replace dbg: as dbg:<line_number>

patchdbg

package main

import (
	"flag"
	"fmt"
	"io/ioutil"
	"log"
	"os"
	"path"
	"regexp"
	"strings"
)

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

func usage() {
	fmt.Fprintln(os.Stderr, "Usage:", path.Base(os.Args[0]), "<file>")
	flag.PrintDefaults()
	os.Exit(1)
}

var re = regexp.MustCompile(`^(.*dbg:)([0-9]+)(.*)$`)

func main() {
	log.SetFlags(log.Lshortfile)
	flag.Usage = usage
	flag.Parse()
	if flag.NArg() != 1 {
		usage()
	}
	updated := false
	filename := flag.Arg(0)
	input, err := ioutil.ReadFile(filename)
	check(err)
	lines := strings.Split(string(input), "\n")
	for i, line := range lines {
		newline := re.ReplaceAllString(line, fmt.Sprintf(`${1}%d$3`, i+1))
		if newline != line {
			lines[i] = newline
			updated = true
		}
	}
	if updated {
		fi, err := os.Lstat(filename)
		check(err)
		fmt.Printf("permissions: %#o\n", fi.Mode().Perm())
		output := strings.Join(lines, "\n")
		err = ioutil.WriteFile(filename, []byte(output), fi.Mode().Perm())
		check(err)
		fmt.Println("patched", filename)
	} else {
		fmt.Println("skip", filename)
	}
}