openlp/tests/openlp_core/widgets/test_widgets.py
2022-02-06 09:10:17 +00:00

629 lines
26 KiB
Python

# -*- coding: utf-8 -*-
##########################################################################
# OpenLP - Open Source Lyrics Projection #
# ---------------------------------------------------------------------- #
# Copyright (c) 2008-2022 OpenLP Developers #
# ---------------------------------------------------------------------- #
# This program is free software: you can redistribute it and/or modify #
# it under the terms of the GNU General Public License as published by #
# the Free Software Foundation, either version 3 of the License, or #
# (at your option) any later version. #
# #
# This program is distributed in the hope that it will be useful, #
# but WITHOUT ANY WARRANTY; without even the implied warranty of #
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the #
# GNU General Public License for more details. #
# #
# You should have received a copy of the GNU General Public License #
# along with this program. If not, see <https://www.gnu.org/licenses/>. #
##########################################################################
"""
Package to test the screens tab functionality (primarily ScreenSelectionWidget and ScreenButton classes)
within openlp/core/widgets/widgets.py
"""
import pytest
from unittest.mock import MagicMock, call, patch
from PyQt5 import QtCore, QtWidgets, QtTest
from openlp.core.common.settings import ProxyMode
from openlp.core.display.screens import Screen
from openlp.core.widgets.widgets import ProxyWidget, ProxyDialog, ScreenButton, ScreenSelectionWidget
@pytest.fixture()
def form(settings):
test_form = ScreenSelectionWidget()
return test_form
def mocked_screens(custom_geometry):
screen0 = MagicMock()
screen0.number = 0
screen0.is_display = True
screen0.is_primary = False
screen0.geometry = QtCore.QRect(-271, -1080, 1920, 1080)
screen0.custom_geometry = custom_geometry
screen0.__str__.return_value = "Screen 1"
screen1 = MagicMock()
screen1.number = 1
screen1.is_display = False
screen1.is_primary = True
screen1.geometry = QtCore.QRect(0, 0, 1366, 768)
screen1.custom_geometry = custom_geometry
screen1.__str__.return_value = "Screen 2"
return [screen0, screen1]
@patch('openlp.core.display.screens.ScreenList')
def test_screen_buttons_show_pixels(mocked_screenList, form):
'''
Test that the screen buttons show the screen sizes in pixels
'''
# GIVEN: A mocked extended desktop configuration
mocked_screenList.return_value = mocked_screens(None)
form.screens = mocked_screenList()
# WHEN: When I go into screen settings for the display screen
ScreenSelectionWidget.load(form)
# THEN: The screen buttons should show the correct size of that screen
screen_0_button = form.findChild(QtWidgets.QPushButton, 'screen_0_button')
screen_1_button = form.findChild(QtWidgets.QPushButton, 'screen_1_button')
assert '1920' in str(screen_0_button.text())
assert '1080' in str(screen_0_button.text())
assert '1366' in str(screen_1_button.text())
assert '768' in str(screen_1_button.text())
@patch('openlp.core.display.screens.ScreenList')
def test_spinboxes_no_previous_custom_geometry(mocked_screenList, form):
"""
Test screen custom geometry can be changed from None
"""
# GIVEN: A mocked extended desktop configuration
mocked_screenList.return_value = mocked_screens(None)
form.screens = mocked_screenList()
# WHEN: When I go into screen settings for the display screen and set the custom geometry
ScreenSelectionWidget.load(form)
QtTest.QTest.mouseClick(form.custom_geometry_button, QtCore.Qt.LeftButton)
QtTest.QTest.keyClick(form.left_spin_box, QtCore.Qt.Key_Up)
QtTest.QTest.keyClick(form.top_spin_box, QtCore.Qt.Key_Up)
QtTest.QTest.keyClick(form.width_spin_box, QtCore.Qt.Key_Down)
QtTest.QTest.keyClick(form.height_spin_box, QtCore.Qt.Key_Down)
# THEN: The spin boxes should show the correct values
assert form.left_spin_box.value() == 1
assert form.top_spin_box.value() == 1
assert form.width_spin_box.value() == 1919
assert form.height_spin_box.value() == 1079
@patch('openlp.core.display.screens.ScreenList')
def test_spinboxes_with_previous_custom_geometry(mocked_screenList, form):
