Live Viewer local eyes tests cant be run independently

[MikeSullivan7]

Summary

When attempting to run the Live Viewer eyes tests locally without running other eyes tests, the tests fail due to the fake file system.

Steps To Reproduce

In either Linux or Windows, run make test-screenshots or make tests-screenshots-win where the directory to search for tests is set to the live viewer tests. I.e. edit the Makefile such that:

test-screenshots:
	-mkdir ${TEST_RESULT_DIR}
	APPLITOOLS_API_KEY=local APPLITOOLS_IMAGE_DIR=${TEST_RESULT_DIR} ${XVFBRUN} pytest -p no:xdist -p no:randomly -p no:cov mantidimaging/eyes_tests/live_viewer_windows_test.py -vs --run-eyes-tests
	@echo "Screenshots writen to" ${TEST_RESULT_DIR}

or

test-screenshots-win:
	-mkdir ${TEST_RESULT_DIR}
	${XVFBRUN} pytest -p no:xdist -p no:randomly -p no:cov mantidimaging/eyes_tests/live_viewer_window_test.py -vs --run-eyes-tests
	@echo "Screenshots writen to" ${TEST_RESULT_DIR}

Then run make test-screenshots or make tests-screenshots-win.

Current Behaviour

All tests fail

Expected Behaviour

Live Viewer eyes tests should be able to run independent of the other eyes tests. This way we don't have to run all eyes tests just to test the Live Viewer.

Failure Logs

(mantidimaging-dev) C:\Users\ddb29996\mantidimaging>make test-screenshots-win
mkdir C:\Users\ddb29996\AppData\Local\Temp\mantidimaging_tests
A subdirectory or file C:\Users\ddb29996\AppData\Local\Temp\mantidimaging_tests already exists.
make: [Makefile:60: test-screenshots-win] Error 1 (ignored)
pytest -p no:xdist -p no:randomly -p no:cov mantidimaging/eyes_tests/live_viewer_window_test.py -vs --run-eyes-tests
======================================================= test session starts =======================================================
platform win32 -- Python 3.12.8, pytest-7.4.4, pluggy-1.5.0 -- C:\Users\ddb29996\AppData\Local\miniforge3\envs\mantidimaging-dev\python.exe
cachedir: .pytest_cache
rootdir: C:\Users\ddb29996\mantidimaging
plugins: pyfakefs-5.3.5, xdist-3.3.1
collected 4 items

mantidimaging/eyes_tests/live_viewer_window_test.py::LiveViewerWindowTest::test_live_view_opens_with_bad_data (node:33812) ExperimentalWarning: Module._stat is an experimental feature and might change at any time
(Use `core --trace-warnings ...` to show where the warning was created)
(node:33812) ExperimentalWarning: Module._readPackage is an experimental feature and might change at any time
FAILED
mantidimaging/eyes_tests/live_viewer_window_test.py::LiveViewerWindowTest::test_live_view_opens_with_data FAILED
mantidimaging/eyes_tests/live_viewer_window_test.py::LiveViewerWindowTest::test_live_view_opens_without_data FAILED
mantidimaging/eyes_tests/live_viewer_window_test.py::LiveViewerWindowTest::test_rotate_operation_rotates_image FAILED

============================================================ FAILURES =============================================================
_____________________________________ LiveViewerWindowTest.test_live_view_opens_with_bad_data _____________________________________

self = <mantidimaging.eyes_tests.live_viewer_window_test.LiveViewerWindowTest testMethod=test_live_view_opens_with_bad_data>
_mock_time = <MagicMock name='time' id='2438838525088'>, _mock_image_watcher = <MagicMock name='ImageWatcher' id='2438838529552'>
mock_load_image = <MagicMock name='load_image_from_path' id='2438838533200'>

    @mock.patch('mantidimaging.gui.windows.live_viewer.presenter.LiveViewerWindowPresenter.load_image_from_path')
    @mock.patch('mantidimaging.gui.windows.live_viewer.model.ImageWatcher')
    @mock.patch("time.time", return_value=4000.0)
    def test_live_view_opens_with_bad_data(self, _mock_time, _mock_image_watcher, mock_load_image):
        file_list = self._make_simple_dir(self.live_directory)
        image_list = [Image_Data(path) for path in file_list]
        mock_load_image.side_effect = ValueError
>       self.imaging.show_live_viewer(self.live_directory)

