internal/cmd/generate-protos/main.go - protobuf - Git at Google

 // 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.

 //go:generate go run . -execute

 package main

 import (
 	"bytes"
 	"flag"
 	"fmt"
 	"go/format"
 	"io/ioutil"
 	"os"
 	"os/exec"
 	"path"
 	"path/filepath"
 	"regexp"
 	"sort"
 	"strconv"
 	"strings"

 	gengo "google.golang.org/protobuf/cmd/protoc-gen-go/internal_gengo"
 	"google.golang.org/protobuf/compiler/protogen"
 	"google.golang.org/protobuf/internal/detrand"
 )

 func init() {
 	// Determine repository root path.
 	out, err := exec.Command("git", "rev-parse", "--show-toplevel").CombinedOutput()
 	check(err)
 	repoRoot = strings.TrimSpace(string(out))

 	// Determine the module path.
 	cmd := exec.Command("go", "list", "-m", "-f", "{{.Path}}")
 	cmd.Dir = repoRoot
 	out, err = cmd.CombinedOutput()
 	check(err)
 	modulePath = strings.TrimSpace(string(out))

 	// When the environment variable RUN_AS_PROTOC_PLUGIN is set,
 	// we skip running main and instead act as a protoc plugin.
 	// This allows the binary to pass itself to protoc.
 	if plugin := os.Getenv("RUN_AS_PROTOC_PLUGIN"); plugin != "" {
 		// Disable deliberate output instability for generated files.
 		// This is reasonable since we fully control the output.
 		detrand.Disable()

 		protogen.Options{}.Run(func(gen *protogen.Plugin) error {
 			for _, file := range gen.Files {
 				if file.Generate {
 					gengo.GenerateVersionMarkers = false
 					gengo.GenerateFile(gen, file)
 					generateIdentifiers(gen, file)
 					generateSouceContextStringer(gen, file)
 				}
 			}
 			gen.SupportedFeatures = gengo.SupportedFeatures
 			return nil
 		})
 		os.Exit(0)
 	}
 }

 var (
 	run        bool
 	protoRoot  string
 	repoRoot   string
 	modulePath string

 	generatedPreamble = []string{
 		"// 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.",
 		"",
 		"// Code generated by generate-protos. DO NOT EDIT.",
 		"",
 	}
 )

 func main() {
 	flag.BoolVar(&run, "execute", false, "Write generated files to destination.")
 	flag.StringVar(&protoRoot, "protoroot", os.Getenv("PROTOBUF_ROOT"), "The root of the protobuf source tree.")
 	flag.Parse()
 	if protoRoot == "" {
 		panic("protobuf source root is not set")
 	}

 	generateLocalProtos()
 	generateRemoteProtos()
 }

 func generateLocalProtos() {
 	tmpDir, err := ioutil.TempDir(repoRoot, "tmp")
 	check(err)
 	defer os.RemoveAll(tmpDir)

 	// Generate all local proto files (except version-locked files).
 	dirs := []struct {
 		path     string
 		pkgPaths map[string]string // mapping of .proto path to Go package path
 		annotate map[string]bool   // .proto files to annotate
 		exclude  map[string]bool   // .proto files to exclude from generation
 	}{{
 		path:     "cmd/protoc-gen-go/testdata",
 		pkgPaths: map[string]string{"cmd/protoc-gen-go/testdata/nopackage/nopackage.proto": "google.golang.org/protobuf/cmd/protoc-gen-go/testdata/nopackage"},
 		annotate: map[string]bool{"cmd/protoc-gen-go/testdata/annotations/annotations.proto": true},
 	}, {
 		path:    "internal/testprotos",
 		exclude: map[string]bool{"internal/testprotos/irregular/irregular.proto": true},
 	}}
 	excludeRx := regexp.MustCompile(`legacy/.*/`)
 	for _, d := range dirs {
 		subDirs := map[string]bool{}

 		srcDir := filepath.Join(repoRoot, filepath.FromSlash(d.path))
 		filepath.Walk(srcDir, func(srcPath string, _ os.FileInfo, _ error) error {
 			if !strings.HasSuffix(srcPath, ".proto") || excludeRx.MatchString(srcPath) {
 				return nil
 			}
 			relPath, err := filepath.Rel(repoRoot, srcPath)
 			check(err)

 			srcRelPath, err := filepath.Rel(srcDir, srcPath)
 			check(err)
 			subDirs[filepath.Dir(srcRelPath)] = true

 			if d.exclude[filepath.ToSlash(relPath)] {
 				return nil
 			}

 			opts := "module=" + modulePath
 			for protoPath, goPkgPath := range d.pkgPaths {
 				opts += fmt.Sprintf(",M%v=%v", protoPath, goPkgPath)
 			}
 			if d.annotate[filepath.ToSlash(relPath)] {
 				opts += ",annotate_code"
 			}
 			protoc("-I"+filepath.Join(protoRoot, "src"), "-I"+repoRoot, "--go_out="+opts+":"+tmpDir, relPath)
 			return nil
 		})

