gtsocial-umbx

desc_resolve.go (10131B)

---

 // 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 protodesc
 
 import (
 	"google.golang.org/protobuf/internal/encoding/defval"
 	"google.golang.org/protobuf/internal/errors"
 	"google.golang.org/protobuf/internal/filedesc"
 	"google.golang.org/protobuf/reflect/protoreflect"
 	"google.golang.org/protobuf/reflect/protoregistry"
 
 	"google.golang.org/protobuf/types/descriptorpb"
 )
 
 // resolver is a wrapper around a local registry of declarations within the file
 // and the remote resolver. The remote resolver is restricted to only return
 // descriptors that have been imported.
 type resolver struct {
 	local   descsByName
 	remote  Resolver
 	imports importSet
 
 	allowUnresolvable bool
 }
 
 func (r *resolver) resolveMessageDependencies(ms []filedesc.Message, mds []*descriptorpb.DescriptorProto) (err error) {
 	for i, md := range mds {
 		m := &ms[i]
 		for j, fd := range md.GetField() {
 			f := &m.L2.Fields.List[j]
 			if f.L1.Cardinality == protoreflect.Required {
 				m.L2.RequiredNumbers.List = append(m.L2.RequiredNumbers.List, f.L1.Number)
 			}
 			if fd.OneofIndex != nil {
 				k := int(fd.GetOneofIndex())
 				if !(0 <= k && k < len(md.GetOneofDecl())) {
 					return errors.New("message field %q has an invalid oneof index: %d", f.FullName(), k)
 				}
 				o := &m.L2.Oneofs.List[k]
 				f.L1.ContainingOneof = o
 				o.L1.Fields.List = append(o.L1.Fields.List, f)
 			}
 
 			if f.L1.Kind, f.L1.Enum, f.L1.Message, err = r.findTarget(f.Kind(), f.Parent().FullName(), partialName(fd.GetTypeName()), f.IsWeak()); err != nil {
 				return errors.New("message field %q cannot resolve type: %v", f.FullName(), err)
 			}
 			if fd.DefaultValue != nil {
 				v, ev, err := unmarshalDefault(fd.GetDefaultValue(), f, r.allowUnresolvable)
 				if err != nil {
 					return errors.New("message field %q has invalid default: %v", f.FullName(), err)
 				}
 				f.L1.Default = filedesc.DefaultValue(v, ev)
 			}
 		}
 
 		if err := r.resolveMessageDependencies(m.L1.Messages.List, md.GetNestedType()); err != nil {
 			return err
 		}
 		if err := r.resolveExtensionDependencies(m.L1.Extensions.List, md.GetExtension()); err != nil {
 			return err
 		}
 	}
 	return nil
 }
 
 func (r *resolver) resolveExtensionDependencies(xs []filedesc.Extension, xds []*descriptorpb.FieldDescriptorProto) (err error) {
 	for i, xd := range xds {
 		x := &xs[i]
 		if x.L1.Extendee, err = r.findMessageDescriptor(x.Parent().FullName(), partialName(xd.GetExtendee()), false); err != nil {
 			return errors.New("extension field %q cannot resolve extendee: %v", x.FullName(), err)
 		}
 		if x.L1.Kind, x.L2.Enum, x.L2.Message, err = r.findTarget(x.Kind(), x.Parent().FullName(), partialName(xd.GetTypeName()), false); err != nil {
 			return errors.New("extension field %q cannot resolve type: %v", x.FullName(), err)
 		}
 		if xd.DefaultValue != nil {
 			v, ev, err := unmarshalDefault(xd.GetDefaultValue(), x, r.allowUnresolvable)
 			if err != nil {
 				return errors.New("extension field %q has invalid default: %v", x.FullName(), err)
 			}
 			x.L2.Default = filedesc.DefaultValue(v, ev)
 		}
 	}
 	return nil
 }
 
 func (r *resolver) resolveServiceDependencies(ss []filedesc.Service, sds []*descriptorpb.ServiceDescriptorProto) (err error) {
 	for i, sd := range sds {
 		s := &ss[i]
 		for j, md := range sd.GetMethod() {
 			m := &s.L2.Methods.List[j]
 			m.L1.Input, err = r.findMessageDescriptor(m.Parent().FullName(), partialName(md.GetInputType()), false)
 			if err != nil {
 				return errors.New("service method %q cannot resolve input: %v", m.FullName(), err)
 			}
 			m.L1.Output, err = r.findMessageDescriptor(s.FullName(), partialName(md.GetOutputType()), false)
 			if err != nil {
 				return errors.New("service method %q cannot resolve output: %v", m.FullName(), err)
 			}
 		}
 	}
 	return nil
 }
 
