diff --git a/tests/unit/util/sha256.t.cpp b/tests/unit/util/sha256.t.cpp
index c5fd1fd..4a31ac7 100644
--- a/tests/unit/util/sha256.t.cpp
+++ b/tests/unit/util/sha256.t.cpp
@@ -1,6 +1,6 @@
 /* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil; -*- */
 /*
- * Copyright (c) 2013-2022 Regents of the University of California.
+ * Copyright (c) 2013-2023 Regents of the University of California.
  *
  * This file is part of ndn-cxx library (NDN C++ library with eXperimental eXtensions).
  *
@@ -27,9 +27,9 @@
 #include <boost/endian/conversion.hpp>
 #include <sstream>
 
-namespace ndn {
-namespace util {
-namespace tests {
+namespace ndn::tests {
+
+using ndn::util::Sha256;
 
 BOOST_AUTO_TEST_SUITE(Util)
 BOOST_AUTO_TEST_SUITE(TestSha256)
@@ -201,6 +201,4 @@
 BOOST_AUTO_TEST_SUITE_END() // TestSha256
 BOOST_AUTO_TEST_SUITE_END() // Util
 
-} // namespace tests
-} // namespace util
-} // namespace ndn
+} // namespace ndn::tests