil, coderInt32Slice
+			}
+		case pref.Sint32Kind:
+			if ft.Kind() == reflect.Int32 {
+				return nil, coderSint32Slice
+			}
+		case pref.Uint32Kind:
+			if ft.Kind() == reflect.Uint32 {
+				return nil, coderUint32Slice
+			}
+		case pref.Int64Kind:
+			if ft.Kind() == reflect.Int64 {
+				return nil, coderInt64Slice
+			}
+		case pref.Sint64Kind:
+			if ft.Kind() == reflect.Int64 {
+				return nil, coderSint64Slice
+			}
+		case pref.Uint64Kind:
+			if ft.Kind() == reflect.Uint64 {
+				return nil, coderUint64Slice
+			}
+		case pref.Sfixed32Kind:
+			if ft.Kind() == reflect.Int32 {
+				return nil, coderSfixed32Slice
+			}
+		case pref.Fixed32Kind:
+			if ft.Kind() == reflect.Uint32 {
+				return nil, coderFixed32Slice
+			}
+		case pref.FloatKind:
+			if ft.Kind() == reflect.Float32 {
+				return nil, coderFloatSlice
+			}
+		case pref.Sfixed64Kind:
+			if ft.Kind() == reflect.Int64 {
+				return nil, coderSfixed64Slice
+			}
+		case pref.Fixed64Kind:
+			if ft.Kind() == reflect.Uint64 {
+				return nil, coderFixed64Slice
+			}
+		case pref.DoubleKind:
+			if ft.Kind() == reflect.Float64 {
+				return nil, coderDoubleSlice
+			}
+		case pref.StringKind:
+			if ft.Kind() == reflect.String && strs.EnforceUTF8(fd) {
+				return nil, coderStringSliceValidateUTF8
+			}
+			if ft.Kind() == reflect.String {
+				return nil, coderStringSlice
+			}
+			if ft.Kind() == reflect.Slice && ft.Elem().Kind() == reflect.Uint8 && strs.EnforceUTF8(fd) {
+				return nil, coderBytesSliceValidateUTF8
+			}
+			if ft.Kind() == reflect.Slice && ft.Elem().Kind() == reflect.Uint8 {
+				return nil, coderBytesSlice
+			}
+		case pref.BytesKind:
+			if ft.Kind() == reflect.String {
+				return nil, coderStringSlice
+			}
+			if ft.Kind() == reflect.Slice && ft.Elem().Kind() == reflect.Uint8 {
+				return nil, coderBytesSlice
+			}
+		case pref.MessageKind:
+			return getMessageInfo(ft), makeMessageSliceFieldCoder(fd, ft)
+		case pref.GroupKind:
+			return getMessageInfo(ft), makeGroupSliceFieldCoder(fd, ft)
+		}
+	case fd.Cardinality() == pref.Repeated && fd.IsPacked():
+		// Packed repeated fields.
+		//
+		// Only repeated fields of primitive numeric types
+		// (Varint, Fixed32, or Fixed64 wire type) can be packed.
+		if ft.Kind() != reflect.Slice {
+			break
+		}
+		ft := ft.Elem()
+		switch fd.Kind() {
+		case pref.BoolKind:
+			if ft.Kind() == reflect.Bool {
+				return nil, coderBoolPackedSlice
+			}
+		case pref.EnumKind:
+			if ft.Kind() == reflect.Int32 {
+				return nil, coderEnumPackedSlice
+			}
+		case pref.Int32Kind:
+			if ft.Kind() == reflect.Int32 {
+				return nil, coderInt32PackedSlice
+			}
+		case pref.Sint32Kind:
+			if ft.Kind() == reflect.Int32 {
+				return nil, coderSint32PackedSlice
+			}
+		case pref.Uint32Kind:
+			if ft.Kind() == reflect.Uint32 {
+				return nil, coderUint32PackedSlice
+			}
+		case pref.Int64Kind:
+			if ft.Kind() == reflect.Int64 {
+				return nil, coderInt64PackedSlice
+			}
+		case pref.Sint64Kind:
+			if ft.Kind() == reflect.Int64 {
+				return nil, coderSint64PackedSlice
+			}
+		case pref.Uint64Kind:
+			if ft.Kind() == reflect.Uint64 {
+				return nil, coderUint64PackedSlice
+			}
+		case pref.Sfixed32Kind:
+			if ft.Kind() == reflect.Int32 {
+				return nil, coderSfixed32PackedSlice
+			}
+		case pref.Fixed32Kind:
+			if ft.Kind() == reflect.Uint32 {
+				return nil, coderFixed32PackedSlice
+			}
+		case pref.FloatKind:
+			if ft.Kind() == reflect.Float32 {
+				return nil, coderFloatPackedSlice
+			}
+		case pref.Sfixed64Kind:
+			if ft.Kind() == reflect.Int64 {
+				return nil, coderSfixed64PackedSlice
+			}
+		case pref.Fixed64Kind:
+			if ft.Kind() == reflect.Uint64 {
+				return nil, coderFixed64PackedSlice
+			}
+		case pref.DoubleKind:
+			if ft.Kind() == reflect.Float64 {
+				return nil, coderDoublePackedSlice
+			}
+		}
+	case fd.Kind() == pref.MessageKind:
+		return getMessageInfo(ft), makeMessageFieldCoder(fd, ft)
+	case fd.Kind() == pref.GroupKind:
+		return getMessageInfo(ft), makeGroupFieldCoder(fd, ft)
+	case fd.Syntax() == pref.Proto3 && fd.ContainingOneof() == nil:
+		// Populated oneof fields always encode even if set to the zero value,
+		// which normally are not encoded in proto3.
+		switch fd.Kind() {
+		case pref.BoolKind:
+			if ft.Kind() == reflect.Bool {
+				return nil, coderBoolNoZero
+			}
+		case pref.EnumKind:
+			if ft.Kind() == reflect.Int32 {
+				return nil, coderEnumNoZero
+			}
+		case pref.Int32Kind:
+			if ft.Kind() == reflect.Int32 {
+				return nil, coderInt32NoZero
+			}
+		case pref.Sint32Kind:
+			if ft.Kind() == reflect.Int32 {
+				return nil, coderSint32NoZero
+			}
+		case pref.Uint32Kind:
+			if ft.Kind() == reflect.Uint32 {
+				return nil, coderUint32NoZero
+			}
+		case pref.Int64Kind:
+			if ft.Kind() == reflect.Int64 {
+				return nil, coderInt64NoZero
+			}
+		case pref.Sint64Kind:
+			if ft.Kind() == reflect.Int64 {
+				return nil, coderSint64NoZero
+			}
+		case pref.Uint64Kind:
+			if ft.Kind() == reflect.Uint64 {
+				return nil, coderUint64NoZero
+			}
+		case pref.Sfixed32Kind:
+			if ft.Kind() == reflect.Int32 {
+				return nil, coderSfixed32NoZero
+			}
+		case pref.Fixed32Kind:
+			if ft.Kind() == reflect.Uint32 {
+				return nil, coderFixed32NoZero
+			}
+		case pref.FloatKind:
+			if ft.Kind() == reflect.Float32 {
+				return nil, coderFloatNoZero
+			}
+		case pref.Sfixed64Kind:
+			if ft.Kind() == reflect.Int64 {
+				return nil, coderSfixed64NoZero
+			}
+		case pref.Fixed64Kind:
+			if ft.Kind() == reflect.Uint64 {
+				return nil, coderFixed64NoZero
+			}
+		case pref.DoubleKind:
+			if ft.Kind() == reflect.Float64 {
+				return nil, coderDoubleNoZero
+			}
+		case pref.StringKind:
+			if ft.Kind() == reflect.String && strs.EnforceUTF8(fd) {
+				return nil, coderStringNoZeroValidateUTF8
+			}
+			if ft.Kind() == reflect.String {
+				return nil, coderStringNoZero
+			}
+			if ft.Kind() == reflect.Slice && ft.Elem().Kind() == reflect.Uint8 && strs.EnforceUTF8(fd) {
+				return nil, coderBytesNoZeroValidateUTF8
+			}
+			if ft.Kind() == reflect.Slice && ft.Elem().Kind() == reflect.Uint8 {
+				return nil, coderBytesNoZero
+			}
+		case pref.BytesKind:
+			if ft.Kind() == reflect.String {
+				return nil, coderStringNoZero
+			}
+			if ft.Kind() == reflect.Slice && ft.Elem().Kind() == reflect.Uint8 {
+				return nil, coderBytesNoZero
+			}
+		}
+	case ft.Kind() == reflect.Ptr:
+		ft := ft.Elem()
+		switch fd.Kind() {
+		case pref.BoolKind:
+			if ft.Kind() == reflect.Bool {
+				return nil, coderBoolPtr
+			}
+		case pref.EnumKind:
+			if ft.Kind() == reflect.Int32 {
+				return nil, coderEnumPtr
+			}
+		case pref.Int32Kind:
+			if ft.Kind() == reflect.Int32 {
+				return nil, coderInt32Ptr
+			}
+		case pref.Sint32Kind:
+			if ft.Kind() == reflect.Int32 {
+				return nil, coderSint32Ptr
+			}
+		case pref.Uint32Kind:
+			if ft.Kind() == reflect.Uint32 {
+				return nil, coderUint32Ptr
+			}
+		case pref.Int64Kind:
+			if ft.Kind() == reflect.Int64 {
+				return nil, coderInt64Ptr
+			}
+		case pref.Sint64Kind:
+			if ft.Kind() == reflect.Int64 {
+				return nil, coderSint64Ptr
+			}
+		case pref.Uint64Kind:
+			if ft.Kind() == reflect.Uint64 {
+				return nil, coderUint64Ptr
+			}
+		case pref.Sfixed32Kind:
+			if ft.Kind() == reflect.Int32 {
+				return nil, coderSfixed32Ptr
+			}
+		case pref.Fixed32Kind:
+			if ft.Kind() == reflect.Uint32 {
+				return nil, coderFixed32Ptr
+			}
+		case pref.FloatKind:
+			if ft.Kind() == reflect.Float32 {
+				return nil, coderFloatPtr
+			}
+		case pref.Sfixed64Kind:
+			if ft.Kind() == reflect.Int64 {
+				return nil, coderSfixed64Ptr
+			}
+		case pref.Fixed64Kind:
+			if ft.Kind() == reflect.Uint64 {
+				return nil, coderFixed64Ptr
+			}
+		case pref.DoubleKind:
+			if ft.Kind() == reflect.Float64 {
+				return nil, coderDoublePtr
+			}
+		case pref.StringKind:
+			if ft.Kind() == reflect.String && strs.EnforceUTF8(fd) {
+				return nil, coderStringPtrValidateUTF8
+			}
+			if ft.Kind() == reflect.String {
+				return nil, coderStringPtr
+			}
+		case pref.BytesKind:
+			if ft.Kind() == reflect.String {
+				return nil, coderStringPtr
+			}
+		}
+	default:
+		switch fd.Kind() {
+		case pref.BoolKind:
+			if ft.Kind() == reflect.Bool {
+				return nil, coderBool
+			}
+		case pref.EnumKind:
+			if ft.Kind() == reflect.Int32 {
+				return nil, coderEnum
+			}
+		case pref.Int32Kind:
+			if ft.Kind() == reflect.Int32 {
+				return nil, coderInt32
+			}
+		case pref.Sint32Kind:
+			if ft.Kind() == reflect.Int32 {
+				return nil, coderSint32
+			}
+		case pref.Uint32Kind:
+			if ft.Kind() == reflect.Uint32 {
+				return nil, coderUint32
+			}
+		case pref.Int64Kind:
+			if ft.Kind() == reflect.Int64 {
+				return nil, coderInt64
+			}
+		case pref.Sint64Kind:
+			if ft.Kind() == reflect.Int64 {
+				return nil, coderSint64
+			}
+		case pref.Uint64Kind:
+			if ft.Kind() == reflect.Uint64 {
+				return nil, coderUint64
+			}
+		case pref.Sfixed32Kind:
+			if ft.Kind() == reflect.Int32 {
+				return nil, coderSfixed32
+			}
+		case pref.Fixed32Kind:
+			if ft.Kind() == reflect.Uint32 {
+				return nil, coderFixed32
+			}
+		case pref.FloatKind:
+			if ft.Kind() == reflect.Float32 {
+				return nil, coderFloat
+			}
+		case pref.Sfixed64Kind:
+			if ft.Kind() == reflect.Int64 {
+				return nil, coderSfixed64
+			}
+		case pref.Fixed64Kind:
+			if ft.Kind() == reflect.Uint64 {
+				return nil, coderFixed64
+			}
+		case pref.DoubleKind:
+			if ft.Kind() == reflect.Float64 {
+				return nil, coderDouble
+			}
+		case pref.StringKind:
+			if ft.Kind() == reflect.String && strs.EnforceUTF8(fd) {
+				return nil, coderStringValidateUTF8
+			}
+			if ft.Kind() == reflect.String {
+				return nil, coderString
+			}
+			if ft.Kind() == reflect.Slice && ft.Elem().Kind() == reflect.Uint8 && strs.EnforceUTF8(fd) {
+				return nil, coderBytesValidateUTF8
+			}
+			if ft.Kind() == reflect.Slice && ft.Elem().Kind() == reflect.Uint8 {
+				return nil, coderBytes
+			}
+		case pref.BytesKind:
+			if ft.Kind() == reflect.String {
+				return nil, coderString
+			}
+			if ft.Kind() == reflect.Slice && ft.Elem().Kind() == reflect.Uint8 {
+				return nil, coderBytes
+			}
+		}
+	}
+	panic(fmt.Sprintf("invalid type: no encoder for %v %v %v/%v", fd.FullName(), fd.Cardinality(), fd.Kind(), ft))
+}
+
+// encoderFuncsForValue returns value functions for a field, used for
+// extension values and map encoding.
+func encoderFuncsForValue(fd pref.FieldDescriptor) valueCoderFuncs {
+	switch {
+	case fd.Cardinality() == pref.Repeated && !fd.IsPacked():
+		switch fd.Kind() {
+		case pref.BoolKind:
+			return coderBoolSliceValue
+		case pref.EnumKind:
+			return coderEnumSliceValue
+		case pref.Int32Kind:
+			return coderInt32SliceValue
+		case pref.Sint32Kind:
+			return coderSint32SliceValue
+		case pref.Uint32Kind:
+			return coderUint32SliceValue
+		case pref.Int64Kind:
+			return coderInt64SliceValue
+		case pref.Sint64Kind:
+			return coderSint64SliceValue
+		case pref.Uint64Kind:
+			return coderUint64SliceValue
+		case pref.Sfixed32Kind:
+			return coderSfixed32SliceValue
+		case pref.Fixed32Kind:
+			return coderFixed32SliceValue
+		case pref.FloatKind:
+			return coderFloatSliceValue
+		case pref.Sfixed64Kind:
+			return coderSfixed64SliceValue
+		case pref.Fixed64Kind:
+			return coderFixed64SliceValue
+		case pref.DoubleKind:
+			return coderDoubleSliceValue
+		case pref.StringKind:
+			// We don't have a UTF-8 validating coder for repeated string fields.
+			// Value coders are used for extensions and maps.
+			// Extensions are never proto3, and maps never contain lists.
+			return coderStringSliceValue
+		case pref.BytesKind:
+			return coderBytesSliceValue
+		case pref.MessageKind:
+			return coderMessageSliceValue
+		case pref.GroupKind:
+			return coderGroupSliceValue
+		}
+	case fd.Cardinality() == pref.Repeated && fd.IsPacked():
+		switch fd.Kind() {
+		case pref.BoolKind:
+			return coderBoolPackedSliceValue
+		case pref.EnumKind:
+			return coderEnumPackedSliceValue
+		case pref.Int32Kind:
+			return coderInt32PackedSliceValue
+		case pref.Sint32Kind:
+			return coderSint32PackedSliceValue
+		case pref.Uint32Kind:
+			return coderUint32PackedSliceValue
+		case pref.Int64Kind:
+			return coderInt64PackedSliceValue
+		case pref.Sint64Kind:
+			return coderSint64PackedSliceValue
+		case pref.Uint64Kind:
+			return coderUint64PackedSliceValue
+		case pref.Sfixed32Kind:
+			return coderSfixed32PackedSliceValue
+		case pref.Fixed32Kind:
+			return coderFixed32PackedSliceValue
+		case pref.FloatKind:
+			return coderFloatPackedSliceValue
+		case pref.Sfixed64Kind:
+			return coderSfixed64PackedSliceValue
+		case pref.Fixed64Kind:
+			return coderFixed64PackedSliceValue
+		case pref.DoubleKind:
+			return coderDoublePackedSliceValue
+		}
+	default:
+		switch fd.Kind() {
+		default:
+		case pref.BoolKind:
+			return coderBoolValue
+		case pref.EnumKind:
+			return coderEnumValue
+		case pref.Int32Kind:
+			return coderInt32Value
+		case pref.Sint32Kind:
+			return coderSint32Value
+		case pref.Uint32Kind:
+			return coderUint32Value
+		case pref.Int64Kind:
+			return coderInt64Value
+		case pref.Sint64Kind:
+			return coderSint64Value
+		case pref.Uint64Kind:
+			return coderUint64Value
+		case pref.Sfixed32Kind:
+			return coderSfixed32Value
+		case pref.Fixed32Kind:
+			return coderFixed32Value
+		case pref.FloatKind:
+			return coderFloatValue
+		case pref.Sfixed64Kind:
+			return coderSfixed64Value
+		case pref.Fixed64Kind:
+			return coderFixed64Value
+		case pref.DoubleKind:
+			return coderDoubleValue
+		case pref.StringKind:
+			if strs.EnforceUTF8(fd) {
+				return coderStringValueValidateUTF8
+			}
+			return coderStringValue
+		case pref.BytesKind:
+			return coderBytesValue
+		case pref.MessageKind:
+			return coderMessageValue
+		case pref.GroupKind:
+			return coderGroupValue
+		}
+	}
+	panic(fmt.Sprintf("invalid field: no encoder for %v %v %v", fd.FullName(), fd.Cardinality(), fd.Kind()))
+}

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

@@ -0,0 +1,17 @@
+// Copyright 2019 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build !purego,!appengine
+
+package impl
+
+// When using unsafe pointers, we can just treat enum values as int32s.
+
+var (
+	coderEnumNoZero      = coderInt32NoZero
+	coderEnum            = coderInt32
+	coderEnumPtr         = coderInt32Ptr
+	coderEnumSlice       = coderInt32Slice
+	coderEnumPackedSlice = coderInt32PackedSlice
+)

