support editions in desc/builder package (#605)

desc/builder/builder_test.go

@@ -342,10 +342,17 @@ func TestProto3Optional(t *testing.T) {
 }
 
 func TestBuildersFromDescriptors(t *testing.T) {
-	for _, s := range []string{"desc_test1.proto", "desc_test2.proto", "desc_test_defaults.proto", "desc_test_options.proto", "desc_test_proto3.proto", "desc_test_wellknowntypes.proto", "nopkg/desc_test_nopkg.proto", "nopkg/desc_test_nopkg_new.proto", "pkg/desc_test_pkg.proto"} {
-		fd, err := desc.LoadFileDescriptor(s)
-		testutil.Ok(t, err)
-		roundTripFile(t, fd)
+	for _, s := range []string{
+		"desc_test1.proto", "desc_test2.proto",
+		"desc_test_defaults.proto", "desc_test_editions.proto", "desc_test_options.proto",
+		"desc_test_proto3.proto", "desc_test_wellknowntypes.proto",
+		"nopkg/desc_test_nopkg.proto", "nopkg/desc_test_nopkg_new.proto", "pkg/desc_test_pkg.proto",
+	} {
+		t.Run(s, func(t *testing.T) {
+			fd, err := desc.LoadFileDescriptor(s)
+			testutil.Ok(t, err)
+			roundTripFile(t, fd)
+		})
 	}
 }
 
@@ -1641,7 +1648,7 @@ func TestInvalid(t *testing.T) {
 						NewMessage("Foo").AddField(NewField("foo", FieldTypeBool()).SetRequired()),
 					)
 			},
-			expectedError: "proto3 does not allow required fields",
+			expectedError: "only proto2 allows required fields",
 		},
 		{
 			name: "extension range in proto3",

desc/builder/field.go

@@ -32,11 +32,23 @@ type FieldBuilder struct {
 	msgType   *MessageBuilder
 	fieldType *FieldType
 
-	Options        *descriptorpb.FieldOptions
-	Label          descriptorpb.FieldDescriptorProto_Label
+	Options *descriptorpb.FieldOptions
+	Label   descriptorpb.FieldDescriptorProto_Label
+
+	// Proto3Optional indicates if the field is a proto3 optional field. This
+	// only applies to fields in files with "proto3" syntax whose Cardinality
+	// is set to protoreflect.Optional.
+	//
+	// If the file's syntax is not "proto3", this may not be set to true.
+	//
+	// This allows setting a field in a proto3 file to have explicit field
+	// presence. To manage field presence for fields in files that use
+	// "editions", set the field_presence field of the features option in
+	// Options.
 	Proto3Optional bool
-	Default        string
-	JsonName       string
+
+	Default  string
+	JsonName string
 
 	foreignExtendee *desc.MessageDescriptor
 	localExtendee   *MessageBuilder
@@ -496,6 +508,7 @@ func (flb *FieldBuilder) buildProto(path []int32, sourceInfo *descriptorpb.Sourc
 	addCommentsTo(sourceInfo, path, &flb.comments)
 
 	isProto3 := flb.GetFile().IsProto3
+	isEditions := flb.GetFile().Edition > 0
 	if flb.Proto3Optional {
 		if !isProto3 {
 			return nil, fmt.Errorf("field %s is not in a proto3 syntax file but is marked as a proto3 optional field", GetFullyQualifiedName(flb))
@@ -510,8 +523,8 @@ func (flb *FieldBuilder) buildProto(path []int32, sourceInfo *descriptorpb.Sourc
 
 	var lbl *descriptorpb.FieldDescriptorProto_Label
 	if int32(flb.Label) != 0 {
-		if isProto3 && flb.Label == descriptorpb.FieldDescriptorProto_LABEL_REQUIRED {
-			return nil, fmt.Errorf("field %s: proto3 does not allow required fields", GetFullyQualifiedName(flb))
+		if (isProto3 || isEditions) && flb.Label == descriptorpb.FieldDescriptorProto_LABEL_REQUIRED {
+			return nil, fmt.Errorf("field %s: only proto2 allows required fields", GetFullyQualifiedName(flb))
 		}
 		lbl = flb.Label.Enum()
 	}

desc/builder/file.go

@@ -46,9 +46,17 @@ func makeUnique(name string, existingNames map[string]struct{}) string {
 type FileBuilder struct {
 	name string
 
