From 81a846fe7d85eb8dddb0d1327a5d6de6e1f40394 Mon Sep 17 00:00:00 2001
From: Nils Schween <symbolschubser@riseup.net>
Date: Tue, 14 Mar 2023 13:43:51 +0100
Subject: [PATCH] test to check if collect_periodic_faces works with
 parallel::shared::triangulation in all dim

---
 ...llect_period_faces_parallel_shared_tria.cc | 81 +++++++++++++++++++
 1 file changed, 81 insertions(+)
 create mode 100644 tests/grid/grid_tools_collect_period_faces_parallel_shared_tria.cc

diff --git a/tests/grid/grid_tools_collect_period_faces_parallel_shared_tria.cc b/tests/grid/grid_tools_collect_period_faces_parallel_shared_tria.cc
new file mode 100644
index 0000000000..626af3a889
--- /dev/null
+++ b/tests/grid/grid_tools_collect_period_faces_parallel_shared_tria.cc
@@ -0,0 +1,81 @@
+// ---------------------------------------------------------------------
+//
+// Copyright (C) 2001 - 2023 by the deal.II authors
+//
+// This file is part of the deal.II library.
+//
+// The deal.II library is free software; you can use it, redistribute
+// it, and/or modify it under the terms of the GNU Lesser General
+// Public License as published by the Free Software Foundation; either
+// version 2.1 of the License, or (at your option) any later version.
+// The full text of the license can be found in the file LICENSE.md at
+// the top level directory of deal.II.
+//
+// ---------------------------------------------------------------------
+
+#include <deal.II/base/exceptions.h>
+#include <deal.II/base/mpi.h>
+#include <deal.II/base/point.h>
+#include <deal.II/distributed/shared_tria.h>
+#include <deal.II/distributed/tria.h>
+#include <deal.II/grid/grid_generator.h>
+#include <deal.II/grid/grid_tools.h>
+#include <deal.II/grid/tria.h>
+
+#include <vector>
+using namespace dealii;
+template <int dim>
+void test(MPI_Comm comm) {
+  deallog << "dim = " << dim << std::endl;
+  parallel::shared::Triangulation<dim> tria(comm);
+
+  std::vector<typename GridTools::PeriodicFacePair<
+      typename parallel::shared::Triangulation<dim>::cell_iterator>>
+      matched_pairs;
+
+  unsigned int num_refinements = 1 << 4;
+
+  if constexpr (dim == 1) {
+    Point<dim> p1{0.};
+    Point<dim> p2{1.};
+    std::vector<unsigned int> repitions{num_refinements};
+    GridGenerator::subdivided_hyper_rectangle(tria, repitions, p1, p2, true);
+
+    // Collect periodic faces in the x-direction
+    GridTools::collect_periodic_faces(tria, 0, 1, 0, matched_pairs);
+    // Check the size of the matched_pairs vector
+    if (matched_pairs.size() != 1) {
+      // throw error
+    }
+  } else if constexpr (dim == 2) {
+    Point<dim> p1{0., 0.};
+    Point<dim> p2{1., 1.};
+    std::vector<unsigned int> repitions{num_refinements, num_refinements};
+    GridGenerator::subdivided_hyper_rectangle(tria, repitions, p1, p2, true);
+
+    GridTools::collect_periodic_faces(tria, 0, 1, 0, matched_pairs);
+    if (matched_pairs.size() != 16) {
+    }
+  } else if constexpr (dim == 3) {
+    Point<dim> p1{0., 0., 0.};
+    Point<dim> p2{1., 1., 1.};
+    std::vector<unsigned int> repitions{num_refinements, num_refinements,
+                                        num_refinements};
+    GridGenerator::subdivided_hyper_rectangle(tria, repitions, p1, p2, true);
+
+    GridTools::collect_periodic_faces(tria, 0, 1, 0, matched_pairs);
+    if (matched_pairs.size() != 256) {
+    }
+  }
+}
+
+int main(int argc, char *argv[]) {
+  Utilities::MPI::MPI_InitFinalize mpi_initialization(argc, argv, 1);
+  // mpi_initlog();
+  MPI_Comm comm = MPI_COMM_WORLD;
+  test<1>(comm);
+  test<2>(comm);
+  test<3>(comm);
+
+  return 0;
+}
-- 
2.39.5