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path: root/tests/unit/config/test_qtargs.py
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# vim: ft=python fileencoding=utf-8 sts=4 sw=4 et:
# Copyright 2017-2021 Florian Bruhin (The Compiler) <mail@qutebrowser.org>

# This file is part of qutebrowser.
#
# qutebrowser 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.
#
# qutebrowser 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 qutebrowser.  If not, see <https://www.gnu.org/licenses/>.

import sys
import os
import logging

import pytest

from qutebrowser import qutebrowser
from qutebrowser.config import qtargs
from qutebrowser.utils import usertypes, version
from helpers import testutils


@pytest.fixture
def parser(mocker):
    """Fixture to provide an argparser.

    Monkey-patches .exit() of the argparser so it doesn't exit on errors.
    """
    parser = qutebrowser.get_argparser()
    mocker.patch.object(parser, 'exit', side_effect=Exception)
    return parser


@pytest.fixture
def version_patcher(monkeypatch):
    """Get a patching function to patch the QtWebEngine version."""
    def run(ver):
        versions = version.WebEngineVersions.from_pyqt(ver)
        monkeypatch.setattr(qtargs.objects, 'backend', usertypes.Backend.QtWebEngine)
        monkeypatch.setattr(version, 'qtwebengine_versions',
                            lambda avoid_init: versions)

    return run


@pytest.fixture
def reduce_args(config_stub, version_patcher, monkeypatch):
    """Make sure no --disable-shared-workers/referer argument get added."""
    version_patcher('5.15.3')
    config_stub.val.content.headers.referer = 'always'
    config_stub.val.scrolling.bar = 'never'
    monkeypatch.setattr(qtargs.utils, 'is_mac', False)
    # Avoid WebRTC pipewire feature
    monkeypatch.setattr(qtargs.utils, 'is_linux', False)


@pytest.mark.usefixtures('reduce_args')
class TestQtArgs:

    @pytest.mark.parametrize('args, expected', [
        # No Qt arguments
        (['--debug'], [sys.argv[0]]),
        # Qt flag
        (['--debug', '--qt-flag', 'reverse'], [sys.argv[0], '--reverse']),
        # Qt argument with value
        (['--qt-arg', 'stylesheet', 'foo'],
         [sys.argv[0], '--stylesheet', 'foo']),
        # --qt-arg given twice
        (['--qt-arg', 'stylesheet', 'foo', '--qt-arg', 'geometry', 'bar'],
         [sys.argv[0], '--stylesheet', 'foo', '--geometry', 'bar']),
        # --qt-flag given twice
        (['--qt-flag', 'foo', '--qt-flag', 'bar'],
         [sys.argv[0], '--foo', '--bar']),
    ])
    def test_qt_args(self, monkeypatch, config_stub, args, expected, parser):
        """Test commandline with no Qt arguments given."""
        parsed = parser.parse_args(args)
        assert qtargs.qt_args(parsed) == expected

    def test_qt_both(self, config_stub, parser):
        """Test commandline with a Qt argument and flag."""
        args = parser.parse_args(['--qt-arg', 'stylesheet', 'foobar',
                                  '--qt-flag', 'reverse'])
        qt_args = qtargs.qt_args(args)
        assert qt_args[0] == sys.argv[0]
        assert '--reverse' in qt_args
        assert '--stylesheet' in qt_args
        assert 'foobar' in qt_args

    def test_with_settings(self, config_stub, parser):
        parsed = parser.parse_args(['--qt-flag', 'foo'])
        config_stub.val.qt.args = ['bar']
        args = qtargs.qt_args(parsed)
        assert args[0] == sys.argv[0]
        for arg in ['--foo', '--bar']:
            assert arg in args


def test_no_webengine_available(monkeypatch, config_stub, parser, stubs):
    """Test that we don't fail if QtWebEngine is requested but unavailable.

