diff --git a/tests/clock-fixture.cpp b/tests/clock-fixture.cpp
new file mode 100644
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--- /dev/null
+++ b/tests/clock-fixture.cpp
@@ -0,0 +1,69 @@
+/* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil; -*- */
+/*
+ * Copyright (c) 2014-2019,  Regents of the University of California,
+ *                           Arizona Board of Regents,
+ *                           Colorado State University,
+ *                           University Pierre & Marie Curie, Sorbonne University,
+ *                           Washington University in St. Louis,
+ *                           Beijing Institute of Technology,
+ *                           The University of Memphis.
+ *
+ * This file is part of NFD (Named Data Networking Forwarding Daemon).
+ * See AUTHORS.md for complete list of NFD authors and contributors.
+ *
+ * NFD is free software: you can redistribute it and/or modify it under the terms
+ * of the GNU General Public License as published by the Free Software Foundation,
+ * either version 3 of the License, or (at your option) any later version.
+ *
+ * NFD is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY;
+ * without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR
+ * PURPOSE.  See the GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * NFD, e.g., in COPYING.md file.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include "tests/clock-fixture.hpp"
+
+namespace nfd {
+namespace tests {
+
+ClockFixture::ClockFixture(boost::asio::io_service& io)
+  : m_steadyClock(make_shared<time::UnitTestSteadyClock>())
+  , m_systemClock(make_shared<time::UnitTestSystemClock>())
+  , m_io(io)
+{
+  time::setCustomClocks(m_steadyClock, m_systemClock);
+}
+
+ClockFixture::~ClockFixture()
+{
+  time::setCustomClocks(nullptr, nullptr);
+}
+
+void
+ClockFixture::advanceClocks(time::nanoseconds tick, time::nanoseconds total)
+{
+  BOOST_ASSERT(tick > time::nanoseconds::zero());
+  BOOST_ASSERT(total >= time::nanoseconds::zero());
+
+  while (total > time::nanoseconds::zero()) {
+    auto t = std::min(tick, total);
+    m_steadyClock->advance(t);
+    m_systemClock->advance(t);
+    total -= t;
+
+    pollAfterClockTick();
+  }
+}
+
+void
+ClockFixture::pollAfterClockTick()
+{
+  if (m_io.stopped())
+    m_io.reset();
+  m_io.poll();
+}
+
+} // namespace tests
+} // namespace nfd