The desktop_notifications tests called the real init/alert/show, which
reach the libnotify daemon — every test run popped real GNOME
notifications titled "MockDevice" and "unknown".
Add an autouse conftest fixture that swaps Notify for a mock in both
desktop_notifications modules (solaar.ui and logitech_receiver). The
tests still exercise the real init/alert/show code paths, but
Notification.show() never reaches the daemon. The fixture returns the
mock; the notification tests now assert show() was actually dispatched
against it, so they verify the path instead of just "didn't crash".
Tests build FakeDevices named "TestDevice". Any test that touches
device.settings or device.persister without mocking
configuration.persister (e.g. test_device_complex, test_device_battery)
calls the real configuration.persister(), which loads and rewrites
~/.config/solaar/config.yaml — the TestDevice has no stable identity
so it never matches an existing entry, and a fresh blank TestDevice
entry is appended on every test run.
Add an autouse conftest fixture that points configuration's yaml/json
paths at a per-test tmp_path and clears the cached _config. No test
can reach the real config now, and each test starts from an empty
config instead of inheriting entries from earlier tests.
Ken Sanislo