add unittests

Author: GdoongMathew

tests/tests_pytorch/accelerators/test_mps.py

@@ -13,6 +13,7 @@
 # limitations under the License.
 
 from collections import namedtuple
+from subprocess import SubprocessError
 from unittest import mock
 
 import pytest
@@ -21,6 +22,7 @@
 import tests_pytorch.helpers.pipelines as tpipes
 from lightning.pytorch import Trainer
 from lightning.pytorch.accelerators import MPSAccelerator
+from lightning.pytorch.accelerators.mps import _get_mps_device_name
 from lightning.pytorch.demos.boring_classes import BoringModel
 from tests_pytorch.helpers.runif import RunIf
 
@@ -151,3 +153,21 @@ def to(self, *args, **kwargs):
 
     batch = trainer.strategy.batch_to_device(CustomBatchType(), torch.device("mps"))
     assert batch.a.type() == "torch.mps.FloatTensor"
+
+
+@mock.patch("lightning.pytorch.accelerators.mps.subprocess.run")
+def test_get_mps_device_name(mock_run):
+    mock_stdout = mock.MagicMock()
+    mock_stdout.configure_mock(stdout="Apple M1 Pro\n")
+
+    mock_run.return_value = mock_stdout
+    device_name = _get_mps_device_name()
+    assert device_name == "Apple M1 Pro"
+
+
+@mock.patch(
+    "lightning.pytorch.accelerators.mps.subprocess.run",
+    side_effect=SubprocessError("test"),
+)
+def test_get_mps_device_name_exception(mock_run):
+    assert _get_mps_device_name() == "True (mps)"