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

@@ -0,0 +1,467 @@
+// Copyright 2018 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package impl
+
+import (
+	"fmt"
+	"reflect"
+
+	pref "google.golang.org/protobuf/reflect/protoreflect"
+)
+
+// unwrapper unwraps the value to the underlying value.
+// This is implemented by List and Map.
+type unwrapper interface {
+	protoUnwrap() interface{}
+}
+
+// A Converter coverts to/from Go reflect.Value types and protobuf protoreflect.Value types.
+type Converter interface {
+	// PBValueOf converts a reflect.Value to a protoreflect.Value.
+	PBValueOf(reflect.Value) pref.Value
+
+	// GoValueOf converts a protoreflect.Value to a reflect.Value.
+	GoValueOf(pref.Value) reflect.Value
+
+	// IsValidPB returns whether a protoreflect.Value is compatible with this type.
+	IsValidPB(pref.Value) bool
+
+	// IsValidGo returns whether a reflect.Value is compatible with this type.
+	IsValidGo(reflect.Value) bool
+
+	// New returns a new field value.
+	// For scalars, it returns the default value of the field.
+	// For composite types, it returns a new mutable value.
+	New() pref.Value
+
+	// Zero returns a new field value.
+	// For scalars, it returns the default value of the field.
+	// For composite types, it returns an immutable, empty value.
+	Zero() pref.Value
+}
+
+// NewConverter matches a Go type with a protobuf field and returns a Converter
+// that converts between the two. Enums must be a named int32 kind that
+// implements protoreflect.Enum, and messages must be pointer to a named
+// struct type that implements protoreflect.ProtoMessage.
+//
+// This matcher deliberately supports a wider range of Go types than what
+// protoc-gen-go historically generated to be able to automatically wrap some
+// v1 messages generated by other forks of protoc-gen-go.
+func NewConverter(t reflect.Type, fd pref.FieldDescriptor) Converter {
+	switch {
+	case fd.IsList():
+		return newListConverter(t, fd)
+	case fd.IsMap():
+		return newMapConverter(t, fd)
+	default:
+		return newSingularConverter(t, fd)
+	}
+	panic(fmt.Sprintf("invalid Go type %v for field %v", t, fd.FullName()))
+}
+
+var (
+	boolType    = reflect.TypeOf(bool(false))
+	int32Type   = reflect.TypeOf(int32(0))
+	int64Type   = reflect.TypeOf(int64(0))
+	uint32Type  = reflect.TypeOf(uint32(0))
+	uint64Type  = reflect.TypeOf(uint64(0))
+	float32Type = reflect.TypeOf(float32(0))
+	float64Type = reflect.TypeOf(float64(0))
+	stringType  = reflect.TypeOf(string(""))
+	bytesType   = reflect.TypeOf([]byte(nil))
+	byteType    = reflect.TypeOf(byte(0))
+)
+
+var (
+	boolZero    = pref.ValueOfBool(false)
+	int32Zero   = pref.ValueOfInt32(0)
+	int64Zero   = pref.ValueOfInt64(0)
+	uint32Zero  = pref.ValueOfUint32(0)
+	uint64Zero  = pref.ValueOfUint64(0)
+	float32Zero = pref.ValueOfFloat32(0)
+	float64Zero = pref.ValueOfFloat64(0)
+	stringZero  = pref.ValueOfString("")
+	bytesZero   = pref.ValueOfBytes(nil)
+)
+
+func newSingularConverter(t reflect.Type, fd pref.FieldDescriptor) Converter {
+	defVal := func(fd pref.FieldDescriptor, zero pref.Value) pref.Value {
+		if fd.Cardinality() == pref.Repeated {
+			// Default isn't defined for repeated fields.
+			return zero
+		}
+		return fd.Default()
+	}
+	switch fd.Kind() {
+	case pref.BoolKind:
+		if t.Kind() == reflect.Bool {
+			return &boolConverter{t, defVal(fd, boolZero)}
+		}
+	case pref.Int32Kind, pref.Sint32Kind, pref.Sfixed32Kind:
+		if t.Kind() == reflect.Int32 {
+			return &int32Converter{t, defVal(fd, int32Zero)}
+		}
+	case pref.Int64Kind, pref.Sint64Kind, pref.Sfixed64Kind:
+		if t.Kind() == reflect.Int64 {
+			return &int64Converter{t, defVal(fd, int64Zero)}
+		}
+	case pref.Uint32Kind, pref.Fixed32Kind:
+		if t.Kind() == reflect.Uint32 {
+			return &uint32Converter{t, defVal(fd, uint32Zero)}
+		}
+	case pref.Uint64Kind, pref.Fixed64Kind:
+		if t.Kind() == reflect.Uint64 {
+			return &uint64Converter{t, defVal(fd, uint64Zero)}
+		}
+	case pref.FloatKind:
+		if t.Kind() == reflect.Float32 {
+			return &float32Converter{t, defVal(fd, float32Zero)}
+		}
+	case pref.DoubleKind:
+		if t.Kind() == reflect.Float64 {
+			return &float64Converter{t, defVal(fd, float64Zero)}
+		}
+	case pref.StringKind:
+		if t.Kind() == reflect.String || (t.Kind() == reflect.Slice && t.Elem() == byteType) {
+			return &stringConverter{t, defVal(fd, stringZero)}
+		}
+	case pref.BytesKind:
+		if t.Kind() == reflect.String || (t.Kind() == reflect.Slice && t.Elem() == byteType) {
+			return &bytesConverter{t, defVal(fd, bytesZero)}
+		}
+	case pref.EnumKind:
+		// Handle enums, which must be a named int32 type.
+		if t.Kind() == reflect.Int32 {
+			return newEnumConverter(t, fd)
+		}
+	case pref.MessageKind, pref.GroupKind:
+		return newMessageConverter(t)
+	}
+	panic(fmt.Sprintf("invalid Go type %v for field %v", t, fd.FullName()))
+}
+
+type boolConverter struct {
+	goType reflect.Type
+	def    pref.Value
+}
+
+func (c *boolConverter) PBValueOf(v reflect.Value) pref.Value {
+	if v.Type() != c.goType {
+		panic(fmt.Sprintf("invalid type: got %v, want %v", v.Type(), c.goType))
+	}
+	return pref.ValueOfBool(v.Bool())
+}
+func (c *boolConverter) GoValueOf(v pref.Value) reflect.Value {
+	return reflect.ValueOf(v.Bool()).Convert(c.goType)
+}
+func (c *boolConverter) IsValidPB(v pref.Value) bool {
+	_, ok := v.Interface().(bool)
+	return ok
+}
+func (c *boolConverter) IsValidGo(v reflect.Value) bool {
+	return v.IsValid() && v.Type() == c.goType
+}
+func (c *boolConverter) New() pref.Value  { return c.def }
+func (c *boolConverter) Zero() pref.Value { return c.def }
+
+type int32Converter struct {
+	goType reflect.Type
+	def    pref.Value
+}
+
+func (c *int32Converter) PBValueOf(v reflect.Value) pref.Value {
+	if v.Type() != c.goType {
+		panic(fmt.Sprintf("invalid type: got %v, want %v", v.Type(), c.goType))
+	}
+	return pref.ValueOfInt32(int32(v.Int()))
+}
+func (c *int32Converter) GoValueOf(v pref.Value) reflect.Value {
+	return reflect.ValueOf(int32(v.Int())).Convert(c.goType)
+}
+func (c *int32Converter) IsValidPB(v pref.Value) bool {
+	_, ok := v.Interface().(int32)
+	return ok
+}
+func (c *int32Converter) IsValidGo(v reflect.Value) bool {
+	return v.IsValid() && v.Type() == c.goType
+}
+func (c *int32Converter) New() pref.Value  { return c.def }
+func (c *int32Converter) Zero() pref.Value { return c.def }
+
+type int64Converter struct {
+	goType reflect.Type
+	def    pref.Value
+}
+
+func (c *int64Converter) PBValueOf(v reflect.Value) pref.Value {
+	if v.Type() != c.goType {
+		panic(fmt.Sprintf("invalid type: got %v, want %v", v.Type(), c.goType))
+	}
+	return pref.ValueOfInt64(int64(v.Int()))
+}
+func (c *int64Converter) GoValueOf(v pref.Value) reflect.Value {
+	return reflect.ValueOf(int64(v.Int())).Convert(c.goType)
+}
+func (c *int64Converter) IsValidPB(v pref.Value) bool {
+	_, ok := v.Interface().(int64)
+	return ok
+}
+func (c *int64Converter) IsValidGo(v reflect.Value) bool {
+	return v.IsValid() && v.Type() == c.goType
+}
+func (c *int64Converter) New() pref.Value  { return c.def }
+func (c *int64Converter) Zero() pref.Value { return c.def }
+
+type uint32Converter struct {
+	goType reflect.Type
+	def    pref.Value
+}
+
+func (c *uint32Converter) PBValueOf(v reflect.Value) pref.Value {
+	if v.Type() != c.goType {
+		panic(fmt.Sprintf("invalid type: got %v, want %v", v.Type(), c.goType))
+	}
+	return pref.ValueOfUint32(uint32(v.Uint()))
+}
+func (c *uint32Converter) GoValueOf(v pref.Value) reflect.Value {
+	return reflect.ValueOf(uint32(v.Uint())).Convert(c.goType)
+}
+func (c *uint32Converter) IsValidPB(v pref.Value) bool {
+	_, ok := v.Interface().(uint32)
+	return ok
+}
+func (c *uint32Converter) IsValidGo(v reflect.Value) bool {
+	return v.IsValid() && v.Type() == c.goType
+}
+func (c *uint32Converter) New() pref.Value  { return c.def }
+func (c *uint32Converter) Zero() pref.Value { return c.def }
+
+type uint64Converter struct {
+	goType reflect.Type
+	def    pref.Value
+}
+
+func (c *uint64Converter) PBValueOf(v reflect.Value) pref.Value {
+	if v.Type() != c.goType {
+		panic(fmt.Sprintf("invalid type: got %v, want %v", v.Type(), c.goType))
+	}
+	return pref.ValueOfUint64(uint64(v.Uint()))
+}
+func (c *uint64Converter) GoValueOf(v pref.Value) reflect.Value {
+	return reflect.ValueOf(uint64(v.Uint())).Convert(c.goType)
+}
+func (c *uint64Converter) IsValidPB(v pref.Value) bool {
+	_, ok := v.Interface().(uint64)
+	return ok
+}
+func (c *uint64Converter) IsValidGo(v reflect.Value) bool {
+	return v.IsValid() && v.Type() == c.goType
+}
+func (c *uint64Converter) New() pref.Value  { return c.def }
+func (c *uint64Converter) Zero() pref.Value { return c.def }
+
+type float32Converter struct {
+	goType reflect.Type
+	def    pref.Value
+}
+
+func (c *float32Converter) PBValueOf(v reflect.Value) pref.Value {
+	if v.Type() != c.goType {
+		panic(fmt.Sprintf("invalid type: got %v, want %v", v.Type(), c.goType))
+	}
+	return pref.ValueOfFloat32(float32(v.Float()))
+}
+func (c *float32Converter) GoValueOf(v pref.Value) reflect.Value {
+	return reflect.ValueOf(float32(v.Float())).Convert(c.goType)
+}
+func (c *float32Converter) IsValidPB(v pref.Value) bool {
+	_, ok := v.Interface().(float32)
+	return ok
+}
+func (c *float32Converter) IsValidGo(v reflect.Value) bool {
+	return v.IsValid() && v.Type() == c.goType
+}
+func (c *float32Converter) New() pref.Value  { return c.def }
+func (c *float32Converter) Zero() pref.Value { return c.def }
+
+type float64Converter struct {
+	goType reflect.Type
+	def    pref.Value
+}
+
+func (c *float64Converter) PBValueOf(v reflect.Value) pref.Value {
+	if v.Type() != c.goType {
+		panic(fmt.Sprintf("invalid type: got %v, want %v", v.Type(), c.goType))
+	}
+	return pref.ValueOfFloat64(float64(v.Float()))
+}
+func (c *float64Converter) GoValueOf(v pref.Value) reflect.Value {
+	return reflect.ValueOf(float64(v.Float())).Convert(c.goType)
+}
+func (c *float64Converter) IsValidPB(v pref.Value) bool {
+	_, ok := v.Interface().(float64)
+	return ok
+}
+func (c *float64Converter) IsValidGo(v reflect.Value) bool {
+	return v.IsValid() && v.Type() == c.goType
+}
+func (c *float64Converter) New() pref.Value  { return c.def }
+func (c *float64Converter) Zero() pref.Value { return c.def }
+
+type stringConverter struct {
+	goType reflect.Type
+	def    pref.Value
+}
+
+func (c *stringConverter) PBValueOf(v reflect.Value) pref.Value {
+	if v.Type() != c.goType {
+		panic(fmt.Sprintf("invalid type: got %v, want %v", v.Type(), c.goType))
+	}
+	return pref.ValueOfString(v.Convert(stringType).String())
+}
+func (c *stringConverter) GoValueOf(v pref.Value) reflect.Value {
+	// pref.Value.String never panics, so we go through an interface
+	// conversion here to check the type.
+	s := v.Interface().(string)
+	if c.goType.Kind() == reflect.Slice && s == "" {
+		return reflect.Zero(c.goType) // ensure empty string is []byte(nil)
+	}
+	return reflect.ValueOf(s).Convert(c.goType)
+}
+func (c *stringConverter) IsValidPB(v pref.Value) bool {
+	_, ok := v.Interface().(string)
+	return ok
+}
+func (c *stringConverter) IsValidGo(v reflect.Value) bool {
+	return v.IsValid() && v.Type() == c.goType
+}
+func (c *stringConverter) New() pref.Value  { return c.def }
+func (c *stringConverter) Zero() pref.Value { return c.def }
+
+type bytesConverter struct {
+	goType reflect.Type
+	def    pref.Value
+}
+
+func (c *bytesConverter) PBValueOf(v reflect.Value) pref.Value {
+	if v.Type() != c.goType {
+		panic(fmt.Sprintf("invalid type: got %v, want %v", v.Type(), c.goType))
+	}
+	if c.goType.Kind() == reflect.String && v.Len() == 0 {
+		return pref.ValueOfBytes(nil) // ensure empty string is []byte(nil)
+	}
+	return pref.ValueOfBytes(v.Convert(bytesType).Bytes())
+}
+func (c *bytesConverter) GoValueOf(v pref.Value) reflect.Value {
+	return reflect.ValueOf(v.Bytes()).Convert(c.goType)
+}
+func (c *bytesConverter) IsValidPB(v pref.Value) bool {
+	_, ok := v.Interface().([]byte)
+	return ok
+}
+func (c *bytesConverter) IsValidGo(v reflect.Value) bool {
+	return v.IsValid() && v.Type() == c.goType
+}
+func (c *bytesConverter) New() pref.Value  { return c.def }
+func (c *bytesConverter) Zero() pref.Value { return c.def }
+
+type enumConverter struct {
+	goType reflect.Type
+	def    pref.Value
+}
+
+func newEnumConverter(goType reflect.Type, fd pref.FieldDescriptor) Converter {
+	var def pref.Value
+	if fd.Cardinality() == pref.Repeated {
+		def = pref.ValueOfEnum(fd.Enum().Values().Get(0).Number())
+	} else {
+		def = fd.Default()
+	}
+	return &enumConverter{goType, def}
+}
+
+func (c *enumConverter) PBValueOf(v reflect.Value) pref.Value {
+	if v.Type() != c.goType {
+		panic(fmt.Sprintf("invalid type: got %v, want %v", v.Type(), c.goType))
+	}
+	return pref.ValueOfEnum(pref.EnumNumber(v.Int()))
+}
+
+func (c *enumConverter) GoValueOf(v pref.Value) reflect.Value {
+	return reflect.ValueOf(v.Enum()).Convert(c.goType)
+}
+
+func (c *enumConverter) IsValidPB(v pref.Value) bool {
+	_, ok := v.Interface().(pref.EnumNumber)
+	return ok
+}
+
+func (c *enumConverter) IsValidGo(v reflect.Value) bool {
+	return v.IsValid() && v.Type() == c.goType
+}
+
+func (c *enumConverter) New() pref.Value {
+	return c.def
+}
+
+func (c *enumConverter) Zero() pref.Value {
+	return c.def
+}
+
+type messageConverter struct {
+	goType reflect.Type
+}
+
+func newMessageConverter(goType reflect.Type) Converter {
+	return &messageConverter{goType}
+}
+
+func (c *messageConverter) PBValueOf(v reflect.Value) pref.Value {
+	if v.Type() != c.goType {
+		panic(fmt.Sprintf("invalid type: got %v, want %v", v.Type(), c.goType))
+	}
+	if m, ok := v.Interface().(pref.ProtoMessage); ok {
+		return pref.ValueOfMessage(m.ProtoReflect())
+	}
+	return pref.ValueOfMessage(legacyWrapMessage(v))
+}
+
+func (c *messageConverter) GoValueOf(v pref.Value) reflect.Value {
+	m := v.Message()
+	var rv reflect.Value
+	if u, ok := m.(unwrapper); ok {
+		rv = reflect.ValueOf(u.protoUnwrap())
+	} else {
+		rv = reflect.ValueOf(m.Interface())
+	}
+	if rv.Type() != c.goType {
+		panic(fmt.Sprintf("invalid type: got %v, want %v", rv.Type(), c.goType))
+	}
+	return rv
+}
+
+func (c *messageConverter) IsValidPB(v pref.Value) bool {
+	m := v.Message()
+	var rv reflect.Value
+	if u, ok := m.(unwrapper); ok {
+		rv = reflect.ValueOf(u.protoUnwrap())
+	} else {
+		rv = reflect.ValueOf(m.Interface())
+	}
+	return rv.Type() == c.goType
+}
+
+func (c *messageConverter) IsValidGo(v reflect.Value) bool {
+	return v.IsValid() && v.Type() == c.goType
+}
+
+func (c *messageConverter) New() pref.Value {
+	return c.PBValueOf(reflect.New(c.goType.Elem()))
+}
+
+func (c *messageConverter) Zero() pref.Value {
+	return c.PBValueOf(reflect.Zero(c.goType))
+}

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

@@ -0,0 +1,141 @@
+// Copyright 2018 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package impl
+
+import (
+	"fmt"
+	"reflect"
+
+	pref "google.golang.org/protobuf/reflect/protoreflect"
+)
+
+func newListConverter(t reflect.Type, fd pref.FieldDescriptor) Converter {
+	switch {
+	case t.Kind() == reflect.Ptr && t.Elem().Kind() == reflect.Slice:
+		return &listPtrConverter{t, newSingularConverter(t.Elem().Elem(), fd)}
+	case t.Kind() == reflect.Slice:
+		return &listConverter{t, newSingularConverter(t.Elem(), fd)}
+	}
+	panic(fmt.Sprintf("invalid Go type %v for field %v", t, fd.FullName()))
+}
+
+type listConverter struct {
+	goType reflect.Type // []T
+	c      Converter
+}
+
+func (c *listConverter) PBValueOf(v reflect.Value) pref.Value {
+	if v.Type() != c.goType {
+		panic(fmt.Sprintf("invalid type: got %v, want %v", v.Type(), c.goType))
+	}
+	pv := reflect.New(c.goType)
+	pv.Elem().Set(v)
+	return pref.ValueOfList(&listReflect{pv, c.c})
+}
+
+func (c *listConverter) GoValueOf(v pref.Value) reflect.Value {
+	rv := v.List().(*listReflect).v
+	if rv.IsNil() {
+		return reflect.Zero(c.goType)
+	}
+	return rv.Elem()
+}
+
+func (c *listConverter) IsValidPB(v pref.Value) bool {
+	list, ok := v.Interface().(*listReflect)
+	if !ok {
+		return false
+	}
+	return list.v.Type().Elem() == c.goType
+}
+
+func (c *listConverter) IsValidGo(v reflect.Value) bool {
+	return v.IsValid() && v.Type() == c.goType
+}
+
+func (c *listConverter) New() pref.Value {
+	return pref.ValueOfList(&listReflect{reflect.New(c.goType), c.c})
+}
+
+func (c *listConverter) Zero() pref.Value {
+	return pref.ValueOfList(&listReflect{reflect.Zero(reflect.PtrTo(c.goType)), c.c})
+}
+
+type listPtrConverter struct {
+	goType reflect.Type // *[]T
+	c      Converter
+}
+
+func (c *listPtrConverter) PBValueOf(v reflect.Value) pref.Value {
+	if v.Type() != c.goType {
+		panic(fmt.Sprintf("invalid type: got %v, want %v", v.Type(), c.goType))
+	}
+	return pref.ValueOfList(&listReflect{v, c.c})
+}
+
+func (c *listPtrConverter) GoValueOf(v pref.Value) reflect.Value {
+	return v.List().(*listReflect).v
+}
+
+func (c *listPtrConverter) IsValidPB(v pref.Value) bool {
+	list, ok := v.Interface().(*listReflect)
+	if !ok {
+		return false
+	}
+	return list.v.Type() == c.goType
+}
+
+func (c *listPtrConverter) IsValidGo(v reflect.Value) bool {
+	return v.IsValid() && v.Type() == c.goType
+}
+
+func (c *listPtrConverter) New() pref.Value {
+	return c.PBValueOf(reflect.New(c.goType.Elem()))
+}
+
+func (c *listPtrConverter) Zero() pref.Value {
+	return c.PBValueOf(reflect.Zero(c.goType))
+}
+
+type listReflect struct {
+	v    reflect.Value // *[]T
+	conv Converter
+}
+
+func (ls *listReflect) Len() int {
+	if ls.v.IsNil() {
+		return 0
+	}
+	return ls.v.Elem().Len()
+}
+func (ls *listReflect) Get(i int) pref.Value {
+	return ls.conv.PBValueOf(ls.v.Elem().Index(i))
+}
+func (ls *listReflect) Set(i int, v pref.Value) {
+	ls.v.Elem().Index(i).Set(ls.conv.GoValueOf(v))
+}
+func (ls *listReflect) Append(v pref.Value) {
+	ls.v.Elem().Set(reflect.Append(ls.v.Elem(), ls.conv.GoValueOf(v)))
+}
+func (ls *listReflect) AppendMutable() pref.Value {
+	if _, ok := ls.conv.(*messageConverter); !ok {
+		panic("invalid AppendMutable on list with non-message type")
+	}
+	v := ls.NewElement()
+	ls.Append(v)
+	return v
+}
+func (ls *listReflect) Truncate(i int) {
+	ls.v.Elem().Set(ls.v.Elem().Slice(0, i))
+}
+func (ls *listReflect) NewElement() pref.Value {
+	return ls.conv.New()
+}
+func (ls *listReflect) IsValid() bool {
+	return !ls.v.IsNil()
+}
+func (ls *listReflect) protoUnwrap() interface{} {
+	return ls.v.Interface()
+}

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

@@ -0,0 +1,121 @@
+// Copyright 2018 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package impl
+
+import (
+	"fmt"
+	"reflect"
+
+	pref "google.golang.org/protobuf/reflect/protoreflect"
+)
+
+type mapConverter struct {
+	goType           reflect.Type // map[K]V
+	keyConv, valConv Converter
+}
+
+func newMapConverter(t reflect.Type, fd pref.FieldDescriptor) *mapConverter {
+	if t.Kind() != reflect.Map {
+		panic(fmt.Sprintf("invalid Go type %v for field %v", t, fd.FullName()))
+	}
+	return &mapConverter{
+		goType:  t,
+		keyConv: newSingularConverter(t.Key(), fd.MapKey()),
+		valConv: newSingularConverter(t.Elem(), fd.MapValue()),
+	}
+}
+
+func (c *mapConverter) PBValueOf(v reflect.Value) pref.Value {
+	if v.Type() != c.goType {
+		panic(fmt.Sprintf("invalid type: got %v, want %v", v.Type(), c.goType))
+	}
+	return pref.ValueOfMap(&mapReflect{v, c.keyConv, c.valConv})
+}
+
+func (c *mapConverter) GoValueOf(v pref.Value) reflect.Value {
+	return v.Map().(*mapReflect).v
+}
+
+func (c *mapConverter) IsValidPB(v pref.Value) bool {
+	mapv, ok := v.Interface().(*mapReflect)
+	if !ok {
+		return false
+	}
+	return mapv.v.Type() == c.goType
+}
+
+func (c *mapConverter) IsValidGo(v reflect.Value) bool {
+	return v.IsValid() && v.Type() == c.goType
+}
+
+func (c *mapConverter) New() pref.Value {
+	return c.PBValueOf(reflect.MakeMap(c.goType))
+}
+
+func (c *mapConverter) Zero() pref.Value {
+	return c.PBValueOf(reflect.Zero(c.goType))
+}
+
+type mapReflect struct {
+	v       reflect.Value // map[K]V
+	keyConv Converter
+	valConv Converter
+}
+
+func (ms *mapReflect) Len() int {
+	return ms.v.Len()
+}
+func (ms *mapReflect) Has(k pref.MapKey) bool {
+	rk := ms.keyConv.GoValueOf(k.Value())
+	rv := ms.v.MapIndex(rk)
+	return rv.IsValid()
+}
+func (ms *mapReflect) Get(k pref.MapKey) pref.Value {
+	rk := ms.keyConv.GoValueOf(k.Value())
+	rv := ms.v.MapIndex(rk)
+	if !rv.IsValid() {
+		return pref.Value{}
+	}
+	return ms.valConv.PBValueOf(rv)
+}
+func (ms *mapReflect) Set(k pref.MapKey, v pref.Value) {
+	rk := ms.keyConv.GoValueOf(k.Value())
+	rv := ms.valConv.GoValueOf(v)
+	ms.v.SetMapIndex(rk, rv)
+}
+func (ms *mapReflect) Clear(k pref.MapKey) {
+	rk := ms.keyConv.GoValueOf(k.Value())
+	ms.v.SetMapIndex(rk, reflect.Value{})
+}
+func (ms *mapReflect) Mutable(k pref.MapKey) pref.Value {
+	if _, ok := ms.valConv.(*messageConverter); !ok {
+		panic("invalid Mutable on map with non-message value type")
+	}
+	v := ms.Get(k)
+	if !v.IsValid() {
+		v = ms.NewValue()
+		ms.Set(k, v)
+	}
+	return v
+}
+func (ms *mapReflect) Range(f func(pref.MapKey, pref.Value) bool) {
+	iter := mapRange(ms.v)
+	for iter.Next() {
+		k := ms.keyConv.PBValueOf(iter.Key()).MapKey()
+		v := ms.valConv.PBValueOf(iter.Value())
+		if !f(k, v) {
+			return
+		}
+	}
+}
+func (ms *mapReflect) NewValue() pref.Value {
+	return ms.valConv.New()
+}
+func (ms *mapReflect) IsValid() bool {
+	return !ms.v.IsNil()
+}
+func (ms *mapReflect) protoUnwrap() interface{} {
+	return ms.v.Interface()
+}

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

@@ -0,0 +1,274 @@
+// Copyright 2019 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package impl
+
+import (
+	"math/bits"
+
+	"google.golang.org/protobuf/encoding/protowire"
+	"google.golang.org/protobuf/internal/errors"
+	"google.golang.org/protobuf/internal/flags"
+	"google.golang.org/protobuf/proto"
+	"google.golang.org/protobuf/reflect/protoreflect"
+	preg "google.golang.org/protobuf/reflect/protoregistry"
+	"google.golang.org/protobuf/runtime/protoiface"
+	piface "google.golang.org/protobuf/runtime/protoiface"
+)
+
+type unmarshalOptions struct {
+	flags    protoiface.UnmarshalInputFlags
+	resolver interface {
+		FindExtensionByName(field protoreflect.FullName) (protoreflect.ExtensionType, error)
+		FindExtensionByNumber(message protoreflect.FullName, field protoreflect.FieldNumber) (protoreflect.ExtensionType, error)
+	}
+}
+
+func (o unmarshalOptions) Options() proto.UnmarshalOptions {
+	return proto.UnmarshalOptions{
+		Merge:          true,
+		AllowPartial:   true,
+		DiscardUnknown: o.DiscardUnknown(),
+		Resolver:       o.resolver,
+	}
+}
+
+func (o unmarshalOptions) DiscardUnknown() bool { return o.flags&piface.UnmarshalDiscardUnknown != 0 }
+
+func (o unmarshalOptions) IsDefault() bool {
+	return o.flags == 0 && o.resolver == preg.GlobalTypes
+}
+
+var lazyUnmarshalOptions = unmarshalOptions{
+	resolver: preg.GlobalTypes,
+}
+
+type unmarshalOutput struct {
+	n           int // number of bytes consumed
+	initialized bool
+}
+
+// unmarshal is protoreflect.Methods.Unmarshal.
+func (mi *MessageInfo) unmarshal(in piface.UnmarshalInput) (piface.UnmarshalOutput, error) {
+	var p pointer
+	if ms, ok := in.Message.(*messageState); ok {
+		p = ms.pointer()
+	} else {
+		p = in.Message.(*messageReflectWrapper).pointer()
+	}
+	out, err := mi.unmarshalPointer(in.Buf, p, 0, unmarshalOptions{
+		flags:    in.Flags,
+		resolver: in.Resolver,
+	})
+	var flags piface.UnmarshalOutputFlags
+	if out.initialized {
+		flags |= piface.UnmarshalInitialized
+	}
+	return piface.UnmarshalOutput{
+		Flags: flags,
+	}, err
+}
+
+// errUnknown is returned during unmarshaling to indicate a parse error that
+// should result in a field being placed in the unknown fields section (for example,
+// when the wire type doesn't match) as opposed to the entire unmarshal operation
+// failing (for example, when a field extends past the available input).
+//
+// This is a sentinel error which should never be visible to the user.
+var errUnknown = errors.New("unknown")
+
+func (mi *MessageInfo) unmarshalPointer(b []byte, p pointer, groupTag protowire.Number, opts unmarshalOptions) (out unmarshalOutput, err error) {
+	mi.init()
+	if flags.ProtoLegacy && mi.isMessageSet {
+		return unmarshalMessageSet(mi, b, p, opts)
+	}
+	initialized := true
+	var requiredMask uint64
+	var exts *map[int32]ExtensionField
+	start := len(b)
+	for len(b) > 0 {
+		// Parse the tag (field number and wire type).
+		var tag uint64
+		if b[0] < 0x80 {
+			tag = uint64(b[0])
+			b = b[1:]
+		} else if len(b) >= 2 && b[1] < 128 {
+			tag = uint64(b[0]&0x7f) + uint64(b[1])<<7
+			b = b[2:]
+		} else {
+			var n int
+			tag, n = protowire.ConsumeVarint(b)
+			if n < 0 {
+				return out, protowire.ParseError(n)
+			}
+			b = b[n:]
+		}
+		var num protowire.Number
+		if n := tag >> 3; n < uint64(protowire.MinValidNumber) || n > uint64(protowire.MaxValidNumber) {
+			return out, errors.New("invalid field number")
+		} else {
+			num = protowire.Number(n)
+		}
+		wtyp := protowire.Type(tag & 7)
+
+		if wtyp == protowire.EndGroupType {
+			if num != groupTag {
+				return out, errors.New("mismatching end group marker")
+			}
+			groupTag = 0
+			break
+		}
+
+		var f *coderFieldInfo
+		if int(num) < len(mi.denseCoderFields) {
+			f = mi.denseCoderFields[num]
+		} else {
+			f = mi.coderFields[num]
+		}
+		var n int
+		err := errUnknown
+		switch {
+		case f != nil:
+			if f.funcs.unmarshal == nil {
+				break
+			}
+			var o unmarshalOutput
+			o, err = f.funcs.unmarshal(b, p.Apply(f.offset), wtyp, f, opts)
+			n = o.n
+			if err != nil {
+				break
+			}
+			requiredMask |= f.validation.requiredBit
+			if f.funcs.isInit != nil && !o.initialized {
+				initialized = false
+			}
+		default:
+			// Possible extension.
+			if exts == nil && mi.extensionOffset.IsValid() {
+				exts = p.Apply(mi.extensionOffset).Extensions()
+				if *exts == nil {
+					*exts = make(map[int32]ExtensionField)
+				}
+			}
+			if exts == nil {
+				break
+			}
+			var o unmarshalOutput
+			o, err = mi.unmarshalExtension(b, num, wtyp, *exts, opts)
+			if err != nil {
+				break
+			}
+			n = o.n
+			if !o.initialized {
+				initialized = false
+			}
+		}
+		if err != nil {
+			if err != errUnknown {
+				return out, err
+			}
+			n = protowire.ConsumeFieldValue(num, wtyp, b)
+			if n < 0 {
+				return out, protowire.ParseError(n)
+			}
+			if !opts.DiscardUnknown() && mi.unknownOffset.IsValid() {
+				u := p.Apply(mi.unknownOffset).Bytes()
+				*u = protowire.AppendTag(*u, num, wtyp)
+				*u = append(*u, b[:n]...)
+			}
+		}
+		b = b[n:]
+	}
+	if groupTag != 0 {
+		return out, errors.New("missing end group marker")
+	}
+	if mi.numRequiredFields > 0 && bits.OnesCount64(requiredMask) != int(mi.numRequiredFields) {
+		initialized = false
+	}
+	if initialized {
+		out.initialized = true
+	}
+	out.n = start - len(b)
+	return out, nil
+}
+
+func (mi *MessageInfo) unmarshalExtension(b []byte, num protowire.Number, wtyp protowire.Type, exts map[int32]ExtensionField, opts unmarshalOptions) (out unmarshalOutput, err error) {
+	x := exts[int32(num)]
+	xt := x.Type()
+	if xt == nil {
+		var err error
+		xt, err = opts.resolver.FindExtensionByNumber(mi.Desc.FullName(), num)
+		if err != nil {
+			if err == preg.NotFound {
+				return out, errUnknown
+			}
+			return out, errors.New("%v: unable to resolve extension %v: %v", mi.Desc.FullName(), num, err)
+		}
+	}
+	xi := getExtensionFieldInfo(xt)
+	if xi.funcs.unmarshal == nil {
+		return out, errUnknown
+	}
+	if flags.LazyUnmarshalExtensions {
+		if opts.IsDefault() && x.canLazy(xt) {
+			out, valid := skipExtension(b, xi, num, wtyp, opts)
+			switch valid {
+			case ValidationValid:
+				if out.initialized {
+					x.appendLazyBytes(xt, xi, num, wtyp, b[:out.n])
+					exts[int32(num)] = x
+					return out, nil
+				}
+			case ValidationInvalid:
+				return out, errors.New("invalid wire format")
+			case ValidationUnknown:
+			}
+		}
+	}
+	ival := x.Value()
+	if !ival.IsValid() && xi.unmarshalNeedsValue {
+		// Create a new message, list, or map value to fill in.
+		// For enums, create a prototype value to let the unmarshal func know the
+		// concrete type.
+		ival = xt.New()
+	}
+	v, out, err := xi.funcs.unmarshal(b, ival, num, wtyp, opts)
+	if err != nil {
+		return out, err
+	}
+	if xi.funcs.isInit == nil {
+		out.initialized = true
+	}
+	x.Set(xt, v)
+	exts[int32(num)] = x
+	return out, nil
+}
+
+func skipExtension(b []byte, xi *extensionFieldInfo, num protowire.Number, wtyp protowire.Type, opts unmarshalOptions) (out unmarshalOutput, _ ValidationStatus) {
+	if xi.validation.mi == nil {
+		return out, ValidationUnknown
+	}
+	xi.validation.mi.init()
+	switch xi.validation.typ {
+	case validationTypeMessage:
+		if wtyp != protowire.BytesType {
+			return out, ValidationUnknown
+		}
+		v, n := protowire.ConsumeBytes(b)
+		if n < 0 {
+			return out, ValidationUnknown
+		}
+		out, st := xi.validation.mi.validate(v, 0, opts)
+		out.n = n
+		return out, st
+	case validationTypeGroup:
+		if wtyp != protowire.StartGroupType {
+			return out, ValidationUnknown
+		}
+		out, st := xi.validation.mi.validate(b, num, opts)
+		return out, st
+	default:
+		return out, ValidationUnknown
+	}
+}