"""
Test screen existing custom geometry can be changed
"""
# GIVEN: A mocked extended desktop configuration
testGeometry = QtCore.QRect(1, 1, 1919, 1079)
mocked_screenList.return_value = mocked_screens(testGeometry)
form.screens = mocked_screenList()
# WHEN: When I go into screen settings for the display screen and update the custom geometry
ScreenSelectionWidget.load(form)
QtTest.QTest.mouseClick(form.custom_geometry_button, QtCore.Qt.LeftButton)
QtTest.QTest.keyClick(form.left_spin_box, QtCore.Qt.Key_Up)
QtTest.QTest.keyClick(form.top_spin_box, QtCore.Qt.Key_Up)
QtTest.QTest.keyClick(form.width_spin_box, QtCore.Qt.Key_Down)
QtTest.QTest.keyClick(form.height_spin_box, QtCore.Qt.Key_Down)
# THEN: The spin boxes should show the updated values
assert form.left_spin_box.value() == 2
assert form.top_spin_box.value() == 2
assert form.width_spin_box.value() == 1918
assert form.height_spin_box.value() == 1078
@patch('openlp.core.display.screens.ScreenList')
def test_spinboxes_going_outside_screen_geometry(mocked_screenList, form):
"""
Test screen existing custom geometry can be increased beyond the bounds of the screen
"""
# GIVEN: A mocked extended desktop configuration
testGeometry = QtCore.QRect(1, 1, 1919, 1079)
mocked_screenList.return_value = mocked_screens(testGeometry)
form.screens = mocked_screenList()
# WHEN: When I go into screen settings for the display screen and
# update the custom geometry to be outside the screen coordinates
ScreenSelectionWidget.load(form)
QtTest.QTest.mouseClick(form.custom_geometry_button, QtCore.Qt.LeftButton)
for _ in range(2):
QtTest.QTest.keyClick(form.left_spin_box, QtCore.Qt.Key_Down)
QtTest.QTest.keyClick(form.top_spin_box, QtCore.Qt.Key_Down)
QtTest.QTest.keyClick(form.width_spin_box, QtCore.Qt.Key_Up)
QtTest.QTest.keyClick(form.height_spin_box, QtCore.Qt.Key_Up)
# THEN: The spin boxes should show the updated values
assert form.left_spin_box.value() == -1
assert form.top_spin_box.value() == -1
assert form.width_spin_box.value() == 1921
assert form.height_spin_box.value() == 1081
def test_radio_button_exclusivity_no_proxy(settings):
"""
Test that only one radio button can be checked at a time, and that the line edits are only enabled when the
`manual_proxy_radio` is checked
"""
# GIVEN: An instance of the `openlp.core.common.widgets.widgets.ProxyWidget` with a radio already checked
proxy_widget = ProxyWidget()
proxy_widget.manual_proxy_radio.setChecked(True)
# WHEN: 'Checking' the `no_proxy_radio` button
proxy_widget.no_proxy_radio.setChecked(True)
# THEN: The other radio buttons should not be checked and the line edits should not be enabled
assert proxy_widget.use_sysem_proxy_radio.isChecked() is False
assert proxy_widget.manual_proxy_radio.isChecked() is False
assert proxy_widget.http_edit.isEnabled() is False
assert proxy_widget.https_edit.isEnabled() is False
assert proxy_widget.username_edit.isEnabled() is False
assert proxy_widget.password_edit.isEnabled() is False
def test_radio_button_exclusivity_system_proxy(settings):
"""
Test that only one radio button can be checked at a time, and that the line edits are only enabled when the
`manual_proxy_radio` is checked
"""
# GIVEN: An instance of the `openlp.core.common.widgets.widgets.ProxyWidget` with a radio already checked
proxy_widget = ProxyWidget()
proxy_widget.manual_proxy_radio.setChecked(True)
# WHEN: 'Checking' the `use_sysem_proxy_radio` button
proxy_widget.use_sysem_proxy_radio.setChecked(True)
# THEN: The other radio buttons should not be checked and the line edits should not be enabled
assert proxy_widget.no_proxy_radio.isChecked() is False
assert proxy_widget.manual_proxy_radio.isChecked() is False
assert proxy_widget.http_edit.isEnabled() is False
assert proxy_widget.https_edit.isEnabled() is False
assert proxy_widget.username_edit.isEnabled() is False
assert proxy_widget.password_edit.isEnabled() is False
def test_radio_button_exclusivity_manual_proxy(settings):
"""
Test that only one radio button can be checked at a time, and that the line edits are only enabled when the
`manual_proxy_radio` is checked
"""