    Note this is not inside TestQtArgs because we don't want the reduce_args patching
    here.
    """
    monkeypatch.setattr(qtargs.objects, 'backend', usertypes.Backend.QtWebEngine)

    fake = stubs.ImportFake({'qutebrowser.browser.webengine': False}, monkeypatch)
    fake.patch()

    parsed = parser.parse_args([])
    args = qtargs.qt_args(parsed)
    assert args == [sys.argv[0]]


@pytest.mark.usefixtures('reduce_args')
class TestWebEngineArgs:

    @pytest.fixture(autouse=True)
    def ensure_webengine(self, monkeypatch):
        """Skip all tests if QtWebEngine is unavailable."""
        pytest.importorskip("PyQt5.QtWebEngine")
        monkeypatch.setattr(qtargs.objects, 'backend', usertypes.Backend.QtWebEngine)

    @pytest.mark.parametrize('backend, qt_version, expected', [
        (usertypes.Backend.QtWebEngine, '5.13.0', False),
        (usertypes.Backend.QtWebEngine, '5.14.0', True),
        (usertypes.Backend.QtWebEngine, '5.14.1', True),
        (usertypes.Backend.QtWebEngine, '5.15.0', False),
        (usertypes.Backend.QtWebEngine, '5.15.1', False),

        (usertypes.Backend.QtWebKit, '5.14.0', False),
    ])
    def test_shared_workers(self, config_stub, version_patcher, monkeypatch, parser,
                            qt_version, backend, expected):
        version_patcher(qt_version)
        monkeypatch.setattr(qtargs.objects, 'backend', backend)
        parsed = parser.parse_args([])
        args = qtargs.qt_args(parsed)
        assert ('--disable-shared-workers' in args) == expected

    @pytest.mark.parametrize('backend, qt_version, debug_flag, expected', [
        # Qt >= 5.12.3: Enable with -D stack, do nothing without it.
        (usertypes.Backend.QtWebEngine, '5.12.3', True, True),
        (usertypes.Backend.QtWebEngine, '5.12.3', False, None),
        # Qt < 5.12.3: Do nothing with -D stack, disable without it.
        (usertypes.Backend.QtWebEngine, '5.12.2', True, None),
        (usertypes.Backend.QtWebEngine, '5.12.2', False, False),
        # QtWebKit: Do nothing
        (usertypes.Backend.QtWebKit, '5.12.3', True, None),
        (usertypes.Backend.QtWebKit, '5.12.3', False, None),
        (usertypes.Backend.QtWebKit, '5.12.2', True, None),
        (usertypes.Backend.QtWebKit, '5.12.2', False, None),
    ])
    def test_in_process_stack_traces(self, monkeypatch, parser, backend, version_patcher,
                                     qt_version, debug_flag, expected):
        version_patcher(qt_version)
        monkeypatch.setattr(qtargs.objects, 'backend', backend)
        parsed = parser.parse_args(['--debug-flag', 'stack'] if debug_flag
                                   else [])
        args = qtargs.qt_args(parsed)

        if expected is None:
            assert '--disable-in-process-stack-traces' not in args
            assert '--enable-in-process-stack-traces' not in args
        elif expected:
            assert '--disable-in-process-stack-traces' not in args
            assert '--enable-in-process-stack-traces' in args
        else:
            assert '--disable-in-process-stack-traces' in args
            assert '--enable-in-process-stack-traces' not in args

    @pytest.mark.parametrize('flags, args', [
        ([], []),
        (['--debug-flag', 'chromium'], ['--enable-logging', '--v=1']),
        (['--debug-flag', 'wait-renderer-process'], ['--renderer-startup-dialog']),
    ])
    def test_chromium_flags(self, monkeypatch, parser, flags, args):
        parsed = parser.parse_args(flags)
        args = qtargs.qt_args(parsed)

        if args:
            for arg in args:
                assert arg in args
        else:
            assert '--enable-logging' not in args
            assert '--v=1' not in args
            assert '--renderer-startup-dialog' not in args

    @pytest.mark.parametrize('config, added', [
        ('none', False),
        ('qt-quick', False),
        ('software-opengl', False),
        ('chromium', True),
    ])
    def test_disable_gpu(self, config, added, config_stub, monkeypatch, parser):
        config_stub.val.qt.force_software_rendering = config
        parsed = parser.parse_args([])
        args = qtargs.qt_args(parsed)
        assert ('--disable-gpu' in args) == added

