Add wait_all unit test

unit_tests/CMakeLists.txt

@@ -86,6 +86,7 @@ target_sources(
     mpi/test_alltoall.cpp
     mpi/test_reduce.cpp
     mpi/test_allgather.cpp
+    mpi/test_waitall.cpp
     mpi/test_waitany.cpp
 )
 target_link_libraries(

unit_tests/mpi/test_waitall.cpp

@@ -0,0 +1,102 @@
+//@HEADER
+// ************************************************************************
+//
+//                        Kokkos v. 4.0
+//       Copyright (2022) National Technology & Engineering
+//               Solutions of Sandia, LLC (NTESS).
+//
+// Under the terms of Contract DE-NA0003525 with NTESS,
+// the U.S. Government retains certain rights in this software.
+//
+// Part of Kokkos, under the Apache License v2.0 with LLVM Exceptions.
+// See https://kokkos.org/LICENSE for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//@HEADER
+
+#include <gtest/gtest.h>
+#include <type_traits>
+#include <algorithm>  // iota
+#include <random>
+
+#include "KokkosComm/KokkosComm.hpp"
+
+namespace {
+
+using namespace KokkosComm::mpi;
+
+template <typename T>
+class MpiWaitAll : public testing::Test {
+ public:
+  using Scalar = T;
+};
+
+using ScalarTypes = ::testing::Types<int, double, Kokkos::complex<float>>;
+TYPED_TEST_SUITE(MpiWaitAll, ScalarTypes);
+
+template <KokkosComm::KokkosExecutionSpace ExecSpace, typename Scalar>
+void wait_all() {
+  using TestView = Kokkos::View<Scalar *>;
+
+  int rank, size;
+  MPI_Comm_rank(MPI_COMM_WORLD, &rank);
+  MPI_Comm_size(MPI_COMM_WORLD, &size);
+  if (size < 2) {
+    GTEST_SKIP() << "Requires >= 2 ranks (" << size << " provided)";
+  }
+
+  constexpr size_t numMsg = 128;
+  ExecSpace space;
+  std::vector<KokkosComm::Req<>> reqs;
+  std::vector<TestView> views;
+
+  for (size_t i = 0; i < numMsg; ++i) {
+    views.push_back(TestView(std::to_string(i), i));
+  }
+
+  constexpr unsigned int SEED = 31337;
+  std::random_device rd;
+  std::mt19937 g(SEED);
+
+  // random send/recv order
+  std::vector<size_t> order(numMsg);
+  std::iota(order.begin(), order.end(), size_t(0));
+  std::shuffle(order.begin(), order.end(), g);
+
+  KokkosComm::Handle<ExecSpace, KokkosComm::Mpi> h(space, MPI_COMM_WORLD);
+
+  if (0 == rank) {
+    constexpr int dst = 1;
+
+    for (size_t i : order) {
+      reqs.push_back(KokkosComm::send(h, views[i], dst));
+    }
+
+    KokkosComm::wait_all(reqs);
+
+  } else if (1 == rank) {
+    constexpr int src = 0;
+
+    for (size_t i : order) {
+      reqs.push_back(KokkosComm::recv(h, views[i], src));
+    }
+
+    KokkosComm::wait_all(reqs);
+  }
+}
+
+// TODO: test call on no requests
+
+TYPED_TEST(MpiWaitAll, default_execution_space) {
+  wait_all<Kokkos::DefaultExecutionSpace, typename TestFixture::Scalar>();
+}
+
+TYPED_TEST(MpiWaitAll, default_host_execution_space) {
+  if constexpr (std::is_same_v<Kokkos::DefaultHostExecutionSpace, Kokkos::DefaultExecutionSpace>) {
+    GTEST_SKIP() << "Skipping test: DefaultHostExecSpace = DefaultExecSpace";
+  } else {
+    wait_all<Kokkos::DefaultHostExecutionSpace, typename TestFixture::Scalar>();
+  }
+}
+
+}  // namespace