add unit tests

pytests/test_volumes.py

@@ -0,0 +1,19 @@
+import pytest
+
+from podman_compose import parse_short_mount
+
+@pytest.fixture
+def multi_propagation_mount_str():
+    return "/foo/bar:/baz:U,Z"
+
+
+def test_parse_short_mount_multi_propagation(multi_propagation_mount_str):
+    expected = {
+        "type": "bind",
+        "source": "/foo/bar",
+        "target": "/baz",
+        "bind": {
+            "propagation": "U,Z",
+        },
+    }
+    assert parse_short_mount(multi_propagation_mount_str, "/") == expected