    @pytest.mark.parametrize('policy, arg', [
        ('all-interfaces', None),

        ('default-public-and-private-interfaces',
         '--force-webrtc-ip-handling-policy='
         'default_public_and_private_interfaces'),

        ('default-public-interface-only',
         '--force-webrtc-ip-handling-policy='
         'default_public_interface_only'),

        ('disable-non-proxied-udp',
         '--force-webrtc-ip-handling-policy='
         'disable_non_proxied_udp'),
    ])
    def test_webrtc(self, config_stub, monkeypatch, parser, policy, arg):
        config_stub.val.content.webrtc_ip_handling_policy = policy

        parsed = parser.parse_args([])
        args = qtargs.qt_args(parsed)

        if arg is None:
            assert not any(a.startswith('--force-webrtc-ip-handling-policy=')
                           for a in args)
        else:
            assert arg in args

    @pytest.mark.parametrize('canvas_reading, added', [
        (True, False),  # canvas reading enabled
        (False, True),
    ])
    def test_canvas_reading(self, config_stub, parser, canvas_reading, added):
        config_stub.val.content.canvas_reading = canvas_reading
        parsed = parser.parse_args([])
        args = qtargs.qt_args(parsed)
        assert ('--disable-reading-from-canvas' in args) == added

    @pytest.mark.parametrize('process_model, added', [
        ('process-per-site-instance', False),
        ('process-per-site', True),
        ('single-process', True),
    ])
    def test_process_model(self, config_stub, parser, process_model, added):
        config_stub.val.qt.process_model = process_model
        parsed = parser.parse_args([])
        args = qtargs.qt_args(parsed)

        if added:
            assert '--' + process_model in args
        else:
            assert '--process-per-site' not in args
            assert '--single-process' not in args
            assert '--process-per-site-instance' not in args
            assert '--process-per-tab' not in args

    @pytest.mark.parametrize('low_end_device_mode, arg', [
        ('auto', None),
        ('always', '--enable-low-end-device-mode'),
        ('never', '--disable-low-end-device-mode'),
    ])
    def test_low_end_device_mode(self, config_stub, parser, low_end_device_mode, arg):
        config_stub.val.qt.low_end_device_mode = low_end_device_mode
        parsed = parser.parse_args([])
        args = qtargs.qt_args(parsed)

        if arg is None:
            assert '--enable-low-end-device-mode' not in args
            assert '--disable-low-end-device-mode' not in args
        else:
            assert arg in args

    @pytest.mark.parametrize('qt_version, referer, arg', [
        # 'always' -> no arguments
        ('5.15.0', 'always', None),

        # 'never' is handled via interceptor for most Qt versions
        ('5.12.3', 'never', '--no-referrers'),
        ('5.12.4', 'never', None),
        ('5.13.0', 'never', '--no-referrers'),
        ('5.13.1', 'never', None),
        ('5.14.0', 'never', None),
        ('5.15.0', 'never', None),

        # 'same-domain' - arguments depend on Qt versions
        ('5.13.0', 'same-domain', '--reduced-referrer-granularity'),
        ('5.14.0', 'same-domain', '--enable-features=ReducedReferrerGranularity'),
        ('5.15.0', 'same-domain', '--enable-features=ReducedReferrerGranularity'),
    ])
    def test_referer(self, config_stub, version_patcher, parser,
                     qt_version, referer, arg):
        version_patcher(qt_version)

        config_stub.val.content.headers.referer = referer
        parsed = parser.parse_args([])
        args = qtargs.qt_args(parsed)

        if arg is None:
            assert '--no-referrers' not in args
            assert '--reduced-referrer-granularity' not in args
            assert '--enable-features=ReducedReferrerGranularity' not in args
        else:
            assert arg in args

    @pytest.mark.parametrize('value, qt_version, added', [
        ("dark", "5.13", False),  # not supported
        ("dark", "5.14", True),
        ("dark", "5.15.0", True),
        ("dark", "5.15.1", True),
        # handled via blink setting
        ("dark", "5.15.2", False),
        ("dark", "5.15.3", False),
        ("dark", "6.0.0", False),

