diff --git a/unittest/commands/CMakeLists.txt b/unittest/commands/CMakeLists.txt
index deeee00f71..297bd11054 100644
--- a/unittest/commands/CMakeLists.txt
+++ b/unittest/commands/CMakeLists.txt
@@ -29,6 +29,10 @@ add_executable(test_delete_atoms test_delete_atoms.cpp)
 target_link_libraries(test_delete_atoms PRIVATE lammps GTest::GMock)
 add_test(NAME DeleteAtoms COMMAND test_delete_atoms)
 
+add_executable(test_set_property test_set_property.cpp)
+target_link_libraries(test_set_property PRIVATE lammps GTest::GMock)
+add_test(NAME SetProperty COMMAND test_set_property)
+
 add_executable(test_variables test_variables.cpp)
 target_link_libraries(test_variables PRIVATE lammps GTest::GMock)
 add_test(NAME Variables COMMAND test_variables)
diff --git a/unittest/commands/test_set_property.cpp b/unittest/commands/test_set_property.cpp
new file mode 100644
index 0000000000..7803c99d5f
--- /dev/null
+++ b/unittest/commands/test_set_property.cpp
@@ -0,0 +1,193 @@
+/* ----------------------------------------------------------------------
+   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 "lammps.h"
+
+#include "atom.h"
+#include "compute.h"
+#include "domain.h"
+#include "math_const.h"
+
+#include "../testing/core.h"
+#include "gmock/gmock.h"
+#include "gtest/gtest.h"
+
+// whether to print verbose output (i.e. not capturing LAMMPS screen output).
+bool verbose = false;
+
+using LAMMPS_NS::MathConst::MY_PI;
+using LAMMPS_NS::utils::split_words;
+
+namespace LAMMPS_NS {
+using ::testing::ContainsRegex;
+using ::testing::ExitedWithCode;
+using ::testing::StrEq;
+
+class SetTest : public LAMMPSTest {
+protected:
+    Atom *atom;
+    Domain *domain;
+    void SetUp() override
+    {
+        testbinary = "SetTest";
+        args       = {"-log", "none", "-echo", "screen", "-nocite", "-v", "num", "1"};
+        LAMMPSTest::SetUp();
+        atom   = lmp->atom;
+        domain = lmp->domain;
+    }
+
+    void TearDown() override { LAMMPSTest::TearDown(); }
+
+    void atomic_system(const std::string &atom_style, const std::string units = "real")
+    {
+        BEGIN_HIDE_OUTPUT();
+        command("atom_style " + atom_style);
+        command("atom_modify map array");
+        command("units " + units);
+        command("lattice sc 1.0 origin 0.125 0.125 0.125");
+        command("region box block 0 2 0 2 0 2");
+        command("create_box 8 box");
+        command("create_atoms 1 box");
+        command("mass * 1.0");
+        command("region left block 0.0 1.0 INF INF INF INF");
+        command("region right block 1.0 2.0 INF INF INF INF");
+        command("region top block INF INF 0.0 1.0 INF INF");
+        command("region bottom block INF INF 1.0 2.0 INF INF");
+        command("region front block INF INF INF INF 0.0 1.0");
+        command("region back block INF INF INF 1.0 2.0 INF");
+        command("group top region top");
+        command("group bottom region bottom");
+        END_HIDE_OUTPUT();
+    }
+};
+
+TEST_F(SetTest, NoBoxNoAtoms)
+{
+    ASSERT_EQ(atom->natoms, 0);