 		// For directories in testdata, generate a test that links in all
 		// generated packages to ensure that it builds and initializes properly.
 		// This is done because "go build ./..." does not build sub-packages
 		// under testdata.
 		if filepath.Base(d.path) == "testdata" {
 			var imports []string
 			for sd := range subDirs {
 				imports = append(imports, fmt.Sprintf("_ %q", path.Join(modulePath, d.path, filepath.ToSlash(sd))))
 			}
 			sort.Strings(imports)

 			s := strings.Join(append(generatedPreamble, []string{
 				"package main",
 				"",
 				"import (" + strings.Join(imports, "\n") + ")",
 			}...), "\n")
 			b, err := format.Source([]byte(s))
 			check(err)
 			check(ioutil.WriteFile(filepath.Join(tmpDir, filepath.FromSlash(d.path+"/gen_test.go")), b, 0664))
 		}
 	}

 	syncOutput(repoRoot, tmpDir)
 }

 func generateRemoteProtos() {
 	tmpDir, err := ioutil.TempDir(repoRoot, "tmp")
 	check(err)
 	defer os.RemoveAll(tmpDir)

 	// Generate all remote proto files.
 	files := []struct{ prefix, path, goPkgPath string }{
 		// Well-known protos.
 		{"src", "google/protobuf/any.proto", ""},
 		{"src", "google/protobuf/api.proto", ""},
 		{"src", "google/protobuf/duration.proto", ""},
 		{"src", "google/protobuf/empty.proto", ""},
 		{"src", "google/protobuf/field_mask.proto", ""},
 		{"src", "google/protobuf/source_context.proto", ""},
 		{"src", "google/protobuf/struct.proto", ""},
 		{"src", "google/protobuf/timestamp.proto", ""},
 		{"src", "google/protobuf/type.proto", ""},
 		{"src", "google/protobuf/wrappers.proto", ""},

 		// Compiler protos.
 		{"src", "google/protobuf/compiler/plugin.proto", ""},
 		{"src", "google/protobuf/descriptor.proto", ""},

 		// Conformance protos.
 		{"", "conformance/conformance.proto", "google.golang.org/protobuf/internal/testprotos/conformance;conformance"},
 		{"src", "google/protobuf/test_messages_proto2.proto", "google.golang.org/protobuf/internal/testprotos/conformance;conformance"},
 		{"src", "google/protobuf/test_messages_proto3.proto", "google.golang.org/protobuf/internal/testprotos/conformance;conformance"},

 		// Benchmark protos.
 		{"benchmarks", "benchmarks.proto", "google.golang.org/protobuf/internal/testprotos/benchmarks;benchmarks"},
 		{"benchmarks", "datasets/google_message1/proto2/benchmark_message1_proto2.proto", "google.golang.org/protobuf/internal/testprotos/benchmarks/datasets/google_message1/proto2;proto2"},
 		{"benchmarks", "datasets/google_message1/proto3/benchmark_message1_proto3.proto", "google.golang.org/protobuf/internal/testprotos/benchmarks/datasets/google_message1/proto3;proto3"},
 		{"benchmarks", "datasets/google_message2/benchmark_message2.proto", "google.golang.org/protobuf/internal/testprotos/benchmarks/datasets/google_message2;google_message2"},
 		{"benchmarks", "datasets/google_message3/benchmark_message3.proto", "google.golang.org/protobuf/internal/testprotos/benchmarks/datasets/google_message3;google_message3"},
 		{"benchmarks", "datasets/google_message3/benchmark_message3_1.proto", "google.golang.org/protobuf/internal/testprotos/benchmarks/datasets/google_message3;google_message3"},
 		{"benchmarks", "datasets/google_message3/benchmark_message3_2.proto", "google.golang.org/protobuf/internal/testprotos/benchmarks/datasets/google_message3;google_message3"},
 		{"benchmarks", "datasets/google_message3/benchmark_message3_3.proto", "google.golang.org/protobuf/internal/testprotos/benchmarks/datasets/google_message3;google_message3"},
 		{"benchmarks", "datasets/google_message3/benchmark_message3_4.proto", "google.golang.org/protobuf/internal/testprotos/benchmarks/datasets/google_message3;google_message3"},
 		{"benchmarks", "datasets/google_message3/benchmark_message3_5.proto", "google.golang.org/protobuf/internal/testprotos/benchmarks/datasets/google_message3;google_message3"},
 		{"benchmarks", "datasets/google_message3/benchmark_message3_6.proto", "google.golang.org/protobuf/internal/testprotos/benchmarks/datasets/google_message3;google_message3"},
 		{"benchmarks", "datasets/google_message3/benchmark_message3_7.proto", "google.golang.org/protobuf/internal/testprotos/benchmarks/datasets/google_message3;google_message3"},
 		{"benchmarks", "datasets/google_message3/benchmark_message3_8.proto", "google.golang.org/protobuf/internal/testprotos/benchmarks/datasets/google_message3;google_message3"},
 		{"benchmarks", "datasets/google_message4/benchmark_message4.proto", "google.golang.org/protobuf/internal/testprotos/benchmarks/datasets/google_message4;google_message4"},
 		{"benchmarks", "datasets/google_message4/benchmark_message4_1.proto", "google.golang.org/protobuf/internal/testprotos/benchmarks/datasets/google_message4;google_message4"},
 		{"benchmarks", "datasets/google_message4/benchmark_message4_2.proto", "google.golang.org/protobuf/internal/testprotos/benchmarks/datasets/google_message4;google_message4"},
 		{"benchmarks", "datasets/google_message4/benchmark_message4_3.proto", "google.golang.org/protobuf/internal/testprotos/benchmarks/datasets/google_message4;google_message4"},
 	}

