#476 add unit test

tests/unit/collection/test_lb.extended.cc

@@ -578,6 +578,81 @@ INSTANTIATE_TEST_SUITE_P(
   DumpUserdefinedDataExplode, TestDumpUserdefinedData, booleans
 );
 
+struct SerdeTestCol : vt::Collection<SerdeTestCol, vt::Index1D> {
+  template <typename SerializerT> void serialize(SerializerT &s) {
+    vt::Collection<SerdeTestCol, vt::Index1D>::serialize(s);
+
+    if (s.isSizing()) {
+      s | was_packed | was_unpacked | packed_on_node | unpacked_on_node;
+      return;
+    }
+
+    was_packed = was_unpacked = false;
+    packed_on_node = unpacked_on_node = -1;
+
+    if (s.isPacking()) {
+      was_packed = true;
+      packed_on_node = theContext()->getNode();
+    }
+
+    s | was_packed | was_unpacked | packed_on_node | unpacked_on_node;
+
+    if (s.isUnpacking()) {
+      was_unpacked = true;
+      unpacked_on_node = theContext()->getNode();
+    }
+  }
+
+  bool was_packed = false;
+  bool was_unpacked = false;
+  int packed_on_node = -1;
+  int unpacked_on_node = -1;
+};
+
+using SerdeTestMsg = vt::CollectionMessage<SerdeTestCol>;
+
+void serdeColHandler(SerdeTestMsg *, SerdeTestCol *col) {
+  auto const cur_phase = thePhase()->getCurrentPhase();
+  if (cur_phase < 2) {
+    return;
+  }
+
+  EXPECT_TRUE(col->was_packed);
+  EXPECT_TRUE(col->was_unpacked);
+  EXPECT_EQ(col->packed_on_node, col->unpacked_on_node);
+}
+
+void runSerdeTest() {
+  theConfig()->vt_lb = true;
+  theConfig()->vt_lb_name = "SerdeTestLB";
+  if (theContext()->getNode() == 0) {
+    ::fmt::print("Testing LB: SerdeTestLB\n");
+  }
+
+  theCollective()->barrier();
+
+  auto range = Index1D{8};
+  vrt::collection::CollectionProxy<SerdeTestCol> proxy;
+
+  runInEpochCollective([&] {
+    proxy = theCollection()->constructCollective<SerdeTestCol>(range);
+  });
+
+  for (int phase = 0; phase < num_phases; ++phase) {
+    runInEpochCollective([&] {
+      proxy.broadcastCollective<SerdeTestMsg, serdeColHandler>();
+    });
+    thePhase()->nextPhaseCollective();
+  }
+}
+
+struct TestLoadBalancerSerdeTestLB : TestParallelHarness {};
+
+TEST_F(TestLoadBalancerSerdeTestLB, test_SerdeTestLB_load_balancer) {
+  theCollective()->barrier();
+  runSerdeTest();
+}
+
 }}}} // end namespace vt::tests::unit::lb
 
 #endif /*vt_check_enabled(lblite)*/