Test for Monitoring::Hub::Entity::mergeAndReset

GaudiKernel/tests/src/CounterHistosUnitTest.cpp

@@ -24,8 +24,17 @@ struct ServiceLocator {
   MonitoringHub  m_monitHub{};
 };
 struct Algo {
-  ServiceLocator* serviceLocator() { return new ServiceLocator; }
+  ServiceLocator* serviceLocator() { return &m_serviceLocator; }
   std::string     name() { return ""; }
+  ServiceLocator m_serviceLocator{};
+};
+struct HistSink : public Gaudi::Monitoring::Hub::Sink {
+  virtual void registerEntity(Gaudi::Monitoring::Hub::Entity ent) override { m_entities.push_back(ent); }
+  virtual void removeEntity(Gaudi::Monitoring::Hub::Entity const& ent) override {
+    auto it = std::find(begin(m_entities), end(m_entities), ent);
+    if (it != m_entities.end()) m_entities.erase(it);
+  }
+  std::deque<Gaudi::Monitoring::Hub::Entity> m_entities;
 };
 
 BOOST_AUTO_TEST_CASE( test_counter_histos, *boost::unit_test::tolerance( 1e-14 ) ) {
@@ -109,6 +118,41 @@ BOOST_AUTO_TEST_CASE( test_custom_axis ) {
   BOOST_TEST( j["axis"][0]["labels"] == expected_labels );
 }
 
+BOOST_AUTO_TEST_CASE( test_histos_merge_reset, *boost::unit_test::tolerance( 1e-14 ) ) {
+  using namespace Gaudi::Accumulators;
+  Algo algo;
+  HistSink histSink;
+  algo.serviceLocator()->monitoringHub().addSink(&histSink);
+
+  Histogram<1, atomicity::full, float> hist1(&algo, "TestHist1", "Test histogram 1", Axis<float>{10, 0., 10.});
+  Histogram<1, atomicity::full, float> hist2(&algo, "TestHist2", "Test histogram 2", Axis<float>{10, 0., 10.});
+
+  // test all combinations of entities made (a) as part of the Histogram's constructor and (b) separately
+  auto ent1a = histSink.m_entities[0];
+  auto ent2a = histSink.m_entities[1];
+
+  Gaudi::Monitoring::Hub::Entity ent1b("","TestHist1",std::string("histogram:Histogram:")+typeid(float).name(),hist1);
+  Gaudi::Monitoring::Hub::Entity ent2b("","TestHist2",std::string("histogram:Histogram:")+typeid(float).name(),hist2);
+
+  for ( int i=0; i<10; ++i) {
+    hist1[i] += i;
+    hist2[i] += 2*i;
+  }
+
+  ent1a.mergeAndReset(ent2a);
+  BOOST_TEST(hist1.toJSON().at( "nEntries" ).get<unsigned long>() == 135);
+  BOOST_TEST(hist2.toJSON().at( "nEntries" ).get<unsigned long>() == 0);
+  ent2b.mergeAndReset(ent1b);
+  BOOST_TEST(hist1.toJSON().at( "nEntries" ).get<unsigned long>() == 0);
+  BOOST_TEST(hist2.toJSON().at( "nEntries" ).get<unsigned long>() == 135);
+  ent1a.mergeAndReset(ent2b);
+  BOOST_TEST(hist1.toJSON().at( "nEntries" ).get<unsigned long>() == 135);
+  BOOST_TEST(hist2.toJSON().at( "nEntries" ).get<unsigned long>() == 0);
+  ent2b.mergeAndReset(ent1a);
+  BOOST_TEST(hist1.toJSON().at( "nEntries" ).get<unsigned long>() == 0);
+  BOOST_TEST(hist2.toJSON().at( "nEntries" ).get<unsigned long>() == 135);
+}
+
 BOOST_AUTO_TEST_CASE( test_2d_histos, *boost::unit_test::tolerance( 1e-14 ) ) {
   using namespace Gaudi::Accumulators;
   Algo algo;