add minimal test for testing compute styles that compute global scalars

unittest/commands/CMakeLists.txt

@@ -41,6 +41,11 @@ target_compile_definitions(test_reset_ids PRIVATE -DTEST_INPUT_FOLDER=${CMAKE_CU
 target_link_libraries(test_reset_ids PRIVATE lammps GTest::GMock)
 add_test(NAME ResetIDs COMMAND test_reset_ids)
 
+add_executable(test_compute_global test_compute_global.cpp)
+target_compile_definitions(test_compute_global PRIVATE -DTEST_INPUT_FOLDER=${CMAKE_CURRENT_SOURCE_DIR})
+target_link_libraries(test_compute_global PRIVATE lammps GTest::GMock)
+add_test(NAME ComputeGlobal COMMAND test_compute_global)
+
 add_executable(test_mpi_load_balancing test_mpi_load_balancing.cpp)
 target_link_libraries(test_mpi_load_balancing PRIVATE lammps GTest::GMock)
 target_compile_definitions(test_mpi_load_balancing PRIVATE ${TEST_CONFIG_DEFS})

unittest/commands/test_compute_global.cpp

@@ -0,0 +1,115 @@
+/* ----------------------------------------------------------------------
+   LAMMPS - Large-scale Atomic/Molecular Massively Parallel Simulator
+   https://www.lammps.org/, Sandia National Laboratories
+   Steve Plimpton, sjplimp@sandia.gov
+
+   Copyright (2003) Sandia Corporation.  Under the terms of Contract
+   DE-AC04-94AL85000 with Sandia Corporation, the U.S. Government retains
+   certain rights in this software.  This software is distributed under
+   the GNU General Public License.
+
+   See the README file in the top-level LAMMPS directory.
+------------------------------------------------------------------------- */
+
+#include "../testing/core.h"
+#include "info.h"
+#include "input.h"
+#include "lammps.h"
+#include "library.h"
+#include "utils.h"
+#include "gmock/gmock.h"
+#include "gtest/gtest.h"
+
+#include <cstdio>
+#include <mpi.h>
+
+// whether to print verbose output (i.e. not capturing LAMMPS screen output).
+bool verbose = false;
+
+using LAMMPS_NS::utils::split_words;
+
+namespace LAMMPS_NS {
+
+#define STRINGIFY(val) XSTR(val)
+#define XSTR(val) #val
+
+class ComputeGlobalTest : public LAMMPSTest {
+protected:
+    void SetUp() override
+    {
+        testbinary = "ComputeGlobalTest";
+        LAMMPSTest::SetUp();
+        if (info->has_style("atom", "full")) {
+            BEGIN_HIDE_OUTPUT();
+            command("variable input_dir index \"" STRINGIFY(TEST_INPUT_FOLDER) "\"");
+            command("include \"${input_dir}/in.fourmol\"");
+            END_HIDE_OUTPUT();
+        }
+    }
+};
+
+TEST_F(ComputeGlobalTest, Energy)
+{
+    void *handle = (void *) lmp;
+    if (lammps_get_natoms(handle) == 0.0) GTEST_SKIP();
+
+    BEGIN_HIDE_OUTPUT();
+    command("group allwater molecule 3:6");
+    command("compute ke1 all ke");
+    command("compute ke2 allwater ke");
+    command("compute pe1 all pe");
+    command("compute pe2 all pe bond");
+    command("compute pe3 all pe angle dihedral");
+    command("pair_style lj/cut 10.0");
+    command("pair_coeff * * 0.01 3.0");
+    command("bond_style harmonic");
+    command("bond_coeff * 100.0 1.5");
+    command("thermo_style custom c_ke1 c_ke2 c_pe1 c_pe2 c_pe3");
+    command("run 0 post no");
+    END_HIDE_OUTPUT();
+
+    double ke1 = *(double *)lammps_extract_compute(handle, "ke1", LMP_STYLE_GLOBAL, LMP_TYPE_SCALAR);
+    double ke2 = *(double *)lammps_extract_compute(handle, "ke2", LMP_STYLE_GLOBAL, LMP_TYPE_SCALAR);
+    double pe1 = *(double *)lammps_extract_compute(handle, "pe1", LMP_STYLE_GLOBAL, LMP_TYPE_SCALAR);
+    double pe2 = *(double *)lammps_extract_compute(handle, "pe2", LMP_STYLE_GLOBAL, LMP_TYPE_SCALAR);
+    double pe3 = *(double *)lammps_extract_compute(handle, "pe3", LMP_STYLE_GLOBAL, LMP_TYPE_SCALAR);
+
+    EXPECT_DOUBLE_EQ(ke1, 2.3405256449146168);
+    EXPECT_DOUBLE_EQ(ke2, 1.192924237073665);
+    EXPECT_DOUBLE_EQ(pe1, 24280.922367235136);
+    EXPECT_DOUBLE_EQ(pe2, 361.37528652881286);
+    EXPECT_DOUBLE_EQ(pe3, 0.0);
+    
+
+    TEST_FAILURE(".*ERROR: Reuse of compute ID 'pe2'.*", command("compute pe2 all pe"););
+    TEST_FAILURE(".*ERROR: Compute pe must use group all.*", command("compute pe allwater pe"););
+    TEST_FAILURE(".*ERROR: Illegal compute command.*", command("compute pe potential"););
+}
+
+} // namespace LAMMPS_NS
+
+int main(int argc, char **argv)
+{
+    MPI_Init(&argc, &argv);
+    ::testing::InitGoogleMock(&argc, argv);
+
+    if (platform::mpi_vendor() == "Open MPI" && !LAMMPS_NS::Info::has_exceptions())
+        std::cout << "Warning: using OpenMPI without exceptions. "
+                     "Death tests will be skipped\n";
+
+    // handle arguments passed via environment variable
+    if (const char *var = getenv("TEST_ARGS")) {
+        std::vector<std::string> env = split_words(var);
+        for (auto arg : env) {
+            if (arg == "-v") {
+                verbose = true;
+            }
+        }
+    }
+
+    if ((argc > 1) && (strcmp(argv[1], "-v") == 0)) verbose = true;
+
+    int rv = RUN_ALL_TESTS();
+    MPI_Finalize();
+    return rv;
+}