+	// IsProto3 indicates that the file's syntax is "proto3". If this is
+	// false the file either uses syntax "proto2" (when Edition is zero)
+	// or uses editions (when Edition is non-zero).
 	IsProto3 bool
-	Package  string
-	Options  *descriptorpb.FileOptions
+
+	// Edition indicates which edition this file uses. It may only be
+	// set when IsProto3 is false.
+	Edition descriptorpb.Edition
+
+	Package string
+	Options *descriptorpb.FileOptions
 
 	comments        Comments
 	SyntaxComments  Comments
@@ -82,14 +90,15 @@ func NewFile(name string) *FileBuilder {
 func FromFile(fd *desc.FileDescriptor) (*FileBuilder, error) {
 	fb := NewFile(fd.GetName())
 	fb.IsProto3 = fd.IsProto3()
+	fb.Edition = fd.Edition()
 	fb.Package = fd.GetPackage()
 	fb.Options = fd.GetFileOptions()
 	setComments(&fb.comments, fd.GetSourceInfo())
 
 	// find syntax and package comments, too
 	for _, loc := range fd.AsFileDescriptorProto().GetSourceCodeInfo().GetLocation() {
 		if len(loc.Path) == 1 {
-			if loc.Path[0] == internal.File_syntaxTag {
+			if loc.Path[0] == internal.File_syntaxTag || loc.Path[0] == internal.File_editionTag {
 				setComments(&fb.SyntaxComments, loc)
 			} else if loc.Path[0] == internal.File_packageTag {
 				setComments(&fb.PackageComments, loc)
@@ -649,9 +658,31 @@ func (fb *FileBuilder) SetPackageName(pkg string) *FileBuilder {
 }
 
 // SetProto3 sets whether this file is declared to use "proto3" syntax or not
-// and returns the file, for method chaining.
+// and returns the file, for method chaining. If this is called with a value
+// of false, then "proto2" syntax is assumed. To instead set the file to use
+// editions, call SetEdition.
 func (fb *FileBuilder) SetProto3(isProto3 bool) *FileBuilder {
 	fb.IsProto3 = isProto3
+	fb.Edition = 0
+	return fb
+}
+
+// SetEdition sets the edition that this file uses and returns the file, for
+// method chaining. This supports the use of the EDITION_PROTO2 and EDITION_PROTO3
+// values to actually set the value as "proto2" or "proto3" syntax respectively.
+// If a value less than EDITION_PROTO2 is provided, the invalid value is ignored
+// and the file is instead set to use "proto2" syntax.
+func (fb *FileBuilder) SetEdition(edition descriptorpb.Edition) *FileBuilder {
+	if edition <= descriptorpb.Edition_EDITION_PROTO2 {
+		fb.IsProto3 = false
+		fb.Edition = 0
+	} else if edition == descriptorpb.Edition_EDITION_PROTO3 {
+		fb.IsProto3 = true
+		fb.Edition = 0
+	} else {
+		fb.IsProto3 = false
+		fb.Edition = edition
+	}
 	return fb
 }
 
@@ -661,8 +692,19 @@ func (fb *FileBuilder) buildProto(deps []*desc.FileDescriptor) (*descriptorpb.Fi
 		name = uniqueFileName()
 	}
 	var syntax *string
+	var edition *descriptorpb.Edition
 	if fb.IsProto3 {
 		syntax = proto.String("proto3")
+	} else if fb.Edition > 0 {
+		if fb.Edition < descriptorpb.Edition_EDITION_2023 ||
+			fb.Edition >= descriptorpb.Edition_EDITION_MAX ||
+			descriptorpb.Edition_name[int32(fb.Edition)] == "" ||
+			strings.HasSuffix(fb.Edition.String(), "_TEST_ONLY") {
+			// Not a valid edition!
+			return nil, fmt.Errorf("builder contains unknown or invalid edition: %v", fb.Edition)
+		}
+		syntax = proto.String("editions")
+		edition = fb.Edition.Enum()
 	}
 	var pkg *string
 	if fb.Package != "" {
@@ -727,6 +769,7 @@ func (fb *FileBuilder) buildProto(deps []*desc.FileDescriptor) (*descriptorpb.Fi
 		Dependency:     imports,
 		Options:        fb.Options,
 		Syntax:         syntax,
+		Edition:        edition,
 		MessageType:    messages,
 		EnumType:       enums,
 		Extension:      extensions,

