.zsh_history merge+remove duplicate lines

main.go

package main

import (
	"fmt"
	"io/ioutil"
	"os"
	"regexp"
	"sort"
	"strconv"
	"strings"

	"github.com/MendelGusmao/smart"
)

var lineRE = regexp.MustCompile(`: (\d+):\d+;.*`)

type Command struct {
	ts   int
	line string
}

func (c Command) escape() string {
	if strings.Contains(c.line, "\n") {
		return strings.Replace(c.line, "\n", "\\\n", -1)
	}

	return c.line
}

type History []Command

func (h History) Len() int           { return len(h) }
func (h History) Swap(i, j int)      { h[i], h[j] = h[j], h[i] }
func (h History) Less(i, j int) bool { return h[i].ts < h[j].ts }

func main() {
	commands := make(map[string]Command)
	args := os.Args[1:]

	if len(args) < 2 {
		fmt.Println("You need to provide at least 2 arguments")
		os.Exit(1)
	}

	for _, file := range args {
		content, err := ioutil.ReadFile(file)

		if err != nil {
			fmt.Println(err)
			os.Exit(1)
		}

		for _, s := range smart.Split(string(content), "\n", "\\") {
			if lineRE.MatchString(s) {
				ts, err := strconv.Atoi(lineRE.FindStringSubmatch(s)[1])

				if err != nil {
					fmt.Println("Timestamp error @", s)
					os.Exit(1)
				}

				if _, ok := commands[s]; ok {
					continue
				}

				commands[s] = Command{ts, s}
			} else {
				fmt.Println("Error @", s)
				os.Exit(1)
			}
		}
	}

	history := make(History, 0)

	for _, command := range commands {
		history = append(history, command)
	}

	sort.Sort(history)

	for _, command := range history {
		fmt.Println(command.escape())
	}
}

go run main.go .zsh_history_1 .zsh_history_2 .zsh_history_N... > .zsh_history_new