add unregister command

cmd/mg/cmd/register.go

@@ -20,6 +20,9 @@ var registerCmd = &cobra.Command{
 		}
 		if len(args) == 1 {
 			path = args[0]
+		} else if len(args) > 1 {
+			log.Println("too many arguments")
+			os.Exit(1)
 		}
 		r, err := git.PlainOpenWithOptions(path, &(git.PlainOpenOptions{DetectDotGit: true}))
 		if err != nil {

cmd/mg/cmd/unregister.go

@@ -1,17 +1,57 @@
 package cmd
 
 import (
-	"fmt"
+	"log"
+	"os"
 
+	git "github.com/go-git/go-git/v5"
 	"github.com/spf13/cobra"
 )
 
 // unregisterCmd represents the unregister command
 var unregisterCmd = &cobra.Command{
 	Use:   "unregister",
-	Short: "remove the current repo from the config",
-	Run: func(cmd *cobra.Command, args []string) {
-		fmt.Println("unregister called")
+	Short: "add current path to list of repos",
+	Run: func(_ *cobra.Command, args []string) {
+		conf := GetConfig()
+		path, err := os.Getwd()
+		if err != nil {
+			log.Println(err)
+			os.Exit(1)
+		}
+		if len(args) == 1 {
+			path = args[0]
+			err = conf.DelRepo(path)
+			if err != nil {
+				log.Println(err)
+				os.Exit(1)
+			}
+			return
+		} else if len(args) > 1 {
+			log.Println("too many arguments")
+			os.Exit(1)
+		}
+		r, err := git.PlainOpenWithOptions(path, &(git.PlainOpenOptions{DetectDotGit: true}))
+		if err != nil {
+			log.Println(err)
+			os.Exit(1)
+		}
+		newPath, err := r.Worktree()
+		if err != nil {
+			log.Println(err)
+			os.Exit(1)
+		}
+		path = newPath.Filesystem.Root()
+		err = conf.DelRepo(path)
+		if err != nil {
+			log.Println(err)
+			os.Exit(1)
+		}
+		err = conf.Save()
+		if err != nil {
+			log.Println(err)
+			os.Exit(1)
+		}
 	},
 }