feat: MACP Phase 2A — Event Bridge + Notification System (#11)

tests/test_event_watcher.py

@@ -0,0 +1,99 @@
+from __future__ import annotations
+
+import json
+import unittest
+
+from tests.conftest import append_ndjson, make_temp_paths, sample_events, write_ndjson
+from event_watcher import EventWatcher
+
+
+class EventWatcherTests(unittest.TestCase):
+    def setUp(self) -> None:
+        self.tempdir, self.paths = make_temp_paths()
+        self.events = sample_events()
+
+    def tearDown(self) -> None:
+        self.tempdir.cleanup()
+
+    def watcher(self) -> EventWatcher:
+        return EventWatcher(self.paths.events_path, self.paths.cursor_path, poll_interval=0.1)
+
+    def test_poll_empty_file(self) -> None:
+        watcher = self.watcher()
+        self.assertEqual(watcher.poll_once(), [])
+        self.assertFalse(self.paths.cursor_path.exists())
+
+    def test_poll_new_events(self) -> None:
+        write_ndjson(self.paths.events_path, self.events[:3])
+
+        polled = self.watcher().poll_once()
+
+        self.assertEqual(polled, self.events[:3])
+
+    def test_cursor_persistence(self) -> None:
+        watcher = self.watcher()
+        write_ndjson(self.paths.events_path, self.events[:3])
+
+        first = watcher.poll_once()
+        second = watcher.poll_once()
+
+        self.assertEqual(first, self.events[:3])
+        self.assertEqual(second, [])
+        cursor = json.loads(self.paths.cursor_path.read_text(encoding="utf-8"))
+        self.assertGreater(cursor["position"], 0)
+
+    def test_cursor_survives_restart(self) -> None:
+        write_ndjson(self.paths.events_path, self.events[:3])
+
+        first_watcher = self.watcher()
+        self.assertEqual(first_watcher.poll_once(), self.events[:3])
+
+        second_watcher = self.watcher()
+        self.assertEqual(second_watcher.poll_once(), [])
+
+    def test_corrupt_line_skipped(self) -> None:
+        self.paths.events_path.parent.mkdir(parents=True, exist_ok=True)
+        with self.paths.events_path.open("w", encoding="utf-8") as handle:
+            handle.write(json.dumps(self.events[0]) + "\n")
+            handle.write("{not-json}\n")
+            handle.write(json.dumps(self.events[1]) + "\n")
+
+        polled = self.watcher().poll_once()
+
+        self.assertEqual(polled, [self.events[0], self.events[1]])
+
+    def test_callback_filtering(self) -> None:
+        write_ndjson(self.paths.events_path, self.events)
+        received: list[dict[str, object]] = []
+        watcher = self.watcher()
+        watcher.on(["task.completed"], received.append)
+
+        watcher.poll_once()
+
+        self.assertEqual(received, [self.events[2]])
+
+    def test_callback_receives_events(self) -> None:
+        write_ndjson(self.paths.events_path, self.events[:2])
+        received: list[dict[str, object]] = []
+        watcher = self.watcher()
+        watcher.on([], received.append)
+
+        polled = watcher.poll_once()
+
+        self.assertEqual(received, self.events[:2])
+        self.assertEqual(polled, self.events[:2])
+
+    def test_file_grows_between_polls(self) -> None:
+        watcher = self.watcher()
+        write_ndjson(self.paths.events_path, self.events[:2])
+
+        first = watcher.poll_once()
+        append_ndjson(self.paths.events_path, self.events[2:5])
+        second = watcher.poll_once()
+
+        self.assertEqual(first, self.events[:2])
+        self.assertEqual(second, self.events[2:5])
+
+
+if __name__ == "__main__":
+    unittest.main()