 	opts := "module=" + modulePath
 	for _, file := range files {
 		if file.goPkgPath != "" {
 			opts += fmt.Sprintf(",M%v=%v", file.path, file.goPkgPath)
 		}
 	}
 	for _, f := range files {
 		protoc("-I"+filepath.Join(protoRoot, f.prefix), "--go_out="+opts+":"+tmpDir, f.path)
 	}

 	syncOutput(repoRoot, tmpDir)
 }

 func protoc(args ...string) {
 	// TODO: Remove --experimental_allow_proto3_optional flag.
 	cmd := exec.Command("protoc", "--plugin=protoc-gen-go="+os.Args[0], "--experimental_allow_proto3_optional")
 	cmd.Args = append(cmd.Args, args...)
 	cmd.Env = append(os.Environ(), "RUN_AS_PROTOC_PLUGIN=1")
 	out, err := cmd.CombinedOutput()
 	if err != nil {
 		fmt.Printf("executing: %v\n%s\n", strings.Join(cmd.Args, " "), out)
 	}
 	check(err)
 }

 // generateIdentifiers generates an internal package for descriptor.proto
 // and well-known types.
 func generateIdentifiers(gen *protogen.Plugin, file *protogen.File) {
 	if file.Desc.Package() != "google.protobuf" {
 		return
 	}

 	importPath := modulePath + "/internal/genid"
 	base := strings.TrimSuffix(path.Base(file.Desc.Path()), ".proto")
 	g := gen.NewGeneratedFile(importPath+"/"+base+"_gen.go", protogen.GoImportPath(importPath))
 	for _, s := range generatedPreamble {
 		g.P(s)
 	}
 	g.P("package ", path.Base(importPath))
 	g.P()

 	g.P("const ", file.GoDescriptorIdent.GoName, " = ", strconv.Quote(file.Desc.Path()))
 	g.P()

 	var processEnums func([]*protogen.Enum)
 	var processMessages func([]*protogen.Message)
 	const protoreflectPackage = protogen.GoImportPath("google.golang.org/protobuf/reflect/protoreflect")
 	processEnums = func(enums []*protogen.Enum) {
 		for _, enum := range enums {
 			g.P("// Full and short names for ", enum.Desc.FullName(), ".")
 			g.P("const (")
 			g.P(enum.GoIdent.GoName, "_enum_fullname = ", strconv.Quote(string(enum.Desc.FullName())))
 			g.P(enum.GoIdent.GoName, "_enum_name = ", strconv.Quote(string(enum.Desc.Name())))
 			g.P(")")
 			g.P()
 		}
 	}
 	processMessages = func(messages []*protogen.Message) {
 		for _, message := range messages {
 			g.P("// Names for ", message.Desc.FullName(), ".")
 			g.P("const (")
 			g.P(message.GoIdent.GoName, "_message_name ", protoreflectPackage.Ident("Name"), " = ", strconv.Quote(string(message.Desc.Name())))
 			g.P(message.GoIdent.GoName, "_message_fullname ", protoreflectPackage.Ident("FullName"), " = ", strconv.Quote(string(message.Desc.FullName())))
 			g.P(")")
 			g.P()

