Remote.Clone fix clone of tags in shallow mode

repository.go

@@ -448,20 +448,24 @@ func (r *Repository) clone(ctx context.Context, o *CloneOptions) error {
 	return r.updateRemoteConfigIfNeeded(o, c, head)
 }
 
-func (r *Repository) cloneRefSpec(o *CloneOptions,
-	c *config.RemoteConfig) []config.RefSpec {
-
-	if !o.SingleBranch {
-		return c.Fetch
-	}
+const (
+	refspecTagWithDepth     = "+refs/tags/%s:refs/tags/%[1]s"
+	refspecSingleBranch     = "+refs/heads/%s:refs/remotes/%s/%[1]s"
+	refspecSingleBranchHEAD = "+HEAD:refs/remotes/%s/HEAD"
+)
 
+func (r *Repository) cloneRefSpec(o *CloneOptions, c *config.RemoteConfig) []config.RefSpec {
 	var rs string
 
-	if o.ReferenceName == plumbing.HEAD {
+	switch {
+	case o.ReferenceName.IsTag() && o.Depth > 0:
+		rs = fmt.Sprintf(refspecTagWithDepth, o.ReferenceName.Short())
+	case o.SingleBranch && o.ReferenceName == plumbing.HEAD:
 		rs = fmt.Sprintf(refspecSingleBranchHEAD, c.Name)
-	} else {
-		rs = fmt.Sprintf(refspecSingleBranch,
-			o.ReferenceName.Short(), c.Name)
+	case o.SingleBranch:
+		rs = fmt.Sprintf(refspecSingleBranch, o.ReferenceName.Short(), c.Name)
+	default:
+		return c.Fetch
 	}
 
 	return []config.RefSpec{config.RefSpec(rs)}
@@ -477,11 +481,6 @@ func (r *Repository) setIsBare(isBare bool) error {
 	return r.Storer.SetConfig(cfg)
 }
 
-const (
-	refspecSingleBranch     = "+refs/heads/%s:refs/remotes/%s/%[1]s"
-	refspecSingleBranchHEAD = "+HEAD:refs/remotes/%s/HEAD"
-)
-
 func (r *Repository) updateRemoteConfigIfNeeded(o *CloneOptions, c *config.RemoteConfig, head *plumbing.Reference) error {
 	if !o.SingleBranch {
 		return nil

repository_test.go

@@ -613,12 +613,42 @@ func (s *RepositorySuite) TestCloneDetachedHEAD(c *C) {
 		URL:           s.GetBasicLocalRepositoryURL(),
 		ReferenceName: plumbing.ReferenceName("refs/tags/v1.0.0"),
 	})
+	c.Assert(err, IsNil)
+
+	head, err := r.Reference(plumbing.HEAD, false)
+	c.Assert(err, IsNil)
+	c.Assert(head, NotNil)
+	c.Assert(head.Type(), Equals, plumbing.HashReference)
+	c.Assert(head.Hash().String(), Equals, "6ecf0ef2c2dffb796033e5a02219af86ec6584e5")
+
+	count := 0
+	objects, err := r.Objects()
+	c.Assert(err, IsNil)
+	objects.ForEach(func(object.Object) error { count++; return nil })
+	c.Assert(count, Equals, 31)
+}
+
+func (s *RepositorySuite) TestCloneDetachedHEADAndShallow(c *C) {
+	r, _ := Init(memory.NewStorage(), memfs.New())
+	err := r.clone(context.Background(), &CloneOptions{
+		URL:           s.GetBasicLocalRepositoryURL(),
+		ReferenceName: plumbing.ReferenceName("refs/tags/v1.0.0"),
+		Depth:         1,
+	})
+
+	c.Assert(err, IsNil)
 
 	head, err := r.Reference(plumbing.HEAD, false)
 	c.Assert(err, IsNil)
 	c.Assert(head, NotNil)
 	c.Assert(head.Type(), Equals, plumbing.HashReference)
 	c.Assert(head.Hash().String(), Equals, "6ecf0ef2c2dffb796033e5a02219af86ec6584e5")
+
+	count := 0
+	objects, err := r.Objects()
+	c.Assert(err, IsNil)
+	objects.ForEach(func(object.Object) error { count++; return nil })
+	c.Assert(count, Equals, 15)
 }
 
 func (s *RepositorySuite) TestPush(c *C) {