t8_gtest_ancestor_id.cxx

/*
  This file is part of t8code.
  t8code is a C library to manage a collection (a forest) of multiple
  connected adaptive space-trees of general element classes in parallel.

  Copyright (C) 2025 the developers

  t8code is free software; you can redistribute it and/or modify
  it under the terms of the GNU General Public License as published by
  the Free Software Foundation; either version 2 of the License, or
  (at your option) any later version.

  t8code is distributed in the hope that it will be useful,
  but WITHOUT ANY WARRANTY; without even the implied warranty of
  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  GNU General Public License for more details.

  You should have received a copy of the GNU General Public License
  along with t8code; if not, write to the Free Software Foundation, Inc.,
  51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
*/

/** \file t8_gtest_ancestor_id.cxx
 * This test checks that the ancestor id of an element at level elem.level is the same
 * as the child id of the element. This traverses up the tree and checks if the ancestor id
 * at elem.level - 1, -2, ... is the same as the child id of the parent, grandparent and so on. 
 */

#include <gtest/gtest.h>
#include <t8_eclass.h>
#include <t8_schemes/t8_default/t8_default.hxx>
#include <test/t8_gtest_custom_assertion.hxx>
#include "t8_gtest_dfs_base.hxx"
#include <test/t8_gtest_macros.hxx>

struct class_ancestor_id: public TestDFS
{
 private:
  void
  check_element () override
  {
    t8_element_t *ancestor;
    scheme->element_new (eclass, 1, &ancestor);
    /* Get level of current element */
    const int level = scheme->element_get_level (eclass, element);

    /* Iterate over all levels above the current element and check
    if ancestor id corresponds with the child id of elem, parent, grandparent, ... */
    for (int levels_above_elem = 0; levels_above_elem < level; levels_above_elem++) {
      const int ancestor_level = level - levels_above_elem;
      const int ancestor_id = scheme->element_get_ancestor_id (eclass, element, ancestor_level);
      /* Compute elem/parent/grandparent... */
      scheme->element_copy (eclass, element, ancestor);
      for (int level_diff = 0; level_diff < levels_above_elem; level_diff++) {
        scheme->element_get_parent (eclass, ancestor, ancestor);
      }
      const int child_id = scheme->element_get_child_id (eclass, ancestor);
      EXPECT_EQ (ancestor_id, child_id);
    }
    scheme->element_destroy (eclass, 1, &ancestor);
  }

 protected:
  void
  SetUp () override
  {
    /* Setup DFS test */
    dfs_test_setup ();
  }
  void
  TearDown () override
  {
    /* Destroy DFS test */
    dfs_test_teardown ();
  }
};

TEST_P (class_ancestor_id, t8_recursive_dfs_ancestor_id)
{
#if T8_TEST_LEVEL_INT >= 1
  const int maxlvl = 4;
#else
  const int maxlvl = 6;
#endif
  check_recursive_dfs_to_max_lvl (maxlvl);
}

INSTANTIATE_TEST_SUITE_P (t8_gtest_ancestor_id, class_ancestor_id, AllSchemes, print_all_schemes);