refactor(cli): Migrate from alecthomas/kingpin to spf13/cobra.

This change migrates all of the current CLI code (and related tests) to
now use cobra. All functionality should stay identical with the flags.

The only changes present within the tests are the formatting of specific
errors, and how they differ between kingpin/cobra.

One potential breaking change that could impact users is that all
`gunk help...` commands now print to stdout, even if invalid. This is
not true for other errors, so it probably should not break any real
world applications.

This change can be linked back to spf13/cobra#1002.

go.mod

@@ -3,26 +3,26 @@ module github.com/gunk/gunk
 go 1.17
 
 require (
-	github.com/alecthomas/kingpin v2.2.6+incompatible
 	github.com/emicklei/proto v1.9.1
 	github.com/grpc-ecosystem/grpc-gateway/v2 v2.6.0
 	github.com/gunk/opt v0.1.0
 	github.com/karelbilek/dirchanges v0.0.0-20210218071031-880a92f1a313
 	github.com/kenshaw/ini v0.5.1
 	github.com/kenshaw/snaker v0.1.6
 	github.com/rogpeppe/go-internal v1.8.1-0.20211023094830-115ce09fd6b4
-	golang.org/x/sys v0.0.0-20211116061358-0a5406a5449c
+	github.com/spf13/cobra v1.2.1
+	golang.org/x/sys v0.0.0-20211117180635-dee7805ff2e1
 	golang.org/x/tools v0.1.8-0.20211102182255-bb4add04ddef
-	google.golang.org/genproto v0.0.0-20211116182654-e63d96a377c4
+	google.golang.org/genproto v0.0.0-20211117155847-120650a500bb
 	google.golang.org/protobuf v1.27.1
 	mvdan.cc/gofumpt v0.2.0
 )
 
 require (
-	github.com/alecthomas/template v0.0.0-20190718012654-fb15b899a751 // indirect
-	github.com/alecthomas/units v0.0.0-20210927113745-59d0afb8317a // indirect
 	github.com/google/go-cmp v0.5.6 // indirect
+	github.com/inconshreveable/mousetrap v1.0.0 // indirect
 	github.com/pkg/diff v0.0.0-20210226163009-20ebb0f2a09e // indirect
+	github.com/spf13/pflag v1.0.5 // indirect
 	golang.org/x/mod v0.5.1 // indirect
 	golang.org/x/xerrors v0.0.0-20200804184101-5ec99f83aff1 // indirect
 	gopkg.in/check.v1 v1.0.0-20190902080502-41f04d3bba15 // indirect

main.go

@@ -4,116 +4,136 @@ import (
 	"fmt"
 	"os"
 
-	"github.com/alecthomas/kingpin"
 	"github.com/gunk/gunk/convert"
 	"github.com/gunk/gunk/dump"
 	"github.com/gunk/gunk/format"
 	"github.com/gunk/gunk/generate"
 	"github.com/gunk/gunk/generate/downloader"
 	"github.com/gunk/gunk/log"
 	"github.com/gunk/gunk/vetconfig"
+	"github.com/spf13/cobra"
 )
 
-var (
-	version                 = "v0.8.7"
-	app                     = kingpin.New("gunk", "The modern frontend and syntax for Protocol Buffers.").UsageTemplate(kingpin.CompactUsageTemplate)
-	gen                     = app.Command("generate", "Generate code from Gunk packages.")
-	genPatterns             = gen.Arg("patterns", "patterns of Gunk packages").Strings()
-	conv                    = app.Command("convert", "Convert Proto file to Gunk file.")
-	convProtoFilesOrFolders = conv.Arg("files_or_folders", "Proto files or folders to convert to Gunk").Strings()
-	convOverwriteGunkFile   = conv.Flag("overwrite", "overwrite the converted Gunk file if it exists.").Bool()
-	frmt                    = app.Command("format", "Format Gunk code.")
-	frmtPatterns            = frmt.Arg("patterns", "patterns of Gunk packages").Strings()
-	dmp                     = app.Command("dump", "Write a FileDescriptorSet, defined in descriptor.proto")
-	dmpPatterns             = dmp.Arg("patterns", "patterns of Gunk packages").Strings()
-	dmpFormat               = dmp.Flag("format", "output format: proto (default), or json").String()
-	download                = app.Command("download", "Download required tools for Gunk, e.g., protoc")
-	dlAll                   = download.Command("all", "download all required tools")
-	dlProtoc                = download.Command("protoc", "download protoc")
-	dlProtocPath            = dlProtoc.Flag("path", "path to check for protoc binary, or where to download it to").String()
-	dlProtocVer             = dlProtoc.Flag("version", "version of protoc to use").String()
-	ver                     = app.Command("version", "Show Gunk version.")
-	vet                     = app.Command("vet", "Vet gunk config files")
-)
+var version = "v0.8.7"
 
