Cell index serialization improved to visit only unique cells

tvm/cell/cell_test.go

@@ -212,6 +212,10 @@ func TestBOCBomb(t *testing.T) {
 	if !bytes.Equal(c.Hash(), hash) {
 		t.Fatal("incorrect hash", hex.EncodeToString(c.Hash()), hex.EncodeToString(hash))
 	}
+
+	if len(c.ToBOCWithFlags(false)) != len(boc) {
+		t.Fatal("len", len(c.ToBOC()), len(boc))
+	}
 }
 
 func TestCell_TxWithMerkleBody(t *testing.T) {

tvm/cell/flattenIndex.go

@@ -16,13 +16,18 @@ func flattenIndex(cells []*Cell) ([]*idxItem, map[string]*idxItem) {
 	for len(cells) > 0 {
 		next := make([]*Cell, 0, len(cells)*4)
 		for _, p := range cells {
+			hash := string(p.Hash())
+
+			if _, ok := index[hash]; ok {
+				continue
+			}
+
 			// move cell forward in boc, because behind reference is not allowed
-			index[string(p.Hash())] = &idxItem{
-				index: idx,
+			index[hash] = &idxItem{
 				cell:  p,
+				index: idx,
 			}
 			idx++
-
 			next = append(next, p.refs...)
 		}
 		cells = next
@@ -33,6 +38,26 @@ func flattenIndex(cells []*Cell) ([]*idxItem, map[string]*idxItem) {
 		idxSlice = append(idxSlice, id)
 	}
 
+	for verifyOrder := true; verifyOrder; {
+		verifyOrder = false
+
+		for _, id := range idxSlice {
+			for _, ref := range id.cell.refs {
+				idRef := index[string(ref.Hash())]
+
+				if idRef.index < id.index {
+					// if we found that ref index is behind parent,
+					// move ref index forward
+					idRef.index = idx
+					idx++
+
+					// we changed index, so we need to verify order again
+					verifyOrder = true
+				}
+			}
+		}
+	}
+
 	sort.Slice(idxSlice, func(i, j int) bool {
 		return idxSlice[i].index < idxSlice[j].index
 	})