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

@@ -0,0 +1,199 @@
+// Copyright 2019 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package impl
+
+import (
+	"math"
+	"sort"
+	"sync/atomic"
+
+	"google.golang.org/protobuf/internal/flags"
+	proto "google.golang.org/protobuf/proto"
+	piface "google.golang.org/protobuf/runtime/protoiface"
+)
+
+type marshalOptions struct {
+	flags piface.MarshalInputFlags
+}
+
+func (o marshalOptions) Options() proto.MarshalOptions {
+	return proto.MarshalOptions{
+		AllowPartial:  true,
+		Deterministic: o.Deterministic(),
+		UseCachedSize: o.UseCachedSize(),
+	}
+}
+
+func (o marshalOptions) Deterministic() bool { return o.flags&piface.MarshalDeterministic != 0 }
+func (o marshalOptions) UseCachedSize() bool { return o.flags&piface.MarshalUseCachedSize != 0 }
+
+// size is protoreflect.Methods.Size.
+func (mi *MessageInfo) size(in piface.SizeInput) piface.SizeOutput {
+	var p pointer
+	if ms, ok := in.Message.(*messageState); ok {
+		p = ms.pointer()
+	} else {
+		p = in.Message.(*messageReflectWrapper).pointer()
+	}
+	size := mi.sizePointer(p, marshalOptions{
+		flags: in.Flags,
+	})
+	return piface.SizeOutput{Size: size}
+}
+
+func (mi *MessageInfo) sizePointer(p pointer, opts marshalOptions) (size int) {
+	mi.init()
+	if p.IsNil() {
+		return 0
+	}
+	if opts.UseCachedSize() && mi.sizecacheOffset.IsValid() {
+		if size := atomic.LoadInt32(p.Apply(mi.sizecacheOffset).Int32()); size >= 0 {
+			return int(size)
+		}
+	}
+	return mi.sizePointerSlow(p, opts)
+}
+
+func (mi *MessageInfo) sizePointerSlow(p pointer, opts marshalOptions) (size int) {
+	if flags.ProtoLegacy && mi.isMessageSet {
+		size = sizeMessageSet(mi, p, opts)
+		if mi.sizecacheOffset.IsValid() {
+			atomic.StoreInt32(p.Apply(mi.sizecacheOffset).Int32(), int32(size))
+		}
+		return size
+	}
+	if mi.extensionOffset.IsValid() {
+		e := p.Apply(mi.extensionOffset).Extensions()
+		size += mi.sizeExtensions(e, opts)
+	}
+	for _, f := range mi.orderedCoderFields {
+		if f.funcs.size == nil {
+			continue
+		}
+		fptr := p.Apply(f.offset)
+		if f.isPointer && fptr.Elem().IsNil() {
+			continue
+		}
+		size += f.funcs.size(fptr, f, opts)
+	}
+	if mi.unknownOffset.IsValid() {
+		u := *p.Apply(mi.unknownOffset).Bytes()
+		size += len(u)
+	}
+	if mi.sizecacheOffset.IsValid() {
+		if size > math.MaxInt32 {
+			// The size is too large for the int32 sizecache field.
+			// We will need to recompute the size when encoding;
+			// unfortunately expensive, but better than invalid output.
+			atomic.StoreInt32(p.Apply(mi.sizecacheOffset).Int32(), -1)
+		} else {
+			atomic.StoreInt32(p.Apply(mi.sizecacheOffset).Int32(), int32(size))
+		}
+	}
+	return size
+}
+
+// marshal is protoreflect.Methods.Marshal.
+func (mi *MessageInfo) marshal(in piface.MarshalInput) (out piface.MarshalOutput, err error) {
+	var p pointer
+	if ms, ok := in.Message.(*messageState); ok {
+		p = ms.pointer()
+	} else {
+		p = in.Message.(*messageReflectWrapper).pointer()
+	}
+	b, err := mi.marshalAppendPointer(in.Buf, p, marshalOptions{
+		flags: in.Flags,
+	})
+	return piface.MarshalOutput{Buf: b}, err
+}
+
+func (mi *MessageInfo) marshalAppendPointer(b []byte, p pointer, opts marshalOptions) ([]byte, error) {
+	mi.init()
+	if p.IsNil() {
+		return b, nil
+	}
+	if flags.ProtoLegacy && mi.isMessageSet {
+		return marshalMessageSet(mi, b, p, opts)
+	}
+	var err error
+	// The old marshaler encodes extensions at beginning.
+	if mi.extensionOffset.IsValid() {
+		e := p.Apply(mi.extensionOffset).Extensions()
+		// TODO: Special handling for MessageSet?
+		b, err = mi.appendExtensions(b, e, opts)
+		if err != nil {
+			return b, err
+		}
+	}
+	for _, f := range mi.orderedCoderFields {
+		if f.funcs.marshal == nil {
+			continue
+		}
+		fptr := p.Apply(f.offset)
+		if f.isPointer && fptr.Elem().IsNil() {
+			continue
+		}
+		b, err = f.funcs.marshal(b, fptr, f, opts)
+		if err != nil {
+			return b, err
+		}
+	}
+	if mi.unknownOffset.IsValid() && !mi.isMessageSet {
+		u := *p.Apply(mi.unknownOffset).Bytes()
+		b = append(b, u...)
+	}
+	return b, nil
+}
+
+func (mi *MessageInfo) sizeExtensions(ext *map[int32]ExtensionField, opts marshalOptions) (n int) {
+	if ext == nil {
+		return 0
+	}
+	for _, x := range *ext {
+		xi := getExtensionFieldInfo(x.Type())
+		if xi.funcs.size == nil {
+			continue
+		}
+		n += xi.funcs.size(x.Value(), xi.tagsize, opts)
+	}
+	return n
+}
+
+func (mi *MessageInfo) appendExtensions(b []byte, ext *map[int32]ExtensionField, opts marshalOptions) ([]byte, error) {
+	if ext == nil {
+		return b, nil
+	}
+
+	switch len(*ext) {
+	case 0:
+		return b, nil
+	case 1:
+		// Fast-path for one extension: Don't bother sorting the keys.
+		var err error
+		for _, x := range *ext {
+			xi := getExtensionFieldInfo(x.Type())
+			b, err = xi.funcs.marshal(b, x.Value(), xi.wiretag, opts)
+		}
+		return b, err
+	default:
+		// Sort the keys to provide a deterministic encoding.
+		// Not sure this is required, but the old code does it.
+		keys := make([]int, 0, len(*ext))
+		for k := range *ext {
+			keys = append(keys, int(k))
+		}
+		sort.Ints(keys)
+		var err error
+		for _, k := range keys {
+			x := (*ext)[int32(k)]
+			xi := getExtensionFieldInfo(x.Type())
+			b, err = xi.funcs.marshal(b, x.Value(), xi.wiretag, opts)
+			if err != nil {
+				return b, err
+			}
+		}
+		return b, nil
+	}
+}

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

@@ -0,0 +1,21 @@
+// Copyright 2019 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package impl
+
+import (
+	"reflect"
+
+	pref "google.golang.org/protobuf/reflect/protoreflect"
+)
+
+type EnumInfo struct {
+	GoReflectType reflect.Type // int32 kind
+	Desc          pref.EnumDescriptor
+}
+
+func (t *EnumInfo) New(n pref.EnumNumber) pref.Enum {
+	return reflect.ValueOf(n).Convert(t.GoReflectType).Interface().(pref.Enum)
+}
+func (t *EnumInfo) Descriptor() pref.EnumDescriptor { return t.Desc }

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

@@ -0,0 +1,156 @@
+// Copyright 2019 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package impl
+
+import (
+	"reflect"
+	"sync"
+	"sync/atomic"
+
+	pref "google.golang.org/protobuf/reflect/protoreflect"
+	piface "google.golang.org/protobuf/runtime/protoiface"
+)
+
+// ExtensionInfo implements ExtensionType.
+//
+// This type contains a number of exported fields for legacy compatibility.
+// The only non-deprecated use of this type is through the methods of the
+// ExtensionType interface.
+type ExtensionInfo struct {
+	// An ExtensionInfo may exist in several stages of initialization.
+	//
+	// extensionInfoUninitialized: Some or all of the legacy exported
+	// fields may be set, but none of the unexported fields have been
+	// initialized. This is the starting state for an ExtensionInfo
+	// in legacy generated code.
+	//
+	// extensionInfoDescInit: The desc field is set, but other unexported fields
+	// may not be initialized. Legacy exported fields may or may not be set.
+	// This is the starting state for an ExtensionInfo in newly generated code.
+	//
+	// extensionInfoFullInit: The ExtensionInfo is fully initialized.
+	// This state is only entered after lazy initialization is complete.
+	init uint32
+	mu   sync.Mutex
+
+	goType reflect.Type
+	desc   extensionTypeDescriptor
+	conv   Converter
+	info   *extensionFieldInfo // for fast-path method implementations
+
+	// ExtendedType is a typed nil-pointer to the parent message type that
+	// is being extended. It is possible for this to be unpopulated in v2
+	// since the message may no longer implement the MessageV1 interface.
+	//
+	// Deprecated: Use the ExtendedType method instead.
+	ExtendedType piface.MessageV1
+
+	// ExtensionType is the zero value of the extension type.
+	//
+	// For historical reasons, reflect.TypeOf(ExtensionType) and the
+	// type returned by InterfaceOf may not be identical.
+	//
+	// Deprecated: Use InterfaceOf(xt.Zero()) instead.
+	ExtensionType interface{}
+
+	// Field is the field number of the extension.
+	//
+	// Deprecated: Use the Descriptor().Number method instead.
+	Field int32
+
+	// Name is the fully qualified name of extension.
+	//
+	// Deprecated: Use the Descriptor().FullName method instead.
+	Name string
+
+	// Tag is the protobuf struct tag used in the v1 API.
+	//
+	// Deprecated: Do not use.
+	Tag string
+
+	// Filename is the proto filename in which the extension is defined.
+	//
+	// Deprecated: Use Descriptor().ParentFile().Path() instead.
+	Filename string
+}
+
+// Stages of initialization: See the ExtensionInfo.init field.
+const (
+	extensionInfoUninitialized = 0
+	extensionInfoDescInit      = 1
+	extensionInfoFullInit      = 2
+)
+
+func InitExtensionInfo(xi *ExtensionInfo, xd pref.ExtensionDescriptor, goType reflect.Type) {
+	xi.goType = goType
+	xi.desc = extensionTypeDescriptor{xd, xi}
+	xi.init = extensionInfoDescInit
+}
+
+func (xi *ExtensionInfo) New() pref.Value {
+	return xi.lazyInit().New()
+}
+func (xi *ExtensionInfo) Zero() pref.Value {
+	return xi.lazyInit().Zero()
+}
+func (xi *ExtensionInfo) ValueOf(v interface{}) pref.Value {
+	return xi.lazyInit().PBValueOf(reflect.ValueOf(v))
+}
+func (xi *ExtensionInfo) InterfaceOf(v pref.Value) interface{} {
+	return xi.lazyInit().GoValueOf(v).Interface()
+}
+func (xi *ExtensionInfo) IsValidValue(v pref.Value) bool {
+	return xi.lazyInit().IsValidPB(v)
+}
+func (xi *ExtensionInfo) IsValidInterface(v interface{}) bool {
+	return xi.lazyInit().IsValidGo(reflect.ValueOf(v))
+}
+func (xi *ExtensionInfo) TypeDescriptor() pref.ExtensionTypeDescriptor {
+	if atomic.LoadUint32(&xi.init) < extensionInfoDescInit {
+		xi.lazyInitSlow()
+	}
+	return &xi.desc
+}
+
+func (xi *ExtensionInfo) lazyInit() Converter {
+	if atomic.LoadUint32(&xi.init) < extensionInfoFullInit {
+		xi.lazyInitSlow()
+	}
+	return xi.conv
+}
+
+func (xi *ExtensionInfo) lazyInitSlow() {
+	xi.mu.Lock()
+	defer xi.mu.Unlock()
+
+	if xi.init == extensionInfoFullInit {
+		return
+	}
+	defer atomic.StoreUint32(&xi.init, extensionInfoFullInit)
+
+	if xi.desc.ExtensionDescriptor == nil {
+		xi.initFromLegacy()
+	}
+	if !xi.desc.ExtensionDescriptor.IsPlaceholder() {
+		if xi.ExtensionType == nil {
+			xi.initToLegacy()
+		}
+		xi.conv = NewConverter(xi.goType, xi.desc.ExtensionDescriptor)
+		xi.info = makeExtensionFieldInfo(xi.desc.ExtensionDescriptor)
+		xi.info.validation = newValidationInfo(xi.desc.ExtensionDescriptor, xi.goType)
+	}
+}
+
+type extensionTypeDescriptor struct {
+	pref.ExtensionDescriptor
+	xi *ExtensionInfo
+}
+
+func (xtd *extensionTypeDescriptor) Type() pref.ExtensionType {
+	return xtd.xi
+}
+func (xtd *extensionTypeDescriptor) Descriptor() pref.ExtensionDescriptor {
+	return xtd.ExtensionDescriptor
+}

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

@@ -0,0 +1,219 @@
+// Copyright 2018 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package impl
+
+import (
+	"fmt"
+	"reflect"
+	"strings"
+	"sync"
+
+	"google.golang.org/protobuf/internal/filedesc"
+	"google.golang.org/protobuf/internal/strs"
+	"google.golang.org/protobuf/reflect/protoreflect"
+	pref "google.golang.org/protobuf/reflect/protoreflect"
+)
+
+// legacyEnumName returns the name of enums used in legacy code.
+// It is neither the protobuf full name nor the qualified Go name,
+// but rather an odd hybrid of both.
+func legacyEnumName(ed pref.EnumDescriptor) string {
+	var protoPkg string
+	enumName := string(ed.FullName())
+	if fd := ed.ParentFile(); fd != nil {
+		protoPkg = string(fd.Package())
+		enumName = strings.TrimPrefix(enumName, protoPkg+".")
+	}
+	if protoPkg == "" {
+		return strs.GoCamelCase(enumName)
+	}
+	return protoPkg + "." + strs.GoCamelCase(enumName)
+}
+
+// legacyWrapEnum wraps v as a protoreflect.Enum,
+// where v must be a int32 kind and not implement the v2 API already.
+func legacyWrapEnum(v reflect.Value) pref.Enum {
+	et := legacyLoadEnumType(v.Type())
+	return et.New(pref.EnumNumber(v.Int()))
+}
+
+var legacyEnumTypeCache sync.Map // map[reflect.Type]protoreflect.EnumType
+
+// legacyLoadEnumType dynamically loads a protoreflect.EnumType for t,
+// where t must be an int32 kind and not implement the v2 API already.
+func legacyLoadEnumType(t reflect.Type) pref.EnumType {
+	// Fast-path: check if a EnumType is cached for this concrete type.
+	if et, ok := legacyEnumTypeCache.Load(t); ok {
+		return et.(pref.EnumType)
+	}
+
+	// Slow-path: derive enum descriptor and initialize EnumType.
+	var et pref.EnumType
+	ed := LegacyLoadEnumDesc(t)
+	et = &legacyEnumType{
+		desc:   ed,
+		goType: t,
+	}
+	if et, ok := legacyEnumTypeCache.LoadOrStore(t, et); ok {
+		return et.(pref.EnumType)
+	}
+	return et
+}
+
+type legacyEnumType struct {
+	desc   pref.EnumDescriptor
+	goType reflect.Type
+	m      sync.Map // map[protoreflect.EnumNumber]proto.Enum
+}
+
+func (t *legacyEnumType) New(n pref.EnumNumber) pref.Enum {
+	if e, ok := t.m.Load(n); ok {
+		return e.(pref.Enum)
+	}
+	e := &legacyEnumWrapper{num: n, pbTyp: t, goTyp: t.goType}
+	t.m.Store(n, e)
+	return e
+}
+func (t *legacyEnumType) Descriptor() pref.EnumDescriptor {
+	return t.desc
+}
+
+type legacyEnumWrapper struct {
+	num   pref.EnumNumber
+	pbTyp pref.EnumType
+	goTyp reflect.Type
+}
+
+func (e *legacyEnumWrapper) Descriptor() pref.EnumDescriptor {
+	return e.pbTyp.Descriptor()
+}
+func (e *legacyEnumWrapper) Type() pref.EnumType {
+	return e.pbTyp
+}
+func (e *legacyEnumWrapper) Number() pref.EnumNumber {
+	return e.num
+}
+func (e *legacyEnumWrapper) ProtoReflect() pref.Enum {
+	return e
+}
+func (e *legacyEnumWrapper) protoUnwrap() interface{} {
+	v := reflect.New(e.goTyp).Elem()
+	v.SetInt(int64(e.num))
+	return v.Interface()
+}
+
+var (
+	_ pref.Enum = (*legacyEnumWrapper)(nil)
+	_ unwrapper = (*legacyEnumWrapper)(nil)
+)
+
+var legacyEnumDescCache sync.Map // map[reflect.Type]protoreflect.EnumDescriptor
+
+// LegacyLoadEnumDesc returns an EnumDescriptor derived from the Go type,
+// which must be an int32 kind and not implement the v2 API already.
+//
+// This is exported for testing purposes.
+func LegacyLoadEnumDesc(t reflect.Type) pref.EnumDescriptor {
+	// Fast-path: check if an EnumDescriptor is cached for this concrete type.
+	if ed, ok := legacyEnumDescCache.Load(t); ok {
+		return ed.(pref.EnumDescriptor)
+	}
+
+	// Slow-path: initialize EnumDescriptor from the raw descriptor.
+	ev := reflect.Zero(t).Interface()
+	if _, ok := ev.(pref.Enum); ok {
+		panic(fmt.Sprintf("%v already implements proto.Enum", t))
+	}
+	edV1, ok := ev.(enumV1)
+	if !ok {
+		return aberrantLoadEnumDesc(t)
+	}
+	b, idxs := edV1.EnumDescriptor()
+
+	var ed pref.EnumDescriptor
+	if len(idxs) == 1 {
+		ed = legacyLoadFileDesc(b).Enums().Get(idxs[0])
+	} else {
+		md := legacyLoadFileDesc(b).Messages().Get(idxs[0])
+		for _, i := range idxs[1 : len(idxs)-1] {
+			md = md.Messages().Get(i)
+		}
+		ed = md.Enums().Get(idxs[len(idxs)-1])
+	}
+	if ed, ok := legacyEnumDescCache.LoadOrStore(t, ed); ok {
+		return ed.(protoreflect.EnumDescriptor)
+	}
+	return ed
+}
+
+var aberrantEnumDescCache sync.Map // map[reflect.Type]protoreflect.EnumDescriptor
+
+// aberrantLoadEnumDesc returns an EnumDescriptor derived from the Go type,
+// which must not implement protoreflect.Enum or enumV1.
+//
+// If the type does not implement enumV1, then there is no reliable
+// way to derive the original protobuf type information.
+// We are unable to use the global enum registry since it is
+// unfortunately keyed by the protobuf full name, which we also do not know.
+// Thus, this produces some bogus enum descriptor based on the Go type name.
+func aberrantLoadEnumDesc(t reflect.Type) pref.EnumDescriptor {
+	// Fast-path: check if an EnumDescriptor is cached for this concrete type.
+	if ed, ok := aberrantEnumDescCache.Load(t); ok {
+		return ed.(pref.EnumDescriptor)
+	}
+
+	// Slow-path: construct a bogus, but unique EnumDescriptor.
+	ed := &filedesc.Enum{L2: new(filedesc.EnumL2)}
+	ed.L0.FullName = AberrantDeriveFullName(t) // e.g., github_com.user.repo.MyEnum
+	ed.L0.ParentFile = filedesc.SurrogateProto3
+	ed.L2.Values.List = append(ed.L2.Values.List, filedesc.EnumValue{})
+
+	// TODO: Use the presence of a UnmarshalJSON method to determine proto2?
+
+	vd := &ed.L2.Values.List[0]
+	vd.L0.FullName = ed.L0.FullName + "_UNKNOWN" // e.g., github_com.user.repo.MyEnum_UNKNOWN
+	vd.L0.ParentFile = ed.L0.ParentFile
+	vd.L0.Parent = ed
+
+	// TODO: We could use the String method to obtain some enum value names by
+	// starting at 0 and print the enum until it produces invalid identifiers.
+	// An exhaustive query is clearly impractical, but can be best-effort.
+
+	if ed, ok := aberrantEnumDescCache.LoadOrStore(t, ed); ok {
+		return ed.(pref.EnumDescriptor)
+	}
+	return ed
+}
+
+// AberrantDeriveFullName derives a fully qualified protobuf name for the given Go type
+// The provided name is not guaranteed to be stable nor universally unique.
+// It should be sufficiently unique within a program.
+//
+// This is exported for testing purposes.
+func AberrantDeriveFullName(t reflect.Type) pref.FullName {
+	sanitize := func(r rune) rune {
+		switch {
+		case r == '/':
+			return '.'
+		case 'a' <= r && r <= 'z', 'A' <= r && r <= 'Z', '0' <= r && r <= '9':
+			return r
+		default:
+			return '_'
+		}
+	}
+	prefix := strings.Map(sanitize, t.PkgPath())
+	suffix := strings.Map(sanitize, t.Name())
+	if suffix == "" {
+		suffix = fmt.Sprintf("UnknownX%X", reflect.ValueOf(t).Pointer())
+	}
+
+	ss := append(strings.Split(prefix, "."), suffix)
+	for i, s := range ss {
+		if s == "" || ('0' <= s[0] && s[0] <= '9') {
+			ss[i] = "x" + s
+		}
+	}
+	return pref.FullName(strings.Join(ss, "."))
+}

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

@@ -0,0 +1,92 @@
+// Copyright 2019 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package impl
+
+import (
+	"encoding/binary"
+	"encoding/json"
+	"hash/crc32"
+	"math"
+	"reflect"
+
+	"google.golang.org/protobuf/internal/errors"
+	pref "google.golang.org/protobuf/reflect/protoreflect"
+	piface "google.golang.org/protobuf/runtime/protoiface"
+)
+
+// These functions exist to support exported APIs in generated protobufs.
+// While these are deprecated, they cannot be removed for compatibility reasons.
+
+// LegacyEnumName returns the name of enums used in legacy code.
+func (Export) LegacyEnumName(ed pref.EnumDescriptor) string {
+	return legacyEnumName(ed)
+}
+
+// LegacyMessageTypeOf returns the protoreflect.MessageType for m,
+// with name used as the message name if necessary.
+func (Export) LegacyMessageTypeOf(m piface.MessageV1, name pref.FullName) pref.MessageType {
+	if mv := (Export{}).protoMessageV2Of(m); mv != nil {
+		return mv.ProtoReflect().Type()
+	}
+	return legacyLoadMessageInfo(reflect.TypeOf(m), name)
+}
+
+// UnmarshalJSONEnum unmarshals an enum from a JSON-encoded input.
+// The input can either be a string representing the enum value by name,
+// or a number representing the enum number itself.
+func (Export) UnmarshalJSONEnum(ed pref.EnumDescriptor, b []byte) (pref.EnumNumber, error) {
+	if b[0] == '"' {
+		var name pref.Name
+		if err := json.Unmarshal(b, &name); err != nil {
+			return 0, errors.New("invalid input for enum %v: %s", ed.FullName(), b)
+		}
+		ev := ed.Values().ByName(name)
+		if ev == nil {
+			return 0, errors.New("invalid value for enum %v: %s", ed.FullName(), name)
+		}
+		return ev.Number(), nil
+	} else {
+		var num pref.EnumNumber
+		if err := json.Unmarshal(b, &num); err != nil {
+			return 0, errors.New("invalid input for enum %v: %s", ed.FullName(), b)
+		}
+		return num, nil
+	}
+}
+
+// CompressGZIP compresses the input as a GZIP-encoded file.
+// The current implementation does no compression.
+func (Export) CompressGZIP(in []byte) (out []byte) {
+	// RFC 1952, section 2.3.1.
+	var gzipHeader = [10]byte{0x1f, 0x8b, 0x08, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0xff}
+
+	// RFC 1951, section 3.2.4.
+	var blockHeader [5]byte
+	const maxBlockSize = math.MaxUint16
+	numBlocks := 1 + len(in)/maxBlockSize
+
+	// RFC 1952, section 2.3.1.
+	var gzipFooter [8]byte
+	binary.LittleEndian.PutUint32(gzipFooter[0:4], crc32.ChecksumIEEE(in))
+	binary.LittleEndian.PutUint32(gzipFooter[4:8], uint32(len(in)))
+
+	// Encode the input without compression using raw DEFLATE blocks.
+	out = make([]byte, 0, len(gzipHeader)+len(blockHeader)*numBlocks+len(in)+len(gzipFooter))
+	out = append(out, gzipHeader[:]...)
+	for blockHeader[0] == 0 {
+		blockSize := maxBlockSize
+		if blockSize > len(in) {
+			blockHeader[0] = 0x01 // final bit per RFC 1951, section 3.2.3.
+			blockSize = len(in)
+		}
+		binary.LittleEndian.PutUint16(blockHeader[1:3], uint16(blockSize)^0x0000)
+		binary.LittleEndian.PutUint16(blockHeader[3:5], uint16(blockSize)^0xffff)
+		out = append(out, blockHeader[:]...)
+		out = append(out, in[:blockSize]...)
+		in = in[blockSize:]
+	}
+	out = append(out, gzipFooter[:]...)
+	return out
+}

