use common main function that allows handling of common command line flags.

unittest/c-library/CMakeLists.txt

@@ -1,13 +1,13 @@
 
-add_executable(test_library_open test_library_open.cpp)
-target_link_libraries(test_library_open PRIVATE lammps GTest::GTest GTest::GTestMain)
+add_executable(test_library_open test_library_open.cpp test_main.cpp)
+target_link_libraries(test_library_open PRIVATE lammps GTest::GTest GTest::GMock)
 add_test(LibraryOpen test_library_open)
 
-add_executable(test_library_commands test_library_commands.cpp)
-target_link_libraries(test_library_commands PRIVATE lammps GTest::GTest GTest::GTestMain)
+add_executable(test_library_commands test_library_commands.cpp test_main.cpp)
+target_link_libraries(test_library_commands PRIVATE lammps GTest::GTest GTest::GMock)
 add_test(LibraryCommands test_library_commands)
 
-add_executable(test_library_properties test_library_properties.cpp)
-target_link_libraries(test_library_properties PRIVATE lammps GTest::GTest GTest::GTestMain)
+add_executable(test_library_properties test_library_properties.cpp test_main.cpp)
+target_link_libraries(test_library_properties PRIVATE lammps GTest::GTest GTest::GMock)
+target_compile_definitions(test_library_properties PRIVATE -DTEST_INPUT_FOLDER=${CMAKE_CURRENT_SOURCE_DIR})
 add_test(LibraryProperties test_library_properties)
-

unittest/c-library/test_library_properties.cpp

@@ -1,53 +1,87 @@
 // unit tests for checking and changing simulation properties through the library interface
 
-#include "library.h"
 #include "lammps.h"
+#include "library.h"
 #include <string>
 
+#include "gmock/gmock.h"
 #include "gtest/gtest.h"
 
-const char *demo_input[] = {
-      "region       box block 0 $x 0 2 0 2",
-      "create_box 1 box",
-      "create_atoms 1 single 1.0 1.0 ${zpos}" };
-const char *cont_input[] = {
-    "create_atoms 1 single &",
-    "0.2 0.1 0.1" };
+#include "test_main.h"
 
-class LAMMPS_properties : public ::testing::Test
-{
+#define STRINGIFY(val) XSTR(val)
+#define XSTR(val) #val
+
+using ::testing::HasSubstr;
+using ::testing::StartsWith;
+
+class LAMMPS_properties : public ::testing::Test {
 protected:
     void *lmp;
-    LAMMPS_properties() {};
-    ~LAMMPS_properties() override {};
+    std::string INPUT_DIR = STRINGIFY(TEST_INPUT_FOLDER);
+
+    LAMMPS_properties(){};
+    ~LAMMPS_properties() override{};
+
+    void SetUp() override
+    {
+        const char *args[] = {"LAMMPS_test", "-log",      "none",
+                              "-echo",       "screen",    "-nocite",
+                              "-var",        "input_dir", STRINGIFY(TEST_INPUT_FOLDER)};
 
-    void SetUp() override {
-        const char *args[] = {"LAMMPS_test", "-log", "none",
-                              "-echo", "screen", "-nocite" };
         char **argv = (char **)args;
-        int argc = sizeof(args)/sizeof(char *);
+        int argc    = sizeof(args) / sizeof(char *);
 
         ::testing::internal::CaptureStdout();
-        lmp = lammps_open_no_mpi(argc, argv, NULL);
+        lmp                = lammps_open_no_mpi(argc, argv, NULL);
         std::string output = ::testing::internal::GetCapturedStdout();
-        EXPECT_STREQ(output.substr(0,8).c_str(), "LAMMPS (");
+        if (verbose) std::cout << output;
+        EXPECT_THAT(output, StartsWith("LAMMPS ("));
     }
-    void TearDown() override {
+    void TearDown() override
+    {
         ::testing::internal::CaptureStdout();
         lammps_close(lmp);
         std::string output = ::testing::internal::GetCapturedStdout();
-        EXPECT_STREQ(output.substr(0,16).c_str(), "Total wall time:");
+        EXPECT_THAT(output, HasSubstr("Total wall time:"));
+        if (verbose) std::cout << output;
         lmp = nullptr;
     }
 };
 