 // findTarget finds an enum or message descriptor if k is an enum, message,
 // group, or unknown. If unknown, and the name could be resolved, the kind
 // returned kind is set based on the type of the resolved descriptor.
 func (r *resolver) findTarget(k protoreflect.Kind, scope protoreflect.FullName, ref partialName, isWeak bool) (protoreflect.Kind, protoreflect.EnumDescriptor, protoreflect.MessageDescriptor, error) {
 	switch k {
 	case protoreflect.EnumKind:
 		ed, err := r.findEnumDescriptor(scope, ref, isWeak)
 		if err != nil {
 			return 0, nil, nil, err
 		}
 		return k, ed, nil, nil
 	case protoreflect.MessageKind, protoreflect.GroupKind:
 		md, err := r.findMessageDescriptor(scope, ref, isWeak)
 		if err != nil {
 			return 0, nil, nil, err
 		}
 		return k, nil, md, nil
 	case 0:
 		// Handle unspecified kinds (possible with parsers that operate
 		// on a per-file basis without knowledge of dependencies).
 		d, err := r.findDescriptor(scope, ref)
 		if err == protoregistry.NotFound && (r.allowUnresolvable || isWeak) {
 			return k, filedesc.PlaceholderEnum(ref.FullName()), filedesc.PlaceholderMessage(ref.FullName()), nil
 		} else if err == protoregistry.NotFound {
 			return 0, nil, nil, errors.New("%q not found", ref.FullName())
 		} else if err != nil {
 			return 0, nil, nil, err
 		}
 		switch d := d.(type) {
 		case protoreflect.EnumDescriptor:
 			return protoreflect.EnumKind, d, nil, nil
 		case protoreflect.MessageDescriptor:
 			return protoreflect.MessageKind, nil, d, nil
 		default:
 			return 0, nil, nil, errors.New("unknown kind")
 		}
 	default:
 		if ref != "" {
 			return 0, nil, nil, errors.New("target name cannot be specified for %v", k)
 		}
 		if !k.IsValid() {
 			return 0, nil, nil, errors.New("invalid kind: %d", k)
 		}
 		return k, nil, nil, nil
 	}
 }
 
 // findDescriptor finds the descriptor by name,
 // which may be a relative name within some scope.
 //
 // Suppose the scope was "fizz.buzz" and the reference was "Foo.Bar",
 // then the following full names are searched:
 //   - fizz.buzz.Foo.Bar
 //   - fizz.Foo.Bar
 //   - Foo.Bar
 func (r *resolver) findDescriptor(scope protoreflect.FullName, ref partialName) (protoreflect.Descriptor, error) {
 	if !ref.IsValid() {
 		return nil, errors.New("invalid name reference: %q", ref)
 	}
 	if ref.IsFull() {
 		scope, ref = "", ref[1:]
 	}
 	var foundButNotImported protoreflect.Descriptor
 	for {
 		// Derive the full name to search.
 		s := protoreflect.FullName(ref)
 		if scope != "" {
 			s = scope + "." + s
 		}
 
 		// Check the current file for the descriptor.
 		if d, ok := r.local[s]; ok {
 			return d, nil
 		}
 
 		// Check the remote registry for the descriptor.
 		d, err := r.remote.FindDescriptorByName(s)
 		if err == nil {
 			// Only allow descriptors covered by one of the imports.
 			if r.imports[d.ParentFile().Path()] {
 				return d, nil
 			}
 			foundButNotImported = d
 		} else if err != protoregistry.NotFound {
 			return nil, errors.Wrap(err, "%q", s)
 		}
 