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

@@ -0,0 +1,175 @@
+// Copyright 2018 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package impl
+
+import (
+	"reflect"
+
+	"google.golang.org/protobuf/internal/descopts"
+	"google.golang.org/protobuf/internal/encoding/messageset"
+	ptag "google.golang.org/protobuf/internal/encoding/tag"
+	"google.golang.org/protobuf/internal/filedesc"
+	"google.golang.org/protobuf/internal/pragma"
+	pref "google.golang.org/protobuf/reflect/protoreflect"
+	preg "google.golang.org/protobuf/reflect/protoregistry"
+	piface "google.golang.org/protobuf/runtime/protoiface"
+)
+
+func (xi *ExtensionInfo) initToLegacy() {
+	xd := xi.desc
+	var parent piface.MessageV1
+	messageName := xd.ContainingMessage().FullName()
+	if mt, _ := preg.GlobalTypes.FindMessageByName(messageName); mt != nil {
+		// Create a new parent message and unwrap it if possible.
+		mv := mt.New().Interface()
+		t := reflect.TypeOf(mv)
+		if mv, ok := mv.(unwrapper); ok {
+			t = reflect.TypeOf(mv.protoUnwrap())
+		}
+
+		// Check whether the message implements the legacy v1 Message interface.
+		mz := reflect.Zero(t).Interface()
+		if mz, ok := mz.(piface.MessageV1); ok {
+			parent = mz
+		}
+	}
+
+	// Determine the v1 extension type, which is unfortunately not the same as
+	// the v2 ExtensionType.GoType.
+	extType := xi.goType
+	switch extType.Kind() {
+	case reflect.Bool, reflect.Int32, reflect.Int64, reflect.Uint32, reflect.Uint64, reflect.Float32, reflect.Float64, reflect.String:
+		extType = reflect.PtrTo(extType) // T -> *T for singular scalar fields
+	}
+
+	// Reconstruct the legacy enum full name.
+	var enumName string
+	if xd.Kind() == pref.EnumKind {
+		enumName = legacyEnumName(xd.Enum())
+	}
+
+	// Derive the proto file that the extension was declared within.
+	var filename string
+	if fd := xd.ParentFile(); fd != nil {
+		filename = fd.Path()
+	}
+
+	// For MessageSet extensions, the name used is the parent message.
+	name := xd.FullName()
+	if messageset.IsMessageSetExtension(xd) {
+		name = name.Parent()
+	}
+
+	xi.ExtendedType = parent
+	xi.ExtensionType = reflect.Zero(extType).Interface()
+	xi.Field = int32(xd.Number())
+	xi.Name = string(name)
+	xi.Tag = ptag.Marshal(xd, enumName)
+	xi.Filename = filename
+}
+
+// initFromLegacy initializes an ExtensionInfo from
+// the contents of the deprecated exported fields of the type.
+func (xi *ExtensionInfo) initFromLegacy() {
+	// The v1 API returns "type incomplete" descriptors where only the
+	// field number is specified. In such a case, use a placeholder.
+	if xi.ExtendedType == nil || xi.ExtensionType == nil {
+		xd := placeholderExtension{
+			name:   pref.FullName(xi.Name),
+			number: pref.FieldNumber(xi.Field),
+		}
+		xi.desc = extensionTypeDescriptor{xd, xi}
+		return
+	}
+
+	// Resolve enum or message dependencies.
+	var ed pref.EnumDescriptor
+	var md pref.MessageDescriptor
+	t := reflect.TypeOf(xi.ExtensionType)
+	isOptional := t.Kind() == reflect.Ptr && t.Elem().Kind() != reflect.Struct
+	isRepeated := t.Kind() == reflect.Slice && t.Elem().Kind() != reflect.Uint8
+	if isOptional || isRepeated {
+		t = t.Elem()
+	}
+	switch v := reflect.Zero(t).Interface().(type) {
+	case pref.Enum:
+		ed = v.Descriptor()
+	case enumV1:
+		ed = LegacyLoadEnumDesc(t)
+	case pref.ProtoMessage:
+		md = v.ProtoReflect().Descriptor()
+	case messageV1:
+		md = LegacyLoadMessageDesc(t)
+	}
+
+	// Derive basic field information from the struct tag.
+	var evs pref.EnumValueDescriptors
+	if ed != nil {
+		evs = ed.Values()
+	}
+	fd := ptag.Unmarshal(xi.Tag, t, evs).(*filedesc.Field)
+
+	// Construct a v2 ExtensionType.
+	xd := &filedesc.Extension{L2: new(filedesc.ExtensionL2)}
+	xd.L0.ParentFile = filedesc.SurrogateProto2
+	xd.L0.FullName = pref.FullName(xi.Name)
+	xd.L1.Number = pref.FieldNumber(xi.Field)
+	xd.L1.Cardinality = fd.L1.Cardinality
+	xd.L1.Kind = fd.L1.Kind
+	xd.L2.IsPacked = fd.L1.IsPacked
+	xd.L2.Default = fd.L1.Default
+	xd.L1.Extendee = Export{}.MessageDescriptorOf(xi.ExtendedType)
+	xd.L2.Enum = ed
+	xd.L2.Message = md
+
+	// Derive real extension field name for MessageSets.
+	if messageset.IsMessageSet(xd.L1.Extendee) && md.FullName() == xd.L0.FullName {
+		xd.L0.FullName = xd.L0.FullName.Append(messageset.ExtensionName)
+	}
+
+	tt := reflect.TypeOf(xi.ExtensionType)
+	if isOptional {
+		tt = tt.Elem()
+	}
+	xi.goType = tt
+	xi.desc = extensionTypeDescriptor{xd, xi}
+}
+
+type placeholderExtension struct {
+	name   pref.FullName
+	number pref.FieldNumber
+}
+
+func (x placeholderExtension) ParentFile() pref.FileDescriptor            { return nil }
+func (x placeholderExtension) Parent() pref.Descriptor                    { return nil }
+func (x placeholderExtension) Index() int                                 { return 0 }
+func (x placeholderExtension) Syntax() pref.Syntax                        { return 0 }
+func (x placeholderExtension) Name() pref.Name                            { return x.name.Name() }
+func (x placeholderExtension) FullName() pref.FullName                    { return x.name }
+func (x placeholderExtension) IsPlaceholder() bool                        { return true }
+func (x placeholderExtension) Options() pref.ProtoMessage                 { return descopts.Field }
+func (x placeholderExtension) Number() pref.FieldNumber                   { return x.number }
+func (x placeholderExtension) Cardinality() pref.Cardinality              { return 0 }
+func (x placeholderExtension) Kind() pref.Kind                            { return 0 }
+func (x placeholderExtension) HasJSONName() bool                          { return false }
+func (x placeholderExtension) JSONName() string                           { return "" }
+func (x placeholderExtension) HasPresence() bool                          { return false }
+func (x placeholderExtension) HasOptionalKeyword() bool                   { return false }
+func (x placeholderExtension) IsExtension() bool                          { return true }
+func (x placeholderExtension) IsWeak() bool                               { return false }
+func (x placeholderExtension) IsPacked() bool                             { return false }
+func (x placeholderExtension) IsList() bool                               { return false }
+func (x placeholderExtension) IsMap() bool                                { return false }
+func (x placeholderExtension) MapKey() pref.FieldDescriptor               { return nil }
+func (x placeholderExtension) MapValue() pref.FieldDescriptor             { return nil }
+func (x placeholderExtension) HasDefault() bool                           { return false }
+func (x placeholderExtension) Default() pref.Value                        { return pref.Value{} }
+func (x placeholderExtension) DefaultEnumValue() pref.EnumValueDescriptor { return nil }
+func (x placeholderExtension) ContainingOneof() pref.OneofDescriptor      { return nil }
+func (x placeholderExtension) ContainingMessage() pref.MessageDescriptor  { return nil }
+func (x placeholderExtension) Enum() pref.EnumDescriptor                  { return nil }
+func (x placeholderExtension) Message() pref.MessageDescriptor            { return nil }
+func (x placeholderExtension) ProtoType(pref.FieldDescriptor)             { return }
+func (x placeholderExtension) ProtoInternal(pragma.DoNotImplement)        { return }

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

@@ -0,0 +1,81 @@
+// Copyright 2018 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package impl
+
+import (
+	"bytes"
+	"compress/gzip"
+	"io/ioutil"
+	"sync"
+
+	"google.golang.org/protobuf/internal/filedesc"
+	"google.golang.org/protobuf/reflect/protoreflect"
+	"google.golang.org/protobuf/reflect/protoregistry"
+)
+
+// Every enum and message type generated by protoc-gen-go since commit 2fc053c5
+// on February 25th, 2016 has had a method to get the raw descriptor.
+// Types that were not generated by protoc-gen-go or were generated prior
+// to that version are not supported.
+//
+// The []byte returned is the encoded form of a FileDescriptorProto message
+// compressed using GZIP. The []int is the path from the top-level file
+// to the specific message or enum declaration.
+type (
+	enumV1 interface {
+		EnumDescriptor() ([]byte, []int)
+	}
+	messageV1 interface {
+		Descriptor() ([]byte, []int)
+	}
+)
+
+var legacyFileDescCache sync.Map // map[*byte]protoreflect.FileDescriptor
+
+// legacyLoadFileDesc unmarshals b as a compressed FileDescriptorProto message.
+//
+// This assumes that b is immutable and that b does not refer to part of a
+// concatenated series of GZIP files (which would require shenanigans that
+// rely on the concatenation properties of both protobufs and GZIP).
+// File descriptors generated by protoc-gen-go do not rely on that property.
+func legacyLoadFileDesc(b []byte) protoreflect.FileDescriptor {
+	// Fast-path: check whether we already have a cached file descriptor.
+	if fd, ok := legacyFileDescCache.Load(&b[0]); ok {
+		return fd.(protoreflect.FileDescriptor)
+	}
+
+	// Slow-path: decompress and unmarshal the file descriptor proto.
+	zr, err := gzip.NewReader(bytes.NewReader(b))
+	if err != nil {
+		panic(err)
+	}
+	b2, err := ioutil.ReadAll(zr)
+	if err != nil {
+		panic(err)
+	}
+
+	fd := filedesc.Builder{
+		RawDescriptor: b2,
+		FileRegistry:  resolverOnly{protoregistry.GlobalFiles}, // do not register back to global registry
+	}.Build().File
+	if fd, ok := legacyFileDescCache.LoadOrStore(&b[0], fd); ok {
+		return fd.(protoreflect.FileDescriptor)
+	}
+	return fd
+}
+
+type resolverOnly struct {
+	reg *protoregistry.Files
+}
+
+func (r resolverOnly) FindFileByPath(path string) (protoreflect.FileDescriptor, error) {
+	return r.reg.FindFileByPath(path)
+}
+func (r resolverOnly) FindDescriptorByName(name protoreflect.FullName) (protoreflect.Descriptor, error) {
+	return r.reg.FindDescriptorByName(name)
+}
+func (resolverOnly) RegisterFile(protoreflect.FileDescriptor) error {
+	return nil
+}

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

@@ -0,0 +1,502 @@
+// Copyright 2018 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package impl
+
+import (
+	"fmt"
+	"reflect"
+	"strings"
+	"sync"
+
+	"google.golang.org/protobuf/internal/descopts"
+	ptag "google.golang.org/protobuf/internal/encoding/tag"
+	"google.golang.org/protobuf/internal/errors"
+	"google.golang.org/protobuf/internal/filedesc"
+	"google.golang.org/protobuf/internal/strs"
+	"google.golang.org/protobuf/reflect/protoreflect"
+	pref "google.golang.org/protobuf/reflect/protoreflect"
+	"google.golang.org/protobuf/runtime/protoiface"
+	piface "google.golang.org/protobuf/runtime/protoiface"
+)
+
+// legacyWrapMessage wraps v as a protoreflect.Message,
+// where v must be a *struct kind and not implement the v2 API already.
+func legacyWrapMessage(v reflect.Value) pref.Message {
+	typ := v.Type()
+	if typ.Kind() != reflect.Ptr || typ.Elem().Kind() != reflect.Struct {
+		return aberrantMessage{v: v}
+	}
+	mt := legacyLoadMessageInfo(typ, "")
+	return mt.MessageOf(v.Interface())
+}
+
+var legacyMessageTypeCache sync.Map // map[reflect.Type]*MessageInfo
+
+// legacyLoadMessageInfo dynamically loads a *MessageInfo for t,
+// where t must be a *struct kind and not implement the v2 API already.
+// The provided name is used if it cannot be determined from the message.
+func legacyLoadMessageInfo(t reflect.Type, name pref.FullName) *MessageInfo {
+	// Fast-path: check if a MessageInfo is cached for this concrete type.
+	if mt, ok := legacyMessageTypeCache.Load(t); ok {
+		return mt.(*MessageInfo)
+	}
+
+	// Slow-path: derive message descriptor and initialize MessageInfo.
+	mi := &MessageInfo{
+		Desc:          legacyLoadMessageDesc(t, name),
+		GoReflectType: t,
+	}
+
+	v := reflect.Zero(t).Interface()
+	if _, ok := v.(legacyMarshaler); ok {
+		mi.methods.Marshal = legacyMarshal
+
+		// We have no way to tell whether the type's Marshal method
+		// supports deterministic serialization or not, but this
+		// preserves the v1 implementation's behavior of always
+		// calling Marshal methods when present.
+		mi.methods.Flags |= piface.SupportMarshalDeterministic
+	}
+	if _, ok := v.(legacyUnmarshaler); ok {
+		mi.methods.Unmarshal = legacyUnmarshal
+	}
+	if _, ok := v.(legacyMerger); ok {
+		mi.methods.Merge = legacyMerge
+	}
+
+	if mi, ok := legacyMessageTypeCache.LoadOrStore(t, mi); ok {
+		return mi.(*MessageInfo)
+	}
+	return mi
+}
+
+var legacyMessageDescCache sync.Map // map[reflect.Type]protoreflect.MessageDescriptor
+
+// LegacyLoadMessageDesc returns an MessageDescriptor derived from the Go type,
+// which must be a *struct kind and not implement the v2 API already.
+//
+// This is exported for testing purposes.
+func LegacyLoadMessageDesc(t reflect.Type) pref.MessageDescriptor {
+	return legacyLoadMessageDesc(t, "")
+}
+func legacyLoadMessageDesc(t reflect.Type, name pref.FullName) pref.MessageDescriptor {
+	// Fast-path: check if a MessageDescriptor is cached for this concrete type.
+	if mi, ok := legacyMessageDescCache.Load(t); ok {
+		return mi.(pref.MessageDescriptor)
+	}
+
+	// Slow-path: initialize MessageDescriptor from the raw descriptor.
+	mv := reflect.Zero(t).Interface()
+	if _, ok := mv.(pref.ProtoMessage); ok {
+		panic(fmt.Sprintf("%v already implements proto.Message", t))
+	}
+	mdV1, ok := mv.(messageV1)
+	if !ok {
+		return aberrantLoadMessageDesc(t, name)
+	}
+
+	// If this is a dynamic message type where there isn't a 1-1 mapping between
+	// Go and protobuf types, calling the Descriptor method on the zero value of
+	// the message type isn't likely to work. If it panics, swallow the panic and
+	// continue as if the Descriptor method wasn't present.
+	b, idxs := func() ([]byte, []int) {
+		defer func() {
+			recover()
+		}()
+		return mdV1.Descriptor()
+	}()
+	if b == nil {
+		return aberrantLoadMessageDesc(t, name)
+	}
+
+	// If the Go type has no fields, then this might be a proto3 empty message
+	// from before the size cache was added. If there are any fields, check to
+	// see that at least one of them looks like something we generated.
+	if nfield := t.Elem().NumField(); nfield > 0 {
+		hasProtoField := false
+		for i := 0; i < nfield; i++ {
+			f := t.Elem().Field(i)
+			if f.Tag.Get("protobuf") != "" || f.Tag.Get("protobuf_oneof") != "" || strings.HasPrefix(f.Name, "XXX_") {
+				hasProtoField = true
+				break
+			}
+		}
+		if !hasProtoField {
+			return aberrantLoadMessageDesc(t, name)
+		}
+	}
+
+	md := legacyLoadFileDesc(b).Messages().Get(idxs[0])
+	for _, i := range idxs[1:] {
+		md = md.Messages().Get(i)
+	}
+	if name != "" && md.FullName() != name {
+		panic(fmt.Sprintf("mismatching message name: got %v, want %v", md.FullName(), name))
+	}
+	if md, ok := legacyMessageDescCache.LoadOrStore(t, md); ok {
+		return md.(protoreflect.MessageDescriptor)
+	}
+	return md
+}
+
+var (
+	aberrantMessageDescLock  sync.Mutex
+	aberrantMessageDescCache map[reflect.Type]protoreflect.MessageDescriptor
+)
+
+// aberrantLoadMessageDesc returns an MessageDescriptor derived from the Go type,
+// which must not implement protoreflect.ProtoMessage or messageV1.
+//
+// This is a best-effort derivation of the message descriptor using the protobuf
+// tags on the struct fields.
+func aberrantLoadMessageDesc(t reflect.Type, name pref.FullName) pref.MessageDescriptor {
+	aberrantMessageDescLock.Lock()
+	defer aberrantMessageDescLock.Unlock()
+	if aberrantMessageDescCache == nil {
+		aberrantMessageDescCache = make(map[reflect.Type]protoreflect.MessageDescriptor)
+	}
+	return aberrantLoadMessageDescReentrant(t, name)
+}
+func aberrantLoadMessageDescReentrant(t reflect.Type, name pref.FullName) pref.MessageDescriptor {
+	// Fast-path: check if an MessageDescriptor is cached for this concrete type.
+	if md, ok := aberrantMessageDescCache[t]; ok {
+		return md
+	}
+
+	// Slow-path: construct a descriptor from the Go struct type (best-effort).
+	// Cache the MessageDescriptor early on so that we can resolve internal
+	// cyclic references.
+	md := &filedesc.Message{L2: new(filedesc.MessageL2)}
+	md.L0.FullName = aberrantDeriveMessageName(t, name)
+	md.L0.ParentFile = filedesc.SurrogateProto2
+	aberrantMessageDescCache[t] = md
+
+	if t.Kind() != reflect.Ptr || t.Elem().Kind() != reflect.Struct {
+		return md
+	}
+
+	// Try to determine if the message is using proto3 by checking scalars.
+	for i := 0; i < t.Elem().NumField(); i++ {
+		f := t.Elem().Field(i)
+		if tag := f.Tag.Get("protobuf"); tag != "" {
+			switch f.Type.Kind() {
+			case reflect.Bool, reflect.Int32, reflect.Int64, reflect.Uint32, reflect.Uint64, reflect.Float32, reflect.Float64, reflect.String:
+				md.L0.ParentFile = filedesc.SurrogateProto3
+			}
+			for _, s := range strings.Split(tag, ",") {
+				if s == "proto3" {
+					md.L0.ParentFile = filedesc.SurrogateProto3
+				}
+			}
+		}
+	}
+
+	// Obtain a list of oneof wrapper types.
+	var oneofWrappers []reflect.Type
+	for _, method := range []string{"XXX_OneofFuncs", "XXX_OneofWrappers"} {
+		if fn, ok := t.MethodByName(method); ok {
+			for _, v := range fn.Func.Call([]reflect.Value{reflect.Zero(fn.Type.In(0))}) {
+				if vs, ok := v.Interface().([]interface{}); ok {
+					for _, v := range vs {
+						oneofWrappers = append(oneofWrappers, reflect.TypeOf(v))
+					}
+				}
+			}
+		}
+	}
+
+	// Obtain a list of the extension ranges.
+	if fn, ok := t.MethodByName("ExtensionRangeArray"); ok {
+		vs := fn.Func.Call([]reflect.Value{reflect.Zero(fn.Type.In(0))})[0]
+		for i := 0; i < vs.Len(); i++ {
+			v := vs.Index(i)
+			md.L2.ExtensionRanges.List = append(md.L2.ExtensionRanges.List, [2]pref.FieldNumber{
+				pref.FieldNumber(v.FieldByName("Start").Int()),
+				pref.FieldNumber(v.FieldByName("End").Int() + 1),
+			})
+			md.L2.ExtensionRangeOptions = append(md.L2.ExtensionRangeOptions, nil)
+		}
+	}
+
+	// Derive the message fields by inspecting the struct fields.
+	for i := 0; i < t.Elem().NumField(); i++ {
+		f := t.Elem().Field(i)
+		if tag := f.Tag.Get("protobuf"); tag != "" {
+			tagKey := f.Tag.Get("protobuf_key")
+			tagVal := f.Tag.Get("protobuf_val")
+			aberrantAppendField(md, f.Type, tag, tagKey, tagVal)
+		}
+		if tag := f.Tag.Get("protobuf_oneof"); tag != "" {
+			n := len(md.L2.Oneofs.List)
+			md.L2.Oneofs.List = append(md.L2.Oneofs.List, filedesc.Oneof{})
+			od := &md.L2.Oneofs.List[n]
+			od.L0.FullName = md.FullName().Append(pref.Name(tag))
+			od.L0.ParentFile = md.L0.ParentFile
+			od.L0.Parent = md
+			od.L0.Index = n
+
+			for _, t := range oneofWrappers {
+				if t.Implements(f.Type) {
+					f := t.Elem().Field(0)
+					if tag := f.Tag.Get("protobuf"); tag != "" {
+						aberrantAppendField(md, f.Type, tag, "", "")
+						fd := &md.L2.Fields.List[len(md.L2.Fields.List)-1]
+						fd.L1.ContainingOneof = od
+						od.L1.Fields.List = append(od.L1.Fields.List, fd)
+					}
+				}
+			}
+		}
+	}
+
+	return md
+}
+
+func aberrantDeriveMessageName(t reflect.Type, name pref.FullName) pref.FullName {
+	if name.IsValid() {
+		return name
+	}
+	func() {
+		defer func() { recover() }() // swallow possible nil panics
+		if m, ok := reflect.Zero(t).Interface().(interface{ XXX_MessageName() string }); ok {
+			name = pref.FullName(m.XXX_MessageName())
+		}
+	}()
+	if name.IsValid() {
+		return name
+	}
+	if t.Kind() == reflect.Ptr {
+		t = t.Elem()
+	}
+	return AberrantDeriveFullName(t)
+}
+
+func aberrantAppendField(md *filedesc.Message, goType reflect.Type, tag, tagKey, tagVal string) {
+	t := goType
+	isOptional := t.Kind() == reflect.Ptr && t.Elem().Kind() != reflect.Struct
+	isRepeated := t.Kind() == reflect.Slice && t.Elem().Kind() != reflect.Uint8
+	if isOptional || isRepeated {
+		t = t.Elem()
+	}
+	fd := ptag.Unmarshal(tag, t, placeholderEnumValues{}).(*filedesc.Field)
+
+	// Append field descriptor to the message.
+	n := len(md.L2.Fields.List)
+	md.L2.Fields.List = append(md.L2.Fields.List, *fd)
+	fd = &md.L2.Fields.List[n]
+	fd.L0.FullName = md.FullName().Append(fd.Name())
+	fd.L0.ParentFile = md.L0.ParentFile
+	fd.L0.Parent = md
+	fd.L0.Index = n
+
+	if fd.L1.IsWeak || fd.L1.HasPacked {
+		fd.L1.Options = func() pref.ProtoMessage {
+			opts := descopts.Field.ProtoReflect().New()
+			if fd.L1.IsWeak {
+				opts.Set(opts.Descriptor().Fields().ByName("weak"), protoreflect.ValueOfBool(true))
+			}
+			if fd.L1.HasPacked {
+				opts.Set(opts.Descriptor().Fields().ByName("packed"), protoreflect.ValueOfBool(fd.L1.IsPacked))
+			}
+			return opts.Interface()
+		}
+	}
+
+	// Populate Enum and Message.
+	if fd.Enum() == nil && fd.Kind() == pref.EnumKind {
+		switch v := reflect.Zero(t).Interface().(type) {
+		case pref.Enum:
+			fd.L1.Enum = v.Descriptor()
+		default:
+			fd.L1.Enum = LegacyLoadEnumDesc(t)
+		}
+	}
+	if fd.Message() == nil && (fd.Kind() == pref.MessageKind || fd.Kind() == pref.GroupKind) {
+		switch v := reflect.Zero(t).Interface().(type) {
+		case pref.ProtoMessage:
+			fd.L1.Message = v.ProtoReflect().Descriptor()
+		case messageV1:
+			fd.L1.Message = LegacyLoadMessageDesc(t)
+		default:
+			if t.Kind() == reflect.Map {
+				n := len(md.L1.Messages.List)
+				md.L1.Messages.List = append(md.L1.Messages.List, filedesc.Message{L2: new(filedesc.MessageL2)})
+				md2 := &md.L1.Messages.List[n]
+				md2.L0.FullName = md.FullName().Append(pref.Name(strs.MapEntryName(string(fd.Name()))))
+				md2.L0.ParentFile = md.L0.ParentFile
+				md2.L0.Parent = md
+				md2.L0.Index = n
+
+				md2.L1.IsMapEntry = true
+				md2.L2.Options = func() pref.ProtoMessage {
+					opts := descopts.Message.ProtoReflect().New()
+					opts.Set(opts.Descriptor().Fields().ByName("map_entry"), protoreflect.ValueOfBool(true))
+					return opts.Interface()
+				}
+
+				aberrantAppendField(md2, t.Key(), tagKey, "", "")
+				aberrantAppendField(md2, t.Elem(), tagVal, "", "")
+
+				fd.L1.Message = md2
+				break
+			}
+			fd.L1.Message = aberrantLoadMessageDescReentrant(t, "")
+		}
+	}
+}
+
+type placeholderEnumValues struct {
+	protoreflect.EnumValueDescriptors
+}
+
+func (placeholderEnumValues) ByNumber(n pref.EnumNumber) pref.EnumValueDescriptor {
+	return filedesc.PlaceholderEnumValue(pref.FullName(fmt.Sprintf("UNKNOWN_%d", n)))
+}
+
+// legacyMarshaler is the proto.Marshaler interface superseded by protoiface.Methoder.
+type legacyMarshaler interface {
+	Marshal() ([]byte, error)
+}
+
+// legacyUnmarshaler is the proto.Unmarshaler interface superseded by protoiface.Methoder.
+type legacyUnmarshaler interface {
+	Unmarshal([]byte) error
+}
+
+// legacyMerger is the proto.Merger interface superseded by protoiface.Methoder.
+type legacyMerger interface {
+	Merge(protoiface.MessageV1)
+}
+
+var legacyProtoMethods = &piface.Methods{
+	Marshal:   legacyMarshal,
+	Unmarshal: legacyUnmarshal,
+	Merge:     legacyMerge,
+
+	// We have no way to tell whether the type's Marshal method
+	// supports deterministic serialization or not, but this
+	// preserves the v1 implementation's behavior of always
+	// calling Marshal methods when present.
+	Flags: piface.SupportMarshalDeterministic,
+}
+
+func legacyMarshal(in piface.MarshalInput) (piface.MarshalOutput, error) {
+	v := in.Message.(unwrapper).protoUnwrap()
+	marshaler, ok := v.(legacyMarshaler)
+	if !ok {
+		return piface.MarshalOutput{}, errors.New("%T does not implement Marshal", v)
+	}
+	out, err := marshaler.Marshal()
+	if in.Buf != nil {
+		out = append(in.Buf, out...)
+	}
+	return piface.MarshalOutput{
+		Buf: out,
+	}, err
+}
+
+func legacyUnmarshal(in piface.UnmarshalInput) (piface.UnmarshalOutput, error) {
+	v := in.Message.(unwrapper).protoUnwrap()
+	unmarshaler, ok := v.(legacyUnmarshaler)
+	if !ok {
+		return piface.UnmarshalOutput{}, errors.New("%T does not implement Marshal", v)
+	}
+	return piface.UnmarshalOutput{}, unmarshaler.Unmarshal(in.Buf)
+}
+
+func legacyMerge(in piface.MergeInput) piface.MergeOutput {
+	dstv := in.Destination.(unwrapper).protoUnwrap()
+	merger, ok := dstv.(legacyMerger)
+	if !ok {
+		return piface.MergeOutput{}
+	}
+	merger.Merge(Export{}.ProtoMessageV1Of(in.Source))
+	return piface.MergeOutput{Flags: piface.MergeComplete}
+}
+
+// aberrantMessageType implements MessageType for all types other than pointer-to-struct.
+type aberrantMessageType struct {
+	t reflect.Type
+}
+
+func (mt aberrantMessageType) New() pref.Message {
+	return aberrantMessage{reflect.Zero(mt.t)}
+}
+func (mt aberrantMessageType) Zero() pref.Message {
+	return aberrantMessage{reflect.Zero(mt.t)}
+}
+func (mt aberrantMessageType) GoType() reflect.Type {
+	return mt.t
+}
+func (mt aberrantMessageType) Descriptor() pref.MessageDescriptor {
+	return LegacyLoadMessageDesc(mt.t)
+}
+
+// aberrantMessage implements Message for all types other than pointer-to-struct.
+//
+// When the underlying type implements legacyMarshaler or legacyUnmarshaler,
+// the aberrant Message can be marshaled or unmarshaled. Otherwise, there is
+// not much that can be done with values of this type.
+type aberrantMessage struct {
+	v reflect.Value
+}
+
+func (m aberrantMessage) ProtoReflect() pref.Message {
+	return m
+}
+
+func (m aberrantMessage) Descriptor() pref.MessageDescriptor {
+	return LegacyLoadMessageDesc(m.v.Type())
+}
+func (m aberrantMessage) Type() pref.MessageType {
+	return aberrantMessageType{m.v.Type()}
+}
+func (m aberrantMessage) New() pref.Message {
+	return aberrantMessage{reflect.Zero(m.v.Type())}
+}
+func (m aberrantMessage) Interface() pref.ProtoMessage {
+	return m
+}
+func (m aberrantMessage) Range(f func(pref.FieldDescriptor, pref.Value) bool) {
+}
+func (m aberrantMessage) Has(pref.FieldDescriptor) bool {
+	panic("invalid field descriptor")
+}
+func (m aberrantMessage) Clear(pref.FieldDescriptor) {
+	panic("invalid field descriptor")
+}
+func (m aberrantMessage) Get(pref.FieldDescriptor) pref.Value {
+	panic("invalid field descriptor")
+}
+func (m aberrantMessage) Set(pref.FieldDescriptor, pref.Value) {
+	panic("invalid field descriptor")
+}
+func (m aberrantMessage) Mutable(pref.FieldDescriptor) pref.Value {
+	panic("invalid field descriptor")
+}
+func (m aberrantMessage) NewField(pref.FieldDescriptor) pref.Value {
+	panic("invalid field descriptor")
+}
+func (m aberrantMessage) WhichOneof(pref.OneofDescriptor) pref.FieldDescriptor {
+	panic("invalid oneof descriptor")
+}
+func (m aberrantMessage) GetUnknown() pref.RawFields {
+	return nil
+}
+func (m aberrantMessage) SetUnknown(pref.RawFields) {
+	// SetUnknown discards its input on messages which don't support unknown field storage.
+}
+func (m aberrantMessage) IsValid() bool {
+	// An invalid message is a read-only, empty message. Since we don't know anything
+	// about the alleged contents of this message, we can't say with confidence that
+	// it is invalid in this sense. Therefore, report it as valid.
+	return true
+}
+func (m aberrantMessage) ProtoMethods() *piface.Methods {
+	return legacyProtoMethods
+}
+func (m aberrantMessage) protoUnwrap() interface{} {
+	return m.v.Interface()
+}