# GIVEN: An instance of the `openlp.core.common.widgets.widgets.ProxyWidget` with a radio already checked
proxy_widget = ProxyWidget()
proxy_widget.no_proxy_radio.setChecked(True)
# WHEN: 'Checking' the `manual_proxy_radio` button
proxy_widget.manual_proxy_radio.setChecked(True)
# THEN: The other radio buttons should not be checked and the line edits should be enabled
assert proxy_widget.no_proxy_radio.isChecked() is False
assert proxy_widget.use_sysem_proxy_radio.isChecked() is False
assert proxy_widget.http_edit.isEnabled() is True
assert proxy_widget.https_edit.isEnabled() is True
assert proxy_widget.username_edit.isEnabled() is True
assert proxy_widget.password_edit.isEnabled() is True
def test_proxy_widget_load_default_settings(settings):
"""
Test that the default settings are loaded from the config correctly
"""
# GIVEN: And instance of the widget with default settings
proxy_widget = ProxyWidget()
# WHEN: Calling the `load` method
proxy_widget.load()
# THEN: The widget should be in its default state
assert proxy_widget.use_sysem_proxy_radio.isChecked() is True
assert proxy_widget.http_edit.text() == ''
assert proxy_widget.https_edit.text() == ''
assert proxy_widget.username_edit.text() == ''
assert proxy_widget.password_edit.text() == ''
@patch.object(ProxyWidget, 'load')
def test_proxy_widget_save_no_proxy_settings(proxy_widget_load_patcher, qapp, mock_settings):
"""
Test that the settings are saved correctly
"""
# GIVEN: A Mocked settings instance of the proxy widget with some known values set
proxy_widget = ProxyWidget()
proxy_widget.no_proxy_radio.setChecked(True)
proxy_widget.http_edit.setText('')
proxy_widget.https_edit.setText('')
proxy_widget.username_edit.setText('')
proxy_widget.password_edit.setText('')
# WHEN: Calling save
proxy_widget.save()
# THEN: The settings should be set as expected
mock_settings.setValue.assert_has_calls(
[call('advanced/proxy mode', ProxyMode.NO_PROXY),
call('advanced/proxy http', ''),
call('advanced/proxy https', ''),
call('advanced/proxy username', ''),
call('advanced/proxy password', '')])
@patch.object(ProxyWidget, 'load')
def test_proxy_widget_save_manual_settings(proxy_widget_load_patcher, qapp, mock_settings):
"""
Test that the settings are saved correctly
"""
# GIVEN: A Mocked and instance of the proxy widget with some known values set
proxy_widget = ProxyWidget()
proxy_widget.manual_proxy_radio.setChecked(True)
proxy_widget.http_edit.setText('http_proxy_server:port')
proxy_widget.https_edit.setText('https_proxy_server:port')
proxy_widget.username_edit.setText('username')
proxy_widget.password_edit.setText('password')
# WHEN: Calling save
proxy_widget.save()
# THEN: The settings should be set as expected
mock_settings.setValue.assert_has_calls(
[call('advanced/proxy mode', ProxyMode.MANUAL_PROXY),
call('advanced/proxy http', 'http_proxy_server:port'),
call('advanced/proxy https', 'https_proxy_server:port'),
call('advanced/proxy username', 'username'),
call('advanced/proxy password', 'password')])
def test_proxy_dialog_init(settings):
"""Test that the ProxyDialog is created successfully"""
# GIVEN: ProxyDialog class
# WHEN: It is instantiated
# THEN: There should be no problems
ProxyDialog()
def test_proxy_dialog_accept(settings):
"""Test that the accept() method of the ProxyDialog works correctly"""
# GIVEN: An instance of a ProxyDialog with a mocked out widget
dlg = ProxyDialog()
dlg.proxy_widget = MagicMock()
# WHEN: accept() is called
dlg.accept()
# THEN: The save() method on the widget should have been called
dlg.proxy_widget.save.assert_called_once()
def test_screen_button_initialisation():
"""
Test the initialisation of the ScreenButton object
"""
# GIVEN: A mocked screen object
screen_mock = MagicMock(spec=Screen)
screen_mock.number = 0
screen_mock.geometry = None
screen_mock.__str__.return_value = 'Mocked Screen Object'
# WHEN: initialising the ScreenButton object
instance = ScreenButton(None, screen_mock)
# THEN: The ScreenButton should have been initalised correctly with the data from the mocked screen object
assert isinstance(instance, QtWidgets.QPushButton)
assert instance.objectName() == 'screen_0_button'