desc/descriptor.go

@@ -155,10 +155,22 @@ func (fd *FileDescriptor) String() string {
 }
 
 // IsProto3 returns true if the file declares a syntax of "proto3".
+//
+// When this returns false, the file is either syntax "proto2" (if
+// Edition() returns zero) or the file uses editions.
 func (fd *FileDescriptor) IsProto3() bool {
 	return fd.wrapped.Syntax() == protoreflect.Proto3
 }
 
+// Edition returns the edition of the file. If the file does not
+// use editions syntax, zero is returned.
+func (fd *FileDescriptor) Edition() descriptorpb.Edition {
+	if fd.wrapped.Syntax() == protoreflect.Editions {
+		return fd.proto.GetEdition()
+	}
+	return 0
+}
+
 // GetDependencies returns all of this file's dependencies. These correspond to
 // import statements in the file.
 func (fd *FileDescriptor) GetDependencies() []*FileDescriptor {

desc/internal/util.go

@@ -54,6 +54,9 @@ const (
 	// File_syntaxTag is the tag number of the syntax element in a file
 	// descriptor proto.
 	File_syntaxTag = 12
+	// File_editionTag is the tag number of the edition element in a file
+	// descriptor proto.
+	File_editionTag = 14
 	// Message_nameTag is the tag number of the name element in a message
 	// descriptor proto.
 	Message_nameTag = 1

desc/sourceinfo/wrappers.go

@@ -2,7 +2,6 @@ package sourceinfo
 
 import (
 	"fmt"
-
 	"google.golang.org/protobuf/reflect/protoreflect"
 )
 
@@ -16,6 +15,14 @@ type fileDescriptor struct {
 	locs protoreflect.SourceLocations
 }
 
+func (f fileDescriptor) Edition() int32 {
+	ed, ok := f.FileDescriptor.(interface{ Edition() int32 })
+	if ok {
+		return ed.Edition()
+	}
+	return 0
+}
+
 func (f fileDescriptor) ParentFile() protoreflect.FileDescriptor {
 	return f
 }

go.mod

@@ -8,13 +8,13 @@ require (
 	github.com/jhump/gopoet v0.1.0
 	github.com/jhump/goprotoc v0.5.0
 	google.golang.org/grpc v1.61.0
-	google.golang.org/protobuf v1.33.1-0.20240319125436-3039476726e4
+	google.golang.org/protobuf v1.33.1-0.20240408130810-98873a205002
 )
 
 require (
-	golang.org/x/net v0.18.0 // indirect
+	golang.org/x/net v0.22.0 // indirect
 	golang.org/x/sync v0.6.0 // indirect
-	golang.org/x/sys v0.14.0 // indirect
+	golang.org/x/sys v0.18.0 // indirect
 	golang.org/x/text v0.14.0 // indirect
 	google.golang.org/genproto/googleapis/rpc v0.0.0-20231106174013-bbf56f31fb17 // indirect
 )