 			if len(message.Fields) > 0 {
 				g.P("// Field names for ", message.Desc.FullName(), ".")
 				g.P("const (")
 				for _, field := range message.Fields {
 					g.P(message.GoIdent.GoName, "_", field.GoName, "_field_name ", protoreflectPackage.Ident("Name"), " = ", strconv.Quote(string(field.Desc.Name())))
 				}
 				g.P()
 				for _, field := range message.Fields {
 					g.P(message.GoIdent.GoName, "_", field.GoName, "_field_fullname ", protoreflectPackage.Ident("FullName"), " = ", strconv.Quote(string(field.Desc.FullName())))
 				}
 				g.P(")")
 				g.P()

 				g.P("// Field numbers for ", message.Desc.FullName(), ".")
 				g.P("const (")
 				for _, field := range message.Fields {
 					g.P(message.GoIdent.GoName, "_", field.GoName, "_field_number ", protoreflectPackage.Ident("FieldNumber"), " = ", field.Desc.Number())
 				}
 				g.P(")")
 				g.P()
 			}

 			if len(message.Oneofs) > 0 {
 				g.P("// Oneof names for ", message.Desc.FullName(), ".")
 				g.P("const (")
 				for _, oneof := range message.Oneofs {
 					g.P(message.GoIdent.GoName, "_", oneof.GoName, "_oneof_name ", protoreflectPackage.Ident("Name"), " = ", strconv.Quote(string(oneof.Desc.Name())))
 				}
 				g.P()
 				for _, oneof := range message.Oneofs {
 					g.P(message.GoIdent.GoName, "_", oneof.GoName, "_oneof_fullname ", protoreflectPackage.Ident("FullName"), " = ", strconv.Quote(string(oneof.Desc.FullName())))
 				}
 				g.P(")")
 				g.P()
 			}

 			processEnums(message.Enums)
 			processMessages(message.Messages)
 		}
 	}
 	processEnums(file.Enums)
 	processMessages(file.Messages)
 }

 // generateSouceContextStringer generates the implementation for the
 // protoreflect.SourcePath.String method by using information present
 // in the descriptor.proto.
 func generateSouceContextStringer(gen *protogen.Plugin, file *protogen.File) {
 	if file.Desc.Path() != "google/protobuf/descriptor.proto" {
 		return
 	}

 	importPath := modulePath + "/reflect/protoreflect"
 	g := gen.NewGeneratedFile(importPath+"/source_gen.go", protogen.GoImportPath(importPath))
 	for _, s := range generatedPreamble {
 		g.P(s)
 	}
 	g.P("package ", path.Base(importPath))
 	g.P()

 	var messages []*protogen.Message
 	for _, message := range file.Messages {
 		if message.Desc.Name() == "FileDescriptorProto" {
 			messages = append(messages, message)
 		}
 	}
 	seen := make(map[*protogen.Message]bool)

 	for len(messages) > 0 {
 		m := messages[0]
 		messages = messages[1:]
 		if seen[m] {
 			continue
 		}
 		seen[m] = true

 		g.P("func (p *SourcePath) append", m.GoIdent.GoName, "(b []byte) []byte {")
 		g.P("if len(*p) == 0 { return b }")
 		g.P("switch (*p)[0] {")
 		for _, f := range m.Fields {
 			g.P("case ", f.Desc.Number(), ":")
 			var cardinality string
 			switch {
 			case f.Desc.IsMap():
 				panic("maps are not supported")
 			case f.Desc.IsList():
 				cardinality = "Repeated"
 			default:
 				cardinality = "Singular"
 			}
 			nextAppender := "nil"
 			if f.Message != nil {
 				nextAppender = "(*SourcePath).append" + f.Message.GoIdent.GoName
 				messages = append(messages, f.Message)
 			}
 			g.P("b = p.append", cardinality, "Field(b, ", strconv.Quote(string(f.Desc.Name())), ", ", nextAppender, ")")
 		}
 		g.P("}")
 		g.P("return b")
 		g.P("}")
 		g.P()
 	}
 }

 func syncOutput(dstDir, srcDir string) {
 	filepath.Walk(srcDir, func(srcPath string, _ os.FileInfo, _ error) error {
 		if !strings.HasSuffix(srcPath, ".go") && !strings.HasSuffix(srcPath, ".meta") {
 			return nil
 		}
 		relPath, err := filepath.Rel(srcDir, srcPath)
 		check(err)
 		dstPath := filepath.Join(dstDir, relPath)

 		if run {
 			if copyFile(dstPath, srcPath) {
 				fmt.Println("#", relPath)
 			}
 		} else {
 			cmd := exec.Command("diff", dstPath, srcPath, "-N", "-u")
 			cmd.Stdout = os.Stdout
 			cmd.Run()
 		}
 		return nil
 	})
 }

 func copyFile(dstPath, srcPath string) (changed bool) {
 	src, err := ioutil.ReadFile(srcPath)
 	check(err)
 	check(os.MkdirAll(filepath.Dir(dstPath), 0775))
 	dst, _ := ioutil.ReadFile(dstPath)
 	if bytes.Equal(src, dst) {
 		return false
 	}
 	check(ioutil.WriteFile(dstPath, src, 0664))
 	return true
 }

 func check(err error) {
 	if err != nil {
 		panic(err)
 	}
 }
	// 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.