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

@@ -0,0 +1,176 @@
+// Copyright 2020 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package impl
+
+import (
+	"fmt"
+	"reflect"
+
+	"google.golang.org/protobuf/proto"
+	pref "google.golang.org/protobuf/reflect/protoreflect"
+	piface "google.golang.org/protobuf/runtime/protoiface"
+)
+
+type mergeOptions struct{}
+
+func (o mergeOptions) Merge(dst, src proto.Message) {
+	proto.Merge(dst, src)
+}
+
+// merge is protoreflect.Methods.Merge.
+func (mi *MessageInfo) merge(in piface.MergeInput) piface.MergeOutput {
+	dp, ok := mi.getPointer(in.Destination)
+	if !ok {
+		return piface.MergeOutput{}
+	}
+	sp, ok := mi.getPointer(in.Source)
+	if !ok {
+		return piface.MergeOutput{}
+	}
+	mi.mergePointer(dp, sp, mergeOptions{})
+	return piface.MergeOutput{Flags: piface.MergeComplete}
+}
+
+func (mi *MessageInfo) mergePointer(dst, src pointer, opts mergeOptions) {
+	mi.init()
+	if dst.IsNil() {
+		panic(fmt.Sprintf("invalid value: merging into nil message"))
+	}
+	if src.IsNil() {
+		return
+	}
+	for _, f := range mi.orderedCoderFields {
+		if f.funcs.merge == nil {
+			continue
+		}
+		sfptr := src.Apply(f.offset)
+		if f.isPointer && sfptr.Elem().IsNil() {
+			continue
+		}
+		f.funcs.merge(dst.Apply(f.offset), sfptr, f, opts)
+	}
+	if mi.extensionOffset.IsValid() {
+		sext := src.Apply(mi.extensionOffset).Extensions()
+		dext := dst.Apply(mi.extensionOffset).Extensions()
+		if *dext == nil {
+			*dext = make(map[int32]ExtensionField)
+		}
+		for num, sx := range *sext {
+			xt := sx.Type()
+			xi := getExtensionFieldInfo(xt)
+			if xi.funcs.merge == nil {
+				continue
+			}
+			dx := (*dext)[num]
+			var dv pref.Value
+			if dx.Type() == sx.Type() {
+				dv = dx.Value()
+			}
+			if !dv.IsValid() && xi.unmarshalNeedsValue {
+				dv = xt.New()
+			}
+			dv = xi.funcs.merge(dv, sx.Value(), opts)
+			dx.Set(sx.Type(), dv)
+			(*dext)[num] = dx
+		}
+	}
+	if mi.unknownOffset.IsValid() {
+		du := dst.Apply(mi.unknownOffset).Bytes()
+		su := src.Apply(mi.unknownOffset).Bytes()
+		if len(*su) > 0 {
+			*du = append(*du, *su...)
+		}
+	}
+}
+
+func mergeScalarValue(dst, src pref.Value, opts mergeOptions) pref.Value {
+	return src
+}
+
+func mergeBytesValue(dst, src pref.Value, opts mergeOptions) pref.Value {
+	return pref.ValueOfBytes(append(emptyBuf[:], src.Bytes()...))
+}
+
+func mergeListValue(dst, src pref.Value, opts mergeOptions) pref.Value {
+	dstl := dst.List()
+	srcl := src.List()
+	for i, llen := 0, srcl.Len(); i < llen; i++ {
+		dstl.Append(srcl.Get(i))
+	}
+	return dst
+}
+
+func mergeBytesListValue(dst, src pref.Value, opts mergeOptions) pref.Value {
+	dstl := dst.List()
+	srcl := src.List()
+	for i, llen := 0, srcl.Len(); i < llen; i++ {
+		sb := srcl.Get(i).Bytes()
+		db := append(emptyBuf[:], sb...)
+		dstl.Append(pref.ValueOfBytes(db))
+	}
+	return dst
+}
+
+func mergeMessageListValue(dst, src pref.Value, opts mergeOptions) pref.Value {
+	dstl := dst.List()
+	srcl := src.List()
+	for i, llen := 0, srcl.Len(); i < llen; i++ {
+		sm := srcl.Get(i).Message()
+		dm := proto.Clone(sm.Interface()).ProtoReflect()
+		dstl.Append(pref.ValueOfMessage(dm))
+	}
+	return dst
+}
+
+func mergeMessageValue(dst, src pref.Value, opts mergeOptions) pref.Value {
+	opts.Merge(dst.Message().Interface(), src.Message().Interface())
+	return dst
+}
+
+func mergeMessage(dst, src pointer, f *coderFieldInfo, opts mergeOptions) {
+	if f.mi != nil {
+		if dst.Elem().IsNil() {
+			dst.SetPointer(pointerOfValue(reflect.New(f.mi.GoReflectType.Elem())))
+		}
+		f.mi.mergePointer(dst.Elem(), src.Elem(), opts)
+	} else {
+		dm := dst.AsValueOf(f.ft).Elem()
+		sm := src.AsValueOf(f.ft).Elem()
+		if dm.IsNil() {
+			dm.Set(reflect.New(f.ft.Elem()))
+		}
+		opts.Merge(asMessage(dm), asMessage(sm))
+	}
+}
+
+func mergeMessageSlice(dst, src pointer, f *coderFieldInfo, opts mergeOptions) {
+	for _, sp := range src.PointerSlice() {
+		dm := reflect.New(f.ft.Elem().Elem())
+		if f.mi != nil {
+			f.mi.mergePointer(pointerOfValue(dm), sp, opts)
+		} else {
+			opts.Merge(asMessage(dm), asMessage(sp.AsValueOf(f.ft.Elem().Elem())))
+		}
+		dst.AppendPointerSlice(pointerOfValue(dm))
+	}
+}
+
+func mergeBytes(dst, src pointer, _ *coderFieldInfo, _ mergeOptions) {
+	*dst.Bytes() = append(emptyBuf[:], *src.Bytes()...)
+}
+
+func mergeBytesNoZero(dst, src pointer, _ *coderFieldInfo, _ mergeOptions) {
+	v := *src.Bytes()
+	if len(v) > 0 {
+		*dst.Bytes() = append(emptyBuf[:], v...)
+	}
+}
+
+func mergeBytesSlice(dst, src pointer, _ *coderFieldInfo, _ mergeOptions) {
+	ds := dst.BytesSlice()
+	for _, v := range *src.BytesSlice() {
+		*ds = append(*ds, append(emptyBuf[:], v...))
+	}
+}

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

@@ -0,0 +1,209 @@
+// Copyright 2018 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Code generated by generate-types. DO NOT EDIT.
+
+package impl
+
+import ()
+
+func mergeBool(dst, src pointer, _ *coderFieldInfo, _ mergeOptions) {
+	*dst.Bool() = *src.Bool()
+}
+
+func mergeBoolNoZero(dst, src pointer, _ *coderFieldInfo, _ mergeOptions) {
+	v := *src.Bool()
+	if v != false {
+		*dst.Bool() = v
+	}
+}
+
+func mergeBoolPtr(dst, src pointer, _ *coderFieldInfo, _ mergeOptions) {
+	p := *src.BoolPtr()
+	if p != nil {
+		v := *p
+		*dst.BoolPtr() = &v
+	}
+}
+
+func mergeBoolSlice(dst, src pointer, _ *coderFieldInfo, _ mergeOptions) {
+	ds := dst.BoolSlice()
+	ss := src.BoolSlice()
+	*ds = append(*ds, *ss...)
+}
+
+func mergeInt32(dst, src pointer, _ *coderFieldInfo, _ mergeOptions) {
+	*dst.Int32() = *src.Int32()
+}
+
+func mergeInt32NoZero(dst, src pointer, _ *coderFieldInfo, _ mergeOptions) {
+	v := *src.Int32()
+	if v != 0 {
+		*dst.Int32() = v
+	}
+}
+
+func mergeInt32Ptr(dst, src pointer, _ *coderFieldInfo, _ mergeOptions) {
+	p := *src.Int32Ptr()
+	if p != nil {
+		v := *p
+		*dst.Int32Ptr() = &v
+	}
+}
+
+func mergeInt32Slice(dst, src pointer, _ *coderFieldInfo, _ mergeOptions) {
+	ds := dst.Int32Slice()
+	ss := src.Int32Slice()
+	*ds = append(*ds, *ss...)
+}
+
+func mergeUint32(dst, src pointer, _ *coderFieldInfo, _ mergeOptions) {
+	*dst.Uint32() = *src.Uint32()
+}
+
+func mergeUint32NoZero(dst, src pointer, _ *coderFieldInfo, _ mergeOptions) {
+	v := *src.Uint32()
+	if v != 0 {
+		*dst.Uint32() = v
+	}
+}
+
+func mergeUint32Ptr(dst, src pointer, _ *coderFieldInfo, _ mergeOptions) {
+	p := *src.Uint32Ptr()
+	if p != nil {
+		v := *p
+		*dst.Uint32Ptr() = &v
+	}
+}
+
+func mergeUint32Slice(dst, src pointer, _ *coderFieldInfo, _ mergeOptions) {
+	ds := dst.Uint32Slice()
+	ss := src.Uint32Slice()
+	*ds = append(*ds, *ss...)
+}
+
+func mergeInt64(dst, src pointer, _ *coderFieldInfo, _ mergeOptions) {
+	*dst.Int64() = *src.Int64()
+}
+
+func mergeInt64NoZero(dst, src pointer, _ *coderFieldInfo, _ mergeOptions) {
+	v := *src.Int64()
+	if v != 0 {
+		*dst.Int64() = v
+	}
+}
+
+func mergeInt64Ptr(dst, src pointer, _ *coderFieldInfo, _ mergeOptions) {
+	p := *src.Int64Ptr()
+	if p != nil {
+		v := *p
+		*dst.Int64Ptr() = &v
+	}
+}
+
+func mergeInt64Slice(dst, src pointer, _ *coderFieldInfo, _ mergeOptions) {
+	ds := dst.Int64Slice()
+	ss := src.Int64Slice()
+	*ds = append(*ds, *ss...)
+}
+
+func mergeUint64(dst, src pointer, _ *coderFieldInfo, _ mergeOptions) {
+	*dst.Uint64() = *src.Uint64()
+}
+
+func mergeUint64NoZero(dst, src pointer, _ *coderFieldInfo, _ mergeOptions) {
+	v := *src.Uint64()
+	if v != 0 {
+		*dst.Uint64() = v
+	}
+}
+
+func mergeUint64Ptr(dst, src pointer, _ *coderFieldInfo, _ mergeOptions) {
+	p := *src.Uint64Ptr()
+	if p != nil {
+		v := *p
+		*dst.Uint64Ptr() = &v
+	}
+}
+
+func mergeUint64Slice(dst, src pointer, _ *coderFieldInfo, _ mergeOptions) {
+	ds := dst.Uint64Slice()
+	ss := src.Uint64Slice()
+	*ds = append(*ds, *ss...)
+}
+
+func mergeFloat32(dst, src pointer, _ *coderFieldInfo, _ mergeOptions) {
+	*dst.Float32() = *src.Float32()
+}
+
+func mergeFloat32NoZero(dst, src pointer, _ *coderFieldInfo, _ mergeOptions) {
+	v := *src.Float32()
+	if v != 0 {
+		*dst.Float32() = v
+	}
+}
+
+func mergeFloat32Ptr(dst, src pointer, _ *coderFieldInfo, _ mergeOptions) {
+	p := *src.Float32Ptr()
+	if p != nil {
+		v := *p
+		*dst.Float32Ptr() = &v
+	}
+}
+
+func mergeFloat32Slice(dst, src pointer, _ *coderFieldInfo, _ mergeOptions) {
+	ds := dst.Float32Slice()
+	ss := src.Float32Slice()
+	*ds = append(*ds, *ss...)
+}
+
+func mergeFloat64(dst, src pointer, _ *coderFieldInfo, _ mergeOptions) {
+	*dst.Float64() = *src.Float64()
+}
+
+func mergeFloat64NoZero(dst, src pointer, _ *coderFieldInfo, _ mergeOptions) {
+	v := *src.Float64()
+	if v != 0 {
+		*dst.Float64() = v
+	}
+}
+
+func mergeFloat64Ptr(dst, src pointer, _ *coderFieldInfo, _ mergeOptions) {
+	p := *src.Float64Ptr()
+	if p != nil {
+		v := *p
+		*dst.Float64Ptr() = &v
+	}
+}
+
+func mergeFloat64Slice(dst, src pointer, _ *coderFieldInfo, _ mergeOptions) {
+	ds := dst.Float64Slice()
+	ss := src.Float64Slice()
+	*ds = append(*ds, *ss...)
+}
+
+func mergeString(dst, src pointer, _ *coderFieldInfo, _ mergeOptions) {
+	*dst.String() = *src.String()
+}
+
+func mergeStringNoZero(dst, src pointer, _ *coderFieldInfo, _ mergeOptions) {
+	v := *src.String()
+	if v != "" {
+		*dst.String() = v
+	}
+}
+
+func mergeStringPtr(dst, src pointer, _ *coderFieldInfo, _ mergeOptions) {
+	p := *src.StringPtr()
+	if p != nil {
+		v := *p
+		*dst.StringPtr() = &v
+	}
+}
+
+func mergeStringSlice(dst, src pointer, _ *coderFieldInfo, _ mergeOptions) {
+	ds := dst.StringSlice()
+	ss := src.StringSlice()
+	*ds = append(*ds, *ss...)
+}

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

@@ -0,0 +1,215 @@
+// Copyright 2018 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package impl
+
+import (
+	"fmt"
+	"reflect"
+	"strconv"
+	"strings"
+	"sync"
+	"sync/atomic"
+
+	"google.golang.org/protobuf/internal/genid"
+	"google.golang.org/protobuf/reflect/protoreflect"
+	pref "google.golang.org/protobuf/reflect/protoreflect"
+)
+
+// MessageInfo provides protobuf related functionality for a given Go type
+// that represents a message. A given instance of MessageInfo is tied to
+// exactly one Go type, which must be a pointer to a struct type.
+//
+// The exported fields must be populated before any methods are called
+// and cannot be mutated after set.
+type MessageInfo struct {
+	// GoReflectType is the underlying message Go type and must be populated.
+	GoReflectType reflect.Type // pointer to struct
+
+	// Desc is the underlying message descriptor type and must be populated.
+	Desc pref.MessageDescriptor
+
+	// Exporter must be provided in a purego environment in order to provide
+	// access to unexported fields.
+	Exporter exporter
+
+	// OneofWrappers is list of pointers to oneof wrapper struct types.
+	OneofWrappers []interface{}
+
+	initMu   sync.Mutex // protects all unexported fields
+	initDone uint32
+
+	reflectMessageInfo // for reflection implementation
+	coderMessageInfo   // for fast-path method implementations
+}
+
+// exporter is a function that returns a reference to the ith field of v,
+// where v is a pointer to a struct. It returns nil if it does not support
+// exporting the requested field (e.g., already exported).
+type exporter func(v interface{}, i int) interface{}
+
+// getMessageInfo returns the MessageInfo for any message type that
+// is generated by our implementation of protoc-gen-go (for v2 and on).
+// If it is unable to obtain a MessageInfo, it returns nil.
+func getMessageInfo(mt reflect.Type) *MessageInfo {
+	m, ok := reflect.Zero(mt).Interface().(pref.ProtoMessage)
+	if !ok {
+		return nil
+	}
+	mr, ok := m.ProtoReflect().(interface{ ProtoMessageInfo() *MessageInfo })
+	if !ok {
+		return nil
+	}
+	return mr.ProtoMessageInfo()
+}
+
+func (mi *MessageInfo) init() {
+	// This function is called in the hot path. Inline the sync.Once logic,
+	// since allocating a closure for Once.Do is expensive.
+	// Keep init small to ensure that it can be inlined.
+	if atomic.LoadUint32(&mi.initDone) == 0 {
+		mi.initOnce()
+	}
+}
+
+func (mi *MessageInfo) initOnce() {
+	mi.initMu.Lock()
+	defer mi.initMu.Unlock()
+	if mi.initDone == 1 {
+		return
+	}
+
+	t := mi.GoReflectType
+	if t.Kind() != reflect.Ptr && t.Elem().Kind() != reflect.Struct {
+		panic(fmt.Sprintf("got %v, want *struct kind", t))
+	}
+	t = t.Elem()
+
+	si := mi.makeStructInfo(t)
+	mi.makeReflectFuncs(t, si)
+	mi.makeCoderMethods(t, si)
+
+	atomic.StoreUint32(&mi.initDone, 1)
+}
+
+// getPointer returns the pointer for a message, which should be of
+// the type of the MessageInfo. If the message is of a different type,
+// it returns ok==false.
+func (mi *MessageInfo) getPointer(m pref.Message) (p pointer, ok bool) {
+	switch m := m.(type) {
+	case *messageState:
+		return m.pointer(), m.messageInfo() == mi
+	case *messageReflectWrapper:
+		return m.pointer(), m.messageInfo() == mi
+	}
+	return pointer{}, false
+}
+
+type (
+	SizeCache       = int32
+	WeakFields      = map[int32]protoreflect.ProtoMessage
+	UnknownFields   = []byte
+	ExtensionFields = map[int32]ExtensionField
+)
+
+var (
+	sizecacheType       = reflect.TypeOf(SizeCache(0))
+	weakFieldsType      = reflect.TypeOf(WeakFields(nil))
+	unknownFieldsType   = reflect.TypeOf(UnknownFields(nil))
+	extensionFieldsType = reflect.TypeOf(ExtensionFields(nil))
+)
+
+type structInfo struct {
+	sizecacheOffset offset
+	weakOffset      offset
+	unknownOffset   offset
+	extensionOffset offset
+
+	fieldsByNumber        map[pref.FieldNumber]reflect.StructField
+	oneofsByName          map[pref.Name]reflect.StructField
+	oneofWrappersByType   map[reflect.Type]pref.FieldNumber
+	oneofWrappersByNumber map[pref.FieldNumber]reflect.Type
+}
+
+func (mi *MessageInfo) makeStructInfo(t reflect.Type) structInfo {
+	si := structInfo{
+		sizecacheOffset: invalidOffset,
+		weakOffset:      invalidOffset,
+		unknownOffset:   invalidOffset,
+		extensionOffset: invalidOffset,
+
+		fieldsByNumber:        map[pref.FieldNumber]reflect.StructField{},
+		oneofsByName:          map[pref.Name]reflect.StructField{},
+		oneofWrappersByType:   map[reflect.Type]pref.FieldNumber{},
+		oneofWrappersByNumber: map[pref.FieldNumber]reflect.Type{},
+	}
+
+fieldLoop:
+	for i := 0; i < t.NumField(); i++ {
+		switch f := t.Field(i); f.Name {
+		case genid.SizeCache_goname, genid.SizeCacheA_goname:
+			if f.Type == sizecacheType {
+				si.sizecacheOffset = offsetOf(f, mi.Exporter)
+			}
+		case genid.WeakFields_goname, genid.WeakFieldsA_goname:
+			if f.Type == weakFieldsType {
+				si.weakOffset = offsetOf(f, mi.Exporter)
+			}
+		case genid.UnknownFields_goname, genid.UnknownFieldsA_goname:
+			if f.Type == unknownFieldsType {
+				si.unknownOffset = offsetOf(f, mi.Exporter)
+			}
+		case genid.ExtensionFields_goname, genid.ExtensionFieldsA_goname, genid.ExtensionFieldsB_goname:
+			if f.Type == extensionFieldsType {
+				si.extensionOffset = offsetOf(f, mi.Exporter)
+			}
+		default:
+			for _, s := range strings.Split(f.Tag.Get("protobuf"), ",") {
+				if len(s) > 0 && strings.Trim(s, "0123456789") == "" {
+					n, _ := strconv.ParseUint(s, 10, 64)
+					si.fieldsByNumber[pref.FieldNumber(n)] = f
+					continue fieldLoop
+				}
+			}
+			if s := f.Tag.Get("protobuf_oneof"); len(s) > 0 {
+				si.oneofsByName[pref.Name(s)] = f
+				continue fieldLoop
+			}
+		}
+	}
+
+	// Derive a mapping of oneof wrappers to fields.
+	oneofWrappers := mi.OneofWrappers
+	for _, method := range []string{"XXX_OneofFuncs", "XXX_OneofWrappers"} {
+		if fn, ok := reflect.PtrTo(t).MethodByName(method); ok {
+			for _, v := range fn.Func.Call([]reflect.Value{reflect.Zero(fn.Type.In(0))}) {
+				if vs, ok := v.Interface().([]interface{}); ok {
+					oneofWrappers = vs
+				}
+			}
+		}
+	}
+	for _, v := range oneofWrappers {
+		tf := reflect.TypeOf(v).Elem()
+		f := tf.Field(0)
+		for _, s := range strings.Split(f.Tag.Get("protobuf"), ",") {
+			if len(s) > 0 && strings.Trim(s, "0123456789") == "" {
+				n, _ := strconv.ParseUint(s, 10, 64)
+				si.oneofWrappersByType[tf] = pref.FieldNumber(n)
+				si.oneofWrappersByNumber[pref.FieldNumber(n)] = tf
+				break
+			}
+		}
+	}
+
+	return si
+}
+
+func (mi *MessageInfo) New() protoreflect.Message {
+	return mi.MessageOf(reflect.New(mi.GoReflectType.Elem()).Interface())
+}
+func (mi *MessageInfo) Zero() protoreflect.Message {
+	return mi.MessageOf(reflect.Zero(mi.GoReflectType).Interface())
+}
+func (mi *MessageInfo) Descriptor() protoreflect.MessageDescriptor { return mi.Desc }

