document and add unit tests for lammps_set_fix_external_callback()

2021-07-16 14:51:04 -04:00
parent 95792ac928
commit 88e363c0bb
6 changed files with 159 additions and 14 deletions
--- a/unittest/c-library/test_library_external.cpp
+++ b/unittest/c-library/test_library_external.cpp
@ -0,0 +1,73 @@
+// unit tests creating LAMMPS instances via the library interface
+
+#include "library.h"
+
+#include <cinttypes>
+#include <string>
+
+#include "gmock/gmock.h"
+#include "gtest/gtest.h"
+
+#include "test_main.h"
+
+using ::testing::HasSubstr;
+using ::testing::StartsWith;
+
+extern "C" {
+#ifdef LAMMPS_SMALLSMALL
+typedef int32_t step_t;
+typedef int32_t tag_t;
+#elif LAMMPS_SMALLBIG
+typedef int64_t step_t;
+typedef int32_t tag_t;
+#else
+typedef int64_t step_t;
+typedef int64_t tag_t;
+#endif
+static void callback_one(void *lmp, step_t timestep, int nlocal, tag_t *ids, double **x, double **f)
+{
+    for (int i = 0; i < nlocal; ++i)
+        f[i][0] = f[i][1] = f[i][2] = (double)timestep;
+}
+}
+
+TEST(lammps_external_pf, null_args)
+{
+    const char *args[] = {"liblammps", "-log", "none", "-nocite"};
+    char **argv        = (char **)args;
+    int argc           = sizeof(args) / sizeof(char *);
+
+    ::testing::internal::CaptureStdout();
+    void *handle       = lammps_open_no_mpi(argc, argv, NULL);
+    std::string output = ::testing::internal::GetCapturedStdout();
+    if (verbose) std::cout << output;
+
+    ::testing::internal::CaptureStdout();
+    lammps_commands_string(handle, "lattice sc 1.0\n"
+                                   "region box block -1 1 -1 1 -1 1\n"
+                                   "create_box 1 box\n"
+                                   "create_atoms 1 box\n"
+                                   "mass 1 1.0\n"
+                                   "pair_style zero 0.1\n"
+                                   "pair_coeff 1 1\n"
+                                   "velocity all set 0.1 0.0 -0.1\n"
+                                   "thermo 5\n"
+                                   "fix 1 all nve\n"
+                                   "fix ext all external pf/callback 5 1\n");
+
+    output = ::testing::internal::GetCapturedStdout();
+    if (verbose) std::cout << output;
+
+    ::testing::internal::CaptureStdout();
+    lammps_set_fix_external_callback(handle, (char *)"ext", &callback_one, handle);
+    lammps_command(handle, "run 10 post no");
+    double temp = lammps_get_thermo(handle,"temp");
+    output = ::testing::internal::GetCapturedStdout();
+    if (verbose) std::cout << output;
+    EXPECT_DOUBLE_EQ(temp,1.0/30.0);
+
+    ::testing::internal::CaptureStdout();
+    lammps_close(handle);
+    output = ::testing::internal::GetCapturedStdout();
+    if (verbose) std::cout << output;
+}