	//go:generate go run . -execute

	package main

	import (
	"bytes"
	"flag"
	"fmt"
	"go/format"
	"io/ioutil"
	"os"
	"os/exec"
	"path"
	"path/filepath"
	"regexp"
	"sort"
	"strconv"
	"strings"

	gengo "google.golang.org/protobuf/cmd/protoc-gen-go/internal_gengo"
	"google.golang.org/protobuf/compiler/protogen"
	"google.golang.org/protobuf/internal/detrand"
	)

	func init() {
	// Determine repository root path.
	out, err := exec.Command("git", "rev-parse", "--show-toplevel").CombinedOutput()
	check(err)
	repoRoot = strings.TrimSpace(string(out))

	// Determine the module path.
	cmd := exec.Command("go", "list", "-m", "-f", "{{.Path}}")
	cmd.Dir = repoRoot
	out, err = cmd.CombinedOutput()
	check(err)
	modulePath = strings.TrimSpace(string(out))

	// When the environment variable RUN_AS_PROTOC_PLUGIN is set,
	// we skip running main and instead act as a protoc plugin.
	// This allows the binary to pass itself to protoc.
	if plugin := os.Getenv("RUN_AS_PROTOC_PLUGIN"); plugin != "" {
	// Disable deliberate output instability for generated files.
	// This is reasonable since we fully control the output.
	detrand.Disable()

	protogen.Options{}.Run(func(gen *protogen.Plugin) error {
	for _, file := range gen.Files {
	if file.Generate {
	gengo.GenerateVersionMarkers = false
	gengo.GenerateFile(gen, file)
	generateIdentifiers(gen, file)
	generateSouceContextStringer(gen, file)
	}
	}
	gen.SupportedFeatures = gengo.SupportedFeatures
	return nil
	})
	os.Exit(0)
	}
	}

	var (
	run bool
	protoRoot string
	repoRoot string
	modulePath string

	generatedPreamble = []string{
	"// 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.",
	"",
	"// Code generated by generate-protos. DO NOT EDIT.",
	"",
	}
	)

	func main() {
	flag.BoolVar(&run, "execute", false, "Write generated files to destination.")
	flag.StringVar(&protoRoot, "protoroot", os.Getenv("PROTOBUF_ROOT"), "The root of the protobuf source tree.")
	flag.Parse()
	if protoRoot == "" {
	panic("protobuf source root is not set")
	}

	generateLocalProtos()
	generateRemoteProtos()
	}

	func generateLocalProtos() {
	tmpDir, err := ioutil.TempDir(repoRoot, "tmp")
	check(err)
	defer os.RemoveAll(tmpDir)

	// Generate all local proto files (except version-locked files).
	dirs := []struct {
	path string
	pkgPaths map[string]string // mapping of .proto path to Go package path
	annotate map[string]bool // .proto files to annotate
	exclude map[string]bool // .proto files to exclude from generation
	}{{
	path: "cmd/protoc-gen-go/testdata",
	pkgPaths: map[string]string{"cmd/protoc-gen-go/testdata/nopackage/nopackage.proto": "google.golang.org/protobuf/cmd/protoc-gen-go/testdata/nopackage"},
	annotate: map[string]bool{"cmd/protoc-gen-go/testdata/annotations/annotations.proto": true},
	}, {
	path: "internal/testprotos",
	exclude: map[string]bool{"internal/testprotos/irregular/irregular.proto": true},
	}}
	excludeRx := regexp.MustCompile(`legacy/.*/`)
	for _, d := range dirs {
	subDirs := map[string]bool{}

	srcDir := filepath.Join(repoRoot, filepath.FromSlash(d.path))
	filepath.Walk(srcDir, func(srcPath string, _ os.FileInfo, _ error) error {
	if !strings.HasSuffix(srcPath, ".proto") \|\| excludeRx.MatchString(srcPath) {
	return nil
	}
	relPath, err := filepath.Rel(repoRoot, srcPath)
	check(err)

	srcRelPath, err := filepath.Rel(srcDir, srcPath)
	check(err)
	subDirs[filepath.Dir(srcRelPath)] = true

	if d.exclude[filepath.ToSlash(relPath)] {
	return nil
	}

	opts := "module=" + modulePath
	for protoPath, goPkgPath := range d.pkgPaths {
	opts += fmt.Sprintf(",M%v=%v", protoPath, goPkgPath)
	}
	if d.annotate[filepath.ToSlash(relPath)] {
	opts += ",annotate_code"
	}
	protoc("-I"+filepath.Join(protoRoot, "src"), "-I"+repoRoot, "--go_out="+opts+":"+tmpDir, relPath)
	return nil
	})

