fw: rename BestRouteStrategy2 class to BestRouteStrategy

Also rename ad-hoc-forwarding.t.cpp to strategy-ad-hoc-face.t.cpp
and broadcast-medium.t.cpp to strategy-broadcast-medium.t.cpp,
for consistency with the other strategy-*.t.cpp test suites.

Change-Id: Ia8f5257260563732d74c7d58e35481b73a231f06
diff --git a/tests/daemon/fw/best-route-strategy.t.cpp b/tests/daemon/fw/best-route-strategy.t.cpp
new file mode 100644
index 0000000..cd519b5
--- /dev/null
+++ b/tests/daemon/fw/best-route-strategy.t.cpp
@@ -0,0 +1,149 @@
+/* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil; -*- */
+/*
+ * Copyright (c) 2014-2021,  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 "fw/best-route-strategy.hpp"
+#include "common/global.hpp"
+
+#include "tests/test-common.hpp"
+#include "tests/daemon/face/dummy-face.hpp"
+#include "strategy-tester.hpp"
+
+namespace nfd {
+namespace fw {
+namespace tests {
+
+using BestRouteStrategyTester = StrategyTester<BestRouteStrategy>;
+NFD_REGISTER_STRATEGY(BestRouteStrategyTester);
+
+BOOST_AUTO_TEST_SUITE(Fw)
+
+class BestRouteStrategyFixture : public GlobalIoTimeFixture
+{
+protected:
+  BestRouteStrategyFixture()
+    : face1(make_shared<DummyFace>())
+    , face2(make_shared<DummyFace>())
+    , face3(make_shared<DummyFace>())
+    , face4(make_shared<DummyFace>())
+    , face5(make_shared<DummyFace>())
+  {
+    faceTable.add(face1);
+    faceTable.add(face2);
+    faceTable.add(face3);
+    faceTable.add(face4);
+    faceTable.add(face5);
+  }
+
+protected:
+  FaceTable faceTable;
+  Forwarder forwarder{faceTable};
+  BestRouteStrategyTester strategy{forwarder};
+  Fib& fib{forwarder.getFib()};
+  Pit& pit{forwarder.getPit()};
+
+  shared_ptr<DummyFace> face1;
+  shared_ptr<DummyFace> face2;
+  shared_ptr<DummyFace> face3;
+  shared_ptr<DummyFace> face4;
+  shared_ptr<DummyFace> face5;
+};
+
+BOOST_FIXTURE_TEST_SUITE(TestBestRouteStrategy, BestRouteStrategyFixture)
+
+BOOST_AUTO_TEST_CASE(Forward)
+{
+  fib::Entry& fibEntry = *fib.insert(Name()).first;
+  fib.addOrUpdateNextHop(fibEntry, *face1, 10);
+  fib.addOrUpdateNextHop(fibEntry, *face2, 20);
+  fib.addOrUpdateNextHop(fibEntry, *face3, 30);
+
+  shared_ptr<Interest> interest = makeInterest("ndn:/BzgFBchqA");
+  shared_ptr<pit::Entry> pitEntry = pit.insert(*interest).first;
+
+  const auto TICK = time::duration_cast<time::nanoseconds>(
+                      BestRouteStrategy::RETX_SUPPRESSION_INITIAL * 0.1);
+
+  // first Interest goes to nexthop with lowest FIB cost,
+  // however face1 is downstream so it cannot be used
+  pitEntry->insertOrUpdateInRecord(*face1, *interest);
+  strategy.afterReceiveInterest(FaceEndpoint(*face1, 0), *interest, pitEntry);
+  BOOST_REQUIRE_EQUAL(strategy.sendInterestHistory.size(), 1);
+  BOOST_CHECK_EQUAL(strategy.sendInterestHistory.back().outFaceId, face2->getId());
+
+  // downstream retransmits frequently, but the strategy should not send Interests
+  // more often than DEFAULT_MIN_RETX_INTERVAL
+  scheduler::EventId retxFrom4Evt;
+  size_t nSentLast = strategy.sendInterestHistory.size();
+  time::steady_clock::TimePoint timeSentLast = time::steady_clock::now();
+  std::function<void()> periodicalRetxFrom4; // let periodicalRetxFrom4 lambda capture itself
+  periodicalRetxFrom4 = [&] {
+    pitEntry->insertOrUpdateInRecord(*face4, *interest);
+    strategy.afterReceiveInterest(FaceEndpoint(*face4, 0), *interest, pitEntry);
+
+    size_t nSent = strategy.sendInterestHistory.size();
+    if (nSent > nSentLast) {
+      BOOST_CHECK_EQUAL(nSent - nSentLast, 1);
+      auto timeSent = time::steady_clock::now();
+      BOOST_CHECK_GE(timeSent - timeSentLast, TICK * 8);
+      nSentLast = nSent;
+      timeSentLast = timeSent;
+    }
+
+    retxFrom4Evt = getScheduler().schedule(TICK * 5, periodicalRetxFrom4);
+  };
+  periodicalRetxFrom4();
+  this->advanceClocks(TICK, BestRouteStrategy::RETX_SUPPRESSION_MAX * 16);
+  retxFrom4Evt.cancel();
+
+  // nexthops for accepted retransmissions: follow FIB cost,
+  // later forward to an eligible upstream with earliest out-record
+  BOOST_REQUIRE_GE(strategy.sendInterestHistory.size(), 6);
+  BOOST_CHECK_EQUAL(strategy.sendInterestHistory[1].outFaceId, face1->getId());
+  BOOST_CHECK_EQUAL(strategy.sendInterestHistory[2].outFaceId, face3->getId());
+  BOOST_CHECK_EQUAL(strategy.sendInterestHistory[3].outFaceId, face2->getId());
+  BOOST_CHECK_EQUAL(strategy.sendInterestHistory[4].outFaceId, face1->getId());
+  BOOST_CHECK_EQUAL(strategy.sendInterestHistory[5].outFaceId, face3->getId());
+
+  fib.removeNextHop(fibEntry, *face1);
+
+  strategy.sendInterestHistory.clear();
+  for (int i = 0; i < 3; ++i) {
+    this->advanceClocks(TICK, BestRouteStrategy::RETX_SUPPRESSION_MAX * 2);
+    pitEntry->insertOrUpdateInRecord(*face5, *interest);
+    strategy.afterReceiveInterest(FaceEndpoint(*face5, 0), *interest, pitEntry);
+  }
+  BOOST_REQUIRE_EQUAL(strategy.sendInterestHistory.size(), 3);
+  BOOST_CHECK_NE(strategy.sendInterestHistory[0].outFaceId, face1->getId());
+  BOOST_CHECK_NE(strategy.sendInterestHistory[1].outFaceId, face1->getId());
+  BOOST_CHECK_NE(strategy.sendInterestHistory[2].outFaceId, face1->getId());
+  // face1 cannot be used because it's gone from FIB entry
+}
+
+BOOST_AUTO_TEST_SUITE_END() // TestBestRouteStrategy
+BOOST_AUTO_TEST_SUITE_END() // Fw
+
+} // namespace tests
+} // namespace fw
+} // namespace nfd