compiler/protogen: support -experimental_strip_nonfunctional_codegen
This flag is used by the (Google-internal) editions codegen test.
Having the functionality in the open source repository reduces
our maintenance burden (fewer/smaller patches).
Change-Id: Idb9c95e9b2cb8922584bcb7ca13a8ddef4347af0
Reviewed-on: https://go-review.googlesource.com/c/protobuf/+/606735
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Lasse Folger <lassefolger@google.com>
diff --git a/cmd/protoc-gen-go/internal_gengo/main.go b/cmd/protoc-gen-go/internal_gengo/main.go
index 5402dfd..1a3a342 100644
--- a/cmd/protoc-gen-go/internal_gengo/main.go
+++ b/cmd/protoc-gen-go/internal_gengo/main.go
@@ -76,11 +76,14 @@
g := gen.NewGeneratedFile(filename, file.GoImportPath)
f := newFileInfo(file)
- genStandaloneComments(g, f, int32(genid.FileDescriptorProto_Syntax_field_number))
- genGeneratedHeader(gen, g, f)
- genStandaloneComments(g, f, int32(genid.FileDescriptorProto_Package_field_number))
+ var packageDoc protogen.Comments
+ if !gen.InternalStripForEditionsDiff() {
+ genStandaloneComments(g, f, int32(genid.FileDescriptorProto_Syntax_field_number))
+ genGeneratedHeader(gen, g, f)
+ genStandaloneComments(g, f, int32(genid.FileDescriptorProto_Package_field_number))
- packageDoc := genPackageKnownComment(f)
+ packageDoc = genPackageKnownComment(f)
+ }
g.P(packageDoc, "package ", f.GoPackageName)
g.P()
@@ -106,7 +109,23 @@
}
genExtensions(g, f)
- genReflectFileDescriptor(gen, g, f)
+ // The descriptor contains a lot of information about the syntax which is
+ // quite different between the proto2/3 version of a file and the equivalent
+ // editions version. For example, when a proto3 file is translated from
+ // proto3 to editions every field in that file that is marked optional in
+ // proto3 will have a features.field_presence option set.
+ // Another problem is that the descriptor contains implementation details
+ // that are not relevant for the semantic. For example, proto3 optional
+ // fields are implemented as oneof fields with one case. The descriptor
+ // contains different information about oneofs. If the file is translated
+ // to editions it no longer is treated as a oneof with one case and thus
+ // none of the oneof specific information is generated.
+ // To be able to compare the descriptor before and after translation of the
+ // associated proto file, we would need to trim many parts. This would lead
+ // to a brittle implementation in case the translation ever changes.
+ if !g.InternalStripForEditionsDiff() {
+ genReflectFileDescriptor(gen, g, f)
+ }
return g
}
diff --git a/cmd/protoc-gen-go/main.go b/cmd/protoc-gen-go/main.go
index 431fbb9..f3b5acb 100644
--- a/cmd/protoc-gen-go/main.go
+++ b/cmd/protoc-gen-go/main.go
@@ -35,11 +35,13 @@
}
var (
- flags flag.FlagSet
- plugins = flags.String("plugins", "", "deprecated option")
+ flags flag.FlagSet
+ plugins = flags.String("plugins", "", "deprecated option")
+ experimentalStripNonFunctionalCodegen = flags.Bool("experimental_strip_nonfunctional_codegen", false, "experimental_strip_nonfunctional_codegen true means that the plugin will not emit certain parts of the generated code in order to make it possible to compare a proto2/proto3 file with its equivalent (according to proto spec) editions file. Primarily, this is the encoded descriptor.")
)
protogen.Options{
- ParamFunc: flags.Set,
+ ParamFunc: flags.Set,
+ InternalStripForEditionsDiff: experimentalStripNonFunctionalCodegen,
}.Run(func(gen *protogen.Plugin) error {
if *plugins != "" {
return errors.New("protoc-gen-go: plugins are not supported; use 'protoc --go-grpc_out=...' to generate gRPC\n\n" +
diff --git a/compiler/protogen/protogen.go b/compiler/protogen/protogen.go
index 3c11644..966728e 100644
--- a/compiler/protogen/protogen.go
+++ b/compiler/protogen/protogen.go
@@ -152,6 +152,18 @@
// imported by a generated file. It returns the import path to use
// for this package.
ImportRewriteFunc func(GoImportPath) GoImportPath
+
+ // StripForEditionsDiff true means that the plugin will not emit certain
+ // parts of the generated code in order to make it possible to compare a
+ // proto2/proto3 file with its equivalent (according to proto spec)
+ // editions file. Primarily, this is the encoded descriptor.
+ //
+ // This must be a registered flag that is initialized by ParamFunc. It will
+ // be used by Options.New after it has parsed the flags.
+ //
+ // This struct field is for internal use by Go Protobuf only. Do not use it,
+ // we might remove it at any time.
+ InternalStripForEditionsDiff *bool
}
// New returns a new Plugin.
@@ -344,6 +356,15 @@
return gen, nil
}
+// InternalStripForEditionsDiff returns whether or not to strip non-functional
+// codegen for editions diff testing.
+//
+// This function is for internal use by Go Protobuf only. Do not use it, we
+// might remove it at any time.
