Switch to cobra and allow cli aliases

Signed-off-by: Sascha Grunert <sgrunert@redhat.com>

.golangci.yml

@@ -114,6 +114,11 @@ linters:
     # - varnamelen
     # - wsl
 linters-settings:
+  gci:
+    sections:
+      - standard
+      - default
+      - localmodule
   cyclop:
     max-complexity: 15
   godox:

go.mod

@@ -5,6 +5,7 @@ go 1.22
 require (
 	github.com/gomarkdown/markdown v0.0.0-20240328165702-4d01890c35c0
 	github.com/mmarkdown/mmark v2.0.40+incompatible
+	github.com/spf13/cobra v1.8.1
 	github.com/stretchr/testify v1.9.0
 	sigs.k8s.io/release-utils v0.8.3
 )
@@ -15,7 +16,6 @@ require (
 	github.com/davecgh/go-spew v1.1.1 // indirect
 	github.com/inconshreveable/mousetrap v1.1.0 // indirect
 	github.com/pmezard/go-difflib v1.0.0 // indirect
-	github.com/spf13/cobra v1.8.1 // indirect
 	github.com/spf13/pflag v1.0.5 // indirect
 	gopkg.in/yaml.v3 v3.0.1 // indirect
 )

mdtoc.go

@@ -18,15 +18,24 @@ package main
 
 import (
 	"errors"
-	"flag"
 	"fmt"
 	"log"
 	"os"
 
-	"sigs.k8s.io/mdtoc/pkg/mdtoc"
+	"github.com/spf13/cobra"
 	"sigs.k8s.io/release-utils/version"
+
+	"sigs.k8s.io/mdtoc/pkg/mdtoc"
 )
 
+var cmd = &cobra.Command{
+	Use: os.Args[0] + " [FILE]...",
+	Long: "Generate a table of contents for a markdown file (GitHub flavor).\n\n" +
+		"TOC may be wrapped in a pair of tags to allow in-place updates:\n" +
+		"<!-- toc --><!-- /toc -->",
+	RunE: run,
+}
+
 type utilityOptions struct {
 	mdtoc.Options
 	Inplace bool
@@ -35,59 +44,51 @@ type utilityOptions struct {
 var defaultOptions utilityOptions
 
 func init() {
-	flag.BoolVar(&defaultOptions.Dryrun, "dryrun", false, "Whether to check for changes to TOC, rather than overwriting. Requires --inplace flag.")
-	flag.BoolVar(&defaultOptions.Inplace, "inplace", false, "Whether to edit the file in-place, or output to STDOUT. Requires toc tags to be present.")
-	flag.BoolVar(&defaultOptions.SkipPrefix, "skip-prefix", true, "Whether to ignore any headers before the opening toc tag.")
-	flag.IntVar(&defaultOptions.MaxDepth, "max-depth", mdtoc.MaxHeaderDepth, "Limit the depth of headers that will be included in the TOC.")
-	flag.BoolVar(&defaultOptions.Version, "version", false, "Show MDTOC version.")
-
-	flag.Usage = func() {
-		fmt.Fprintf(flag.CommandLine.Output(), "Usage: %s [OPTIONS] [FILE]...\n", os.Args[0])
-		fmt.Fprintf(flag.CommandLine.Output(), "Generate a table of contents for a markdown file (github flavor).\n")
-		fmt.Fprintf(flag.CommandLine.Output(), "TOC may be wrapped in a pair of tags to allow in-place updates: <!-- toc --><!-- /toc -->\n")
-		flag.PrintDefaults()
-	}
+	cmd.PersistentFlags().BoolVarP(&defaultOptions.Dryrun, "dryrun", "d", false, "Whether to check for changes to TOC, rather than overwriting. Requires --inplace flag.")
+	cmd.PersistentFlags().BoolVarP(&defaultOptions.Inplace, "inplace", "i", false, "Whether to edit the file in-place, or output to STDOUT. Requires toc tags to be present.")
+	cmd.PersistentFlags().BoolVarP(&defaultOptions.SkipPrefix, "skip-prefix", "s", true, "Whether to ignore any headers before the opening toc tag.")
+	cmd.PersistentFlags().IntVarP(&defaultOptions.MaxDepth, "max-depth", "m", mdtoc.MaxHeaderDepth, "Limit the depth of headers that will be included in the TOC.")
+	cmd.PersistentFlags().BoolVarP(&defaultOptions.Version, "version", "v", false, "Show MDTOC version.")
 }
 
 func main() {
-	flag.Parse()
+	if err := cmd.Execute(); err != nil {
+		log.Fatal(err)
+	}
+}
 
+func run(_ *cobra.Command, args []string) error {
 	if defaultOptions.Version {
 		v := version.GetVersionInfo()
 		v.Name = "mdtoc"
 		v.Description = "is a utility for generating a table-of-contents for markdown files"
 		v.ASCIIName = "true"
 		v.FontName = "banner"
 		fmt.Fprintln(os.Stdout, v.String())
-		os.Exit(0)
+		return nil
 	}
 
-	if err := validateArgs(defaultOptions, flag.Args()); err != nil {
-		fmt.Fprintf(os.Stderr, "Error: %v\n", err)
-		flag.Usage()
-		os.Exit(1)
+	if err := validateArgs(defaultOptions, args); err != nil {
+		return fmt.Errorf("validate args: %w", err)
 	}
 
-	switch defaultOptions.Inplace {
-	case true:
-		hadError := false
-		for _, file := range flag.Args() {
-			err := mdtoc.WriteTOC(file, defaultOptions.Options)
-			if err != nil {
-				log.Printf("%s: %v", file, err)
-				hadError = true
+	if defaultOptions.Inplace {
+		var retErr error
+		for _, file := range args {
+			if err := mdtoc.WriteTOC(file, defaultOptions.Options); err != nil {
+				retErr = errors.Join(retErr, fmt.Errorf("%s: %w", file, err))
 			}
 		}
-		if hadError {
-			os.Exit(1)
-		}
-	case false:
-		toc, err := mdtoc.GetTOC(flag.Args()[0], defaultOptions.Options)
-		if err != nil {
-			os.Exit(1)
-		}
-		fmt.Println(toc)
+		return retErr
 	}
+
+	toc, err := mdtoc.GetTOC(args[0], defaultOptions.Options)
+	if err != nil {
+		return fmt.Errorf("get toc: %w", err)
+	}
+	fmt.Println(toc)
+
+	return nil
 }
 
 func validateArgs(opts utilityOptions, args []string) error {

mdtoc_test.go

@@ -24,6 +24,7 @@ import (
 
 	"github.com/stretchr/testify/assert"
 	"github.com/stretchr/testify/require"
+
 	"sigs.k8s.io/mdtoc/pkg/mdtoc"
 )