	// For directories in testdata, generate a test that links in all
	// generated packages to ensure that it builds and initializes properly.
	// This is done because "go build ./..." does not build sub-packages
	// under testdata.
	if filepath.Base(d.path) == "testdata" {
	var imports []string
	for sd := range subDirs {
	imports = append(imports, fmt.Sprintf("_ %q", path.Join(modulePath, d.path, filepath.ToSlash(sd))))
	}
	sort.Strings(imports)

	s := strings.Join(append(generatedPreamble, []string{
	"package main",
	"",
	"import (" + strings.Join(imports, "\n") + ")",
	}...), "\n")
	b, err := format.Source([]byte(s))
	check(err)
	check(ioutil.WriteFile(filepath.Join(tmpDir, filepath.FromSlash(d.path+"/gen_test.go")), b, 0664))
	}
	}

	syncOutput(repoRoot, tmpDir)
	}

	func generateRemoteProtos() {
	tmpDir, err := ioutil.TempDir(repoRoot, "tmp")
	check(err)
	defer os.RemoveAll(tmpDir)

	// Generate all remote proto files.
	files := []struct{ prefix, path, goPkgPath string }{
	// Well-known protos.
	{"src", "google/protobuf/any.proto", ""},
	{"src", "google/protobuf/api.proto", ""},
	{"src", "google/protobuf/duration.proto", ""},
	{"src", "google/protobuf/empty.proto", ""},
	{"src", "google/protobuf/field_mask.proto", ""},
	{"src", "google/protobuf/source_context.proto", ""},
	{"src", "google/protobuf/struct.proto", ""},
	{"src", "google/protobuf/timestamp.proto", ""},
	{"src", "google/protobuf/type.proto", ""},
	{"src", "google/protobuf/wrappers.proto", ""},

	// Compiler protos.
	{"src", "google/protobuf/compiler/plugin.proto", ""},
	{"src", "google/protobuf/descriptor.proto", ""},

	// Conformance protos.
	{"", "conformance/conformance.proto", "google.golang.org/protobuf/internal/testprotos/conformance;conformance"},
	{"src", "google/protobuf/test_messages_proto2.proto", "google.golang.org/protobuf/internal/testprotos/conformance;conformance"},
	{"src", "google/protobuf/test_messages_proto3.proto", "google.golang.org/protobuf/internal/testprotos/conformance;conformance"},

	// Benchmark protos.
	{"benchmarks", "benchmarks.proto", "google.golang.org/protobuf/internal/testprotos/benchmarks;benchmarks"},
	{"benchmarks", "datasets/google_message1/proto2/benchmark_message1_proto2.proto", "google.golang.org/protobuf/internal/testprotos/benchmarks/datasets/google_message1/proto2;proto2"},
	{"benchmarks", "datasets/google_message1/proto3/benchmark_message1_proto3.proto", "google.golang.org/protobuf/internal/testprotos/benchmarks/datasets/google_message1/proto3;proto3"},
	{"benchmarks", "datasets/google_message2/benchmark_message2.proto", "google.golang.org/protobuf/internal/testprotos/benchmarks/datasets/google_message2;google_message2"},
	{"benchmarks", "datasets/google_message3/benchmark_message3.proto", "google.golang.org/protobuf/internal/testprotos/benchmarks/datasets/google_message3;google_message3"},
	{"benchmarks", "datasets/google_message3/benchmark_message3_1.proto", "google.golang.org/protobuf/internal/testprotos/benchmarks/datasets/google_message3;google_message3"},
	{"benchmarks", "datasets/google_message3/benchmark_message3_2.proto", "google.golang.org/protobuf/internal/testprotos/benchmarks/datasets/google_message3;google_message3"},
	{"benchmarks", "datasets/google_message3/benchmark_message3_3.proto", "google.golang.org/protobuf/internal/testprotos/benchmarks/datasets/google_message3;google_message3"},
	{"benchmarks", "datasets/google_message3/benchmark_message3_4.proto", "google.golang.org/protobuf/internal/testprotos/benchmarks/datasets/google_message3;google_message3"},
	{"benchmarks", "datasets/google_message3/benchmark_message3_5.proto", "google.golang.org/protobuf/internal/testprotos/benchmarks/datasets/google_message3;google_message3"},
	{"benchmarks", "datasets/google_message3/benchmark_message3_6.proto", "google.golang.org/protobuf/internal/testprotos/benchmarks/datasets/google_message3;google_message3"},
	{"benchmarks", "datasets/google_message3/benchmark_message3_7.proto", "google.golang.org/protobuf/internal/testprotos/benchmarks/datasets/google_message3;google_message3"},
	{"benchmarks", "datasets/google_message3/benchmark_message3_8.proto", "google.golang.org/protobuf/internal/testprotos/benchmarks/datasets/google_message3;google_message3"},
	{"benchmarks", "datasets/google_message4/benchmark_message4.proto", "google.golang.org/protobuf/internal/testprotos/benchmarks/datasets/google_message4;google_message4"},
	{"benchmarks", "datasets/google_message4/benchmark_message4_1.proto", "google.golang.org/protobuf/internal/testprotos/benchmarks/datasets/google_message4;google_message4"},
	{"benchmarks", "datasets/google_message4/benchmark_message4_2.proto", "google.golang.org/protobuf/internal/testprotos/benchmarks/datasets/google_message4;google_message4"},
	{"benchmarks", "datasets/google_message4/benchmark_message4_3.proto", "google.golang.org/protobuf/internal/testprotos/benchmarks/datasets/google_message4;google_message4"},
	}