assert instance.isCheckable() is True
assert instance.text() == 'Mocked Screen Object'
def test_init_default_args():
"""
Test the initialisation of ScreenSelectionWidget, when initialised with default arguments
"""
# GIVEN: The ScreenSelectionWidget class
# WHEN: Initialising ScreenSelectionWidget with default arguments
with patch('openlp.core.widgets.widgets.QtCore.QTimer') as MockTimer:
mocked_timer = MagicMock()
MockTimer.return_value = mocked_timer
instance = ScreenSelectionWidget()
# THEN: ScreenSelectionWidget should be an instance of QWidget and the screens attribute should be an empty list
assert isinstance(instance, QtWidgets.QWidget)
assert instance.screens == []
mocked_timer.setSingleShot.assert_called_once_with(True)
mocked_timer.setInterval.assert_called_once_with(3000)
def test_init_with_args():
"""
Test the initialisation of ScreenSelectionWidget, when initialised with the screens keyword arg set
"""
# GIVEN: The ScreenSelectionWidget class
screens_object_mock = MagicMock()
# WHEN: Initialising ScreenSelectionWidget with the screens keyword arg set
with patch('openlp.core.widgets.widgets.QtCore.QTimer') as MockTimer:
mocked_timer = MagicMock()
MockTimer.return_value = mocked_timer
instance = ScreenSelectionWidget(screens=screens_object_mock)
# THEN: ScreenSelectionWidget should be an instance of QWidget and the screens attribute should the mock used
assert isinstance(instance, QtWidgets.QWidget)
assert instance.screens is screens_object_mock
mocked_timer.setSingleShot.assert_called_once_with(True)
mocked_timer.setInterval.assert_called_once_with(3000)
def test_save_screen_none():
"""
Test ScreenSelectionWidget._save_screen when called with the screen arg set as None
"""
# GIVEN: An instance of the ScreenSelectionWidget
instance = ScreenSelectionWidget()
instance.display_group_box = MagicMock(spec=QtWidgets.QGroupBox)
# WHEN: Calling _save_screen and no screen is selected
instance._save_screen(None)
# THEN: _save_screen should return without attempting to write to the screen object
instance.display_group_box.isChecked.assert_not_called()
def test_save_screen_not_display():
"""
Test ScreenSelectionWidget._save_screen when the display_group_box is not checked.
"""
# GIVEN: An instance of the ScreenSelectionWidget, and a mocked group_box
instance = ScreenSelectionWidget()
instance.display_group_box = MagicMock(spec=QtWidgets.QGroupBox)
instance.custom_geometry_button = MagicMock(spec=QtWidgets.QRadioButton, **{'isChecked.return_value': False})
mocked_screen_object = MagicMock(spec=Screen)
mocked_screen_object.is_dislpay = True
# WHEN: display_group_box isn't checked and _save_screen is called with a mocked Screen object.
instance.display_group_box.isChecked.return_value = False
instance._save_screen(mocked_screen_object)
# THEN: _save_screen should should be set to False
assert mocked_screen_object.is_display is False
def test_save_screen_display():
"""
Test ScreenSelectionWidget._save_screen when the display_group_box is checked.
"""
# GIVEN: An instance of the ScreenSelectionWidget, and a mocked group_box
instance = ScreenSelectionWidget()
instance.display_group_box = MagicMock(spec=QtWidgets.QGroupBox)
instance.custom_geometry_button = MagicMock(spec=QtWidgets.QRadioButton, **{'isChecked.return_value': False})
mocked_screen_object = MagicMock(spec=Screen)
# WHEN: display_group_box is checked and _save_screen is called with a mocked Screen object.
instance.display_group_box.isChecked.return_value = True
instance._save_screen(mocked_screen_object)
# THEN: _save_screen should should be set to True
assert mocked_screen_object.is_display is True
@patch('openlp.core.widgets.widgets.QtCore.QRect')
def test_save_screen_full_screen(mocked_q_rect):
"""
Test ScreenSelectionWidget._save_screen when the display is set to full screen
"""
# GIVEN: An instance of the ScreenSelectionWidget, and a mocked custom_geometry_button
instance = ScreenSelectionWidget()
instance.display_group_box = MagicMock(spec=QtWidgets.QGroupBox)
instance.custom_geometry_button = MagicMock(spec=QtWidgets.QRadioButton)
mocked_screen_object = MagicMock(spec=Screen)
