From bc10f12ad8074d6c5e9f752ed6ed8c81fa8cd728 Mon Sep 17 00:00:00 2001
From: "alex.sharov" <AskAlexSharov@gmail.com>
Date: Thu, 16 Mar 2023 10:26:44 +0700
Subject: [PATCH] don't loose nil value

---
 eth/stagedsync/exec3.go | 18 +++++++++++++++---
 1 file changed, 15 insertions(+), 3 deletions(-)

diff --git a/eth/stagedsync/exec3.go b/eth/stagedsync/exec3.go
index 5c30b737d7f..7d57320ee8f 100644
--- a/eth/stagedsync/exec3.go
+++ b/eth/stagedsync/exec3.go
@@ -1213,7 +1213,11 @@ func reconstituteStep(last bool,
 				}
 				lastKey = append(lastKey[:0], k[:len(k)-8]...)
 			}
-			lastVal = append(lastVal[:0], v...)
+			if v == nil { // `nil` value means delete, `empty value []byte{}` means empty value
+				lastVal = nil
+			} else {
+				lastVal = append(lastVal[:0], v...)
+			}
 			return nil
 		}, etl.TransformArgs{}); err != nil {
 			return err
@@ -1241,7 +1245,11 @@ func reconstituteStep(last bool,
 				}
 				lastKey = append(lastKey[:0], k[:len(k)-8]...)
 			}
-			lastVal = append(lastVal[:0], v...)
+			if v == nil {
+				lastVal = nil
+			} else {
+				lastVal = append(lastVal[:0], v...)
+			}
 			return nil
 		}, etl.TransformArgs{}); err != nil {
 			return err
@@ -1269,7 +1277,11 @@ func reconstituteStep(last bool,
 				}
 				lastKey = append(lastKey[:0], k[:len(k)-8]...)
 			}
-			lastVal = append(lastVal[:0], v...)
+			if v == nil {
+				lastVal = nil
+			} else {
+				lastVal = append(lastVal[:0], v...)
+			}
 			return nil
 		}, etl.TransformArgs{}); err != nil {
 			return err