	opts := "module=" + modulePath
	for _, file := range files {
	if file.goPkgPath != "" {
	opts += fmt.Sprintf(",M%v=%v", file.path, file.goPkgPath)
	}
	}
	for _, f := range files {
	protoc("-I"+filepath.Join(protoRoot, f.prefix), "--go_out="+opts+":"+tmpDir, f.path)
	}

	syncOutput(repoRoot, tmpDir)
	}

	func protoc(args ...string) {
	// TODO: Remove --experimental_allow_proto3_optional flag.
	cmd := exec.Command("protoc", "--plugin=protoc-gen-go="+os.Args[0], "--experimental_allow_proto3_optional")
	cmd.Args = append(cmd.Args, args...)
	cmd.Env = append(os.Environ(), "RUN_AS_PROTOC_PLUGIN=1")
	out, err := cmd.CombinedOutput()
	if err != nil {
	fmt.Printf("executing: %v\n%s\n", strings.Join(cmd.Args, " "), out)
	}
	check(err)
	}

	// generateIdentifiers generates an internal package for descriptor.proto
	// and well-known types.
	func generateIdentifiers(gen protogen.Plugin, file protogen.File) {
	if file.Desc.Package() != "google.protobuf" {
	return
	}

	importPath := modulePath + "/internal/genid"
	base := strings.TrimSuffix(path.Base(file.Desc.Path()), ".proto")
	g := gen.NewGeneratedFile(importPath+"/"+base+"_gen.go", protogen.GoImportPath(importPath))
	for _, s := range generatedPreamble {
	g.P(s)
	}
	g.P("package ", path.Base(importPath))
	g.P()

	g.P("const ", file.GoDescriptorIdent.GoName, " = ", strconv.Quote(file.Desc.Path()))
	g.P()

	var processEnums func([]*protogen.Enum)
	var processMessages func([]*protogen.Message)
	const protoreflectPackage = protogen.GoImportPath("google.golang.org/protobuf/reflect/protoreflect")
	processEnums = func(enums []*protogen.Enum) {
	for _, enum := range enums {
	g.P("// Full and short names for ", enum.Desc.FullName(), ".")
	g.P("const (")
	g.P(enum.GoIdent.GoName, "_enum_fullname = ", strconv.Quote(string(enum.Desc.FullName())))
	g.P(enum.GoIdent.GoName, "_enum_name = ", strconv.Quote(string(enum.Desc.Name())))
	g.P(")")
	g.P()
	}
	}
	processMessages = func(messages []*protogen.Message) {
	for _, message := range messages {
	g.P("// Names for ", message.Desc.FullName(), ".")
	g.P("const (")
	g.P(message.GoIdent.GoName, "_message_name ", protoreflectPackage.Ident("Name"), " = ", strconv.Quote(string(message.Desc.Name())))
	g.P(message.GoIdent.GoName, "_message_fullname ", protoreflectPackage.Ident("FullName"), " = ", strconv.Quote(string(message.Desc.FullName())))
	g.P(")")
	g.P()

	if len(message.Fields) > 0 {
	g.P("// Field names for ", message.Desc.FullName(), ".")
	g.P("const (")
	for _, field := range message.Fields {
	g.P(message.GoIdent.GoName, "_", field.GoName, "_field_name ", protoreflectPackage.Ident("Name"), " = ", strconv.Quote(string(field.Desc.Name())))
	}
	g.P()
	for _, field := range message.Fields {
	g.P(message.GoIdent.GoName, "_", field.GoName, "_field_fullname ", protoreflectPackage.Ident("FullName"), " = ", strconv.Quote(string(field.Desc.FullName())))
	}
	g.P(")")
	g.P()