+    ASSERT_EQ(domain->box_exist, 0);
+    TEST_FAILURE(".*ERROR: Set command before simulation box is.*", command("set type 1 x 0.0"););
+
+    BEGIN_HIDE_OUTPUT();
+    command("region box block 0 2 0 2 0 2");
+    command("create_box 1 box");
+    END_HIDE_OUTPUT();
+    TEST_FAILURE(".*ERROR: Set command on system without atoms.*", command("set type 1 x 0.0"););
+
+    BEGIN_HIDE_OUTPUT();
+    command("create_atoms 1 single 0.5 0.5 0.5");
+    END_HIDE_OUTPUT();
+    TEST_FAILURE(".*ERROR: Illegal set command: need at least four.*", command("set type 1 x"););
+    TEST_FAILURE(".*ERROR: Unknown set command style: xxx.*", command("set xxx 1 x 0.0"););
+    TEST_FAILURE(".*ERROR: Set keyword or custom property yyy does not exist.*",
+                 command("set type 1 yyy 0.0"););
+}
+
+TEST_F(SetTest, StylesTypes)
+{
+    atomic_system("molecular");
+    ASSERT_EQ(atom->natoms, 8);
+
+    BEGIN_HIDE_OUTPUT();
+    command("set group all mol 1");
+    command("set group top type 2");
+    command("set region back type 3");
+    command("set region left mol 2");
+    END_HIDE_OUTPUT();
+    ASSERT_EQ(atom->type[0], 2);
+    ASSERT_EQ(atom->type[1], 2);
+    ASSERT_EQ(atom->type[2], 1);
+    ASSERT_EQ(atom->type[3], 1);
+    ASSERT_EQ(atom->type[4], 2);
+    ASSERT_EQ(atom->type[5], 2);
+    ASSERT_EQ(atom->type[6], 1);
+    ASSERT_EQ(atom->type[7], 1);
+
+    BEGIN_HIDE_OUTPUT();
+    command("set mol 1 type 4");
+    command("set atom 4*7 type 5");
+    END_HIDE_OUTPUT();
+    ASSERT_EQ(atom->type[0], 2);
+    ASSERT_EQ(atom->type[1], 4);
+    ASSERT_EQ(atom->type[2], 1);
+    ASSERT_EQ(atom->type[3], 5);
+    ASSERT_EQ(atom->type[4], 5);
+    ASSERT_EQ(atom->type[5], 5);
+    ASSERT_EQ(atom->type[6], 5);
+    ASSERT_EQ(atom->type[7], 4);
+
+    BEGIN_HIDE_OUTPUT();
+    command("variable rev atom 9-id");
+    command("set group all type v_rev");
+    END_HIDE_OUTPUT();
+    ASSERT_EQ(atom->type[0], 8);
+    ASSERT_EQ(atom->type[1], 7);
+    ASSERT_EQ(atom->type[2], 6);
+    ASSERT_EQ(atom->type[3], 5);
+    ASSERT_EQ(atom->type[4], 4);
+    ASSERT_EQ(atom->type[5], 3);
+    ASSERT_EQ(atom->type[6], 2);
+    ASSERT_EQ(atom->type[7], 1);
+
+    BEGIN_HIDE_OUTPUT();
+    command("set group all type 1");
+    command("set group all type/fraction 2 0.5 453246");
+    END_HIDE_OUTPUT();
+    int sum = 0;
+    for (int i = 0; i < 8; ++i)
+        sum += (atom->type[i] == 2) ? 1 : 0;
+    ASSERT_EQ(sum, 4);
+
+    BEGIN_HIDE_OUTPUT();
+    command("set group all type 1");
+    command("set group all type/ratio 2 0.5 5784536");
+    END_HIDE_OUTPUT();
+    sum = 0;
+    for (int i = 0; i < 8; ++i)
+        sum += (atom->type[i] == 2) ? 1 : 0;
+    ASSERT_EQ(sum, 4);
+
+    BEGIN_HIDE_OUTPUT();
+    command("set group all type 1");
+    command("set group all type/subset 2 4 784536");
+    END_HIDE_OUTPUT();
+    sum = 0;
+    for (int i = 0; i < 8; ++i)
+        sum += (atom->type[i] == 2) ? 1 : 0;
+    ASSERT_EQ(sum, 4);
+}
+} // 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;
+}