 func main() {
-	os.Exit(main1())
-}
-
-func main1() (code int) {
-	// Replace kingpin's use of os.Exit, as testscript requires that we
-	// return exit codes instead of exiting the entire program. Use a panic,
-	// as we need to completely halt kingpin when it calls our terminate.
-	// But also make sure to not use `recover` and re-panic, as that does not print the correct
-	// stacktrace
-	var tCode int
-	var didTerminate bool
-	didPanic := true
-	app.Terminate(func(c int) {
-		didTerminate = true
-		tCode = c
-		panic("terminated")
-	})
-	defer func() {
-		if didPanic {
-			if didTerminate {
-				recover()
-				code = tCode
-			}
-		}
-	}()
-	c := main2()
-	didPanic = false
-	return c
+	os.Exit(run())
 }
 
-func main2() (code int) {
-	app.HelpFlag.Short('h') // allow -h as well as --help
-	gen.Flag("print-commands", "print the commands").Short('x').BoolVar(&log.PrintCommands)
-	gen.Flag("verbose", "print the names of packages as they are generated").Short('v').BoolVar(&log.Verbose)
-	download.Flag("verbose", "print details of downloaded tools").Short('v').BoolVar(&log.Verbose)
+func run() int {
+	app := cobra.Command{
+		Use:     "gunk",
+		Short:   "The modern frontend and syntax for Protocol Buffers.",
+		Version: version,
+	}
+	// version commmand
+	ver := &cobra.Command{
+		Use:   "version",
+		Short: "Print the version number of gundk",
+		Run: func(cmd *cobra.Command, args []string) {
+			fmt.Fprintln(os.Stdout, "gunk", version)
+		},
+	}
+	app.AddCommand(ver)
+	// generate command
+	gen := &cobra.Command{
+		Use:   "generate [patterns]",
+		Short: "Generate code from Gunk packages",
+		RunE: func(cmd *cobra.Command, args []string) error {
+			return generate.Run("", args...)
+		},
+	}
+	gen.Flags().BoolVarP(&log.PrintCommands, "print-commands", "x", false, "Print the commands")
+	gen.Flags().BoolVarP(&log.Verbose, "verbose", "v", false, "Print the names of packages are they are generated")
+	app.AddCommand(gen)
+	// convert command
+	var overwrite bool
+	conv := &cobra.Command{
+		Use:   "convert [-overwrite] [file | directory]...",
+		Short: "Convert Proto file to Gunk file.",
+		RunE: func(cmd *cobra.Command, args []string) error {
+			return convert.Run(args, overwrite)
+		},
+	}
+	conv.Flags().BoolVarP(&overwrite, "overwrite", "w", false, "Overwrite the converted Gunk file if it exists.")
+	// format command
+	app.AddCommand(conv)
+	frmt := &cobra.Command{
+		Use:   "format [patterns]",
+		Short: "Format Gunk code",
+		RunE: func(cmd *cobra.Command, args []string) error {
+			return format.Run("", args...)
+		},
+	}
+	app.AddCommand(frmt)
+	// dump command
+	var dmpFormat string
+	dmp := &cobra.Command{
+		Use:   "dump [patterns]",
+		Short: "Write a FileDescriptorSet, defined in descriptor.proto",
+		RunE: func(cmd *cobra.Command, args []string) error {
+			return dump.Run(dmpFormat, "", args...)
+		},
+	}
+	dmp.Flags().StringVarP(&dmpFormat, "format", "f", "proto", "output format: [proto | json]")
+	app.AddCommand(dmp)
+	// download list
+	// TODO(hhhapz): add protoc-java, and protoc-ts, etc.
 	downloadSubcommands := []func() error{
-		downloadProtoc,