	g.P("// Field numbers for ", message.Desc.FullName(), ".")
	g.P("const (")
	for _, field := range message.Fields {
	g.P(message.GoIdent.GoName, "_", field.GoName, "_field_number ", protoreflectPackage.Ident("FieldNumber"), " = ", field.Desc.Number())
	}
	g.P(")")
	g.P()
	}

	if len(message.Oneofs) > 0 {
	g.P("// Oneof names for ", message.Desc.FullName(), ".")
	g.P("const (")
	for _, oneof := range message.Oneofs {
	g.P(message.GoIdent.GoName, "_", oneof.GoName, "_oneof_name ", protoreflectPackage.Ident("Name"), " = ", strconv.Quote(string(oneof.Desc.Name())))
	}
	g.P()
	for _, oneof := range message.Oneofs {
	g.P(message.GoIdent.GoName, "_", oneof.GoName, "_oneof_fullname ", protoreflectPackage.Ident("FullName"), " = ", strconv.Quote(string(oneof.Desc.FullName())))
	}
	g.P(")")
	g.P()
	}

	processEnums(message.Enums)
	processMessages(message.Messages)
	}
	}
	processEnums(file.Enums)
	processMessages(file.Messages)
	}

	// generateSouceContextStringer generates the implementation for the
	// protoreflect.SourcePath.String method by using information present
	// in the descriptor.proto.
	func generateSouceContextStringer(gen protogen.Plugin, file protogen.File) {
	if file.Desc.Path() != "google/protobuf/descriptor.proto" {
	return
	}

	importPath := modulePath + "/reflect/protoreflect"
	g := gen.NewGeneratedFile(importPath+"/source_gen.go", protogen.GoImportPath(importPath))
	for _, s := range generatedPreamble {
	g.P(s)
	}
	g.P("package ", path.Base(importPath))
	g.P()

	var messages []*protogen.Message
	for _, message := range file.Messages {
	if message.Desc.Name() == "FileDescriptorProto" {
	messages = append(messages, message)
	}
	}
	seen := make(map[*protogen.Message]bool)

	for len(messages) > 0 {
	m := messages[0]
	messages = messages[1:]
	if seen[m] {
	continue
	}
	seen[m] = true

	g.P("func (p *SourcePath) append", m.GoIdent.GoName, "(b []byte) []byte {")
	g.P("if len(*p) == 0 { return b }")
	g.P("switch (*p)[0] {")
	for _, f := range m.Fields {
	g.P("case ", f.Desc.Number(), ":")
	var cardinality string
	switch {
	case f.Desc.IsMap():
	panic("maps are not supported")
	case f.Desc.IsList():
	cardinality = "Repeated"
	default:
	cardinality = "Singular"
	}
	nextAppender := "nil"
	if f.Message != nil {
	nextAppender = "(*SourcePath).append" + f.Message.GoIdent.GoName
	messages = append(messages, f.Message)
	}
	g.P("b = p.append", cardinality, "Field(b, ", strconv.Quote(string(f.Desc.Name())), ", ", nextAppender, ")")
	}
	g.P("}")
	g.P("return b")
	g.P("}")
	g.P()
	}
	}

	func syncOutput(dstDir, srcDir string) {
	filepath.Walk(srcDir, func(srcPath string, _ os.FileInfo, _ error) error {
	if !strings.HasSuffix(srcPath, ".go") && !strings.HasSuffix(srcPath, ".meta") {
	return nil
	}
	relPath, err := filepath.Rel(srcDir, srcPath)
	check(err)
	dstPath := filepath.Join(dstDir, relPath)

	if run {
	if copyFile(dstPath, srcPath) {
	fmt.Println("#", relPath)
	}
	} else {
	cmd := exec.Command("diff", dstPath, srcPath, "-N", "-u")
	cmd.Stdout = os.Stdout
	cmd.Run()
	}
	return nil
	})
	}

	func copyFile(dstPath, srcPath string) (changed bool) {
	src, err := ioutil.ReadFile(srcPath)
	check(err)
	check(os.MkdirAll(filepath.Dir(dstPath), 0775))
	dst, _ := ioutil.ReadFile(dstPath)
	if bytes.Equal(src, dst) {
	return false
	}
	check(ioutil.WriteFile(dstPath, src, 0664))
	return true
	}

	func check(err error) {
	if err != nil {
	panic(err)
	}
	}