[dist] add test for default coll comm in row gatherer

Author: MarcelKoch

core/test/mpi/distributed/row_gatherer.cpp

@@ -76,6 +76,19 @@ TYPED_TEST(RowGatherer, CanDefaultConstruct)
 }
 
 
+TYPED_TEST(RowGatherer, HasDefaultCollectiveCommunicator)
+{
+ using RowGatherer = typename TestFixture::row_gatherer_type;
+
+ auto rg = RowGatherer::create(this->ref, this->comm);
+
+ auto coll_comm = rg->get_collective_communicator();
+ ASSERT_NE(std::dynamic_pointer_cast<
+ const gko::experimental::mpi::DenseCommunicator>(coll_comm),
+ nullptr);
+}
+
+
 TYPED_TEST(RowGatherer, CanConstructWithEmptyCollectiveCommAndIndexMap)
 {
  using RowGatherer = typename TestFixture::row_gatherer_type;