Add simple tests for SeekObjectHeader.

Signed-off-by: Filip Navara <[email protected]>

Author: filipnavara

plumbing/format/packfile/scanner.go

@@ -141,7 +141,7 @@ func (s *Scanner) readCount() (uint32, error) {
 // SeekObjectHeader seeks to specified offset and returns the ObjectHeader
 // for the next object in the reader
 func (s *Scanner) SeekObjectHeader(offset int64) (*ObjectHeader, error) {
-	// if seeking we assume that you are not interested on the header
+	// if seeking we assume that you are not interested in the header
 	if s.version == 0 {
 		s.version = VersionSupported
 	}
@@ -150,8 +150,8 @@ func (s *Scanner) SeekObjectHeader(offset int64) (*ObjectHeader, error) {
 		return nil, err
 	}
 
-	h, err := s.nextObjectHeader();
-	if  err != nil {
+	h, err := s.nextObjectHeader()
+	if err != nil {
 		return nil, err
 	}
 
@@ -165,13 +165,13 @@ func (s *Scanner) NextObjectHeader() (*ObjectHeader, error) {
 		return nil, err
 	}
 
-	offset, err := s.r.Seek(0, io.SeekCurrent);
-	if  err != nil {
+	offset, err := s.r.Seek(0, io.SeekCurrent)
+	if err != nil {
 		return nil, err
 	}
 
-	h, err := s.nextObjectHeader();
-	if  err != nil {
+	h, err := s.nextObjectHeader()
+	if err != nil {
 		return nil, err
 	}
 
@@ -346,7 +346,7 @@ var byteSlicePool = sync.Pool{
 // SeekFromStart sets a new offset from start, returns the old position before
 // the change.
 func (s *Scanner) SeekFromStart(offset int64) (previous int64, err error) {
-	// if seeking we assume that you are not interested on the header
+	// if seeking we assume that you are not interested in the header
 	if s.version == 0 {
 		s.version = VersionSupported
 	}

plumbing/format/packfile/scanner_test.go

@@ -118,6 +118,23 @@ func (s *ScannerSuite) TestNextObjectHeaderWithOutReadObjectNonSeekable(c *C) {
 	c.Assert(n, Equals, f.PackfileHash)
 }
 
+func (s *ScannerSuite) TestSeekObjectHeader(c *C) {
+	r := fixtures.Basic().One().Packfile()
+	p := NewScanner(r)
+
+	h, err := p.SeekObjectHeader(expectedHeadersOFS[4].Offset)
+	c.Assert(err, IsNil)
+	c.Assert(h, DeepEquals, &expectedHeadersOFS[4])
+}
+
+func (s *ScannerSuite) TestSeekObjectHeaderNonSeekable(c *C) {
+	r := io.MultiReader(fixtures.Basic().One().Packfile())
+	p := NewScanner(r)
+
+	_, err := p.SeekObjectHeader(expectedHeadersOFS[4].Offset)
+	c.Assert(err, Equals, ErrSeekNotSupported)
+}
+
 var expectedHeadersOFS = []ObjectHeader{
 	{Type: plumbing.CommitObject, Offset: 12, Length: 254},
 	{Type: plumbing.OFSDeltaObject, Offset: 186, Length: 93, OffsetReference: 12},