Add discoverable rooms to desktop lobby

desktop-client/test_lobby_sessions.py

@@ -0,0 +1,23 @@
+from lobby_widget import LobbyWidget
+
+
+def test_session_selection_uses_existing_join_flow(qtbot):
+    lobby = LobbyWidget()
+    qtbot.addWidget(lobby)
+    assert lobby.listed_checkbox.isChecked()
+    rooms = [{"code": "ABC123", "fileInfo": {"name": "movie.mkv"},
+              "users": ["Host"], "playing": True, "position": 75}]
+    lobby.update_sessions(rooms)
+    lobby.sessions_list.setCurrentRow(0)
+    assert not lobby.session_join_btn.isEnabled()
+    lobby.username_input.setText("Alex")
+    assert lobby.session_join_btn.isEnabled()
+    with qtbot.waitSignal(lobby.join_requested) as signal:
+        lobby.join_selected_session()
+    assert signal.args == ["Alex", "ABC123"]
+    lobby.reset_ui()
+    lobby.update_sessions(rooms)
+    assert lobby.sessions_list.currentItem().data(256) == "ABC123"
+    lobby.update_sessions([])
+    assert not lobby.session_join_btn.isEnabled()
+    assert "No active sessions" in lobby.sessions_status.text()