Add tests for getting the data directory on different platforms

tests/config/test_configmanager.py

@@ -74,6 +74,26 @@ def test_unix_config_path():
     config_manager.delete_instance("testapp")
 
 
+@pytest.mark.skipif(platform.system() != "Windows", reason="Test specific to Windows platform")
+def test_windows_data_dir_path():
+    config_manager = ConfigManager(app_name="testapp")
+    data_dir = config_manager.get_data_dir_path()  # pylint: disable=protected-access
+    expected_data_dir = Path(os.getenv("LOCALAPPDATA", str(Path("~\\AppData\\Local").expanduser())))
+    assert expected_data_dir in data_dir.parents
+    # delete instance so other tests don't accidentally use it
+    config_manager.delete_instance("testapp")
+
+
+@pytest.mark.skipif(platform.system() == "Windows", reason="Test specific to Unix-like platforms")
+def test_unix_data_dir_path():
+    config_manager = ConfigManager(app_name="testapp")
+    data_dir = config_manager.get_data_dir_path()  # pylint: disable=protected-access
+    expected_data_dir = Path(os.getenv("XDG_DATA_HOME", str(Path("~/.local/share").expanduser())))
+    assert expected_data_dir in data_dir.parents
+    # delete instance so other tests don't accidentally use it
+    config_manager.delete_instance("testapp")
+
+
 def test_preserve_comments(config_manager):
     # Create a config file with some value and add in a comment line
     config_manager.set("Settings", "theme", "dark")