# WHEN: custom_geometry_button isn't checked and _save_screen is called with a mocked Screen object.
instance.custom_geometry_button.isChecked.return_value = False
instance._save_screen(mocked_screen_object)
# THEN: _save_screen should not attempt to save a custom geometry
mocked_q_rect.assert_not_called()
@patch('openlp.core.widgets.widgets.QtCore.QRect')
def test_save_screen_custom_geometry(mocked_q_rect):
"""
Test ScreenSelectionWidget._save_screen when a custom geometry is set
"""
# GIVEN: An instance of the ScreenSelectionWidget, and a mocked custom_geometry_button
instance = ScreenSelectionWidget()
instance.display_group_box = MagicMock(spec=QtWidgets.QGroupBox)
instance.custom_geometry_button = MagicMock(spec=QtWidgets.QRadioButton)
instance.left_spin_box = MagicMock(spec=QtWidgets.QSpinBox, **{'value.return_value': 100})
instance.top_spin_box = MagicMock(spec=QtWidgets.QSpinBox, **{'value.return_value': 200})
instance.width_spin_box = MagicMock(spec=QtWidgets.QSpinBox, **{'value.return_value': 300})
instance.height_spin_box = MagicMock(spec=QtWidgets.QSpinBox, **{'value.return_value': 400})
mocked_screen_object = MagicMock(spec=Screen)
# WHEN: custom_geometry_button is checked and _save_screen is called with a mocked Screen object.
instance.custom_geometry_button.isChecked.return_value = True
instance._save_screen(mocked_screen_object)
# THEN: _save_screen should save the custom geometry
mocked_q_rect.assert_called_once_with(100, 200, 300, 400)
def test_setup_spin_box():
"""
Test that ScreenSelectionWidget._setup_spin_box sets up the given spinbox correctly
"""
# GIVEN: An instance of the ScreenSelectionWidget class and a mocked spin box object
instance = ScreenSelectionWidget()
spin_box_mock = MagicMock(spec=QtWidgets.QSpinBox)
# WHEN: Calling _setup_spin_box with the mocked spin box object and some sample values
instance._setup_spin_box(spin_box_mock, 0, 100, 50)
# THEN: The mocked spin box object should have been set up with the specified values
spin_box_mock.setMinimum.assert_called_once_with(0)
spin_box_mock.setMaximum.assert_called_once_with(100)
spin_box_mock.setValue.assert_called_once_with(50)
def test_load():
"""
Test that ScreenSelectionWidget.load() loads the screens correctly
"""
# GIVEN: An instance of the ScreenSelectionWidget and a whole bunch o' mocks
instance = ScreenSelectionWidget()
mocked_widget = MagicMock()
mocked_item = MagicMock()
mocked_item.widget.return_value = mocked_widget
mocked_screen_frame_layout = MagicMock()
mocked_screen_frame_layout.count.side_effect = [1, 0]
mocked_screen_frame_layout.takeAt.return_value = mocked_item
mocked_screen_button_group = MagicMock()
mocked_screen_button_group.buttons.return_value = [mocked_widget]
instance.screen_frame_layout = mocked_screen_frame_layout
instance.screen_button_group = mocked_screen_button_group
instance.screens = [Screen(number=0)]
# WHEN: load() is called
with patch('openlp.core.widgets.widgets.ScreenButton'):
instance.load()
# THEN: The mocks should have been called
mocked_widget.setParent.assert_called_once_with(None)
mocked_widget.deleteLater.assert_called_once()
mocked_screen_button_group.removeButton.assert_called_once_with(mocked_widget)
def test_on_identify_timer_shot():
"""
Test that the _on_identify_timer_shot() method removes the labels from the screens
"""
# GIVEN: A ScreenSelectionWidget and a bunch o' mocks
instance = ScreenSelectionWidget()
mocked_label = MagicMock()
instance.identify_labels = [mocked_label]
# WHEN: _on_identify_timer_shot() is called
instance._on_identify_timer_shot()
# THEN: The labels should be cleared
mocked_label.hide.assert_called_once()
mocked_label.setParent.assert_called_once_with(None)
mocked_label.deleteLater.assert_called_once()
assert instance.identify_labels == []
def test_on_identify_button_clicked():
"""