-TEST_F(LAMMPS_properties, get_mpi_comm) {
-    int f_comm = lammps_get_mpi_comm(lmp);
-    if (lammps_config_has_mpi_support())
-        EXPECT_GE(f_comm,0);
-    else
-        EXPECT_EQ(f_comm,-1);
+TEST_F(LAMMPS_properties, version)
+{
+    EXPECT_GE(20200824, lammps_version(lmp));
 };
 
-TEST_F(LAMMPS_properties, box) {
+TEST_F(LAMMPS_properties, get_mpi_comm)
+{
+    int f_comm = lammps_get_mpi_comm(lmp);
+    if (lammps_config_has_mpi_support())
+        EXPECT_GE(f_comm, 0);
+    else
+        EXPECT_EQ(f_comm, -1);
+};
+
+TEST_F(LAMMPS_properties, natoms)
+{
+    std::string input = INPUT_DIR + PATH_SEP + "in.fourmol";
+    if (!verbose) ::testing::internal::CaptureStdout();
+    lammps_file(lmp, input.c_str());
+    if (!verbose) ::testing::internal::GetCapturedStdout();
+    EXPECT_EQ(lammps_get_natoms(lmp), 29);
+};
+
+TEST_F(LAMMPS_properties, thermo)
+{
+    std::string input = INPUT_DIR + PATH_SEP + "in.fourmol";
+    if (!verbose) ::testing::internal::CaptureStdout();
+    lammps_file(lmp, input.c_str());
+    lammps_command(lmp, "run 2 post no");
+    if (!verbose) ::testing::internal::GetCapturedStdout();
+    EXPECT_EQ(lammps_get_thermo(lmp, "step"), 2);
+    EXPECT_EQ(lammps_get_thermo(lmp, "atoms"), 29);
+    EXPECT_DOUBLE_EQ(lammps_get_thermo(lmp, "vol"), 3375.0);
+    EXPECT_DOUBLE_EQ(lammps_get_thermo(lmp, "density"), 0.12211250945013695);
+    EXPECT_DOUBLE_EQ(lammps_get_thermo(lmp, "cellalpha"), 90.0);
 };

unittest/c-library/test_main.cpp

@@ -0,0 +1,59 @@
+/* ----------------------------------------------------------------------
+   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 "test_main.h"
+#include "utils.h"
+#include "gmock/gmock.h"
+#include "gtest/gtest.h"
+
+#include <iostream>
+#include <mpi.h>
+
+// whether to print verbose output (i.e. not capturing LAMMPS screen output).
+bool verbose = false;
+
+int main(int argc, char **argv)
+{
+    MPI_Init(&argc, &argv);
+    ::testing::InitGoogleMock(&argc, argv);
+
+    if (argc < 1) {
+        return 1;
+    }
+
+    // handle arguments passed via environment variable
+    if (const char *var = getenv("TEST_ARGS")) {
+        std::vector<std::string> env = LAMMPS_NS::utils::split_words(var);
+        for (auto arg : env) {
+            if (arg == "-v") {
+                verbose = true;
+            }
+        }
+    }
+
+    int iarg = 1;
+    while (iarg < argc) {
+        if (strcmp(argv[iarg], "-v") == 0) {
+            verbose = true;
+            ++iarg;
+        } else {
+            std::cerr << "unknown option: " << argv[iarg] << "\n\n";
+            MPI_Finalize();
+            return 1;
+        }
+    }
+
+    int rv = RUN_ALL_TESTS();
+    MPI_Finalize();
+    return rv;
+}

unittest/c-library/test_main.h

@@ -0,0 +1,33 @@
+/* -*- c++ -*- ----------------------------------------------------------
+   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.
+------------------------------------------------------------------------- */
+
+#ifndef TEST_MAIN_H
+#define TEST_MAIN_H
+
+extern bool verbose;
+
+#define EXPECT_FP_LE_WITH_EPS(val1, val2, eps)                \
+    do {                                                      \
+        const double diff = fabs(val1 - val2);                \
+        const double div  = std::min(fabs(val1), fabs(val2)); \
+        const double err  = (div == 0.0) ? diff : diff / div; \
+        EXPECT_PRED_FORMAT2(::testing::DoubleLE, err, eps);   \
+    } while (0);
+
+#endif
+
+#if defined _WIN32
+static const char PATH_SEP = '\\';
+#else
+static const char PATH_SEP = '/';
+#endif