def test_notify_raises_if_command_unknown(self):
'''
Test that an exception is thrown if notify is called with a command it does not recognise.
'''
fl_presenter = FileLoaderPresenter(self.mock_view)
# Create a fake command/enum
fake_enum = Enum(value='invalid', names=[('bad_command', -200000)])
with self.assertRaises(ValueError):
fl_presenter.notify(fake_enum.bad_command)
def __init__(self, parent=None):
QAction.__init__(self, parent, text="Open...")
self.parent = parent
# Placeholder for the filename
self.fname = None
# Action for opening a file
self.triggered.connect(self.open_file)
self._presenter = FileLoaderPresenter(self)
def test_closing_filedialog_does_nothing(self):
'''
Test that closing the FileDialog without choosing a file causes the presenter to return without attempting
to open/interpret a file.
'''
mock_view = mock.create_autospec(FileLoaderViewInterface)
'''
Tell the mock FileLoaderView to behave as if the FileDialog was closed without a file being chosen by returning
an empty "filename"
'''
mock_view.get_selected_file_path = mock.MagicMock(side_effect = lambda: ('',''))
fl_presenter = FileLoaderPresenter(mock_view)
fl_presenter.register_master(self.mock_main_presenter)
# Mock the `_load_data` method to check its calls
fl_presenter._load_data = mock.MagicMock()
fl_presenter.notify(Command.FILEOPENREQUEST)
# Check that the `_load_data` and `set_dict` methods were not called due to a file not being selected
fl_presenter._load_data.assert_not_called()
self.mock_main_presenter.set_dict.assert_not_called()
class FileLoaderWidget(QAction, FileLoaderViewInterface):
def __init__(self, parent=None):
QAction.__init__(self, parent, text="Open...")
self.parent = parent
# Placeholder for the filename
self.fname = None
# Action for opening a file
self.triggered.connect(self.open_file)
self._presenter = FileLoaderPresenter(self)
def get_selected_file_path(self):
return self.fname
def show_reject_file_message(self, error_msg):
'''
Error message displayed when the chosen file couldn't be read into an xarray. Simply a copy of the exception
thrown during file reading.
'''
error_dialog = QErrorMessage()
error_dialog.showMessage(error_msg)
error_dialog.exec_()
def open_file(self):
# Create and show a file dialog with a NetCDF filter
filedialog = QFileDialog()
# Store the location of the file that was selected
self.fname = filedialog.getOpenFileName(self.parent, "Open file",
"/home", "NetCDF (*.nc)")
# Inform the presenter that the user attempted to open a file
self._presenter.notify(Command.FILEOPENREQUEST)
def get_presenter(self):
return self._presenter
def test_bad_file_shows_message_on_view(self):
'''
Test that the request to open a bad file causes the view to display a message.
'''
fl_presenter = FileLoaderPresenter(self.mock_view)
fl_presenter.register_master(self.mock_main_presenter)
# Mock the `open_dataset` function in the FileLoaderTool so that it returns a bad dataset
with mock.patch("datasetviewer.fileloader.FileLoaderTool.open_dataset",
side_effect=lambda path: self.empty_data):
fl_presenter.notify(Command.FILEOPENREQUEST)
'''
Check that loading a bad dataset caused a message to be displayed on the view indicating that the file
was rejected.
'''
self.mock_view.show_reject_file_message.assert_called_once()
'''
Check that the `set_dict` method in the MainViewPresenter was not called as a result of the file being
rejected.
'''
self.mock_main_presenter.set_dict.assert_not_called()
def test_file_selection_calls_get_path_on_view(self):
'''
Test that a FILEOPENREQUEST in the FileLoaderPresenter's `notify` function causes the `get_selected_file_path`
method on the FileLoaderView to be called.
'''
fl_presenter = FileLoaderPresenter(self.mock_view)
fl_presenter.register_master(self.mock_main_presenter)
# Mock the `_load_data` method so that no actual file-reading occurs
fl_presenter._load_data = mock.MagicMock()
# Notify the FileLoaderPresenter of a FILE
fl_presenter.notify(Command.FILEOPENREQUEST)
self.mock_view.get_selected_file_path.assert_called_once()
def test_load_file(self):
'''
Test that a FILEOPENREQUEST in `notify` causes the `_load_data` method to be called with the expected argument.
'''
fl_presenter = FileLoaderPresenter(self.mock_view)
fl_presenter.register_master(self.mock_main_presenter)
# Mock the `_load_data` method
fl_presenter._load_data = mock.MagicMock()
fl_presenter.notify(Command.FILEOPENREQUEST)
'''
Check that the `_load_data` method was called with the first element from the filename-extension tuple that gets
returned by the FileLoaderView.
'''
fl_presenter._load_data.assert_called_once_with(self.fake_file_path[0])
def test_file_open_success_informs_main_presenter(self):
'''
Test that successfully opening a file in the FileLoaderPresenter causes the resulting DataSet to be sent to the
MainViewPresenter.
'''
fl_presenter = FileLoaderPresenter(self.mock_view)
fl_presenter.register_master(self.mock_main_presenter)
# Mock the `file_to_dict` function from the FileLoaderTool and make it return a fake dictionary
with mock.patch("datasetviewer.fileloader.FileLoaderTool.file_to_dict",
side_effect = lambda path: self.empty_dict):
fl_presenter.notify(Command.FILEOPENREQUEST)
# Check that the `set_dict` function in the MainViewPresenter was called with the same dictionary
self.mock_main_presenter.set_dict.assert_called_once_with(self.empty_dict)
def test_presenter_throws_if_view_none(self):
'''
Test that the FileLoaderPresenter throws an Exception when the FileLoaderView is None.
'''
with self.assertRaises(ValueError):
FileLoaderPresenter(None)