Test that the on_identify_button_clicked() method shows a label on each screen
"""
# GIVEN: A ScreenSelectionWidget and a bunch o' mocks
instance = ScreenSelectionWidget()
mocked_screen = MagicMock()
mocked_screen.geometry.x.return_value = 0
mocked_screen.geometry.y.return_value = 0
mocked_screen.geometry.width.return_value = 1920
mocked_screen.__str__.return_value = 'Screen 1'
instance.screens = [mocked_screen]
instance.timer = MagicMock()
# WHEN: on_identify_button_clicked() is called
with patch('openlp.core.widgets.widgets.QtWidgets.QLabel') as MockLabel:
mocked_label = MagicMock()
MockLabel.return_value = mocked_label
instance.on_identify_button_clicked()
# THEN: The labels should be cleared
MockLabel.assert_called_once_with(None)
mocked_label.setAlignment.assert_called_once_with(QtCore.Qt.AlignCenter)
mocked_label.setText.assert_called_once_with('Screen 1')
mocked_label.setStyleSheet.assert_called_once_with('font-size: 24pt; font-weight: bold; '
'background-color: #0C0; color: #000; '
'border: 5px solid #000;')
mocked_label.setGeometry.assert_called_once_with(QtCore.QRect(0, 0, 1920, 100))
mocked_label.setWindowFlags.assert_called_once_with(QtCore.Qt.FramelessWindowHint | QtCore.Qt.Tool |
QtCore.Qt.WindowStaysOnTopHint |
QtCore.Qt.WindowDoesNotAcceptFocus)
mocked_label.show.assert_called_once()
assert instance.identify_labels == [mocked_label]
instance.timer.start.assert_called_once()
def test_on_display_clicked_with_checked():
"""
Test that the on_display_clicked() sets the first screen as display when the checkbx is checked
"""
# GIVEN: A ScreenSelectionWidget and a bunch o' mocks
instance = ScreenSelectionWidget()
mocked_screen_1 = MagicMock()
mocked_screen_2 = MagicMock()
mocked_screen_2.is_display = True
instance.screens = [mocked_screen_1, mocked_screen_2]
instance.current_screen = mocked_screen_1
# WHEN: on_display_clicked() is called when the checkbox is checked
instance.on_display_clicked(True)
# THEN: The first screen should be marked as a display
assert mocked_screen_1.is_display is True
assert mocked_screen_2.is_display is False
def test_on_display_clicked_with_unchecked():
"""
Test that the on_display_clicked() disallows the checkbox to be unchecked
"""
# GIVEN: A ScreenSelectionWidget and a bunch o' mocks
instance = ScreenSelectionWidget()
mocked_screen_1 = MagicMock()
mocked_screen_2 = MagicMock()
mocked_screen_2.is_display = True
instance.screens = [mocked_screen_1, mocked_screen_2]
instance.current_screen = mocked_screen_2
# WHEN: on_display_clicked() is called when the checkbox is checked
with patch('openlp.core.widgets.widgets.translate') as mocked_translate, \
patch('openlp.core.widgets.widgets.critical_error_message_box') as mocked_error:
mocked_translate.side_effect = lambda c, s: s
instance.on_display_clicked(False)
# THEN: The first screen should be marked as a display
mocked_error.assert_called_once_with('Select a Display',
'You need to select at least one screen to be used as a display. '
'Select the screen you wish to use as a display, and check the '
'checkbox for that screen.', parent=instance, question=False)
assert instance.use_screen_check_box.isChecked() is True
assert instance.display_group_box.isChecked() is True
def test_screen_selection_save(mock_settings):
"""
Test that the save() method saves the screens
"""
# GIVEN: A ScreenSelectionWidget and a bunch o' mocks
mocked_screen = MagicMock(**{'number': 0, 'to_dict.return_value': {'number': 0}})
instance = ScreenSelectionWidget()
instance._save_screen = MagicMock()
instance.screens = [mocked_screen]
instance.current_screen = mocked_screen
instance.save()
# THEN: The right things should happen
instance._save_screen.assert_called_once_with(mocked_screen)
mocked_screen.to_dict.assert_called_once()
mock_settings.setValue.assert_called_once_with('core/screens', {0: {'number': 0}})