submodule init and update implementation

1 files changed, 57 insertions, 11 deletions

diff --git a/submodule.go b/submodule.go
index ea099f0..83c28b7 100644
--- a/submodule.go
+++ b/submodule.go
@@ -1,33 +1,79 @@
 package git
 
 import (
-	"fmt"
-
+	"srcd.works/go-git.v4/config"
 	"srcd.works/go-git.v4/plumbing"
 )
 
+// Submodule a submodule allows you to keep another Git repository in a
+// subdirectory of your repository.
 type Submodule struct {
-	Name   string
-	Branch string
-	URL    string
-
+	m *config.Submodule
+	w *Worktree
+	// r is the submodule repository
 	r *Repository
 }
 
+// Config returns the submodule config
+func (s *Submodule) Config() *config.Submodule {
+	return s.m
+}
+
+// Init initialize the submodule reading the recoreded Entry in the index for
+// the given submodule
 func (s *Submodule) Init() error {
-	return s.r.clone(&CloneOptions{
-		URL:           s.URL,
-		ReferenceName: plumbing.ReferenceName(s.Branch),
+	e, err := s.w.readIndexEntry(s.m.Path)
+	if err != nil {
+		return err
+	}
+
+	_, err = s.r.CreateRemote(&config.RemoteConfig{
+		Name: DefaultRemoteName,
+		URL:  s.m.URL,
 	})
+
+	if err != nil {
+		return err
+	}
+
+	return s.fetchAndCheckout(e.Hash)
+}
+
+// Update  the registered submodule to match what the superproject expects
+func (s *Submodule) Update() error {
+	e, err := s.w.readIndexEntry(s.m.Path)
+	if err != nil {
+		return err
+	}
+
+	return s.fetchAndCheckout(e.Hash)
+}
+
+func (s *Submodule) fetchAndCheckout(hash plumbing.Hash) error {
+	if err := s.r.Fetch(&FetchOptions{}); err != nil && err != NoErrAlreadyUpToDate {
+		return err
+	}
+
+	w, err := s.r.Worktree()
+	if err != nil {
+		return err
+	}
+
+	if err := w.Checkout(hash); err != nil {
+		return err
+	}
+
+	head := plumbing.NewHashReference(plumbing.HEAD, hash)
+	return s.r.Storer.SetReference(head)
 }
 
+// Submodules list of several submodules from the same repository
 type Submodules []*Submodule
 
+// Init initialize the submodule recorded in the index
 func (s Submodules) Init() error {
 	for _, sub := range s {
-		fmt.Println("clone", sub.URL)
 		if err := sub.Init(); err != nil {
-			fmt.Println(err)
 			return err
 		}
 	}