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

@@ -0,0 +1,364 @@
+// Copyright 2019 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package impl
+
+import (
+	"fmt"
+	"reflect"
+
+	"google.golang.org/protobuf/internal/pragma"
+	pref "google.golang.org/protobuf/reflect/protoreflect"
+)
+
+type reflectMessageInfo struct {
+	fields map[pref.FieldNumber]*fieldInfo
+	oneofs map[pref.Name]*oneofInfo
+
+	// denseFields is a subset of fields where:
+	//	0 < fieldDesc.Number() < len(denseFields)
+	// It provides faster access to the fieldInfo, but may be incomplete.
+	denseFields []*fieldInfo
+
+	// rangeInfos is a list of all fields (not belonging to a oneof) and oneofs.
+	rangeInfos []interface{} // either *fieldInfo or *oneofInfo
+
+	getUnknown   func(pointer) pref.RawFields
+	setUnknown   func(pointer, pref.RawFields)
+	extensionMap func(pointer) *extensionMap
+
+	nilMessage atomicNilMessage
+}
+
+// makeReflectFuncs generates the set of functions to support reflection.
+func (mi *MessageInfo) makeReflectFuncs(t reflect.Type, si structInfo) {
+	mi.makeKnownFieldsFunc(si)
+	mi.makeUnknownFieldsFunc(t, si)
+	mi.makeExtensionFieldsFunc(t, si)
+}
+
+// makeKnownFieldsFunc generates functions for operations that can be performed
+// on each protobuf message field. It takes in a reflect.Type representing the
+// Go struct and matches message fields with struct fields.
+//
+// This code assumes that the struct is well-formed and panics if there are
+// any discrepancies.
+func (mi *MessageInfo) makeKnownFieldsFunc(si structInfo) {
+	mi.fields = map[pref.FieldNumber]*fieldInfo{}
+	md := mi.Desc
+	fds := md.Fields()
+	for i := 0; i < fds.Len(); i++ {
+		fd := fds.Get(i)
+		fs := si.fieldsByNumber[fd.Number()]
+		var fi fieldInfo
+		switch {
+		case fd.ContainingOneof() != nil && !fd.ContainingOneof().IsSynthetic():
+			fi = fieldInfoForOneof(fd, si.oneofsByName[fd.ContainingOneof().Name()], mi.Exporter, si.oneofWrappersByNumber[fd.Number()])
+		case fd.IsMap():
+			fi = fieldInfoForMap(fd, fs, mi.Exporter)
+		case fd.IsList():
+			fi = fieldInfoForList(fd, fs, mi.Exporter)
+		case fd.IsWeak():
+			fi = fieldInfoForWeakMessage(fd, si.weakOffset)
+		case fd.Kind() == pref.MessageKind || fd.Kind() == pref.GroupKind:
+			fi = fieldInfoForMessage(fd, fs, mi.Exporter)
+		default:
+			fi = fieldInfoForScalar(fd, fs, mi.Exporter)
+		}
+		mi.fields[fd.Number()] = &fi
+	}
+
+	mi.oneofs = map[pref.Name]*oneofInfo{}
+	for i := 0; i < md.Oneofs().Len(); i++ {
+		od := md.Oneofs().Get(i)
+		mi.oneofs[od.Name()] = makeOneofInfo(od, si, mi.Exporter)
+	}
+
+	mi.denseFields = make([]*fieldInfo, fds.Len()*2)
+	for i := 0; i < fds.Len(); i++ {
+		if fd := fds.Get(i); int(fd.Number()) < len(mi.denseFields) {
+			mi.denseFields[fd.Number()] = mi.fields[fd.Number()]
+		}
+	}
+
+	for i := 0; i < fds.Len(); {
+		fd := fds.Get(i)
+		if od := fd.ContainingOneof(); od != nil && !od.IsSynthetic() {
+			mi.rangeInfos = append(mi.rangeInfos, mi.oneofs[od.Name()])
+			i += od.Fields().Len()
+		} else {
+			mi.rangeInfos = append(mi.rangeInfos, mi.fields[fd.Number()])
+			i++
+		}
+	}
+}
+
+func (mi *MessageInfo) makeUnknownFieldsFunc(t reflect.Type, si structInfo) {
+	mi.getUnknown = func(pointer) pref.RawFields { return nil }
+	mi.setUnknown = func(pointer, pref.RawFields) { return }
+	if si.unknownOffset.IsValid() {
+		mi.getUnknown = func(p pointer) pref.RawFields {
+			if p.IsNil() {
+				return nil
+			}
+			rv := p.Apply(si.unknownOffset).AsValueOf(unknownFieldsType)
+			return pref.RawFields(*rv.Interface().(*[]byte))
+		}
+		mi.setUnknown = func(p pointer, b pref.RawFields) {
+			if p.IsNil() {
+				panic("invalid SetUnknown on nil Message")
+			}
+			rv := p.Apply(si.unknownOffset).AsValueOf(unknownFieldsType)
+			*rv.Interface().(*[]byte) = []byte(b)
+		}
+	} else {
+		mi.getUnknown = func(pointer) pref.RawFields {
+			return nil
+		}
+		mi.setUnknown = func(p pointer, _ pref.RawFields) {
+			if p.IsNil() {
+				panic("invalid SetUnknown on nil Message")
+			}
+		}
+	}
+}
+
+func (mi *MessageInfo) makeExtensionFieldsFunc(t reflect.Type, si structInfo) {
+	if si.extensionOffset.IsValid() {
+		mi.extensionMap = func(p pointer) *extensionMap {
+			if p.IsNil() {
+				return (*extensionMap)(nil)
+			}
+			v := p.Apply(si.extensionOffset).AsValueOf(extensionFieldsType)
+			return (*extensionMap)(v.Interface().(*map[int32]ExtensionField))
+		}
+	} else {
+		mi.extensionMap = func(pointer) *extensionMap {
+			return (*extensionMap)(nil)
+		}
+	}
+}
+
+type extensionMap map[int32]ExtensionField
+
+func (m *extensionMap) Range(f func(pref.FieldDescriptor, pref.Value) bool) {
+	if m != nil {
+		for _, x := range *m {
+			xd := x.Type().TypeDescriptor()
+			v := x.Value()
+			if xd.IsList() && v.List().Len() == 0 {
+				continue
+			}
+			if !f(xd, v) {
+				return
+			}
+		}
+	}
+}
+func (m *extensionMap) Has(xt pref.ExtensionType) (ok bool) {
+	if m == nil {
+		return false
+	}
+	xd := xt.TypeDescriptor()
+	x, ok := (*m)[int32(xd.Number())]
+	if !ok {
+		return false
+	}
+	switch {
+	case xd.IsList():
+		return x.Value().List().Len() > 0
+	case xd.IsMap():
+		return x.Value().Map().Len() > 0
+	case xd.Message() != nil:
+		return x.Value().Message().IsValid()
+	}
+	return true
+}
+func (m *extensionMap) Clear(xt pref.ExtensionType) {
+	delete(*m, int32(xt.TypeDescriptor().Number()))
+}
+func (m *extensionMap) Get(xt pref.ExtensionType) pref.Value {
+	xd := xt.TypeDescriptor()
+	if m != nil {
+		if x, ok := (*m)[int32(xd.Number())]; ok {
+			return x.Value()
+		}
+	}
+	return xt.Zero()
+}
+func (m *extensionMap) Set(xt pref.ExtensionType, v pref.Value) {
+	xd := xt.TypeDescriptor()
+	isValid := true
+	switch {
+	case !xt.IsValidValue(v):
+		isValid = false
+	case xd.IsList():
+		isValid = v.List().IsValid()
+	case xd.IsMap():
+		isValid = v.Map().IsValid()
+	case xd.Message() != nil:
+		isValid = v.Message().IsValid()
+	}
+	if !isValid {
+		panic(fmt.Sprintf("%v: assigning invalid value", xt.TypeDescriptor().FullName()))
+	}
+
+	if *m == nil {
+		*m = make(map[int32]ExtensionField)
+	}
+	var x ExtensionField
+	x.Set(xt, v)
+	(*m)[int32(xd.Number())] = x
+}
+func (m *extensionMap) Mutable(xt pref.ExtensionType) pref.Value {
+	xd := xt.TypeDescriptor()
+	if xd.Kind() != pref.MessageKind && xd.Kind() != pref.GroupKind && !xd.IsList() && !xd.IsMap() {
+		panic("invalid Mutable on field with non-composite type")
+	}
+	if x, ok := (*m)[int32(xd.Number())]; ok {
+		return x.Value()
+	}
+	v := xt.New()
+	m.Set(xt, v)
+	return v
+}
+
+// MessageState is a data structure that is nested as the first field in a
+// concrete message. It provides a way to implement the ProtoReflect method
+// in an allocation-free way without needing to have a shadow Go type generated
+// for every message type. This technique only works using unsafe.
+//
+//
+// Example generated code:
+//
+//	type M struct {
+//		state protoimpl.MessageState
+//
+//		Field1 int32
+//		Field2 string
+//		Field3 *BarMessage
+//		...
+//	}
+//
+//	func (m *M) ProtoReflect() protoreflect.Message {
+//		mi := &file_fizz_buzz_proto_msgInfos[5]
+//		if protoimpl.UnsafeEnabled && m != nil {
+//			ms := protoimpl.X.MessageStateOf(Pointer(m))
+//			if ms.LoadMessageInfo() == nil {
+//				ms.StoreMessageInfo(mi)
+//			}
+//			return ms
+//		}
+//		return mi.MessageOf(m)
+//	}
+//
+// The MessageState type holds a *MessageInfo, which must be atomically set to
+// the message info associated with a given message instance.
+// By unsafely converting a *M into a *MessageState, the MessageState object
+// has access to all the information needed to implement protobuf reflection.
+// It has access to the message info as its first field, and a pointer to the
+// MessageState is identical to a pointer to the concrete message value.
+//
+//
+// Requirements:
+//	• The type M must implement protoreflect.ProtoMessage.
+//	• The address of m must not be nil.
+//	• The address of m and the address of m.state must be equal,
+//	even though they are different Go types.
+type MessageState struct {
+	pragma.NoUnkeyedLiterals
+	pragma.DoNotCompare
+	pragma.DoNotCopy
+
+	atomicMessageInfo *MessageInfo
+}
+
+type messageState MessageState
+
+var (
+	_ pref.Message = (*messageState)(nil)
+	_ unwrapper    = (*messageState)(nil)
+)
+
+// messageDataType is a tuple of a pointer to the message data and
+// a pointer to the message type. It is a generalized way of providing a
+// reflective view over a message instance. The disadvantage of this approach
+// is the need to allocate this tuple of 16B.
+type messageDataType struct {
+	p  pointer
+	mi *MessageInfo
+}
+
+type (
+	messageReflectWrapper messageDataType
+	messageIfaceWrapper   messageDataType
+)
+
+var (
+	_ pref.Message      = (*messageReflectWrapper)(nil)
+	_ unwrapper         = (*messageReflectWrapper)(nil)
+	_ pref.ProtoMessage = (*messageIfaceWrapper)(nil)
+	_ unwrapper         = (*messageIfaceWrapper)(nil)
+)
+
+// MessageOf returns a reflective view over a message. The input must be a
+// pointer to a named Go struct. If the provided type has a ProtoReflect method,
+// it must be implemented by calling this method.
+func (mi *MessageInfo) MessageOf(m interface{}) pref.Message {
+	// TODO: Switch the input to be an opaque Pointer.
+	if reflect.TypeOf(m) != mi.GoReflectType {
+		panic(fmt.Sprintf("type mismatch: got %T, want %v", m, mi.GoReflectType))
+	}
+	p := pointerOfIface(m)
+	if p.IsNil() {
+		return mi.nilMessage.Init(mi)
+	}
+	return &messageReflectWrapper{p, mi}
+}
+
+func (m *messageReflectWrapper) pointer() pointer          { return m.p }
+func (m *messageReflectWrapper) messageInfo() *MessageInfo { return m.mi }
+
+func (m *messageIfaceWrapper) ProtoReflect() pref.Message {
+	return (*messageReflectWrapper)(m)
+}
+func (m *messageIfaceWrapper) protoUnwrap() interface{} {
+	return m.p.AsIfaceOf(m.mi.GoReflectType.Elem())
+}
+
+// checkField verifies that the provided field descriptor is valid.
+// Exactly one of the returned values is populated.
+func (mi *MessageInfo) checkField(fd pref.FieldDescriptor) (*fieldInfo, pref.ExtensionType) {
+	var fi *fieldInfo
+	if n := fd.Number(); 0 < n && int(n) < len(mi.denseFields) {
+		fi = mi.denseFields[n]
+	} else {
+		fi = mi.fields[n]
+	}
+	if fi != nil {
+		if fi.fieldDesc != fd {
+			if got, want := fd.FullName(), fi.fieldDesc.FullName(); got != want {
+				panic(fmt.Sprintf("mismatching field: got %v, want %v", got, want))
+			}
+			panic(fmt.Sprintf("mismatching field: %v", fd.FullName()))
+		}
+		return fi, nil
+	}
+
+	if fd.IsExtension() {
+		if got, want := fd.ContainingMessage().FullName(), mi.Desc.FullName(); got != want {
+			// TODO: Should this be exact containing message descriptor match?
+			panic(fmt.Sprintf("extension %v has mismatching containing message: got %v, want %v", fd.FullName(), got, want))
+		}
+		if !mi.Desc.ExtensionRanges().Has(fd.Number()) {
+			panic(fmt.Sprintf("extension %v extends %v outside the extension range", fd.FullName(), mi.Desc.FullName()))
+		}
+		xtd, ok := fd.(pref.ExtensionTypeDescriptor)
+		if !ok {
+			panic(fmt.Sprintf("extension %v does not implement protoreflect.ExtensionTypeDescriptor", fd.FullName()))
+		}
+		return nil, xtd.Type()
+	}
+	panic(fmt.Sprintf("field %v is invalid", fd.FullName()))
+}

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

@@ -0,0 +1,466 @@
+// Copyright 2018 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package impl
+
+import (
+	"fmt"
+	"math"
+	"reflect"
+	"sync"
+
+	"google.golang.org/protobuf/internal/flags"
+	pref "google.golang.org/protobuf/reflect/protoreflect"
+	preg "google.golang.org/protobuf/reflect/protoregistry"
+)
+
+type fieldInfo struct {
+	fieldDesc pref.FieldDescriptor
+
+	// These fields are used for protobuf reflection support.
+	has        func(pointer) bool
+	clear      func(pointer)
+	get        func(pointer) pref.Value
+	set        func(pointer, pref.Value)
+	mutable    func(pointer) pref.Value
+	newMessage func() pref.Message
+	newField   func() pref.Value
+}
+
+func fieldInfoForOneof(fd pref.FieldDescriptor, fs reflect.StructField, x exporter, ot reflect.Type) fieldInfo {
+	ft := fs.Type
+	if ft.Kind() != reflect.Interface {
+		panic(fmt.Sprintf("field %v has invalid type: got %v, want interface kind", fd.FullName(), ft))
+	}
+	if ot.Kind() != reflect.Struct {
+		panic(fmt.Sprintf("field %v has invalid type: got %v, want struct kind", fd.FullName(), ot))
+	}
+	if !reflect.PtrTo(ot).Implements(ft) {
+		panic(fmt.Sprintf("field %v has invalid type: %v does not implement %v", fd.FullName(), ot, ft))
+	}
+	conv := NewConverter(ot.Field(0).Type, fd)
+	isMessage := fd.Message() != nil
+
+	// TODO: Implement unsafe fast path?
+	fieldOffset := offsetOf(fs, x)
+	return fieldInfo{
+		// NOTE: The logic below intentionally assumes that oneof fields are
+		// well-formatted. That is, the oneof interface never contains a
+		// typed nil pointer to one of the wrapper structs.
+
+		fieldDesc: fd,
+		has: func(p pointer) bool {
+			if p.IsNil() {
+				return false
+			}
+			rv := p.Apply(fieldOffset).AsValueOf(fs.Type).Elem()
+			if rv.IsNil() || rv.Elem().Type().Elem() != ot || rv.Elem().IsNil() {
+				return false
+			}
+			return true
+		},
+		clear: func(p pointer) {
+			rv := p.Apply(fieldOffset).AsValueOf(fs.Type).Elem()
+			if rv.IsNil() || rv.Elem().Type().Elem() != ot {
+				// NOTE: We intentionally don't check for rv.Elem().IsNil()
+				// so that (*OneofWrapperType)(nil) gets cleared to nil.
+				return
+			}
+			rv.Set(reflect.Zero(rv.Type()))
+		},
+		get: func(p pointer) pref.Value {
+			if p.IsNil() {
+				return conv.Zero()
+			}
+			rv := p.Apply(fieldOffset).AsValueOf(fs.Type).Elem()
+			if rv.IsNil() || rv.Elem().Type().Elem() != ot || rv.Elem().IsNil() {
+				return conv.Zero()
+			}
+			rv = rv.Elem().Elem().Field(0)
+			return conv.PBValueOf(rv)
+		},
+		set: func(p pointer, v pref.Value) {
+			rv := p.Apply(fieldOffset).AsValueOf(fs.Type).Elem()
+			if rv.IsNil() || rv.Elem().Type().Elem() != ot || rv.Elem().IsNil() {
+				rv.Set(reflect.New(ot))
+			}
+			rv = rv.Elem().Elem().Field(0)
+			rv.Set(conv.GoValueOf(v))
+		},
+		mutable: func(p pointer) pref.Value {
+			if !isMessage {
+				panic(fmt.Sprintf("field %v with invalid Mutable call on field with non-composite type", fd.FullName()))
+			}
+			rv := p.Apply(fieldOffset).AsValueOf(fs.Type).Elem()
+			if rv.IsNil() || rv.Elem().Type().Elem() != ot || rv.Elem().IsNil() {
+				rv.Set(reflect.New(ot))
+			}
+			rv = rv.Elem().Elem().Field(0)
+			if rv.IsNil() {
+				rv.Set(conv.GoValueOf(pref.ValueOfMessage(conv.New().Message())))
+			}
+			return conv.PBValueOf(rv)
+		},
+		newMessage: func() pref.Message {
+			return conv.New().Message()
+		},
+		newField: func() pref.Value {
+			return conv.New()
+		},
+	}
+}
+
+func fieldInfoForMap(fd pref.FieldDescriptor, fs reflect.StructField, x exporter) fieldInfo {
+	ft := fs.Type
+	if ft.Kind() != reflect.Map {
+		panic(fmt.Sprintf("field %v has invalid type: got %v, want map kind", fd.FullName(), ft))
+	}
+	conv := NewConverter(ft, fd)
+
+	// TODO: Implement unsafe fast path?
+	fieldOffset := offsetOf(fs, x)
+	return fieldInfo{
+		fieldDesc: fd,
+		has: func(p pointer) bool {
+			if p.IsNil() {
+				return false
+			}
+			rv := p.Apply(fieldOffset).AsValueOf(fs.Type).Elem()
+			return rv.Len() > 0
+		},
+		clear: func(p pointer) {
+			rv := p.Apply(fieldOffset).AsValueOf(fs.Type).Elem()
+			rv.Set(reflect.Zero(rv.Type()))
+		},
+		get: func(p pointer) pref.Value {
+			if p.IsNil() {
+				return conv.Zero()
+			}
+			rv := p.Apply(fieldOffset).AsValueOf(fs.Type).Elem()
+			if rv.Len() == 0 {
+				return conv.Zero()
+			}
+			return conv.PBValueOf(rv)
+		},
+		set: func(p pointer, v pref.Value) {
+			rv := p.Apply(fieldOffset).AsValueOf(fs.Type).Elem()
+			pv := conv.GoValueOf(v)
+			if pv.IsNil() {
+				panic(fmt.Sprintf("map field %v cannot be set with read-only value", fd.FullName()))
+			}
+			rv.Set(pv)
+		},
+		mutable: func(p pointer) pref.Value {
+			v := p.Apply(fieldOffset).AsValueOf(fs.Type).Elem()
+			if v.IsNil() {
+				v.Set(reflect.MakeMap(fs.Type))
+			}
+			return conv.PBValueOf(v)
+		},
+		newField: func() pref.Value {
+			return conv.New()
+		},
+	}
+}
+
+func fieldInfoForList(fd pref.FieldDescriptor, fs reflect.StructField, x exporter) fieldInfo {
+	ft := fs.Type
+	if ft.Kind() != reflect.Slice {
+		panic(fmt.Sprintf("field %v has invalid type: got %v, want slice kind", fd.FullName(), ft))
+	}
+	conv := NewConverter(reflect.PtrTo(ft), fd)
+
+	// TODO: Implement unsafe fast path?
+	fieldOffset := offsetOf(fs, x)
+	return fieldInfo{
+		fieldDesc: fd,
+		has: func(p pointer) bool {
+			if p.IsNil() {
+				return false
+			}
+			rv := p.Apply(fieldOffset).AsValueOf(fs.Type).Elem()
+			return rv.Len() > 0
+		},
+		clear: func(p pointer) {
+			rv := p.Apply(fieldOffset).AsValueOf(fs.Type).Elem()
+			rv.Set(reflect.Zero(rv.Type()))
+		},
+		get: func(p pointer) pref.Value {
+			if p.IsNil() {
+				return conv.Zero()
+			}
+			rv := p.Apply(fieldOffset).AsValueOf(fs.Type)
+			if rv.Elem().Len() == 0 {
+				return conv.Zero()
+			}
+			return conv.PBValueOf(rv)
+		},
+		set: func(p pointer, v pref.Value) {
+			rv := p.Apply(fieldOffset).AsValueOf(fs.Type).Elem()
+			pv := conv.GoValueOf(v)
+			if pv.IsNil() {
+				panic(fmt.Sprintf("list field %v cannot be set with read-only value", fd.FullName()))
+			}
+			rv.Set(pv.Elem())
+		},
+		mutable: func(p pointer) pref.Value {
+			v := p.Apply(fieldOffset).AsValueOf(fs.Type)
+			return conv.PBValueOf(v)
+		},
+		newField: func() pref.Value {
+			return conv.New()
+		},
+	}
+}
+
+var (
+	nilBytes   = reflect.ValueOf([]byte(nil))
+	emptyBytes = reflect.ValueOf([]byte{})
+)
+
+func fieldInfoForScalar(fd pref.FieldDescriptor, fs reflect.StructField, x exporter) fieldInfo {
+	ft := fs.Type
+	nullable := fd.HasPresence()
+	isBytes := ft.Kind() == reflect.Slice && ft.Elem().Kind() == reflect.Uint8
+	if nullable {
+		if ft.Kind() != reflect.Ptr && ft.Kind() != reflect.Slice {
+			panic(fmt.Sprintf("field %v has invalid type: got %v, want pointer", fd.FullName(), ft))
+		}
+		if ft.Kind() == reflect.Ptr {
+			ft = ft.Elem()
+		}
+	}
+	conv := NewConverter(ft, fd)
+
+	// TODO: Implement unsafe fast path?
+	fieldOffset := offsetOf(fs, x)
+	return fieldInfo{
+		fieldDesc: fd,
+		has: func(p pointer) bool {
+			if p.IsNil() {
+				return false
+			}
+			rv := p.Apply(fieldOffset).AsValueOf(fs.Type).Elem()
+			if nullable {
+				return !rv.IsNil()
+			}
+			switch rv.Kind() {
+			case reflect.Bool:
+				return rv.Bool()
+			case reflect.Int32, reflect.Int64:
+				return rv.Int() != 0
+			case reflect.Uint32, reflect.Uint64:
+				return rv.Uint() != 0
+			case reflect.Float32, reflect.Float64:
+				return rv.Float() != 0 || math.Signbit(rv.Float())
+			case reflect.String, reflect.Slice:
+				return rv.Len() > 0
+			default:
+				panic(fmt.Sprintf("field %v has invalid type: %v", fd.FullName(), rv.Type())) // should never happen
+			}
+		},
+		clear: func(p pointer) {
+			rv := p.Apply(fieldOffset).AsValueOf(fs.Type).Elem()
+			rv.Set(reflect.Zero(rv.Type()))
+		},
+		get: func(p pointer) pref.Value {
+			if p.IsNil() {
+				return conv.Zero()
+			}
+			rv := p.Apply(fieldOffset).AsValueOf(fs.Type).Elem()
+			if nullable {
+				if rv.IsNil() {
+					return conv.Zero()
+				}
+				if rv.Kind() == reflect.Ptr {
+					rv = rv.Elem()
+				}
+			}
+			return conv.PBValueOf(rv)
+		},
+		set: func(p pointer, v pref.Value) {
+			rv := p.Apply(fieldOffset).AsValueOf(fs.Type).Elem()
+			if nullable && rv.Kind() == reflect.Ptr {
+				if rv.IsNil() {
+					rv.Set(reflect.New(ft))
+				}
+				rv = rv.Elem()
+			}
+			rv.Set(conv.GoValueOf(v))
+			if isBytes && rv.Len() == 0 {
+				if nullable {
+					rv.Set(emptyBytes) // preserve presence
+				} else {
+					rv.Set(nilBytes) // do not preserve presence
+				}
+			}
+		},
+		newField: func() pref.Value {
+			return conv.New()
+		},
+	}
+}
+
+func fieldInfoForWeakMessage(fd pref.FieldDescriptor, weakOffset offset) fieldInfo {
+	if !flags.ProtoLegacy {
+		panic("no support for proto1 weak fields")
+	}
+
+	var once sync.Once
+	var messageType pref.MessageType
+	lazyInit := func() {
+		once.Do(func() {
+			messageName := fd.Message().FullName()
+			messageType, _ = preg.GlobalTypes.FindMessageByName(messageName)
+			if messageType == nil {
+				panic(fmt.Sprintf("weak message %v for field %v is not linked in", messageName, fd.FullName()))
+			}
+		})
+	}
+
+	num := fd.Number()
+	return fieldInfo{
+		fieldDesc: fd,
+		has: func(p pointer) bool {
+			if p.IsNil() {
+				return false
+			}
+			_, ok := p.Apply(weakOffset).WeakFields().get(num)
+			return ok
+		},
+		clear: func(p pointer) {
+			p.Apply(weakOffset).WeakFields().clear(num)
+		},
+		get: func(p pointer) pref.Value {
+			lazyInit()
+			if p.IsNil() {
+				return pref.ValueOfMessage(messageType.Zero())
+			}
+			m, ok := p.Apply(weakOffset).WeakFields().get(num)
+			if !ok {
+				return pref.ValueOfMessage(messageType.Zero())
+			}
+			return pref.ValueOfMessage(m.ProtoReflect())
+		},
+		set: func(p pointer, v pref.Value) {
+			lazyInit()
+			m := v.Message()
+			if m.Descriptor() != messageType.Descriptor() {
+				if got, want := m.Descriptor().FullName(), messageType.Descriptor().FullName(); got != want {
+					panic(fmt.Sprintf("field %v has mismatching message descriptor: got %v, want %v", fd.FullName(), got, want))
+				}
+				panic(fmt.Sprintf("field %v has mismatching message descriptor: %v", fd.FullName(), m.Descriptor().FullName()))
+			}
+			p.Apply(weakOffset).WeakFields().set(num, m.Interface())
+		},
+		mutable: func(p pointer) pref.Value {
+			lazyInit()
+			fs := p.Apply(weakOffset).WeakFields()
+			m, ok := fs.get(num)
+			if !ok {
+				m = messageType.New().Interface()
+				fs.set(num, m)
+			}
+			return pref.ValueOfMessage(m.ProtoReflect())
+		},
+		newMessage: func() pref.Message {
+			lazyInit()
+			return messageType.New()
+		},
+		newField: func() pref.Value {
+			lazyInit()
+			return pref.ValueOfMessage(messageType.New())
+		},
+	}
+}
+
+func fieldInfoForMessage(fd pref.FieldDescriptor, fs reflect.StructField, x exporter) fieldInfo {
+	ft := fs.Type
+	conv := NewConverter(ft, fd)
+
+	// TODO: Implement unsafe fast path?
+	fieldOffset := offsetOf(fs, x)
+	return fieldInfo{
+		fieldDesc: fd,
+		has: func(p pointer) bool {
+			if p.IsNil() {
+				return false
+			}
+			rv := p.Apply(fieldOffset).AsValueOf(fs.Type).Elem()
+			return !rv.IsNil()
+		},
+		clear: func(p pointer) {
+			rv := p.Apply(fieldOffset).AsValueOf(fs.Type).Elem()
+			rv.Set(reflect.Zero(rv.Type()))
+		},
+		get: func(p pointer) pref.Value {
+			if p.IsNil() {
+				return conv.Zero()
+			}
+			rv := p.Apply(fieldOffset).AsValueOf(fs.Type).Elem()
+			return conv.PBValueOf(rv)
+		},
+		set: func(p pointer, v pref.Value) {
+			rv := p.Apply(fieldOffset).AsValueOf(fs.Type).Elem()
+			rv.Set(conv.GoValueOf(v))
+			if rv.IsNil() {
+				panic(fmt.Sprintf("field %v has invalid nil pointer", fd.FullName()))
+			}
+		},
+		mutable: func(p pointer) pref.Value {
+			rv := p.Apply(fieldOffset).AsValueOf(fs.Type).Elem()
+			if rv.IsNil() {
+				rv.Set(conv.GoValueOf(conv.New()))
+			}
+			return conv.PBValueOf(rv)
+		},
+		newMessage: func() pref.Message {
+			return conv.New().Message()
+		},
+		newField: func() pref.Value {
+			return conv.New()
+		},
+	}
+}
+
+type oneofInfo struct {
+	oneofDesc pref.OneofDescriptor
+	which     func(pointer) pref.FieldNumber
+}
+
+func makeOneofInfo(od pref.OneofDescriptor, si structInfo, x exporter) *oneofInfo {
+	oi := &oneofInfo{oneofDesc: od}
+	if od.IsSynthetic() {
+		fs := si.fieldsByNumber[od.Fields().Get(0).Number()]
+		fieldOffset := offsetOf(fs, x)
+		oi.which = func(p pointer) pref.FieldNumber {
+			if p.IsNil() {
+				return 0
+			}
+			rv := p.Apply(fieldOffset).AsValueOf(fs.Type).Elem()
+			if rv.IsNil() { // valid on either *T or []byte
+				return 0
+			}
+			return od.Fields().Get(0).Number()
+		}
+	} else {
+		fs := si.oneofsByName[od.Name()]
+		fieldOffset := offsetOf(fs, x)
+		oi.which = func(p pointer) pref.FieldNumber {
+			if p.IsNil() {
+				return 0
+			}
+			rv := p.Apply(fieldOffset).AsValueOf(fs.Type).Elem()
+			if rv.IsNil() {
+				return 0
+			}
+			rv = rv.Elem()
+			if rv.IsNil() {
+				return 0
+			}
+			return si.oneofWrappersByType[rv.Type().Elem()]
+		}
+	}
+	return oi
+}