+func (gen *Plugin) InternalStripForEditionsDiff() bool {
+ return gen.opts.InternalStripForEditionsDiff != nil && *gen.opts.InternalStripForEditionsDiff
+}
+
// Error records an error in code generation. The generator will report the
// error back to protoc and will not produce output.
func (gen *Plugin) Error(err error) {
@@ -538,7 +559,7 @@
Desc: desc,
GoIdent: newGoIdent(f, desc),
Location: loc,
- Comments: makeCommentSet(f.Desc.SourceLocations().ByDescriptor(desc)),
+ Comments: makeCommentSet(gen, f.Desc.SourceLocations().ByDescriptor(desc)),
}
gen.enumsByName[desc.FullName()] = enum
for i, vds := 0, enum.Desc.Values(); i < vds.Len(); i++ {
@@ -575,7 +596,7 @@
GoIdent: f.GoImportPath.Ident(name),
Parent: enum,
Location: loc,
- Comments: makeCommentSet(f.Desc.SourceLocations().ByDescriptor(desc)),
+ Comments: makeCommentSet(gen, f.Desc.SourceLocations().ByDescriptor(desc)),
}
}
@@ -607,7 +628,7 @@
Desc: desc,
GoIdent: newGoIdent(f, desc),
Location: loc,
- Comments: makeCommentSet(f.Desc.SourceLocations().ByDescriptor(desc)),
+ Comments: makeCommentSet(gen, f.Desc.SourceLocations().ByDescriptor(desc)),
}
gen.messagesByName[desc.FullName()] = message
for i, eds := 0, desc.Enums(); i < eds.Len(); i++ {
@@ -777,7 +798,7 @@
},
Parent: message,
Location: loc,
- Comments: makeCommentSet(f.Desc.SourceLocations().ByDescriptor(desc)),
+ Comments: makeCommentSet(gen, f.Desc.SourceLocations().ByDescriptor(desc)),
}
return field
}
@@ -844,7 +865,7 @@
GoName: parentPrefix + camelCased,
},
Location: loc,
- Comments: makeCommentSet(f.Desc.SourceLocations().ByDescriptor(desc)),
+ Comments: makeCommentSet(gen, f.Desc.SourceLocations().ByDescriptor(desc)),
}
}
@@ -869,7 +890,7 @@
Desc: desc,
GoName: strs.GoCamelCase(string(desc.Name())),
Location: loc,
- Comments: makeCommentSet(f.Desc.SourceLocations().ByDescriptor(desc)),
+ Comments: makeCommentSet(gen, f.Desc.SourceLocations().ByDescriptor(desc)),
}
for i, mds := 0, desc.Methods(); i < mds.Len(); i++ {
service.Methods = append(service.Methods, newMethod(gen, f, service, mds.Get(i)))
@@ -899,7 +920,7 @@
GoName: strs.GoCamelCase(string(desc.Name())),
Parent: service,
Location: loc,
- Comments: makeCommentSet(f.Desc.SourceLocations().ByDescriptor(desc)),
+ Comments: makeCommentSet(gen, f.Desc.SourceLocations().ByDescriptor(desc)),
}
return method
}
@@ -926,28 +947,30 @@
// A GeneratedFile is a generated file.
type GeneratedFile struct {
- gen *Plugin
- skip bool
- filename string
- goImportPath GoImportPath
- buf bytes.Buffer
- packageNames map[GoImportPath]GoPackageName
- usedPackageNames map[GoPackageName]bool
- manualImports map[GoImportPath]bool
- annotations map[string][]Annotation
+ gen *Plugin
+ skip bool
+ filename string
+ goImportPath GoImportPath
+ buf bytes.Buffer
+ packageNames map[GoImportPath]GoPackageName
+ usedPackageNames map[GoPackageName]bool
+ manualImports map[GoImportPath]bool
+ annotations map[string][]Annotation
+ stripForEditionsDiff bool
}
// NewGeneratedFile creates a new generated file with the given filename
// and import path.
func (gen *Plugin) NewGeneratedFile(filename string, goImportPath GoImportPath) *GeneratedFile {
g := &GeneratedFile{
- gen: gen,
- filename: filename,
- goImportPath: goImportPath,
- packageNames: make(map[GoImportPath]GoPackageName),
- usedPackageNames: make(map[GoPackageName]bool),
- manualImports: make(map[GoImportPath]bool),
- annotations: make(map[string][]Annotation),
+ gen: gen,
+ filename: filename,
+ goImportPath: goImportPath,
+ packageNames: make(map[GoImportPath]GoPackageName),
+ usedPackageNames: make(map[GoPackageName]bool),
+ manualImports: make(map[GoImportPath]bool),
+ annotations: make(map[string][]Annotation),
+ stripForEditionsDiff: gen.InternalStripForEditionsDiff(),
}
// All predeclared identifiers in Go are already used.
@@ -1020,6 +1043,17 @@
g.skip = false
}
+// InternalStripForEditionsDiff returns true if the plugin should not emit certain
+// parts of the generated code in order to make it possible to compare a
+// proto2/proto3 file with its equivalent (according to proto spec) editions
+// file. Primarily, this is the encoded descriptor.
+//
+// This function is for internal use by Go Protobuf only. Do not use it, we
+// might remove it at any time.
+func (g *GeneratedFile) InternalStripForEditionsDiff() bool {
+ return g.stripForEditionsDiff
+}
+
// Annotate associates a symbol in a generated Go file with a location in a
// source .proto file.
//
@@ -1298,7 +1332,10 @@
Trailing Comments
}
-func makeCommentSet(loc protoreflect.SourceLocation) CommentSet {
+func makeCommentSet(gen *Plugin, loc protoreflect.SourceLocation) CommentSet {
+ if gen.InternalStripForEditionsDiff() {
+ return CommentSet{}
+ }
var leadingDetached []Comments
for _, s := range loc.LeadingDetachedComments {
leadingDetached = append(leadingDetached, Comments(s))
