message: Add precond param test.
  + Using CG solver fac as Trs fac gen needs an exec.
diff: @@ -40,7 +40,7 @@ OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  #include <ginkgo/core/base/executor.hpp>
  -#include <ginkgo/core/matrix/identity.hpp>
  +#include <ginkgo/core/solver/cg.hpp>
  namespace {
  @@ -49,14 +49,16 @@ namespace {
  class Trs : public ::testing::Test {
  protected:
  using Solver = gko::solver::Trs<>;
  - using Precond = gko::matrix::Identity<>;
  + using CGSolver = gko::solver::Cg<>;
  Trs()
  : exec(gko::ReferenceExecutor::create()),
  - trs_factory(Solver::build().on(exec))
  + prec_fac(CGSolver::build().on(exec)),
  + trs_factory(Solver::build().with_preconditioner(prec_fac).on(exec))
  {}
  std::shared_ptr<const gko::Executor> exec;
  + std::shared_ptr<CGSolver::Factory> prec_fac;
  std::unique_ptr<Solver::Factory> trs_factory;
  };
  @@ -67,4 +69,12 @@ TEST_F(Trs, TrsFactoryKnowsItsExecutor)
  }
  +TEST_F(Trs, TrsFactoryKnowsItsPrecond)
  +{
  + ASSERT_EQ(static_cast<const CGSolver::Factory *>(
  + trs_factory->get_parameters().preconditioner.get()),
  + prec_fac.get());
  +}
  +
  +
  } // namespace
  