Detect unread MPI messages (#162)

Co-authored-by: Nesterov Alexander <[email protected]>

Author: kmichaelk

tasks/mpi/runner.cpp

@@ -3,13 +3,35 @@
 #include <boost/mpi/communicator.hpp>
 #include <boost/mpi/environment.hpp>
 
+class UnreadMessagesDetector : public ::testing::EmptyTestEventListener {
+ public:
+  UnreadMessagesDetector(boost::mpi::communicator world) : world_(std::move(world)) {}
+
+  void OnTestEnd(const ::testing::TestInfo& test_info) override {
+    world_.barrier();
+    if (const auto msg = world_.iprobe(boost::mpi::any_source, boost::mpi::any_tag)) {
+      fprintf(
+          stderr,
+          "[  PROCESS %d  ] [  FAILED  ] %s.%s: MPI message queue has an unread message from process %d with tag %d\n",
+          world_.rank(), test_info.test_suite_name(), test_info.name(), msg->source(), msg->tag());
+      exit(2);
+    }
+    world_.barrier();
+  }
+
+ private:
+  boost::mpi::communicator world_;
+};
+
 int main(int argc, char** argv) {
   boost::mpi::environment env(argc, argv);
   boost::mpi::communicator world;
+
   ::testing::InitGoogleTest(&argc, argv);
-  ::testing::TestEventListeners& listeners = ::testing::UnitTest::GetInstance()->listeners();
+  auto& listeners = ::testing::UnitTest::GetInstance()->listeners();
   if (world.rank() != 0) {
     delete listeners.Release(listeners.default_result_printer());
   }
+  listeners.Append(new UnreadMessagesDetector(world));
   return RUN_ALL_TESTS();
 }