From 956b6f7d95b6eccfc505750164386f0e2589fd47 Mon Sep 17 00:00:00 2001
From: stasatdaglabs <39559713+stasatdaglabs@users.noreply.github.com>
Date: Thu, 2 Apr 2020 17:47:51 +0300
Subject: [PATCH] [NOD-900] Fix bad key in Seek (#687)

* [NOD-900] Fix Seek not working at expected.

* [NOD-900] Wrap error messages.

* [NOD-900] Use ldbIterator.Key instead of LevelDBCursor.Key.

* [NOD-900] Add a comment.
---
 database/ffldb/ldb/cursor.go | 16 +++++++++-------
 1 file changed, 9 insertions(+), 7 deletions(-)

diff --git a/database/ffldb/ldb/cursor.go b/database/ffldb/ldb/cursor.go
index 43118a8c0..d1ea0248f 100644
--- a/database/ffldb/ldb/cursor.go
+++ b/database/ffldb/ldb/cursor.go
@@ -53,18 +53,20 @@ func (c *LevelDBCursor) Seek(key []byte) error {
 		return errors.New("cannot seek a closed cursor")
 	}
 
+	notFoundErr := errors.Wrapf(database.ErrNotFound, "key %s not "+
+		"found", hex.EncodeToString(key))
 	found := c.ldbIterator.Seek(key)
 	if !found {
-		return errors.Wrapf(database.ErrNotFound, "key %s not "+
-			"found", hex.EncodeToString(key))
+		return notFoundErr
 	}
-	currentKey, err := c.Key()
-	if err != nil {
-		return err
+
+	// Use c.ldbIterator.Key because c.Key removes the prefix from the key
+	currentKey := c.ldbIterator.Key()
+	if currentKey == nil {
+		return notFoundErr
 	}
 	if !bytes.Equal(currentKey, key) {
-		return errors.Wrapf(database.ErrNotFound, "key %s not "+
-			"found", hex.EncodeToString(key))
+		return notFoundErr
 	}
 
 	return nil