diff --git a/dpnp/tests/test_ndarray.py b/dpnp/tests/test_ndarray.py
index 0a394c291585..dd790c8e56a1 100644
--- a/dpnp/tests/test_ndarray.py
+++ b/dpnp/tests/test_ndarray.py
@@ -460,3 +460,29 @@ def test_clip():
     expected = numpy.clip(numpy_array, 3, 7)
 
     assert_array_equal(expected, result)
+
+
+def test_rmatmul_dpnp_array():
+    a = dpnp.ones(10)
+    b = dpnp.ones(10)
+
+    class Dummy(dpnp.ndarray):
+        def __init__(self, x):
+            self._array_obj = x.get_array()
+
+        def __matmul__(self, other):
+            return NotImplemented
+
+    d = Dummy(a)
+
+    result = d @ b
+    expected = a @ b
+    assert (result == expected).all()
+
+
+def test_rmatmul_numpy_array():
+    a = dpnp.ones(10)
+    b = numpy.ones(10)
+
+    with pytest.raises(TypeError):
+        b @ a
diff --git a/dpnp/tests/test_utils.py b/dpnp/tests/test_utils.py
new file mode 100644
index 000000000000..89e97b75d5e5
--- /dev/null
+++ b/dpnp/tests/test_utils.py
@@ -0,0 +1,69 @@
+import dpctl
+import dpctl.tensor as dpt
+import numpy
+import pytest
+
+import dpnp
+
+
+class TestIsSupportedArrayOrScalar:
+    @pytest.mark.parametrize(
+        "array",
+        [
+            dpnp.array([1, 2, 3]),
+            dpnp.array(1),
+            dpt.asarray([1, 2, 3]),
+        ],
+    )
+    def test_valid_arrays(self, array):
+        assert dpnp.is_supported_array_or_scalar(array) is True
+
+    @pytest.mark.parametrize(
+        "value",
+        [
+            42,
+            True,
+            "1",
+        ],
+    )
+    def test_valid_scalars(self, value):
+        assert dpnp.is_supported_array_or_scalar(value) is True
+
+    @pytest.mark.parametrize(
+        "array",
+        [
+            [1, 2, 3],
+            (1, 2, 3),
+            None,
+            numpy.array([1, 2, 3]),
+        ],
+    )
+    def test_invalid_arrays(self, array):
+        assert not dpnp.is_supported_array_or_scalar(array) is True
+
+
+class TestSynchronizeArrayData:
+    @pytest.mark.parametrize(
+        "array",
+        [
+            dpnp.array([1, 2, 3]),
+            dpt.asarray([1, 2, 3]),
+        ],
+    )
+    def test_synchronize_array_data(self, array):
+        a_copy = dpnp.copy(array, sycl_queue=array.sycl_queue)
+        try:
+            dpnp.synchronize_array_data(a_copy)
+        except Exception as e:
+            pytest.fail(f"synchronize_array_data failed: {e}")
+
+    @pytest.mark.parametrize(
+        "input",
+        [
+            [1, 2, 3],
+            numpy.array([1, 2, 3]),
+        ],
+    )
+    def test_unsupported_type(self, input):
+        with pytest.raises(TypeError):
+            dpnp.synchronize_array_data(input)