Add test

tests/test_runserver_watch.py

@@ -1,7 +1,8 @@
 import asyncio
+import time
 from functools import partial
 from typing import Set, Tuple
-from unittest.mock import MagicMock, call
+from unittest.mock import AsyncMock, MagicMock, call
 
 from aiohttp import ClientSession
 from aiohttp.web import Application, WebSocketResponse
@@ -193,3 +194,34 @@ async def test_stop_process_dirty(mocker):
     await app_task._stop_dev_server()
     assert mock_kill.call_args_list == [call(321, 2)]
     assert process_mock.kill.called_once()
+
+
+async def test_restart_after_connection_loss(mocker):
+    mocked_awatch = mocker.patch("aiohttp_devtools.runserver.watch.awatch", autospec=True, spec_set=True)
+    mocked_awatch.side_effect = create_awatch_mock({("x", "/path/to/file.py")})
+    app_task = AppTask(MagicMock())
+    start_mock = mocker.patch.object(app_task, "_start_dev_server", autospec=True, spec_set=True)
+    mock_reload = mocker.patch.object(app_task, "_src_reload_when_live", autospec=True, spec_set=True)
+    mocker.patch.object(app_task, "_stop_dev_server", autospec=True, spec_set=True)
+
+    app = mocker.create_autospec(Application, spec_set=True, instance=True)
+    # Simulate connection lost from recent restart.
+    d = {WS: set(), LAST_RELOAD: [1, time.time()]}
+    app.__getitem__.side_effect = lambda k: d.get(k, MagicMock())
+
+    def update_ws(i):
+        d[WS].add(MagicMock(spec_set=()))
+        return AsyncMock()
+
+    sleep_mock = mocker.patch("asyncio.sleep", autospec=True, spec_set=True)
+    sleep_mock.side_effect = update_ws
+
+    await app_task.start(app)
+    assert app_task._task is not None
+    await app_task._task
+    assert sleep_mock.call_count < 5
+    assert call(0.1) in sleep_mock.call_args_list
+    mock_reload.assert_called_once()
+    assert start_mock.call_count == 2
+    assert app_task._session is not None
+    await app_task._session.close()