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

@@ -0,0 +1,249 @@
+// Copyright 2018 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Code generated by generate-types. DO NOT EDIT.
+
+package impl
+
+import (
+	"google.golang.org/protobuf/reflect/protoreflect"
+	"google.golang.org/protobuf/runtime/protoiface"
+)
+
+func (m *messageState) Descriptor() protoreflect.MessageDescriptor {
+	return m.messageInfo().Desc
+}
+func (m *messageState) Type() protoreflect.MessageType {
+	return m.messageInfo()
+}
+func (m *messageState) New() protoreflect.Message {
+	return m.messageInfo().New()
+}
+func (m *messageState) Interface() protoreflect.ProtoMessage {
+	return m.protoUnwrap().(protoreflect.ProtoMessage)
+}
+func (m *messageState) protoUnwrap() interface{} {
+	return m.pointer().AsIfaceOf(m.messageInfo().GoReflectType.Elem())
+}
+func (m *messageState) ProtoMethods() *protoiface.Methods {
+	m.messageInfo().init()
+	return &m.messageInfo().methods
+}
+
+// ProtoMessageInfo is a pseudo-internal API for allowing the v1 code
+// to be able to retrieve a v2 MessageInfo struct.
+//
+// WARNING: This method is exempt from the compatibility promise and
+// may be removed in the future without warning.
+func (m *messageState) ProtoMessageInfo() *MessageInfo {
+	return m.messageInfo()
+}
+
+func (m *messageState) Range(f func(protoreflect.FieldDescriptor, protoreflect.Value) bool) {
+	m.messageInfo().init()
+	for _, ri := range m.messageInfo().rangeInfos {
+		switch ri := ri.(type) {
+		case *fieldInfo:
+			if ri.has(m.pointer()) {
+				if !f(ri.fieldDesc, ri.get(m.pointer())) {
+					return
+				}
+			}
+		case *oneofInfo:
+			if n := ri.which(m.pointer()); n > 0 {
+				fi := m.messageInfo().fields[n]
+				if !f(fi.fieldDesc, fi.get(m.pointer())) {
+					return
+				}
+			}
+		}
+	}
+	m.messageInfo().extensionMap(m.pointer()).Range(f)
+}
+func (m *messageState) Has(fd protoreflect.FieldDescriptor) bool {
+	m.messageInfo().init()
+	if fi, xt := m.messageInfo().checkField(fd); fi != nil {
+		return fi.has(m.pointer())
+	} else {
+		return m.messageInfo().extensionMap(m.pointer()).Has(xt)
+	}
+}
+func (m *messageState) Clear(fd protoreflect.FieldDescriptor) {
+	m.messageInfo().init()
+	if fi, xt := m.messageInfo().checkField(fd); fi != nil {
+		fi.clear(m.pointer())
+	} else {
+		m.messageInfo().extensionMap(m.pointer()).Clear(xt)
+	}
+}
+func (m *messageState) Get(fd protoreflect.FieldDescriptor) protoreflect.Value {
+	m.messageInfo().init()
+	if fi, xt := m.messageInfo().checkField(fd); fi != nil {
+		return fi.get(m.pointer())
+	} else {
+		return m.messageInfo().extensionMap(m.pointer()).Get(xt)
+	}
+}
+func (m *messageState) Set(fd protoreflect.FieldDescriptor, v protoreflect.Value) {
+	m.messageInfo().init()
+	if fi, xt := m.messageInfo().checkField(fd); fi != nil {
+		fi.set(m.pointer(), v)
+	} else {
+		m.messageInfo().extensionMap(m.pointer()).Set(xt, v)
+	}
+}
+func (m *messageState) Mutable(fd protoreflect.FieldDescriptor) protoreflect.Value {
+	m.messageInfo().init()
+	if fi, xt := m.messageInfo().checkField(fd); fi != nil {
+		return fi.mutable(m.pointer())
+	} else {
+		return m.messageInfo().extensionMap(m.pointer()).Mutable(xt)
+	}
+}
+func (m *messageState) NewField(fd protoreflect.FieldDescriptor) protoreflect.Value {
+	m.messageInfo().init()
+	if fi, xt := m.messageInfo().checkField(fd); fi != nil {
+		return fi.newField()
+	} else {
+		return xt.New()
+	}
+}
+func (m *messageState) WhichOneof(od protoreflect.OneofDescriptor) protoreflect.FieldDescriptor {
+	m.messageInfo().init()
+	if oi := m.messageInfo().oneofs[od.Name()]; oi != nil && oi.oneofDesc == od {
+		return od.Fields().ByNumber(oi.which(m.pointer()))
+	}
+	panic("invalid oneof descriptor " + string(od.FullName()) + " for message " + string(m.Descriptor().FullName()))
+}
+func (m *messageState) GetUnknown() protoreflect.RawFields {
+	m.messageInfo().init()
+	return m.messageInfo().getUnknown(m.pointer())
+}
+func (m *messageState) SetUnknown(b protoreflect.RawFields) {
+	m.messageInfo().init()
+	m.messageInfo().setUnknown(m.pointer(), b)
+}
+func (m *messageState) IsValid() bool {
+	return !m.pointer().IsNil()
+}
+
+func (m *messageReflectWrapper) Descriptor() protoreflect.MessageDescriptor {
+	return m.messageInfo().Desc
+}
+func (m *messageReflectWrapper) Type() protoreflect.MessageType {
+	return m.messageInfo()
+}
+func (m *messageReflectWrapper) New() protoreflect.Message {
+	return m.messageInfo().New()
+}
+func (m *messageReflectWrapper) Interface() protoreflect.ProtoMessage {
+	if m, ok := m.protoUnwrap().(protoreflect.ProtoMessage); ok {
+		return m
+	}
+	return (*messageIfaceWrapper)(m)
+}
+func (m *messageReflectWrapper) protoUnwrap() interface{} {
+	return m.pointer().AsIfaceOf(m.messageInfo().GoReflectType.Elem())
+}
+func (m *messageReflectWrapper) ProtoMethods() *protoiface.Methods {
+	m.messageInfo().init()
+	return &m.messageInfo().methods
+}
+
+// ProtoMessageInfo is a pseudo-internal API for allowing the v1 code
+// to be able to retrieve a v2 MessageInfo struct.
+//
+// WARNING: This method is exempt from the compatibility promise and
+// may be removed in the future without warning.
+func (m *messageReflectWrapper) ProtoMessageInfo() *MessageInfo {
+	return m.messageInfo()
+}
+
+func (m *messageReflectWrapper) Range(f func(protoreflect.FieldDescriptor, protoreflect.Value) bool) {
+	m.messageInfo().init()
+	for _, ri := range m.messageInfo().rangeInfos {
+		switch ri := ri.(type) {
+		case *fieldInfo:
+			if ri.has(m.pointer()) {
+				if !f(ri.fieldDesc, ri.get(m.pointer())) {
+					return
+				}
+			}
+		case *oneofInfo:
+			if n := ri.which(m.pointer()); n > 0 {
+				fi := m.messageInfo().fields[n]
+				if !f(fi.fieldDesc, fi.get(m.pointer())) {
+					return
+				}
+			}
+		}
+	}
+	m.messageInfo().extensionMap(m.pointer()).Range(f)
+}
+func (m *messageReflectWrapper) Has(fd protoreflect.FieldDescriptor) bool {
+	m.messageInfo().init()
+	if fi, xt := m.messageInfo().checkField(fd); fi != nil {
+		return fi.has(m.pointer())
+	} else {
+		return m.messageInfo().extensionMap(m.pointer()).Has(xt)
+	}
+}
+func (m *messageReflectWrapper) Clear(fd protoreflect.FieldDescriptor) {
+	m.messageInfo().init()
+	if fi, xt := m.messageInfo().checkField(fd); fi != nil {
+		fi.clear(m.pointer())
+	} else {
+		m.messageInfo().extensionMap(m.pointer()).Clear(xt)
+	}
+}
+func (m *messageReflectWrapper) Get(fd protoreflect.FieldDescriptor) protoreflect.Value {
+	m.messageInfo().init()
+	if fi, xt := m.messageInfo().checkField(fd); fi != nil {
+		return fi.get(m.pointer())
+	} else {
+		return m.messageInfo().extensionMap(m.pointer()).Get(xt)
+	}
+}
+func (m *messageReflectWrapper) Set(fd protoreflect.FieldDescriptor, v protoreflect.Value) {
+	m.messageInfo().init()
+	if fi, xt := m.messageInfo().checkField(fd); fi != nil {
+		fi.set(m.pointer(), v)
+	} else {
+		m.messageInfo().extensionMap(m.pointer()).Set(xt, v)
+	}
+}
+func (m *messageReflectWrapper) Mutable(fd protoreflect.FieldDescriptor) protoreflect.Value {
+	m.messageInfo().init()
+	if fi, xt := m.messageInfo().checkField(fd); fi != nil {
+		return fi.mutable(m.pointer())
+	} else {
+		return m.messageInfo().extensionMap(m.pointer()).Mutable(xt)
+	}
+}
+func (m *messageReflectWrapper) NewField(fd protoreflect.FieldDescriptor) protoreflect.Value {
+	m.messageInfo().init()
+	if fi, xt := m.messageInfo().checkField(fd); fi != nil {
+		return fi.newField()
+	} else {
+		return xt.New()
+	}
+}
+func (m *messageReflectWrapper) WhichOneof(od protoreflect.OneofDescriptor) protoreflect.FieldDescriptor {
+	m.messageInfo().init()
+	if oi := m.messageInfo().oneofs[od.Name()]; oi != nil && oi.oneofDesc == od {
+		return od.Fields().ByNumber(oi.which(m.pointer()))
+	}
+	panic("invalid oneof descriptor " + string(od.FullName()) + " for message " + string(m.Descriptor().FullName()))
+}
+func (m *messageReflectWrapper) GetUnknown() protoreflect.RawFields {
+	m.messageInfo().init()
+	return m.messageInfo().getUnknown(m.pointer())
+}
+func (m *messageReflectWrapper) SetUnknown(b protoreflect.RawFields) {
+	m.messageInfo().init()
+	m.messageInfo().setUnknown(m.pointer(), b)
+}
+func (m *messageReflectWrapper) IsValid() bool {
+	return !m.pointer().IsNil()
+}

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

@@ -0,0 +1,177 @@
+// Copyright 2018 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build purego appengine
+
+package impl
+
+import (
+	"fmt"
+	"reflect"
+	"sync"
+)
+
+const UnsafeEnabled = false
+
+// Pointer is an opaque pointer type.
+type Pointer interface{}
+
+// offset represents the offset to a struct field, accessible from a pointer.
+// The offset is the field index into a struct.
+type offset struct {
+	index  int
+	export exporter
+}
+
+// offsetOf returns a field offset for the struct field.
+func offsetOf(f reflect.StructField, x exporter) offset {
+	if len(f.Index) != 1 {
+		panic("embedded structs are not supported")
+	}
+	if f.PkgPath == "" {
+		return offset{index: f.Index[0]} // field is already exported
+	}
+	if x == nil {
+		panic("exporter must be provided for unexported field")
+	}
+	return offset{index: f.Index[0], export: x}
+}
+
+// IsValid reports whether the offset is valid.
+func (f offset) IsValid() bool { return f.index >= 0 }
+
+// invalidOffset is an invalid field offset.
+var invalidOffset = offset{index: -1}
+
+// zeroOffset is a noop when calling pointer.Apply.
+var zeroOffset = offset{index: 0}
+
+// pointer is an abstract representation of a pointer to a struct or field.
+type pointer struct{ v reflect.Value }
+
+// pointerOf returns p as a pointer.
+func pointerOf(p Pointer) pointer {
+	return pointerOfIface(p)
+}
+
+// pointerOfValue returns v as a pointer.
+func pointerOfValue(v reflect.Value) pointer {
+	return pointer{v: v}
+}
+
+// pointerOfIface returns the pointer portion of an interface.
+func pointerOfIface(v interface{}) pointer {
+	return pointer{v: reflect.ValueOf(v)}
+}
+
+// IsNil reports whether the pointer is nil.
+func (p pointer) IsNil() bool {
+	return p.v.IsNil()
+}
+
+// Apply adds an offset to the pointer to derive a new pointer
+// to a specified field. The current pointer must be pointing at a struct.
+func (p pointer) Apply(f offset) pointer {
+	if f.export != nil {
+		if v := reflect.ValueOf(f.export(p.v.Interface(), f.index)); v.IsValid() {
+			return pointer{v: v}
+		}
+	}
+	return pointer{v: p.v.Elem().Field(f.index).Addr()}
+}
+
+// AsValueOf treats p as a pointer to an object of type t and returns the value.
+// It is equivalent to reflect.ValueOf(p.AsIfaceOf(t))
+func (p pointer) AsValueOf(t reflect.Type) reflect.Value {
+	if got := p.v.Type().Elem(); got != t {
+		panic(fmt.Sprintf("invalid type: got %v, want %v", got, t))
+	}
+	return p.v
+}
+
+// AsIfaceOf treats p as a pointer to an object of type t and returns the value.
+// It is equivalent to p.AsValueOf(t).Interface()
+func (p pointer) AsIfaceOf(t reflect.Type) interface{} {
+	return p.AsValueOf(t).Interface()
+}
+
+func (p pointer) Bool() *bool              { return p.v.Interface().(*bool) }
+func (p pointer) BoolPtr() **bool          { return p.v.Interface().(**bool) }
+func (p pointer) BoolSlice() *[]bool       { return p.v.Interface().(*[]bool) }
+func (p pointer) Int32() *int32            { return p.v.Interface().(*int32) }
+func (p pointer) Int32Ptr() **int32        { return p.v.Interface().(**int32) }
+func (p pointer) Int32Slice() *[]int32     { return p.v.Interface().(*[]int32) }
+func (p pointer) Int64() *int64            { return p.v.Interface().(*int64) }
+func (p pointer) Int64Ptr() **int64        { return p.v.Interface().(**int64) }
+func (p pointer) Int64Slice() *[]int64     { return p.v.Interface().(*[]int64) }
+func (p pointer) Uint32() *uint32          { return p.v.Interface().(*uint32) }
+func (p pointer) Uint32Ptr() **uint32      { return p.v.Interface().(**uint32) }
+func (p pointer) Uint32Slice() *[]uint32   { return p.v.Interface().(*[]uint32) }
+func (p pointer) Uint64() *uint64          { return p.v.Interface().(*uint64) }
+func (p pointer) Uint64Ptr() **uint64      { return p.v.Interface().(**uint64) }
+func (p pointer) Uint64Slice() *[]uint64   { return p.v.Interface().(*[]uint64) }
+func (p pointer) Float32() *float32        { return p.v.Interface().(*float32) }
+func (p pointer) Float32Ptr() **float32    { return p.v.Interface().(**float32) }
+func (p pointer) Float32Slice() *[]float32 { return p.v.Interface().(*[]float32) }
+func (p pointer) Float64() *float64        { return p.v.Interface().(*float64) }
+func (p pointer) Float64Ptr() **float64    { return p.v.Interface().(**float64) }
+func (p pointer) Float64Slice() *[]float64 { return p.v.Interface().(*[]float64) }
+func (p pointer) String() *string          { return p.v.Interface().(*string) }
+func (p pointer) StringPtr() **string      { return p.v.Interface().(**string) }
+func (p pointer) StringSlice() *[]string   { return p.v.Interface().(*[]string) }
+func (p pointer) Bytes() *[]byte           { return p.v.Interface().(*[]byte) }
+func (p pointer) BytesSlice() *[][]byte    { return p.v.Interface().(*[][]byte) }
+func (p pointer) WeakFields() *weakFields  { return (*weakFields)(p.v.Interface().(*WeakFields)) }
+func (p pointer) Extensions() *map[int32]ExtensionField {
+	return p.v.Interface().(*map[int32]ExtensionField)
+}
+
+func (p pointer) Elem() pointer {
+	return pointer{v: p.v.Elem()}
+}
+
+// PointerSlice copies []*T from p as a new []pointer.
+// This behavior differs from the implementation in pointer_unsafe.go.
+func (p pointer) PointerSlice() []pointer {
+	// TODO: reconsider this
+	if p.v.IsNil() {
+		return nil
+	}
+	n := p.v.Elem().Len()
+	s := make([]pointer, n)
+	for i := 0; i < n; i++ {
+		s[i] = pointer{v: p.v.Elem().Index(i)}
+	}
+	return s
+}
+
+// AppendPointerSlice appends v to p, which must be a []*T.
+func (p pointer) AppendPointerSlice(v pointer) {
+	sp := p.v.Elem()
+	sp.Set(reflect.Append(sp, v.v))
+}
+
+// SetPointer sets *p to v.
+func (p pointer) SetPointer(v pointer) {
+	p.v.Elem().Set(v.v)
+}
+
+func (Export) MessageStateOf(p Pointer) *messageState     { panic("not supported") }
+func (ms *messageState) pointer() pointer                 { panic("not supported") }
+func (ms *messageState) messageInfo() *MessageInfo        { panic("not supported") }
+func (ms *messageState) LoadMessageInfo() *MessageInfo    { panic("not supported") }
+func (ms *messageState) StoreMessageInfo(mi *MessageInfo) { panic("not supported") }
+
+type atomicNilMessage struct {
+	once sync.Once
+	m    messageReflectWrapper
+}
+
+func (m *atomicNilMessage) Init(mi *MessageInfo) *messageReflectWrapper {
+	m.once.Do(func() {
+		m.m.p = pointerOfIface(reflect.Zero(mi.GoReflectType).Interface())
+		m.m.mi = mi
+	})
+	return &m.m
+}

