plumbing: transport, fix handling of empty adv-refs on upload-pack

2 files changed, 23 insertions, 9 deletions

diff --git a/plumbing/protocol/packp/advrefs.go b/plumbing/protocol/packp/advrefs.go
index ab286c6..1bd724c 100644
--- a/plumbing/protocol/packp/advrefs.go
+++ b/plumbing/protocol/packp/advrefs.go
@@ -201,3 +201,11 @@ func (a *AdvRefs) addSymbolicRefs(s storer.ReferenceStorer) error {
 func (a *AdvRefs) supportSymrefs() bool {
 	return a.Capabilities.Supports(capability.SymRef)
 }
+
+// IsEmpty returns true if doesn't contain any reference.
+func (a *AdvRefs) IsEmpty() bool {
+	return a.Head == nil &&
+		len(a.References) == 0 &&
+		len(a.Peeled) == 0 &&
+		len(a.Shallows) == 0
+}
diff --git a/plumbing/protocol/packp/advrefs_test.go b/plumbing/protocol/packp/advrefs_test.go
index d37f127..d163e1f 100644
--- a/plumbing/protocol/packp/advrefs_test.go
+++ b/plumbing/protocol/packp/advrefs_test.go
@@ -79,6 +79,11 @@ func (s *AdvRefSuite) TestAllReferencesBadSymref(c *C) {
 	c.Assert(err, NotNil)
 }
 
+func (s *AdvRefSuite) TestIsEmpty(c *C) {
+	a := NewAdvRefs()
+	c.Assert(a.IsEmpty(), Equals, true)
+}
+
 func (s *AdvRefSuite) TestNoSymRefCapabilityHeadToMaster(c *C) {
 	a := NewAdvRefs()
 	headHash := plumbing.NewHash("5dc01c595e6c6ec9ccda4f6f69c131c0dd945f8c")
@@ -156,7 +161,7 @@ type AdvRefsDecodeEncodeSuite struct{}
 
 var _ = Suite(&AdvRefsDecodeEncodeSuite{})
 
-func (s *AdvRefsDecodeEncodeSuite) test(c *C, in []string, exp []string) {
+func (s *AdvRefsDecodeEncodeSuite) test(c *C, in []string, exp []string, isEmpty bool) {
 	var err error
 	var input io.Reader
 	{
@@ -181,6 +186,7 @@ func (s *AdvRefsDecodeEncodeSuite) test(c *C, in []string, exp []string) {
 	{
 		ar := NewAdvRefs()
 		c.Assert(ar.Decode(input), IsNil)
+		c.Assert(ar.IsEmpty(), Equals, isEmpty)
 
 		var buf bytes.Buffer
 		c.Assert(ar.Encode(&buf), IsNil)
@@ -202,7 +208,7 @@ func (s *AdvRefsDecodeEncodeSuite) TestNoHead(c *C) {
 		pktline.FlushString,
 	}
 
-	s.test(c, input, expected)
+	s.test(c, input, expected, true)
 }
 
 func (s *AdvRefsDecodeEncodeSuite) TestNoHeadSmart(c *C) {
@@ -218,7 +224,7 @@ func (s *AdvRefsDecodeEncodeSuite) TestNoHeadSmart(c *C) {
 		pktline.FlushString,
 	}
 
-	s.test(c, input, expected)
+	s.test(c, input, expected, true)
 }
 
 func (s *AdvRefsDecodeEncodeSuite) TestNoHeadSmartBug(c *C) {
@@ -236,7 +242,7 @@ func (s *AdvRefsDecodeEncodeSuite) TestNoHeadSmartBug(c *C) {
 		pktline.FlushString,
 	}
 
-	s.test(c, input, expected)
+	s.test(c, input, expected, true)
 }
 
 func (s *AdvRefsDecodeEncodeSuite) TestRefs(c *C) {
@@ -256,7 +262,7 @@ func (s *AdvRefsDecodeEncodeSuite) TestRefs(c *C) {
 		pktline.FlushString,
 	}
 
-	s.test(c, input, expected)
+	s.test(c, input, expected, false)
 }
 
 func (s *AdvRefsDecodeEncodeSuite) TestPeeled(c *C) {
@@ -280,7 +286,7 @@ func (s *AdvRefsDecodeEncodeSuite) TestPeeled(c *C) {
 		pktline.FlushString,
 	}
 
-	s.test(c, input, expected)
+	s.test(c, input, expected, false)
 }
 
 func (s *AdvRefsDecodeEncodeSuite) TestAll(c *C) {
@@ -308,7 +314,7 @@ func (s *AdvRefsDecodeEncodeSuite) TestAll(c *C) {
 		pktline.FlushString,
 	}
 
-	s.test(c, input, expected)
+	s.test(c, input, expected, false)
 }
 
 func (s *AdvRefsDecodeEncodeSuite) TestAllSmart(c *C) {
@@ -340,7 +346,7 @@ func (s *AdvRefsDecodeEncodeSuite) TestAllSmart(c *C) {
 		pktline.FlushString,
 	}
 
-	s.test(c, input, expected)
+	s.test(c, input, expected, false)
 }
 
 func (s *AdvRefsDecodeEncodeSuite) TestAllSmartBug(c *C) {
@@ -372,7 +378,7 @@ func (s *AdvRefsDecodeEncodeSuite) TestAllSmartBug(c *C) {
 		pktline.FlushString,
 	}
 
-	s.test(c, input, expected)
+	s.test(c, input, expected, false)
 }
 
 func ExampleAdvRefs_Decode() {