go.sum

@@ -60,8 +60,8 @@ golang.org/x/net v0.0.0-20190213061140-3a22650c66bd/go.mod h1:mL1N/T3taQHkDXs73r
 golang.org/x/net v0.0.0-20190311183353-d8887717615a/go.mod h1:t9HGtf8HONx5eT2rtn7q6eTqICYqUVnKs3thJo3Qplg=
 golang.org/x/net v0.0.0-20190404232315-eb5bcb51f2a3/go.mod h1:t9HGtf8HONx5eT2rtn7q6eTqICYqUVnKs3thJo3Qplg=
 golang.org/x/net v0.0.0-20200625001655-4c5254603344/go.mod h1:/O7V0waA8r7cgGh81Ro3o1hOxt32SMVPicZroKQ2sZA=
-golang.org/x/net v0.18.0 h1:mIYleuAkSbHh0tCv7RvjL3F6ZVbLjq4+R7zbOn3Kokg=
-golang.org/x/net v0.18.0/go.mod h1:/czyP5RqHAH4odGYxBJ1qz0+CE5WZ+2j1YgoEo8F2jQ=
+golang.org/x/net v0.22.0 h1:9sGLhx7iRIHEiX0oAJ3MRZMUCElJgy7Br1nO+AMN3Tc=
+golang.org/x/net v0.22.0/go.mod h1:JKghWKKOSdJwpW2GEx0Ja7fmaKnMsbu+MWVZTokSYmg=
 golang.org/x/oauth2 v0.0.0-20180821212333-d2e6202438be/go.mod h1:N/0e6XlmueqKjAGxoOufVs8QHGRruUQn6yWY3a++T0U=
 golang.org/x/sync v0.0.0-20180314180146-1d60e4601c6f/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
 golang.org/x/sync v0.0.0-20181108010431-42b317875d0f/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
@@ -73,8 +73,8 @@ golang.org/x/sys v0.0.0-20180830151530-49385e6e1522/go.mod h1:STP8DvDyc/dI5b8T5h
 golang.org/x/sys v0.0.0-20190215142949-d0b11bdaac8a/go.mod h1:STP8DvDyc/dI5b8T5hshtkjS+E42TnysNCUPdjciGhY=
 golang.org/x/sys v0.0.0-20190412213103-97732733099d/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
 golang.org/x/sys v0.0.0-20200323222414-85ca7c5b95cd/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
-golang.org/x/sys v0.14.0 h1:Vz7Qs629MkJkGyHxUlRHizWJRG2j8fbQKjELVSNhy7Q=
-golang.org/x/sys v0.14.0/go.mod h1:/VUhepiaJMQUp4+oa/7Zr1D23ma6VTLIYjOOTFZPUcA=
+golang.org/x/sys v0.18.0 h1:DBdB3niSjOA/O0blCZBqDefyWNYveAYMNF1Wum0DYQ4=
+golang.org/x/sys v0.18.0/go.mod h1:/VUhepiaJMQUp4+oa/7Zr1D23ma6VTLIYjOOTFZPUcA=
 golang.org/x/text v0.3.0/go.mod h1:NqM8EUOU14njkJ3fqMW+pc6Ldnwhi/IjpwHt7yyuwOQ=
 golang.org/x/text v0.3.2/go.mod h1:bEr9sfX3Q8Zfm5fL9x+3itogRgK3+ptLWKqgva+5dAk=
 golang.org/x/text v0.14.0 h1:ScX5w1eTa3QqT8oi6+ziP7dTV1S2+ALU0bI+0zXKWiQ=
@@ -110,8 +110,8 @@ google.golang.org/protobuf v1.23.1-0.20200526195155-81db48ad09cc/go.mod h1:EGpAD
 google.golang.org/protobuf v1.25.0/go.mod h1:9JNX74DMeImyA3h4bdi1ymwjUzf21/xIlbajtzgsN7c=
 google.golang.org/protobuf v1.26.0-rc.1/go.mod h1:jlhhOSvTdKEhbULTjvd4ARK9grFBp09yW+WbY/TyQbw=
 google.golang.org/protobuf v1.26.0/go.mod h1:9q0QmTI4eRPtz6boOQmLYwt+qCgq0jsYwAQnmE0givc=
-google.golang.org/protobuf v1.33.1-0.20240319125436-3039476726e4 h1:fea3X9JPnW4oM9z1ctAuAN7kAnM/YbdI7QHCZXKLVMk=
-google.golang.org/protobuf v1.33.1-0.20240319125436-3039476726e4/go.mod h1:c6P6GXX6sHbq/GpV6MGZEdwhWPcYBgnhAHhKbcUYpos=
+google.golang.org/protobuf v1.33.1-0.20240408130810-98873a205002 h1:V7Da7qt0MkY3noVANIMVBk28nOnijADeOR3i5Hcvpj4=
+google.golang.org/protobuf v1.33.1-0.20240408130810-98873a205002/go.mod h1:c6P6GXX6sHbq/GpV6MGZEdwhWPcYBgnhAHhKbcUYpos=
 gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
 gopkg.in/check.v1 v1.0.0-20190902080502-41f04d3bba15/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
 gopkg.in/yaml.v2 v2.2.2/go.mod h1:hI93XBmqTisBFMUTm0b8Fm+jr3Dg1NNxqwp+5A1VGuI=