+		func() error { return downloadProtoc("", "") },
 	}
-	command, err := app.Parse(os.Args[1:])
-	if code != 0 {
-		// simulate the os.Exit that would have happened
-		return code
-	} else if err != nil {
-		fmt.Fprintf(os.Stderr, "error: %v\n", err)
-		return 1
+	// download command
+	download := cobra.Command{
+		Use:   "download [protoc | protoc]",
+		Short: "Download the necessary tools for Gunk",
+	}
+	download.Flags().BoolVarP(&log.Verbose, "verbose", "v", false, "Print details of downloaded tools")
+	dlAll := cobra.Command{
+		Use:   "all",
+		Short: "Download all required tools for Gunk, e.g., protoc",
+		RunE: func(cmd *cobra.Command, args []string) error {
+			for _, f := range downloadSubcommands {
+				if err := f(); err != nil {
+					return err
+				}
+			}
+			return nil
+		},
+	}
+	var dlProtocPath, dlProtocVer string
+	dlProtoc := cobra.Command{
+		Use:   "protoc",
+		Short: "Download protoc",
+		RunE: func(cmd *cobra.Command, args []string) error {
+			return downloadProtoc(dlProtocPath, dlProtocVer)
+		},
 	}
-	switch command {
-	case ver.FullCommand():
-		fmt.Fprintf(os.Stdout, "gunk %s\n", version)
-	case gen.FullCommand():
-		err = generate.Run("", *genPatterns...)
-	case vet.FullCommand():
-		err = vetconfig.Run(".")
-	case conv.FullCommand():
-		err = convert.Run(*convProtoFilesOrFolders, *convOverwriteGunkFile)
-	case frmt.FullCommand():
-		err = format.Run("", *frmtPatterns...)
-	case dmp.FullCommand():
-		err = dump.Run(*dmpFormat, "", *dmpPatterns...)
-	case dlAll.FullCommand():
-		for _, dl := range downloadSubcommands {
-			err = dl()
-			if err != nil {
-				break
+	dlProtoc.Flags().StringVar(&dlProtocPath, "path", "", "Path to check for protoc binary, or where to download it to")
+	dlProtoc.Flags().BoolVarP(&log.Verbose, "verbose", "v", false, "Print details of download tools")
+	dlProtoc.Flags().StringVar(&dlProtocVer, "version", "", "Version of protoc to use")
+	download.AddCommand(&dlAll, &dlProtoc)
+	app.AddCommand(&download)
+	// vet command
+	vet := cobra.Command{
+		Use:   "vet [path]",
+		Short: "Vet gunk config files",
+		RunE: func(cmd *cobra.Command, args []string) error {
+			path := "."
+			if len(args) > 0 {
+				path = args[0]
 			}
-		}
-	case dlProtoc.FullCommand():
-		err = downloadProtoc()
+			return vetconfig.Run(path)
+		},
 	}
-	if err != nil {
-		fmt.Fprintf(os.Stderr, "error: %v\n", err)
+	app.AddCommand(&vet)
+	// run app
+	if err := app.Execute(); err != nil {
 		return 1
 	}
 	return 0
 }
 
-func downloadProtoc() error {
-	_, err := downloader.CheckOrDownloadProtoc(*dlProtocPath, *dlProtocVer)
+func downloadProtoc(path, version string) error {
+	_, err := downloader.CheckOrDownloadProtoc(path, version)
 	return err
 }

main_test.go

@@ -40,7 +40,7 @@ func TestMain(m *testing.M) {
 		}
 	}
 	os.Exit(testscript.RunMain(m, map[string]func() int{
-		"gunk": main1,
+		"gunk": run,
 	}))
 }
 

testdata/scripts/cmds.txt

@@ -1,43 +1,43 @@
 gunk
-stderr '^usage: gunk \['
-! stderr 'command not specified'
-! stdout .
+stdout 'Usage:\n  gunk \[command\]'
+! stdout 'command not specified'
+! stderr .
 
