Harden recorder shutdown with guaranteed stream close

tests/test_recorder.py

@@ -0,0 +1,80 @@
+import sys
+import unittest
+from pathlib import Path
+
+import numpy as np
+
+ROOT = Path(__file__).resolve().parents[1]
+SRC = ROOT / "src"
+if str(SRC) not in sys.path:
+    sys.path.insert(0, str(SRC))
+
+from recorder import RecordResult, stop_recording
+
+
+class _Stream:
+    def __init__(self, *, stop_exc: Exception | None = None, close_exc: Exception | None = None):
+        self.stop_exc = stop_exc
+        self.close_exc = close_exc
+        self.stop_calls = 0
+        self.close_calls = 0
+
+    def stop(self) -> None:
+        self.stop_calls += 1
+        if self.stop_exc is not None:
+            raise self.stop_exc
+
+    def close(self) -> None:
+        self.close_calls += 1
+        if self.close_exc is not None:
+            raise self.close_exc
+
+
+class RecorderTests(unittest.TestCase):
+    def test_stop_recording_closes_stream_when_stop_raises(self):
+        stream = _Stream(stop_exc=RuntimeError("stop boom"))
+        record = RecordResult()
+
+        with self.assertRaisesRegex(RuntimeError, "stop boom"):
+            stop_recording(stream, record)
+
+        self.assertEqual(stream.stop_calls, 1)
+        self.assertEqual(stream.close_calls, 1)
+
+    def test_stop_recording_raises_close_error_when_stop_succeeds(self):
+        stream = _Stream(close_exc=RuntimeError("close boom"))
+        record = RecordResult()
+
+        with self.assertRaisesRegex(RuntimeError, "close boom"):
+            stop_recording(stream, record)
+
+        self.assertEqual(stream.stop_calls, 1)
+        self.assertEqual(stream.close_calls, 1)
+
+    def test_stop_recording_raises_stop_error_when_both_fail(self):
+        stream = _Stream(
+            stop_exc=RuntimeError("stop boom"),
+            close_exc=RuntimeError("close boom"),
+        )
+        record = RecordResult()
+
+        with self.assertLogs(level="WARNING") as logs:
+            with self.assertRaisesRegex(RuntimeError, "stop boom"):
+                stop_recording(stream, record)
+
+        self.assertEqual(stream.stop_calls, 1)
+        self.assertEqual(stream.close_calls, 1)
+        self.assertTrue(
+            any("stream close failed after stop failure: close boom" in line for line in logs.output)
+        )
+
+    def test_stop_recording_with_no_stream_flattens_frames(self):
+        record = RecordResult(frames=[np.array([[0.2], [0.4]], dtype=np.float32)])
+
+        audio = stop_recording(None, record)
+
+        np.testing.assert_allclose(audio, np.array([0.2, 0.4], dtype=np.float32))
+
+
+if __name__ == "__main__":
+    unittest.main()