 		// Continue on at a higher level of scoping.
 		if scope == "" {
 			if d := foundButNotImported; d != nil {
 				return nil, errors.New("resolved %q, but %q is not imported", d.FullName(), d.ParentFile().Path())
 			}
 			return nil, protoregistry.NotFound
 		}
 		scope = scope.Parent()
 	}
 }
 
 func (r *resolver) findEnumDescriptor(scope protoreflect.FullName, ref partialName, isWeak bool) (protoreflect.EnumDescriptor, error) {
 	d, err := r.findDescriptor(scope, ref)
 	if err == protoregistry.NotFound && (r.allowUnresolvable || isWeak) {
 		return filedesc.PlaceholderEnum(ref.FullName()), nil
 	} else if err == protoregistry.NotFound {
 		return nil, errors.New("%q not found", ref.FullName())
 	} else if err != nil {
 		return nil, err
 	}
 	ed, ok := d.(protoreflect.EnumDescriptor)
 	if !ok {
 		return nil, errors.New("resolved %q, but it is not an enum", d.FullName())
 	}
 	return ed, nil
 }
 
 func (r *resolver) findMessageDescriptor(scope protoreflect.FullName, ref partialName, isWeak bool) (protoreflect.MessageDescriptor, error) {
 	d, err := r.findDescriptor(scope, ref)
 	if err == protoregistry.NotFound && (r.allowUnresolvable || isWeak) {
 		return filedesc.PlaceholderMessage(ref.FullName()), nil
 	} else if err == protoregistry.NotFound {
 		return nil, errors.New("%q not found", ref.FullName())
 	} else if err != nil {
 		return nil, err
 	}
 	md, ok := d.(protoreflect.MessageDescriptor)
 	if !ok {
 		return nil, errors.New("resolved %q, but it is not an message", d.FullName())
 	}
 	return md, nil
 }
 
 // partialName is the partial name. A leading dot means that the name is full,
 // otherwise the name is relative to some current scope.
 // See google.protobuf.FieldDescriptorProto.type_name.
 type partialName string
 
 func (s partialName) IsFull() bool {
 	return len(s) > 0 && s[0] == '.'
 }
 
 func (s partialName) IsValid() bool {
 	if s.IsFull() {
 		return protoreflect.FullName(s[1:]).IsValid()
 	}
 	return protoreflect.FullName(s).IsValid()
 }
 
 const unknownPrefix = "*."
 
 // FullName converts the partial name to a full name on a best-effort basis.
 // If relative, it creates an invalid full name, using a "*." prefix
 // to indicate that the start of the full name is unknown.
 func (s partialName) FullName() protoreflect.FullName {
 	if s.IsFull() {
 		return protoreflect.FullName(s[1:])
 	}
 	return protoreflect.FullName(unknownPrefix + s)
 }
 
 func unmarshalDefault(s string, fd protoreflect.FieldDescriptor, allowUnresolvable bool) (protoreflect.Value, protoreflect.EnumValueDescriptor, error) {
 	var evs protoreflect.EnumValueDescriptors
 	if fd.Enum() != nil {
 		evs = fd.Enum().Values()
 	}
 	v, ev, err := defval.Unmarshal(s, fd.Kind(), evs, defval.Descriptor)
 	if err != nil && allowUnresolvable && evs != nil && protoreflect.Name(s).IsValid() {
 		v = protoreflect.ValueOfEnum(0)
 		if evs.Len() > 0 {
 			v = protoreflect.ValueOfEnum(evs.Get(0).Number())
 		}
 		ev = filedesc.PlaceholderEnumValue(fd.Enum().FullName().Parent().Append(protoreflect.Name(s)))
 	} else if err != nil {
 		return v, ev, err
 	}
 	if fd.Syntax() == protoreflect.Proto3 {
 		return v, ev, errors.New("cannot be specified under proto3 semantics")
 	}
 	if fd.Kind() == protoreflect.MessageKind || fd.Kind() == protoreflect.GroupKind || fd.Cardinality() == protoreflect.Repeated {
 		return v, ev, errors.New("cannot be specified on composite types")
 	}
 	return v, ev, nil
 }