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

@@ -0,0 +1,173 @@
+// Copyright 2018 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build !purego,!appengine
+
+package impl
+
+import (
+	"reflect"
+	"sync/atomic"
+	"unsafe"
+)
+
+const UnsafeEnabled = true
+
+// Pointer is an opaque pointer type.
+type Pointer unsafe.Pointer
+
+// offset represents the offset to a struct field, accessible from a pointer.
+// The offset is the byte offset to the field from the start of the struct.
+type offset uintptr
+
+// offsetOf returns a field offset for the struct field.
+func offsetOf(f reflect.StructField, x exporter) offset {
+	return offset(f.Offset)
+}
+
+// IsValid reports whether the offset is valid.
+func (f offset) IsValid() bool { return f != invalidOffset }
+
+// invalidOffset is an invalid field offset.
+var invalidOffset = ^offset(0)
+
+// zeroOffset is a noop when calling pointer.Apply.
+var zeroOffset = offset(0)
+
+// pointer is a pointer to a message struct or field.
+type pointer struct{ p unsafe.Pointer }
+
+// pointerOf returns p as a pointer.
+func pointerOf(p Pointer) pointer {
+	return pointer{p: unsafe.Pointer(p)}
+}
+
+// pointerOfValue returns v as a pointer.
+func pointerOfValue(v reflect.Value) pointer {
+	return pointer{p: unsafe.Pointer(v.Pointer())}
+}
+
+// pointerOfIface returns the pointer portion of an interface.
+func pointerOfIface(v interface{}) pointer {
+	type ifaceHeader struct {
+		Type unsafe.Pointer
+		Data unsafe.Pointer
+	}
+	return pointer{p: (*ifaceHeader)(unsafe.Pointer(&v)).Data}
+}
+
+// IsNil reports whether the pointer is nil.
+func (p pointer) IsNil() bool {
+	return p.p == nil
+}
+
+// Apply adds an offset to the pointer to derive a new pointer
+// to a specified field. The pointer must be valid and pointing at a struct.
+func (p pointer) Apply(f offset) pointer {
+	if p.IsNil() {
+		panic("invalid nil pointer")
+	}
+	return pointer{p: unsafe.Pointer(uintptr(p.p) + uintptr(f))}
+}
+
+// AsValueOf treats p as a pointer to an object of type t and returns the value.
+// It is equivalent to reflect.ValueOf(p.AsIfaceOf(t))
+func (p pointer) AsValueOf(t reflect.Type) reflect.Value {
+	return reflect.NewAt(t, p.p)
+}
+
+// AsIfaceOf treats p as a pointer to an object of type t and returns the value.
+// It is equivalent to p.AsValueOf(t).Interface()
+func (p pointer) AsIfaceOf(t reflect.Type) interface{} {
+	// TODO: Use tricky unsafe magic to directly create ifaceHeader.
+	return p.AsValueOf(t).Interface()
+}
+
+func (p pointer) Bool() *bool                           { return (*bool)(p.p) }
+func (p pointer) BoolPtr() **bool                       { return (**bool)(p.p) }
+func (p pointer) BoolSlice() *[]bool                    { return (*[]bool)(p.p) }
+func (p pointer) Int32() *int32                         { return (*int32)(p.p) }
+func (p pointer) Int32Ptr() **int32                     { return (**int32)(p.p) }
+func (p pointer) Int32Slice() *[]int32                  { return (*[]int32)(p.p) }
+func (p pointer) Int64() *int64                         { return (*int64)(p.p) }
+func (p pointer) Int64Ptr() **int64                     { return (**int64)(p.p) }
+func (p pointer) Int64Slice() *[]int64                  { return (*[]int64)(p.p) }
+func (p pointer) Uint32() *uint32                       { return (*uint32)(p.p) }
+func (p pointer) Uint32Ptr() **uint32                   { return (**uint32)(p.p) }
+func (p pointer) Uint32Slice() *[]uint32                { return (*[]uint32)(p.p) }
+func (p pointer) Uint64() *uint64                       { return (*uint64)(p.p) }
+func (p pointer) Uint64Ptr() **uint64                   { return (**uint64)(p.p) }
+func (p pointer) Uint64Slice() *[]uint64                { return (*[]uint64)(p.p) }
+func (p pointer) Float32() *float32                     { return (*float32)(p.p) }
+func (p pointer) Float32Ptr() **float32                 { return (**float32)(p.p) }
+func (p pointer) Float32Slice() *[]float32              { return (*[]float32)(p.p) }
+func (p pointer) Float64() *float64                     { return (*float64)(p.p) }
+func (p pointer) Float64Ptr() **float64                 { return (**float64)(p.p) }
+func (p pointer) Float64Slice() *[]float64              { return (*[]float64)(p.p) }
+func (p pointer) String() *string                       { return (*string)(p.p) }
+func (p pointer) StringPtr() **string                   { return (**string)(p.p) }
+func (p pointer) StringSlice() *[]string                { return (*[]string)(p.p) }
+func (p pointer) Bytes() *[]byte                        { return (*[]byte)(p.p) }
+func (p pointer) BytesSlice() *[][]byte                 { return (*[][]byte)(p.p) }
+func (p pointer) WeakFields() *weakFields               { return (*weakFields)(p.p) }
+func (p pointer) Extensions() *map[int32]ExtensionField { return (*map[int32]ExtensionField)(p.p) }
+
+func (p pointer) Elem() pointer {
+	return pointer{p: *(*unsafe.Pointer)(p.p)}
+}
+
+// PointerSlice loads []*T from p as a []pointer.
+// The value returned is aliased with the original slice.
+// This behavior differs from the implementation in pointer_reflect.go.
+func (p pointer) PointerSlice() []pointer {
+	// Super-tricky - p should point to a []*T where T is a
+	// message type. We load it as []pointer.
+	return *(*[]pointer)(p.p)
+}
+
+// AppendPointerSlice appends v to p, which must be a []*T.
+func (p pointer) AppendPointerSlice(v pointer) {
+	*(*[]pointer)(p.p) = append(*(*[]pointer)(p.p), v)
+}
+
+// SetPointer sets *p to v.
+func (p pointer) SetPointer(v pointer) {
+	*(*unsafe.Pointer)(p.p) = (unsafe.Pointer)(v.p)
+}
+
+// Static check that MessageState does not exceed the size of a pointer.
+const _ = uint(unsafe.Sizeof(unsafe.Pointer(nil)) - unsafe.Sizeof(MessageState{}))
+
+func (Export) MessageStateOf(p Pointer) *messageState {
+	// Super-tricky - see documentation on MessageState.
+	return (*messageState)(unsafe.Pointer(p))
+}
+func (ms *messageState) pointer() pointer {
+	// Super-tricky - see documentation on MessageState.
+	return pointer{p: unsafe.Pointer(ms)}
+}
+func (ms *messageState) messageInfo() *MessageInfo {
+	mi := ms.LoadMessageInfo()
+	if mi == nil {
+		panic("invalid nil message info; this suggests memory corruption due to a race or shallow copy on the message struct")
+	}
+	return mi
+}
+func (ms *messageState) LoadMessageInfo() *MessageInfo {
+	return (*MessageInfo)(atomic.LoadPointer((*unsafe.Pointer)(unsafe.Pointer(&ms.atomicMessageInfo))))
+}
+func (ms *messageState) StoreMessageInfo(mi *MessageInfo) {
+	atomic.StorePointer((*unsafe.Pointer)(unsafe.Pointer(&ms.atomicMessageInfo)), unsafe.Pointer(mi))
+}
+
+type atomicNilMessage struct{ p unsafe.Pointer } // p is a *messageReflectWrapper
+
+func (m *atomicNilMessage) Init(mi *MessageInfo) *messageReflectWrapper {
+	if p := atomic.LoadPointer(&m.p); p != nil {
+		return (*messageReflectWrapper)(p)
+	}
+	w := &messageReflectWrapper{mi: mi}
+	atomic.CompareAndSwapPointer(&m.p, nil, (unsafe.Pointer)(w))
+	return (*messageReflectWrapper)(atomic.LoadPointer(&m.p))
+}

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

@@ -0,0 +1,576 @@
+// Copyright 2019 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package impl
+
+import (
+	"fmt"
+	"math"
+	"math/bits"
+	"reflect"
+	"unicode/utf8"
+
+	"google.golang.org/protobuf/encoding/protowire"
+	"google.golang.org/protobuf/internal/encoding/messageset"
+	"google.golang.org/protobuf/internal/flags"
+	"google.golang.org/protobuf/internal/genid"
+	"google.golang.org/protobuf/internal/strs"
+	pref "google.golang.org/protobuf/reflect/protoreflect"
+	preg "google.golang.org/protobuf/reflect/protoregistry"
+	piface "google.golang.org/protobuf/runtime/protoiface"
+)
+
+// ValidationStatus is the result of validating the wire-format encoding of a message.
+type ValidationStatus int
+
+const (
+	// ValidationUnknown indicates that unmarshaling the message might succeed or fail.
+	// The validator was unable to render a judgement.
+	//
+	// The only causes of this status are an aberrant message type appearing somewhere
+	// in the message or a failure in the extension resolver.
+	ValidationUnknown ValidationStatus = iota + 1
+
+	// ValidationInvalid indicates that unmarshaling the message will fail.
+	ValidationInvalid
+
+	// ValidationValid indicates that unmarshaling the message will succeed.
+	ValidationValid
+)
+
+func (v ValidationStatus) String() string {
+	switch v {
+	case ValidationUnknown:
+		return "ValidationUnknown"
+	case ValidationInvalid:
+		return "ValidationInvalid"
+	case ValidationValid:
+		return "ValidationValid"
+	default:
+		return fmt.Sprintf("ValidationStatus(%d)", int(v))
+	}
+}
+
+// Validate determines whether the contents of the buffer are a valid wire encoding
+// of the message type.
+//
+// This function is exposed for testing.
+func Validate(mt pref.MessageType, in piface.UnmarshalInput) (out piface.UnmarshalOutput, _ ValidationStatus) {
+	mi, ok := mt.(*MessageInfo)
+	if !ok {
+		return out, ValidationUnknown
+	}
+	if in.Resolver == nil {
+		in.Resolver = preg.GlobalTypes
+	}
+	o, st := mi.validate(in.Buf, 0, unmarshalOptions{
+		flags:    in.Flags,
+		resolver: in.Resolver,
+	})
+	if o.initialized {
+		out.Flags |= piface.UnmarshalInitialized
+	}
+	return out, st
+}
+
+type validationInfo struct {
+	mi               *MessageInfo
+	typ              validationType
+	keyType, valType validationType
+
+	// For non-required fields, requiredBit is 0.
+	//
+	// For required fields, requiredBit's nth bit is set, where n is a
+	// unique index in the range [0, MessageInfo.numRequiredFields).
+	//
+	// If there are more than 64 required fields, requiredBit is 0.
+	requiredBit uint64
+}
+
+type validationType uint8
+
+const (
+	validationTypeOther validationType = iota
+	validationTypeMessage
+	validationTypeGroup
+	validationTypeMap
+	validationTypeRepeatedVarint
+	validationTypeRepeatedFixed32
+	validationTypeRepeatedFixed64
+	validationTypeVarint
+	validationTypeFixed32
+	validationTypeFixed64
+	validationTypeBytes
+	validationTypeUTF8String
+	validationTypeMessageSetItem
+)
+
+func newFieldValidationInfo(mi *MessageInfo, si structInfo, fd pref.FieldDescriptor, ft reflect.Type) validationInfo {
+	var vi validationInfo
+	switch {
+	case fd.ContainingOneof() != nil && !fd.ContainingOneof().IsSynthetic():
+		switch fd.Kind() {
+		case pref.MessageKind:
+			vi.typ = validationTypeMessage
+			if ot, ok := si.oneofWrappersByNumber[fd.Number()]; ok {
+				vi.mi = getMessageInfo(ot.Field(0).Type)
+			}
+		case pref.GroupKind:
+			vi.typ = validationTypeGroup
+			if ot, ok := si.oneofWrappersByNumber[fd.Number()]; ok {
+				vi.mi = getMessageInfo(ot.Field(0).Type)
+			}
+		case pref.StringKind:
+			if strs.EnforceUTF8(fd) {
+				vi.typ = validationTypeUTF8String
+			}
+		}
+	default:
+		vi = newValidationInfo(fd, ft)
+	}
+	if fd.Cardinality() == pref.Required {
+		// Avoid overflow. The required field check is done with a 64-bit mask, with
+		// any message containing more than 64 required fields always reported as
+		// potentially uninitialized, so it is not important to get a precise count
+		// of the required fields past 64.
+		if mi.numRequiredFields < math.MaxUint8 {
+			mi.numRequiredFields++
+			vi.requiredBit = 1 << (mi.numRequiredFields - 1)
+		}
+	}
+	return vi
+}
+
+func newValidationInfo(fd pref.FieldDescriptor, ft reflect.Type) validationInfo {
+	var vi validationInfo
+	switch {
+	case fd.IsList():
+		switch fd.Kind() {
+		case pref.MessageKind:
+			vi.typ = validationTypeMessage
+			if ft.Kind() == reflect.Slice {
+				vi.mi = getMessageInfo(ft.Elem())
+			}
+		case pref.GroupKind:
+			vi.typ = validationTypeGroup
+			if ft.Kind() == reflect.Slice {
+				vi.mi = getMessageInfo(ft.Elem())
+			}
+		case pref.StringKind:
+			vi.typ = validationTypeBytes
+			if strs.EnforceUTF8(fd) {
+				vi.typ = validationTypeUTF8String
+			}
+		default:
+			switch wireTypes[fd.Kind()] {
+			case protowire.VarintType:
+				vi.typ = validationTypeRepeatedVarint
+			case protowire.Fixed32Type:
+				vi.typ = validationTypeRepeatedFixed32
+			case protowire.Fixed64Type:
+				vi.typ = validationTypeRepeatedFixed64
+			}
+		}
+	case fd.IsMap():
+		vi.typ = validationTypeMap
+		switch fd.MapKey().Kind() {
+		case pref.StringKind:
+			if strs.EnforceUTF8(fd) {
+				vi.keyType = validationTypeUTF8String
+			}
+		}
+		switch fd.MapValue().Kind() {
+		case pref.MessageKind:
+			vi.valType = validationTypeMessage
+			if ft.Kind() == reflect.Map {
+				vi.mi = getMessageInfo(ft.Elem())
+			}
+		case pref.StringKind:
+			if strs.EnforceUTF8(fd) {
+				vi.valType = validationTypeUTF8String
+			}
+		}
+	default:
+		switch fd.Kind() {
+		case pref.MessageKind:
+			vi.typ = validationTypeMessage
+			if !fd.IsWeak() {
+				vi.mi = getMessageInfo(ft)
+			}
+		case pref.GroupKind:
+			vi.typ = validationTypeGroup
+			vi.mi = getMessageInfo(ft)
+		case pref.StringKind:
+			vi.typ = validationTypeBytes
+			if strs.EnforceUTF8(fd) {
+				vi.typ = validationTypeUTF8String
+			}
+		default:
+			switch wireTypes[fd.Kind()] {
+			case protowire.VarintType:
+				vi.typ = validationTypeVarint
+			case protowire.Fixed32Type:
+				vi.typ = validationTypeFixed32
+			case protowire.Fixed64Type:
+				vi.typ = validationTypeFixed64
+			case protowire.BytesType:
+				vi.typ = validationTypeBytes
+			}
+		}
+	}
+	return vi
+}
+
+func (mi *MessageInfo) validate(b []byte, groupTag protowire.Number, opts unmarshalOptions) (out unmarshalOutput, result ValidationStatus) {
+	mi.init()
+	type validationState struct {
+		typ              validationType
+		keyType, valType validationType
+		endGroup         protowire.Number
+		mi               *MessageInfo
+		tail             []byte
+		requiredMask     uint64
+	}
+
+	// Pre-allocate some slots to avoid repeated slice reallocation.
+	states := make([]validationState, 0, 16)
+	states = append(states, validationState{
+		typ: validationTypeMessage,
+		mi:  mi,
+	})
+	if groupTag > 0 {
+		states[0].typ = validationTypeGroup
+		states[0].endGroup = groupTag
+	}
+	initialized := true
+	start := len(b)
+State:
+	for len(states) > 0 {
+		st := &states[len(states)-1]
+		for len(b) > 0 {
+			// Parse the tag (field number and wire type).
+			var tag uint64
+			if b[0] < 0x80 {
+				tag = uint64(b[0])
+				b = b[1:]
+			} else if len(b) >= 2 && b[1] < 128 {
+				tag = uint64(b[0]&0x7f) + uint64(b[1])<<7
+				b = b[2:]
+			} else {
+				var n int
+				tag, n = protowire.ConsumeVarint(b)
+				if n < 0 {
+					return out, ValidationInvalid
+				}
+				b = b[n:]
+			}
+			var num protowire.Number
+			if n := tag >> 3; n < uint64(protowire.MinValidNumber) || n > uint64(protowire.MaxValidNumber) {
+				return out, ValidationInvalid
+			} else {
+				num = protowire.Number(n)
+			}
+			wtyp := protowire.Type(tag & 7)
+
+			if wtyp == protowire.EndGroupType {
+				if st.endGroup == num {
+					goto PopState
+				}
+				return out, ValidationInvalid
+			}
+			var vi validationInfo
+			switch {
+			case st.typ == validationTypeMap:
+				switch num {
+				case genid.MapEntry_Key_field_number:
+					vi.typ = st.keyType
+				case genid.MapEntry_Value_field_number:
+					vi.typ = st.valType
+					vi.mi = st.mi
+					vi.requiredBit = 1
+				}
+			case flags.ProtoLegacy && st.mi.isMessageSet:
+				switch num {
+				case messageset.FieldItem:
+					vi.typ = validationTypeMessageSetItem
+				}
+			default:
+				var f *coderFieldInfo
+				if int(num) < len(st.mi.denseCoderFields) {
+					f = st.mi.denseCoderFields[num]
+				} else {
+					f = st.mi.coderFields[num]
+				}
+				if f != nil {
+					vi = f.validation
+					if vi.typ == validationTypeMessage && vi.mi == nil {
+						// Probable weak field.
+						//
+						// TODO: Consider storing the results of this lookup somewhere
+						// rather than recomputing it on every validation.
+						fd := st.mi.Desc.Fields().ByNumber(num)
+						if fd == nil || !fd.IsWeak() {
+							break
+						}
+						messageName := fd.Message().FullName()
+						messageType, err := preg.GlobalTypes.FindMessageByName(messageName)
+						switch err {
+						case nil:
+							vi.mi, _ = messageType.(*MessageInfo)
+						case preg.NotFound:
+							vi.typ = validationTypeBytes
+						default:
+							return out, ValidationUnknown
+						}
+					}
+					break
+				}
+				// Possible extension field.
+				//
+				// TODO: We should return ValidationUnknown when:
+				//   1. The resolver is not frozen. (More extensions may be added to it.)
+				//   2. The resolver returns preg.NotFound.
+				// In this case, a type added to the resolver in the future could cause
+				// unmarshaling to begin failing. Supporting this requires some way to
+				// determine if the resolver is frozen.
+				xt, err := opts.resolver.FindExtensionByNumber(st.mi.Desc.FullName(), num)
+				if err != nil && err != preg.NotFound {
+					return out, ValidationUnknown
+				}
+				if err == nil {
+					vi = getExtensionFieldInfo(xt).validation
+				}
+			}
+			if vi.requiredBit != 0 {
+				// Check that the field has a compatible wire type.
+				// We only need to consider non-repeated field types,
+				// since repeated fields (and maps) can never be required.
+				ok := false
+				switch vi.typ {
+				case validationTypeVarint:
+					ok = wtyp == protowire.VarintType
+				case validationTypeFixed32:
+					ok = wtyp == protowire.Fixed32Type
+				case validationTypeFixed64:
+					ok = wtyp == protowire.Fixed64Type
+				case validationTypeBytes, validationTypeUTF8String, validationTypeMessage:
+					ok = wtyp == protowire.BytesType
+				case validationTypeGroup:
+					ok = wtyp == protowire.StartGroupType
+				}
+				if ok {
+					st.requiredMask |= vi.requiredBit
+				}
+			}
+
+			switch wtyp {
+			case protowire.VarintType:
+				if len(b) >= 10 {
+					switch {
+					case b[0] < 0x80:
+						b = b[1:]
+					case b[1] < 0x80:
+						b = b[2:]
+					case b[2] < 0x80:
+						b = b[3:]
+					case b[3] < 0x80:
+						b = b[4:]
+					case b[4] < 0x80:
+						b = b[5:]
+					case b[5] < 0x80:
+						b = b[6:]
+					case b[6] < 0x80:
+						b = b[7:]
+					case b[7] < 0x80:
+						b = b[8:]
+					case b[8] < 0x80:
+						b = b[9:]
+					case b[9] < 0x80 && b[9] < 2:
+						b = b[10:]
+					default:
+						return out, ValidationInvalid
+					}
+				} else {
+					switch {
+					case len(b) > 0 && b[0] < 0x80:
+						b = b[1:]
+					case len(b) > 1 && b[1] < 0x80:
+						b = b[2:]
+					case len(b) > 2 && b[2] < 0x80:
+						b = b[3:]
+					case len(b) > 3 && b[3] < 0x80:
+						b = b[4:]
+					case len(b) > 4 && b[4] < 0x80:
+						b = b[5:]
+					case len(b) > 5 && b[5] < 0x80:
+						b = b[6:]
+					case len(b) > 6 && b[6] < 0x80:
+						b = b[7:]
+					case len(b) > 7 && b[7] < 0x80:
+						b = b[8:]
+					case len(b) > 8 && b[8] < 0x80:
+						b = b[9:]
+					case len(b) > 9 && b[9] < 2:
+						b = b[10:]
+					default:
+						return out, ValidationInvalid
+					}
+				}
+				continue State
+			case protowire.BytesType:
+				var size uint64
+				if len(b) >= 1 && b[0] < 0x80 {
+					size = uint64(b[0])
+					b = b[1:]
+				} else if len(b) >= 2 && b[1] < 128 {
+					size = uint64(b[0]&0x7f) + uint64(b[1])<<7
+					b = b[2:]
+				} else {
+					var n int
+					size, n = protowire.ConsumeVarint(b)
+					if n < 0 {
+						return out, ValidationInvalid
+					}
+					b = b[n:]
+				}
+				if size > uint64(len(b)) {
+					return out, ValidationInvalid
+				}
+				v := b[:size]
+				b = b[size:]
+				switch vi.typ {
+				case validationTypeMessage:
+					if vi.mi == nil {
+						return out, ValidationUnknown
+					}
+					vi.mi.init()
+					fallthrough
+				case validationTypeMap:
+					if vi.mi != nil {
+						vi.mi.init()
+					}
+					states = append(states, validationState{
+						typ:     vi.typ,
+						keyType: vi.keyType,
+						valType: vi.valType,
+						mi:      vi.mi,
+						tail:    b,
+					})
+					b = v
+					continue State
+				case validationTypeRepeatedVarint:
+					// Packed field.
+					for len(v) > 0 {
+						_, n := protowire.ConsumeVarint(v)
+						if n < 0 {
+							return out, ValidationInvalid
+						}
+						v = v[n:]
+					}
+				case validationTypeRepeatedFixed32:
+					// Packed field.
+					if len(v)%4 != 0 {
+						return out, ValidationInvalid
+					}
+				case validationTypeRepeatedFixed64:
+					// Packed field.
+					if len(v)%8 != 0 {
+						return out, ValidationInvalid
+					}
+				case validationTypeUTF8String:
+					if !utf8.Valid(v) {
+						return out, ValidationInvalid
+					}
+				}
+			case protowire.Fixed32Type:
+				if len(b) < 4 {
+					return out, ValidationInvalid
+				}
+				b = b[4:]
+			case protowire.Fixed64Type:
+				if len(b) < 8 {
+					return out, ValidationInvalid
+				}
+				b = b[8:]
+			case protowire.StartGroupType:
+				switch {
+				case vi.typ == validationTypeGroup:
+					if vi.mi == nil {
+						return out, ValidationUnknown
+					}
+					vi.mi.init()
+					states = append(states, validationState{
+						typ:      validationTypeGroup,
+						mi:       vi.mi,
+						endGroup: num,
+					})
+					continue State
+				case flags.ProtoLegacy && vi.typ == validationTypeMessageSetItem:
+					typeid, v, n, err := messageset.ConsumeFieldValue(b, false)
+					if err != nil {
+						return out, ValidationInvalid
+					}
+					xt, err := opts.resolver.FindExtensionByNumber(st.mi.Desc.FullName(), typeid)
+					switch {
+					case err == preg.NotFound:
+						b = b[n:]
+					case err != nil:
+						return out, ValidationUnknown
+					default:
+						xvi := getExtensionFieldInfo(xt).validation
+						if xvi.mi != nil {
+							xvi.mi.init()
+						}
+						states = append(states, validationState{
+							typ:  xvi.typ,
+							mi:   xvi.mi,
+							tail: b[n:],
+						})
+						b = v
+						continue State
+					}
+				default:
+					n := protowire.ConsumeFieldValue(num, wtyp, b)
+					if n < 0 {
+						return out, ValidationInvalid
+					}
+					b = b[n:]
+				}
+			default:
+				return out, ValidationInvalid
+			}
+		}
+		if st.endGroup != 0 {
+			return out, ValidationInvalid
+		}
+		if len(b) != 0 {
+			return out, ValidationInvalid
+		}
+		b = st.tail
+	PopState:
+		numRequiredFields := 0
+		switch st.typ {
+		case validationTypeMessage, validationTypeGroup:
+			numRequiredFields = int(st.mi.numRequiredFields)
+		case validationTypeMap:
+			// If this is a map field with a message value that contains
+			// required fields, require that the value be present.
+			if st.mi != nil && st.mi.numRequiredFields > 0 {
+				numRequiredFields = 1
+			}
+		}
+		// If there are more than 64 required fields, this check will
+		// always fail and we will report that the message is potentially
+		// uninitialized.
+		if numRequiredFields > 0 && bits.OnesCount64(st.requiredMask) != numRequiredFields {
+			initialized = false
+		}
+		states = states[:len(states)-1]
+	}
+	out.n = start - len(b)
+	if initialized {
+		out.initialized = true
+	}
+	return out, ValidationValid
+}

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

@@ -0,0 +1,74 @@
+// Copyright 2019 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package impl
+
+import (
+	"fmt"
+
+	pref "google.golang.org/protobuf/reflect/protoreflect"
+	"google.golang.org/protobuf/reflect/protoregistry"
+)
+
+// weakFields adds methods to the exported WeakFields type for internal use.
+//
+// The exported type is an alias to an unnamed type, so methods can't be
+// defined directly on it.
+type weakFields WeakFields
+
+func (w weakFields) get(num pref.FieldNumber) (pref.ProtoMessage, bool) {
+	m, ok := w[int32(num)]
+	return m, ok
+}
+
+func (w *weakFields) set(num pref.FieldNumber, m pref.ProtoMessage) {
+	if *w == nil {
+		*w = make(weakFields)
+	}
+	(*w)[int32(num)] = m
+}
+
+func (w *weakFields) clear(num pref.FieldNumber) {
+	delete(*w, int32(num))
+}
+
+func (Export) HasWeak(w WeakFields, num pref.FieldNumber) bool {
+	_, ok := w[int32(num)]
+	return ok
+}
+
+func (Export) ClearWeak(w *WeakFields, num pref.FieldNumber) {
+	delete(*w, int32(num))
+}
+
+func (Export) GetWeak(w WeakFields, num pref.FieldNumber, name pref.FullName) pref.ProtoMessage {
+	if m, ok := w[int32(num)]; ok {
+		return m
+	}
+	mt, _ := protoregistry.GlobalTypes.FindMessageByName(name)
+	if mt == nil {
+		panic(fmt.Sprintf("message %v for weak field is not linked in", name))
+	}
+	return mt.Zero().Interface()
+}
+
+func (Export) SetWeak(w *WeakFields, num pref.FieldNumber, name pref.FullName, m pref.ProtoMessage) {
+	if m != nil {
+		mt, _ := protoregistry.GlobalTypes.FindMessageByName(name)
+		if mt == nil {
+			panic(fmt.Sprintf("message %v for weak field is not linked in", name))
+		}
+		if mt != m.ProtoReflect().Type() {
+			panic(fmt.Sprintf("invalid message type for weak field: got %T, want %T", m, mt.Zero().Interface()))
+		}
+	}
+	if m == nil || !m.ProtoReflect().IsValid() {
+		delete(*w, int32(num))
+		return
+	}
+	if *w == nil {
+		*w = make(weakFields)
+	}
+	(*w)[int32(num)] = m
+}