mantidimaging\eyes_tests\live_viewer_window_test.py:77:
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _
mantidimaging\gui\windows\main\view.py:452: in show_live_viewer
    live_viewer = LiveViewerWindowView(self, live_data_path)
mantidimaging\gui\windows\live_viewer\view.py:37: in __init__
    self.live_viewer = LiveViewWidget()
mantidimaging\gui\windows\live_viewer\live_view_widget.py:32: in __init__
    self.image = MIMiniImageView(name="Projection")
mantidimaging\gui\widgets\mi_mini_image_view\view.py:50: in __init__
    self.hist = HistogramLUTItem(self.im)
..\AppData\Local\miniforge3\envs\mantidimaging-dev\Lib\site-packages\pyqtgraph\graphicsItems\HistogramLUTItem.py:117: in __init__
    self.gradient = GradientEditorItem(orientation=self.gradientPosition)
..\AppData\Local\miniforge3\envs\mantidimaging-dev\Lib\site-packages\pyqtgraph\graphicsItems\GradientEditorItem.py:440: in __init__
    self.menu = ColorMapMenu(showGradientSubMenu=True, showColorMapSubMenus=True)
..\AppData\Local\miniforge3\envs\mantidimaging-dev\Lib\site-packages\pyqtgraph\widgets\ColorMapMenu.py:199: in __init__
    if find_mpl_leftovers():
..\AppData\Local\miniforge3\envs\mantidimaging-dev\Lib\site-packages\pyqtgraph\widgets\ColorMapMenu.py:78: in find_mpl_leftovers
    names = colormap.listMaps(source="matplotlib")
..\AppData\Local\miniforge3\envs\mantidimaging-dev\Lib\site-packages\pyqtgraph\colormap.py:42: in listMaps
    import matplotlib.pyplot as mpl_plt
..\AppData\Local\miniforge3\envs\mantidimaging-dev\Lib\site-packages\matplotlib\__init__.py:997: in <module>
    rcParamsDefault = _rc_params_in_file(
..\AppData\Local\miniforge3\envs\mantidimaging-dev\Lib\site-packages\matplotlib\__init__.py:903: in _rc_params_in_file
    with _open_file_or_url(fname) as fd:
..\AppData\Local\miniforge3\envs\mantidimaging-dev\Lib\contextlib.py:137: in __enter__
    return next(self.gen)
..\AppData\Local\miniforge3\envs\mantidimaging-dev\Lib\site-packages\matplotlib\__init__.py:880: in _open_file_or_url
    with open(fname, encoding='utf-8') as f:
..\AppData\Local\miniforge3\envs\mantidimaging-dev\Lib\site-packages\pyfakefs\fake_io.py:125: in open
    return fake_open(
..\AppData\Local\miniforge3\envs\mantidimaging-dev\Lib\site-packages\pyfakefs\fake_open.py:97: in __call__
    return self.call(*args, **kwargs)
..\AppData\Local\miniforge3\envs\mantidimaging-dev\Lib\site-packages\pyfakefs\fake_open.py:199: in call
    file_object = self._init_file_object(
..\AppData\Local\miniforge3\envs\mantidimaging-dev\Lib\site-packages\pyfakefs\fake_open.py:282: in _init_file_object
    self.filesystem.raise_os_error(errno.ENOENT, file_path)
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _

self = <pyfakefs.fake_filesystem.FakeFilesystem object at 0x00000237D4BE04A0>, err_no = 2
filename = 'C:\\Users\\ddb29996\\AppData\\Local\\miniforge3\\envs\\mantidimaging-dev\\Lib\\site-packages\\matplotlib\\mpl-data\\matplotlibrc'
winerror = None

    def raise_os_error(
        self,
        err_no: int,
        filename: Optional[AnyString] = None,
        winerror: Optional[int] = None,
    ) -> NoReturn:
        """Raises OSError.
        The error message is constructed from the given error code and shall
        start with the error string issued in the real system.
        Note: this is not true under Windows if winerror is given - in this
        case a localized message specific to winerror will be shown in the
        real file system.

        Args:
            err_no: A numeric error code from the C variable errno.
            filename: The name of the affected file, if any.
            winerror: Windows only - the specific Windows error code.
        """
        message = os.strerror(err_no) + " in the fake filesystem"
        if winerror is not None and sys.platform == "win32" and self.is_windows_fs:
            raise OSError(err_no, message, filename, winerror)
>       raise OSError(err_no, message, filename)
E       FileNotFoundError: [Errno 2] No such file or directory in the fake filesystem: 'C:\\Users\\ddb29996\\AppData\\Local\\miniforge3\\envs\\mantidimaging-dev\\Lib\\site-packages\\matplotlib\\mpl-data\\matplotlibrc'

..\AppData\Local\miniforge3\envs\mantidimaging-dev\Lib\site-packages\pyfakefs\fake_filesystem.py:427: FileNotFoundError