1 files changed, 91 insertions, 4 deletions

diff --git a/remote.go b/remote.go
index 4a06106..9f2995d 100644
--- a/remote.go
+++ b/remote.go
@@ -5,10 +5,12 @@ import (
 	"errors"
 	"fmt"
 	"io"
+	"strings"
 	"time"
 
 	"github.com/go-git/go-billy/v5/osfs"
 	"github.com/go-git/go-git/v5/config"
+	"github.com/go-git/go-git/v5/internal/url"
 	"github.com/go-git/go-git/v5/plumbing"
 	"github.com/go-git/go-git/v5/plumbing/cache"
 	"github.com/go-git/go-git/v5/plumbing/format/packfile"
@@ -103,7 +105,11 @@ func (r *Remote) PushContext(ctx context.Context, o *PushOptions) (err error) {
 		return fmt.Errorf("remote names don't match: %s != %s", o.RemoteName, r.c.Name)
 	}
 
-	s, err := newSendPackSession(r.c.URLs[0], o.Auth, o.InsecureSkipTLS, o.CABundle)
+	if o.RemoteURL == "" {
+		o.RemoteURL = r.c.URLs[0]
+	}
+
+	s, err := newSendPackSession(o.RemoteURL, o.Auth, o.InsecureSkipTLS, o.CABundle)
 	if err != nil {
 		return err
 	}
@@ -183,12 +189,12 @@ func (r *Remote) PushContext(ctx context.Context, o *PushOptions) (err error) {
 	var hashesToPush []plumbing.Hash
 	// Avoid the expensive revlist operation if we're only doing deletes.
 	if !allDelete {
-		if r.c.IsFirstURLLocal() {
+		if url.IsLocalEndpoint(o.RemoteURL) {
 			// If we're are pushing to a local repo, it might be much
 			// faster to use a local storage layer to get the commits
 			// to ignore, when calculating the object revlist.
 			localStorer := filesystem.NewStorage(
-				osfs.New(r.c.URLs[0]), cache.NewObjectLRUDefault())
+				osfs.New(o.RemoteURL), cache.NewObjectLRUDefault())
 			hashesToPush, err = revlist.ObjectsWithStorageForIgnores(
 				r.s, localStorer, objects, haves)
 		} else {
@@ -225,6 +231,77 @@ func (r *Remote) useRefDeltas(ar *packp.AdvRefs) bool {
 	return !ar.Capabilities.Supports(capability.OFSDelta)
 }
 
+func (r *Remote) addReachableTags(localRefs []*plumbing.Reference, remoteRefs storer.ReferenceStorer, req *packp.ReferenceUpdateRequest) error {
+	tags := make(map[plumbing.Reference]struct{})
+	// get a list of all tags locally
+	for _, ref := range localRefs {
+		if strings.HasPrefix(string(ref.Name()), "refs/tags") {
+			tags[*ref] = struct{}{}
+		}
+	}
+
+	remoteRefIter, err := remoteRefs.IterReferences()
+	if err != nil {
+		return err
+	}
+
+	// remove any that are already on the remote
+	if err := remoteRefIter.ForEach(func(reference *plumbing.Reference) error {
+		if _, ok := tags[*reference]; ok {
+			delete(tags, *reference)
+		}
+
+		return nil
+	}); err != nil {
+		return err
+	}
+
+	for tag, _ := range tags {
+		tagObject, err := object.GetObject(r.s, tag.Hash())
+		var tagCommit *object.Commit
+		if err != nil {
+			return fmt.Errorf("get tag object: %w\n", err)
+		}
+
+		if tagObject.Type() != plumbing.TagObject {
+			continue
+		}
+
+		annotatedTag, ok := tagObject.(*object.Tag)
+		if !ok {
+			return errors.New("could not get annotated tag object")
+		}
+
+		tagCommit, err = object.GetCommit(r.s, annotatedTag.Target)
+		if err != nil {
+			return fmt.Errorf("get annotated tag commit: %w\n", err)
+		}
+
+		// only include tags that are reachable from one of the refs
+		// already being pushed
+		for _, cmd := range req.Commands {
+			if tag.Name() == cmd.Name {
+				continue
+			}
+
+			if strings.HasPrefix(cmd.Name.String(), "refs/tags") {
+				continue
+			}
+
+			c, err := object.GetCommit(r.s, cmd.New)
+			if err != nil {
+				return fmt.Errorf("get commit %v: %w", cmd.Name, err)
+			}
+
+			if isAncestor, err := tagCommit.IsAncestor(c); err == nil && isAncestor {
+				req.Commands = append(req.Commands, &packp.Command{Name: tag.Name(), New: tag.Hash()})
+			}
+		}
+	}
+
+	return nil
+}
+
 func (r *Remote) newReferenceUpdateRequest(
 	o *PushOptions,
 	localRefs []*plumbing.Reference,
@@ -246,6 +323,12 @@ func (r *Remote) newReferenceUpdateRequest(
 		return nil, err
 	}
 
+	if o.FollowTags {
+		if err := r.addReachableTags(localRefs, remoteRefs, req); err != nil {
+			return nil, err
+		}
+	}
+
 	return req, nil
 }
 
@@ -314,7 +397,11 @@ func (r *Remote) fetch(ctx context.Context, o *FetchOptions) (sto storer.Referen
 		o.RefSpecs = r.c.Fetch
 	}
 
-	s, err := newUploadPackSession(r.c.URLs[0], o.Auth, o.InsecureSkipTLS, o.CABundle)
+	if o.RemoteURL == "" {
+		o.RemoteURL = r.c.URLs[0]
+	}
+
+	s, err := newUploadPackSession(o.RemoteURL, o.Auth, o.InsecureSkipTLS, o.CABundle)
 	if err != nil {
 		return nil, err
 	}