        ("light", "5.13", False),
        ("light", "5.14", False),
        ("light", "5.15.0", False),
        ("light", "5.15.1", False),
        ("light", "5.15.2", False),
        ("light", "5.15.2", False),
        ("light", "5.15.3", False),
        ("light", "6.0.0", False),

        ("auto", "5.13", False),
        ("auto", "5.14", False),
        ("auto", "5.15.0", False),
        ("auto", "5.15.1", False),
        ("auto", "5.15.2", False),
        ("auto", "5.15.2", False),
        ("auto", "5.15.3", False),
        ("auto", "6.0.0", False),
    ])
    @testutils.qt514
    def test_preferred_color_scheme(
            self, config_stub, version_patcher, parser, value, qt_version, added):
        version_patcher(qt_version)

        config_stub.val.colors.webpage.preferred_color_scheme = value

        parsed = parser.parse_args([])
        args = qtargs.qt_args(parsed)

        assert ('--force-dark-mode' in args) == added

    @pytest.mark.parametrize('bar, is_mac, added', [
        # Overlay bar enabled
        ('overlay', False, True),
        # No overlay on mac
        ('overlay', True, False),
        # Overlay disabled
        ('when-searching', False, False),
        ('always', False, False),
        ('never', False, False),
    ])
    def test_overlay_scrollbar(self, config_stub, monkeypatch, parser,
                               bar, is_mac, added):
        monkeypatch.setattr(qtargs.utils, 'is_mac', is_mac)

        config_stub.val.scrolling.bar = bar

        parsed = parser.parse_args([])
        args = qtargs.qt_args(parsed)

        assert ('--enable-features=OverlayScrollbar' in args) == added

    @pytest.mark.parametrize('via_commandline', [True, False])
    @pytest.mark.parametrize('overlay, passed_features, expected_features', [
        (True,
         'CustomFeature',
         'CustomFeature,OverlayScrollbar'),
        (True,
         'CustomFeature1,CustomFeature2',
         'CustomFeature1,CustomFeature2,OverlayScrollbar'),
        (False,
         'CustomFeature',
         'CustomFeature'),
    ])
    def test_overlay_features_flag(self, config_stub, parser,
                                   via_commandline, overlay, passed_features,
                                   expected_features):
        """If enable-features is already specified, we should combine both."""
        config_flag = qtargs._ENABLE_FEATURES.lstrip('-') + passed_features

        config_stub.val.scrolling.bar = 'overlay' if overlay else 'never'
        config_stub.val.qt.args = ([] if via_commandline else [config_flag])

        parsed = parser.parse_args(['--qt-flag', config_flag]
                                   if via_commandline else [])
        args = qtargs.qt_args(parsed)

        overlay_flag = qtargs._ENABLE_FEATURES + 'OverlayScrollbar'
        combined_flag = qtargs._ENABLE_FEATURES + expected_features

        enable_features_args = [
            arg for arg in args
            if arg.startswith(qtargs._ENABLE_FEATURES)
        ]
        assert len(enable_features_args) == 1
        assert combined_flag in args
        assert overlay_flag not in args

    @pytest.mark.parametrize('via_commandline', [True, False])
    @pytest.mark.parametrize('passed_features', [
        ['CustomFeature'],
        ['CustomFeature1', 'CustomFeature2'],
    ])
    def test_disable_features_passthrough(self, config_stub, parser,
                                          via_commandline, passed_features):
        flag = qtargs._DISABLE_FEATURES + ','.join(passed_features)

        config_flag = flag.lstrip('-')
        config_stub.val.qt.args = ([] if via_commandline else [config_flag])
        parsed = parser.parse_args(['--qt-flag', config_flag]
                                   if via_commandline else [])
        args = qtargs.qt_args(parsed)

        disable_features_args = [
            arg for arg in args
            if arg.startswith(qtargs._DISABLE_FEATURES)
        ]
        assert disable_features_args == [flag]

    def test_blink_settings_passthrough(self, parser, config_stub):
        config_stub.val.colors.webpage.darkmode.enabled = True

        flag = qtargs._BLINK_SETTINGS + 'foo=bar'
        parsed = parser.parse_args(['--qt-flag', flag.lstrip('-')])
        args = qtargs.qt_args(parsed)

        blink_settings_args = [
            arg for arg in args
            if arg.startswith(qtargs._BLINK_SETTINGS)
        ]
        assert len(blink_settings_args) == 1
        assert blink_settings_args[0].startswith('--blink-settings=foo=bar,')

