diff --git a/tests/peek/ndnpoke.t.cpp b/tests/peek/ndnpoke.t.cpp
index 617b516..14fe305 100644
--- a/tests/peek/ndnpoke.t.cpp
+++ b/tests/peek/ndnpoke.t.cpp
@@ -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) 2014-2022,  Regents of the University of California,
  *                           Arizona Board of Regents,
  *                           Colorado State University,
  *                           University Pierre & Marie Curie, Sorbonne University,
@@ -31,9 +31,7 @@
 
 #include <ndn-cxx/util/dummy-client-face.hpp>
 
-namespace ndn {
-namespace peek {
-namespace tests {
+namespace ndn::peek::tests {
 
 using namespace ndn::tests;
 
@@ -256,6 +254,4 @@
 BOOST_AUTO_TEST_SUITE_END() // TestNdnPoke
 BOOST_AUTO_TEST_SUITE_END() // Peek
 
-} // namespace tests
-} // namespace peek
-} // namespace ndn
+} // namespace ndn::peek::tests