remote: add support for ls-remote

options.go

@@ -348,3 +348,9 @@ func (o *CommitOptions) Validate(r *Repository) error {
 
 	return nil
 }
+
+// ListOptions describes how a remote list should be performed.
+type ListOptions struct {
+	// Auth credentials, if required, to use with the remote repository.
+	Auth transport.AuthMethod
+}

remote.go

@@ -728,6 +728,39 @@ func (r *Remote) buildFetchedTags(refs memory.ReferenceStorage) (updated bool, e
 	return
 }
 
+// List the references on the remote repository.
+func (r *Remote) List(o *ListOptions) ([]*plumbing.Reference, error) {
+	s, err := newUploadPackSession(r.c.URLs[0], o.Auth)
+	if err != nil {
+		return nil, err
+	}
+
+	defer ioutil.CheckClose(s, &err)
+
+	ar, err := s.AdvertisedReferences()
+	if err != nil {
+		return nil, err
+	}
+
+	allRefs, err := ar.AllReferences()
+	if err != nil {
+		return nil, err
+	}
+
+	refs, err := allRefs.IterReferences()
+	if err != nil {
+		return nil, err
+	}
+
+	var resultRefs []*plumbing.Reference
+	refs.ForEach(func(ref *plumbing.Reference) error {
+		resultRefs = append(resultRefs, ref)
+		return nil
+	})
+
+	return resultRefs, nil
+}
+
 func objectsToPush(commands []*packp.Command) ([]plumbing.Hash, error) {
 	var objects []plumbing.Hash
 	for _, cmd := range commands {

remote_test.go

@@ -642,3 +642,34 @@ func (s *RemoteSuite) TestGetHaves(c *C) {
 	c.Assert(err, IsNil)
 	c.Assert(l, HasLen, 2)
 }
+
+func (s *RemoteSuite) TestList(c *C) {
+	repo := fixtures.Basic().One()
+	remote := newRemote(memory.NewStorage(), &config.RemoteConfig{
+		Name: DefaultRemoteName,
+		URLs: []string{repo.URL},
+	})
+
+	refs, err := remote.List(&ListOptions{})
+	c.Assert(err, IsNil)
+
+	expected := []*plumbing.Reference{
+		plumbing.NewSymbolicReference("HEAD", "refs/heads/master"),
+		plumbing.NewReferenceFromStrings("refs/heads/master", "6ecf0ef2c2dffb796033e5a02219af86ec6584e5"),
+		plumbing.NewReferenceFromStrings("refs/heads/branch", "e8d3ffab552895c19b9fcf7aa264d277cde33881"),
+		plumbing.NewReferenceFromStrings("refs/pull/1/head", "b8e471f58bcbca63b07bda20e428190409c2db47"),
+		plumbing.NewReferenceFromStrings("refs/pull/2/head", "9632f02833b2f9613afb5e75682132b0b22e4a31"),
+		plumbing.NewReferenceFromStrings("refs/pull/2/merge", "c37f58a130ca555e42ff96a071cb9ccb3f437504"),
+	}
+	c.Assert(len(refs), Equals, len(expected))
+	for _, e := range expected {
+		found := false
+		for _, r := range refs {
+			if r.Name() == e.Name() {
+				found = true
+				c.Assert(r, DeepEquals, e)
+			}
+		}
+		c.Assert(found, Equals, true)
+	}
+}