    @pytest.mark.parametrize('qt_version, has_workaround', [
        ('5.14.0', False),
        ('5.15.1', False),
        ('5.15.2', True),
        ('5.15.3', False),
        ('6.0.0', False),
    ])
    def test_installedapp_workaround(self, parser, version_patcher, qt_version, has_workaround):
        version_patcher(qt_version)

        parsed = parser.parse_args([])
        args = qtargs.qt_args(parsed)
        disable_features_args = [
            arg for arg in args
            if arg.startswith(qtargs._DISABLE_FEATURES)
        ]

        expected = ['--disable-features=InstalledApp'] if has_workaround else []
        assert disable_features_args == expected

    @pytest.mark.parametrize('enabled', [True, False])
    @testutils.qt514
    def test_media_keys(self, config_stub, parser, enabled):
        config_stub.val.input.media_keys = enabled

        parsed = parser.parse_args([])
        args = qtargs.qt_args(parsed)

        assert ('--disable-features=HardwareMediaKeyHandling' in args) != enabled

    @pytest.mark.parametrize('variant, expected', [
        (
            'qt_515_1',
            ['--blink-settings=darkModeEnabled=true,darkModeImagePolicy=2'],
        ),
        (
            'qt_515_2',
            [
                (
                    '--blink-settings=preferredColorScheme=2,'
                    'forceDarkModeEnabled=true,'
                    'forceDarkModeImagePolicy=2'
                )
            ],
        ),
        (
            'qt_515_3',
            [
                '--blink-settings=forceDarkModeEnabled=true',
                '--dark-mode-settings=ImagePolicy=2',
            ]
        ),
    ])
    def test_dark_mode_settings(self, config_stub, monkeypatch, parser,
                                variant, expected):
        from qutebrowser.browser.webengine import darkmode
        monkeypatch.setattr(
            darkmode, '_variant', lambda _versions: darkmode.Variant[variant])

        config_stub.val.colors.webpage.darkmode.enabled = True

        parsed = parser.parse_args([])
        args = qtargs.qt_args(parsed)

        for arg in expected:
            assert arg in args

    @pytest.mark.linux
    def test_locale_workaround(self, config_stub, monkeypatch, version_patcher, parser):
        class FakeLocale:

            def bcp47Name(self):
                return 'de-CH'

        monkeypatch.setattr(qtargs.utils, 'is_linux', True)  # patched in reduce_args
        monkeypatch.setattr(qtargs, 'QLocale', FakeLocale)
        version_patcher('5.15.3')

        config_stub.val.qt.workarounds.locale = True
        parsed = parser.parse_args([])
        args = qtargs.qt_args(parsed)
        assert '--lang=de' in args


class TestEnvVars:

    @pytest.mark.parametrize('config_opt, config_val, envvar, expected', [
        ('qt.force_software_rendering', 'software-opengl',
         'QT_XCB_FORCE_SOFTWARE_OPENGL', '1'),
        ('qt.force_software_rendering', 'qt-quick',
         'QT_QUICK_BACKEND', 'software'),
        ('qt.force_software_rendering', 'chromium',
         'QT_WEBENGINE_DISABLE_NOUVEAU_WORKAROUND', '1'),
        ('qt.force_platform', 'toaster', 'QT_QPA_PLATFORM', 'toaster'),
        ('qt.force_platformtheme', 'lxde', 'QT_QPA_PLATFORMTHEME', 'lxde'),
        ('window.hide_decoration', True,
         'QT_WAYLAND_DISABLE_WINDOWDECORATION', '1')
    ])
    def test_env_vars(self, monkeypatch, config_stub,
                      config_opt, config_val, envvar, expected):
        """Check settings which set an environment variable."""
        monkeypatch.setattr(qtargs.objects, 'backend',
                            usertypes.Backend.QtWebEngine)
        monkeypatch.setenv(envvar, '')  # to make sure it gets restored
        monkeypatch.delenv(envvar)

