1 files changed, 364 insertions, 0 deletions
diff --git a/vendor/google.golang.org/protobuf/internal/impl/message_reflect.go b/vendor/google.golang.org/protobuf/internal/impl/message_reflect.go
new file mode 100644
index 000000000..0f4b8db76
--- /dev/null
+++ b/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()))
+}