// Copyright (c) 2010-2023, Lawrence Livermore National Security, LLC. Produced
// at the Lawrence Livermore National Laboratory. All Rights reserved. See files
// LICENSE and NOTICE for details. LLNL-CODE-806117.
//
// This file is part of the MFEM library. For more information and source code
// availability visit https://mfem.org.
//
// MFEM is free software; you can redistribute it and/or modify it under the
// terms of the BSD-3 license. We welcome feedback and contributions, see file
// CONTRIBUTING.md for details.

#include "mfem.hpp"
#include "unit_tests.hpp"

#ifdef MFEM_USE_EXCEPTIONS

using namespace mfem;

TEST_CASE("Operator", "[Operator]")
{
   // Define diagonal sparse matrix
   Vector diag(5);
   diag = 12.34;

   SparseMatrix A(diag);

   CGSolver cg;
   cg.SetOperator(A);

   SECTION("ProductNotIterative")
   {
      // When cg is in a product (on the right), we require cg->iterative_mode to be false.

      // First, test that the failing version throws an exception.
      cg.iterative_mode = true;
      REQUIRE_THROWS(ProductOperator(&A, &cg, false, false));
      REQUIRE_THROWS(TripleProductOperator(&A, &cg, &cg, false, false,
                                           false));
      REQUIRE_THROWS(RAPOperator(A, cg, cg));

      // Second, test that the correct version does not throw.
      cg.iterative_mode = false;
      REQUIRE_NOTHROW(ProductOperator(&A, &cg, false, false));
      REQUIRE_NOTHROW(TripleProductOperator(&A, &cg, &cg, false, false,
                                            false));
      REQUIRE_NOTHROW(RAPOperator(A, cg, cg));
   }
}

#endif  // MFEM_USE_EXCEPTIONS