Cancel Borg thread at end of test. (#648)

Maybe fixes #632

tests/conftest.py

@@ -52,6 +52,17 @@ def local_en():
     os.environ['LANG'] = 'en'
 
 
+@pytest.fixture(scope='function', autouse=True)
+def cleanup(request, qapp, qtbot):
+    """
+    Ensure BorgThread is stopped when new test starts.
+    """
+    def ensure_borg_thread_stopped():
+        qapp.backup_cancelled_event.emit()
+        qtbot.waitUntil(lambda: not vorta.borg.borg_thread.BorgThread.is_running())
+    request.addfinalizer(ensure_borg_thread_stopped)
+
+
 @pytest.fixture(scope='session')
 def qapp(tmpdir_factory, local_en):
     tmp_db = tmpdir_factory.mktemp('Vorta').join('settings.sqlite')