diff --git a/tests/unit/static-data.hpp b/tests/unit/static-data.hpp
index 0df6540..7bee43d 100644
--- a/tests/unit/static-data.hpp
+++ b/tests/unit/static-data.hpp
@@ -1,6 +1,6 @@
 /* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil; -*- */
 /*
- * Copyright (c) 2014-2020, Regents of the University of California
+ * Copyright (c) 2014-2023, Regents of the University of California
  *
  * NAC library is free software: you can redistribute it and/or modify it under the
  * terms of the GNU Lesser General Public License as published by the Free Software
@@ -22,9 +22,7 @@
 
 #include "common.hpp"
 
-namespace ndn {
-namespace nac {
-namespace tests {
+namespace ndn::nac::tests {
 
 struct StaticData
 {
@@ -53,8 +51,6 @@
   };
 };
 
-} // namespace tests
-} // namespace nac
-} // namespace ndn
+} // namespace ndn::nac::tests
 
 #endif // NAC_TESTS_UNIT_STATIC_DATA_HPP