        config_stub.set_obj(config_opt, config_val)
        qtargs.init_envvars()

        assert os.environ[envvar] == expected

    @pytest.mark.parametrize('init_val, config_val', [
        (   # Test changing a set variable
            {'QT_SCALE_FACTOR': '2'},
            {'QT_SCALE_FACTOR': '4'},
        ),
        (   # Test setting an unset variable
            {'QT_SCALE_FACTOR': None},
            {'QT_SCALE_FACTOR': '3'},
        ),
        (   # Test unsetting a variable which is set
            {'QT_SCALE_FACTOR': '3'},
            {'QT_SCALE_FACTOR': None},
        ),
        (   # Test unsetting a variable which is unset
            {'QT_SCALE_FACTOR': None},
            {'QT_SCALE_FACTOR': None},
        ),
        (   # Test setting multiple variables
            {'QT_SCALE_FACTOR': '0', 'QT_PLUGIN_PATH': '/usr/bin', 'QT_NEWVAR': None},
            {'QT_SCALE_FACTOR': '3', 'QT_PLUGIN_PATH': '/tmp/', 'QT_NEWVAR': 'newval'},
        )
    ])
    def test_environ_settings(self, monkeypatch, config_stub,
                              init_val, config_val):
        """Test setting environment variables using qt.environ."""
        for var, val in init_val.items():
            if val is None:
                monkeypatch.setenv(var, '0')
                monkeypatch.delenv(var, raising=False)
            else:
                monkeypatch.setenv(var, val)

        config_stub.val.qt.environ = config_val
        qtargs.init_envvars()

        for var, result in config_val.items():
            if result is None:
                assert var not in os.environ
            else:
                assert os.environ[var] == result

    @pytest.mark.parametrize('new_qt', [True, False])
    def test_highdpi(self, monkeypatch, config_stub, new_qt):
        """Test HighDPI environment variables.

        Depending on the Qt version, there's a different variable which should
        be set...
        """
        new_var = 'QT_ENABLE_HIGHDPI_SCALING'
        old_var = 'QT_AUTO_SCREEN_SCALE_FACTOR'

        monkeypatch.setattr(qtargs.objects, 'backend',
                            usertypes.Backend.QtWebEngine)
        monkeypatch.setattr(qtargs.qtutils, 'version_check',
                            lambda version, exact=False, compiled=True:
                            new_qt)

        for envvar in [new_var, old_var]:
            monkeypatch.setenv(envvar, '')  # to make sure it gets restored
            monkeypatch.delenv(envvar)

        config_stub.set_obj('qt.highdpi', True)
        qtargs.init_envvars()

        envvar = new_var if new_qt else old_var

        assert os.environ[envvar] == '1'

    def test_env_vars_webkit(self, monkeypatch, config_stub):
        monkeypatch.setattr(qtargs.objects, 'backend',
                            usertypes.Backend.QtWebKit)
        qtargs.init_envvars()

    @pytest.mark.parametrize('backend, value, expected', [
        (usertypes.Backend.QtWebKit, None, None),
        (usertypes.Backend.QtWebKit, '--test', None),

        (usertypes.Backend.QtWebEngine, None, None),
        (usertypes.Backend.QtWebEngine, '', "''"),
        (usertypes.Backend.QtWebEngine, '--xyz', "'--xyz'"),
    ])
    def test_qtwe_flags_warning(self, monkeypatch, config_stub, caplog,
                                backend, value, expected):
        monkeypatch.setattr(qtargs.objects, 'backend', backend)
        if value is None:
            monkeypatch.delenv('QTWEBENGINE_CHROMIUM_FLAGS', raising=False)
        else:
            monkeypatch.setenv('QTWEBENGINE_CHROMIUM_FLAGS', value)

        with caplog.at_level(logging.WARNING):
            qtargs.init_envvars()

        if expected is None:
            assert not caplog.messages
        else:
            assert len(caplog.messages) == 1
            msg = caplog.messages[0]
            assert msg.startswith(f'You have QTWEBENGINE_CHROMIUM_FLAGS={expected} set')