 gunk version
 stdout '^gunk v0.*'
 ! stderr .
 
 gunk -h
-stderr -count=1 '^usage: gunk \['
-! stdout .
+stdout 'Usage:\n  gunk \[command\]'
+! stderr .
 
 gunk --help
-stderr '^usage: gunk \['
-! stdout .
+stdout 'Usage:\n  gunk \[command\]'
+! stderr .
 
 gunk help
-stderr '^usage: gunk \['
-! stdout .
+stdout 'Usage:\n  gunk \[command\]'
+! stderr .
 
 gunk help generate
-stderr '^usage: gunk generate'
-! stdout .
+stdout 'Usage:\n  gunk generate \[patterns\] \[flags\]'
+! stderr .
 
-! gunk help missing
-stderr 'expected command'
+gunk help missing
+stderr 'Unknown help topic \[`missing`\]'
 
 ! gunk missing
-stderr 'expected command'
+stderr 'unknown command "missing"'
 
 gunk generate -h
-stderr '^usage: gunk generate'
-! stdout .
+stdout 'Usage:\n  gunk generate \[patterns\] \[flags\]'
+! stderr .
 
 gunk generate --help
-stderr '^usage: gunk generate'
-! stdout .
+stdout 'Usage:\n  gunk generate \[patterns\] \[flags\]'
+! stderr .
 
 ! gunk generate --missing
-stderr 'unknown long flag'
+stderr 'unknown flag: --missing'
 ! stdout .
 

testdata/scripts/convert_duplicates.txt

@@ -2,7 +2,7 @@ gunk convert util.proto
 cmp util.gunk util.gunk.golden
 
 ! gunk convert util2.proto
-stderr 'error: util2.proto:13:1: Event_Source redeclared in this block'
+stderr 'Error: util2.proto:13:1: Event_Source redeclared in this block'
 
 gunk convert util3.proto
 cmp util3.gunk util3.gunk.golden
@@ -89,4 +89,4 @@ const (
 )
 
 type Bar struct {
-}
+}

testdata/scripts/convert_errors.txt

@@ -1,5 +1,5 @@
 ! gunk convert util.proto
-stderr 'error: util.proto:5:1: "hello" is an unhandled proto file option'
+stderr 'Error: util.proto:5:1: "hello" is an unhandled proto file option'
 
 -- util.proto --
 syntax = "proto3";

testdata/scripts/convert_import_missing_gopkg.txt

@@ -1,5 +1,5 @@
 ! gunk convert util.proto
-stderr 'error: imported file must contain go_package option imported/imported.proto'
+stderr 'Error: imported file must contain go_package option imported/imported.proto'
 
 -- .gunkconfig --
 
@@ -41,4 +41,4 @@ package imported;
 
 message Type {
 	string Name = 1;
-}
+}

testdata/scripts/convert_import_no_gunkconfig.txt

@@ -1,5 +1,5 @@
 ! gunk convert util.proto
-stderr 'error: util.proto:9:2: imported.Type is undefined'
+stderr 'Error: util.proto:9:2: imported.Type is undefined'
 
 -- util.proto --
 syntax = "proto3";
@@ -41,4 +41,4 @@ option go_package= "github.com/gunk/gunk/imported";
 
 message Type {
 	string Name = 1;
-}
+}

testdata/scripts/repeated_function_param.txt

@@ -1,8 +1,8 @@
 ! gunk generate ./p1
-stderr 'error: .*p1/p1.gunk:9:2: parameter type should not be repeated'
+stderr 'Error: .*p1/p1.gunk:9:2: parameter type should not be repeated'
 
 ! gunk generate ./p2
-stderr 'error: .*p2/p2.gunk:9:2: parameter type should not be repeated'
+stderr 'Error: .*p2/p2.gunk:9:2: parameter type should not be repeated'
 
 -- go.mod --
 module testdata.tld/util