add test program template for testing the PYTHON package

unittest/python/CMakeLists.txt

@@ -1,3 +1,13 @@
+# Test calling Python from LAMMPS (and importing the LAMMPS module
+# inside those functions). This can do an "anonymous" import of symbols
+# from the executable, so the shared library is not needed. The
+# availability of the PYTHON package is tested for inside the tester.
+
+add_executable(test_python_package test_python_package.cpp)
+target_link_libraries(test_python_package PRIVATE lammps GTest::GMock GTest::GTest)
+add_test(NAME PythonPackage COMMAND test_python_package WORKING_DIRECTORY ${CMAKE_CURRENT_BINARY_DIR})
+set_tests_properties(PythonPackage PROPERTIES ENVIRONMENT "LAMMPS_POTENTIALS=${LAMMPS_POTENTIALS_DIR};PYTHONPATH=${CMAKE_CURRENT_BINARY_DIR}:${LAMMPS_PYTHON_DIR}:$ENV{PYTHONPATH}")
+
 # we must have shared libraries enabled for testing the python module
 if(NOT BUILD_SHARED_LIBS)
   message(STATUS "Skipping Tests for the LAMMPS Python Module: must enable BUILD_SHARED_LIBS")

unittest/python/test_python_package.cpp

@@ -0,0 +1,91 @@
+/* ----------------------------------------------------------------------
+   LAMMPS - Large-scale Atomic/Molecular Massively Parallel Simulator
+   http://lammps.sandia.gov, 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 "atom.h"
+#include "input.h"
+#include "gmock/gmock.h"
+#include "gtest/gtest.h"
+
+#include <cmath>
+#include <cstring>
+#include <vector>
+
+// whether to print verbose output (i.e. not capturing LAMMPS screen output).
+bool verbose = false;
+
+using LAMMPS_NS::utils::split_words;
+
+namespace LAMMPS_NS {
+using ::testing::Eq;
+
+
+class PythonPackageTest : public ::testing::Test {
+protected:
+    LAMMPS *lmp;
+
+    void SetUp() override
+    {
+        const char *args[] = {"PythonPackageTest", "-log", "none", "-echo", "screen", "-nocite"};
+        char **argv        = (char **)args;
+        int argc           = sizeof(args) / sizeof(char *);
+        if (!verbose) ::testing::internal::CaptureStdout();
+        lmp = new LAMMPS(argc, argv, MPI_COMM_WORLD);
+        if (!verbose) ::testing::internal::GetCapturedStdout();
+        ASSERT_NE(lmp, nullptr);
+        if (!verbose) ::testing::internal::CaptureStdout();
+        lmp->input->one("units real");
+        lmp->input->one("dimension 3");
+        lmp->input->one("region box block -4 4 -4 4 -4 4");
+        lmp->input->one("create_box 1 box");
+        lmp->input->one("create_atoms 1 single  0.0  0.0 0.0    units box");
+        lmp->input->one("create_atoms 1 single  1.9 -1.9 1.9999 units box");
+        lmp->input->one("pair_style zero 2.0");
+        lmp->input->one("pair_coeff * *");
+        lmp->input->one("mass * 1.0");
+        if (!verbose) ::testing::internal::GetCapturedStdout();
+    }
+
+    void TearDown() override
+    {
+        if (!verbose) ::testing::internal::CaptureStdout();
+        delete lmp;
+        if (!verbose) ::testing::internal::GetCapturedStdout();
+    }
+};
+
+TEST_F(PythonPackageTest, python_invoke)
+{
+}
+    
+} // namespace LAMMPS_NS
+
+int main(int argc, char **argv)
+{
+    MPI_Init(&argc, &argv);
+    ::testing::InitGoogleMock(&argc, argv);
+
+    // 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;
+}