Design and Define New UnitTest infrastructure

[crtrott]

A systematic new unit test framework shall be defined laying out how to add new unit tests.

[crtrott]

The new structure for unit tests was (mostly) implemented for the dot product. The basic structure to allow for maximum maintainability is as follows:

In the unit_test directory contains a number of directories:

openmp
cuda
serial
threads
blas
sparse
graph

Other than that only one file Test_Main.cpp is included. That file will not generally be changed.
Inside of the blast,sparse and graph subdirectories header files with the actual tests will be defined using a naming scheme of:

Test_CATEGORY_FUNCTION.hpp

where CATEGORY is for example: Blas1, Blas2, Sparse, Graph and FUNCTION is for example Dot, AXPBY, Update, GEMV etc.. An example is

Test_Blas1_Dot.hpp

The execution space directories contain one header file Test_EXECSPACE.hpp which generally is not touched, and the actual cpp files to instantiate the tests:

Test_EXECSPACE_CATEGORY_FUNCTION.cpp

for example

Test_OpenMP_Blas1_Dot.cpp

These cpp files will only have to include lines for example:

#include<Test_OpenMP.hpp>
#include<Test_Blas1_Dot.hpp>

In the actual Test header file the tests are defined through there internal implementation and the gtest macros. The Test_EXECSPACE.hpp files define two things to be used inside the test file:

#define TestCategory openmp
#define TestExecSpace Kokkos::OpenMP

This allows generic declarations inside of the actual test header files. For example:

#if defined(KOKKOSKERNELS_INST_FLOAT) || !defined(KOKKOSKERNELS_ETI_ONLY)
TEST_F( TestCategory, dot_float ) {
    test_dot<float,TestExecSpace> ();
}
#endif

#if defined(KOKKOSKERNELS_INST_DOUBLE) || !defined(KOKKOSKERNELS_ETI_ONLY)
TEST_F( TestCategory, dot_double ) {
    test_dot<double,TestExecSpace> ();
}
#endif

#if defined(KOKKOSKERNELS_INST_INT) || !defined(KOKKOSKERNELS_ETI_ONLY)
TEST_F( TestCategory, dot_int ) {
    test_dot<int,TestExecSpace> ();
}
#endif

Note the explicit scalar type instantiation as well as the inclusion of the scalar type into the test name (dot_int). The ETI guards make sure that the tests are only instantiated if either any instantiation is allowed (KOKKOSKERNELS_ETI_ONLY not defined) or the appropriate type is included in the ETI list.