plumbing/transport: allow AdvertisedReferences being called multiple times. (#165)

* AdvertisedReferences is now part of transport.Session.
* It is allowed to be called more than once.
* It is allowed to be called before and after FetchPack/SendPack.
* Implementations cache its result.

2 files changed, 5 insertions, 5 deletions

diff --git a/plumbing/transport/http/common.go b/plumbing/transport/http/common.go
index a1b085b..aa3425e 100644
--- a/plumbing/transport/http/common.go
+++ b/plumbing/transport/http/common.go
@@ -6,6 +6,7 @@ import (
 	"net/http"
 
 	"gopkg.in/src-d/go-git.v4/plumbing"
+	"gopkg.in/src-d/go-git.v4/plumbing/protocol/packp"
 	"gopkg.in/src-d/go-git.v4/plumbing/transport"
 )
 
@@ -50,6 +51,7 @@ type session struct {
 	auth     AuthMethod
 	client   *http.Client
 	endpoint transport.Endpoint
+	advRefs  *packp.AdvRefs
 }
 
 func (s *session) SetAuth(auth transport.AuthMethod) error {
diff --git a/plumbing/transport/http/fetch_pack.go b/plumbing/transport/http/fetch_pack.go
index 1548110..0c85be4 100644
--- a/plumbing/transport/http/fetch_pack.go
+++ b/plumbing/transport/http/fetch_pack.go
@@ -17,7 +17,6 @@ import (
 
 type fetchPackSession struct {
 	*session
-	advRefsRun bool
 }
 
 func newFetchPackSession(c *http.Client,
@@ -33,12 +32,10 @@ func newFetchPackSession(c *http.Client,
 }
 
 func (s *fetchPackSession) AdvertisedReferences() (*packp.AdvRefs, error) {
-	if s.advRefsRun {
-		return nil, transport.ErrAdvertistedReferencesAlreadyCalled
+	if s.advRefs != nil {
+		return s.advRefs, nil
 	}
 
-	defer func() { s.advRefsRun = true }()
-
 	url := fmt.Sprintf(
 		"%s/info/refs?service=%s",
 		s.endpoint.String(), transport.UploadPackServiceName,
@@ -72,6 +69,7 @@ func (s *fetchPackSession) AdvertisedReferences() (*packp.AdvRefs, error) {
 	}
 
 	transport.FilterUnsupportedCapabilities(ar.Capabilities)
+	s.advRefs = ar
 	return ar, nil
 }