plumbing: packfile, fix package tests

Signed-off-by: Miguel Molina <miguel@erizocosmi.co>

2 files changed, 18 insertions, 1 deletions

diff --git a/plumbing/format/idxfile/idxfile.go b/plumbing/format/idxfile/idxfile.go
index d4a9365..71c7630 100644
--- a/plumbing/format/idxfile/idxfile.go
+++ b/plumbing/format/idxfile/idxfile.go
@@ -67,6 +67,10 @@ func (idx *MemoryIndex) findHashIndex(h plumbing.Hash) int {
 		return -1
 	}
 
+	if len(idx.Names) <= k {
+		return -1
+	}
+
 	data := idx.Names[k]
 	high := uint64(len(idx.Offset32[k])) >> 2
 	if high == 0 {
@@ -103,6 +107,10 @@ func (idx *MemoryIndex) Contains(h plumbing.Hash) (bool, error) {
 
 // FindOffset implements the Index interface.
 func (idx *MemoryIndex) FindOffset(h plumbing.Hash) (int64, error) {
+	if len(idx.FanoutMapping) <= int(h[0]) {
+		return 0, plumbing.ErrObjectNotFound
+	}
+
 	k := idx.FanoutMapping[h[0]]
 	i := idx.findHashIndex(h)
 	if i < 0 {
diff --git a/plumbing/format/idxfile/writer.go b/plumbing/format/idxfile/writer.go
index efcdcc6..a22cf16 100644
--- a/plumbing/format/idxfile/writer.go
+++ b/plumbing/format/idxfile/writer.go
@@ -25,6 +25,7 @@ type Writer struct {
 	offset64 uint32
 	finished bool
 	index    *MemoryIndex
+	added    map[plumbing.Hash]struct{}
 }
 
 // Index returns a previously created MemoryIndex or creates a new one if
@@ -45,7 +46,15 @@ func (w *Writer) Add(h plumbing.Hash, pos uint64, crc uint32) {
 	w.m.Lock()
 	defer w.m.Unlock()
 
-	w.objects = append(w.objects, Entry{h, crc, pos})
+	if w.added == nil {
+		w.added = make(map[plumbing.Hash]struct{})
+	}
+
+	if _, ok := w.added[h]; !ok {
+		w.added[h] = struct{}{}
+		w.objects = append(w.objects, Entry{h, crc, pos})
+	}
+
 }
 
 func (w *Writer) Finished() bool {