examples: checkout example update

_examples/checkout/main.go

@@ -11,25 +11,37 @@ import (
 
 // Basic example of how to checkout a specific commit.
 func main() {
-	CheckArgs("<url>", "<directory>", "<commit-ref>")
-	url, directory, commitRef := os.Args[1], os.Args[2], os.Args[3]
+	CheckArgs("<url>", "<directory>", "<commit>")
+	url, directory, commit := os.Args[1], os.Args[2], os.Args[3]
 
 	// Clone the given repository to the given directory
 	Info("git clone %s %s", url, directory)
-
 	r, err := git.PlainClone(directory, false, &git.CloneOptions{
 		URL: url,
 	})
 
 	CheckIfError(err)
 
-	Info("git checkout %s", commitRef)
+	// ... retrieving the commit being pointed by HEAD
+	Info("git show-ref --head HEAD")
+	ref, err := r.Head()
+	CheckIfError(err)
+	fmt.Println(ref.Hash())
 
 	w, err := r.Worktree()
-
 	CheckIfError(err)
 
-	CheckIfError(w.Checkout(plumbing.NewHash(commitRef)))
+	// ... checking out to commit
+	Info("git checkout %s", commit)
+	err = w.Checkout(&git.CheckoutOptions{
+		Hash: plumbing.NewHash(commit),
+	})
+	CheckIfError(err)
 
-	fmt.Println("voila")
+	// ... retrieving the commit being pointed by HEAD, it's shows that the
+	// repository is poiting to the giving commit in detached mode
+	Info("git show-ref --head HEAD")
+	ref, err = r.Head()
+	CheckIfError(err)
+	fmt.Println(ref.Hash())
 }

_examples/common_test.go

@@ -13,7 +13,7 @@ import (
 
 var examplesTest = flag.Bool("examples", false, "run the examples tests")
 
-var defaultURL = "https://github.com/mcuadros/basic.git"
+var defaultURL = "https://github.com/git-fixtures/basic.git"
 
 var args = map[string][]string{
 	"checkout":    []string{defaultURL, tempFolder(), "35e85108805c84807bc66a02d91535e1e24b38b9"},