From 63c08259d9c14b1078202fc42f2013b8f6fead1b Mon Sep 17 00:00:00 2001
From: Oleg Baranov <xssnick8@gmail.com>
Date: Mon, 15 May 2023 09:22:27 +0400
Subject: [PATCH] Fixed bits calculation for message either serialization

---
 tlb/message.go      |  6 +++---
 tlb/message_test.go | 26 ++++++++++++++++++++++++++
 2 files changed, 29 insertions(+), 3 deletions(-)

diff --git a/tlb/message.go b/tlb/message.go
index b46d56f1..e9e00e0c 100644
--- a/tlb/message.go
+++ b/tlb/message.go
@@ -210,7 +210,7 @@ func (m *InternalMessage) ToCell() (*cell.Cell, error) {
 	}
 
 	if m.Body != nil {
-		if b.BitsLeft() < m.Body.BitsSize() {
+		if int(b.BitsLeft())-1 < int(m.Body.BitsSize()) {
 			b.MustStoreBoolBit(true)
 			b.MustStoreRef(m.Body)
 		} else {
@@ -242,7 +242,7 @@ func (m *ExternalMessage) ToCell() (*cell.Cell, error) {
 			return nil, fmt.Errorf("failed to serialize state init: %w", err)
 		}
 
-		if builder.BitsLeft()-2 < stateCell.BitsSize() || builder.RefsLeft()-2 < m.Body.RefsNum() {
+		if int(builder.BitsLeft())-2 < int(stateCell.BitsSize()) || int(builder.RefsLeft())-2 < int(m.Body.RefsNum()) {
 			builder.MustStoreBoolBit(true) // state as ref
 			builder.MustStoreRef(stateCell)
 		} else {
@@ -251,7 +251,7 @@ func (m *ExternalMessage) ToCell() (*cell.Cell, error) {
 		}
 	}
 
-	if builder.BitsLeft() < m.Body.BitsSize() || builder.RefsLeft() < m.Body.RefsNum() {
+	if int(builder.BitsLeft())-1 < int(m.Body.BitsSize()) || builder.RefsLeft() < m.Body.RefsNum() {
 		builder.MustStoreBoolBit(true) // body as ref
 		builder.MustStoreRef(m.Body)
 	} else {
diff --git a/tlb/message_test.go b/tlb/message_test.go
index 29696c04..583be6bc 100644
--- a/tlb/message_test.go
+++ b/tlb/message_test.go
@@ -1,6 +1,8 @@
 package tlb
 
 import (
+	"bytes"
+	"encoding/hex"
 	"testing"
 
 	"github.com/xssnick/tonutils-go/address"
@@ -50,6 +52,30 @@ func TestInternalMessage_ToCell(t *testing.T) { // need to deploy contract on te
 	}
 }
 
+func TestCornerMessage(t *testing.T) {
+	msgBoc, _ := hex.DecodeString("b5ee9c724101020100860001b36800bf4c6bdca25797e55d700c1a5448e2af5d1ac16f9a9628719a4e1eb2b44d85e33fd104a366f6fb17799871f82e00e4f2eb8ae6aaf6d3e0b3fb346cd0208e23725e14094ba15d20071f12260000446ee17a9b0cc8c028d8c001004d8002b374733831aac3455708e8f1d2c7f129540b982d3a5de8325bf781083a8a3d2a04a7f943813277f3ea")
+
+	c, err := cell.FromBOC(msgBoc)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	var m InternalMessage
+	err = LoadFromCell(&m, c.BeginParse())
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	c2, err := ToCell(m)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	if !bytes.Equal(c.Hash(), c2.Hash()) {
+		t.Fatal("hash not match")
+	}
+}
+
 func TestMessage_LoadFromCell(t *testing.T) {
 	t.Run("internal msg case", func(t *testing.T) {
 		var msg Message