class TestThemeManager(TestCase): """ Test the functions in the ThemeManager Class """ def setUp(self): with patch('openlp.core.ui.ThemeForm._setup'): self.instance = ThemeForm(None) def test_on_image_path_edit_path_changed(self): """ Test the `image_path_edit.pathChanged` handler """ # GIVEN: An instance of Theme Form with patch.object(self.instance, 'set_background_page_values' ) as mocked_set_background_page_values: self.instance.theme = MagicMock() # WHEN: `on_image_path_edit_path_changed` is clicked self.instance.on_image_path_edit_path_changed( Path('/', 'new', 'pat.h')) # THEN: The theme background file should be set and `set_background_page_values` should have been called assert self.instance.theme.background_filename == Path( '/', 'new', 'pat.h') mocked_set_background_page_values.assert_called_once_with()