added capture time for every sweep

python_app/tests/test_shm_ipc.py

@@ -39,12 +39,19 @@ from python_app.orchestration.shm.ring_writer import ShmRingWriter
 from python_app.storage.npz.serialize import serialize_result_collection, serialize_trace_collection
 
 
-def _trace(in_pos: int, out_pos: int, n: int) -> TraceData:
+def _trace(in_pos: int, out_pos: int, n: int, *, capture_ns: tuple[int, int] = (0, 0)) -> TraceData:
     """Build a trace with float32-exact data so round-trips compare exactly."""
     freq = np.arange(n, dtype=np.float32) + 1.0
     s11 = (np.arange(n, dtype=np.float32) + 0.5j * np.arange(n, dtype=np.float32)).astype(np.complex64)
     s21 = (-np.arange(n, dtype=np.float32) + 2.0j * np.arange(n, dtype=np.float32)).astype(np.complex64)
-    return TraceData(combo=ComboKey(input=in_pos, output=out_pos), frequency_hz=freq, s11=s11, s21=s21)
+    return TraceData(
+        combo=ComboKey(input=in_pos, output=out_pos),
+        frequency_hz=freq,
+        s11=s11,
+        s21=s21,
+        capture_start_ns=capture_ns[0],
+        capture_end_ns=capture_ns[1],
+    )
 
 
 class TraceCollectionRoundTripTest(unittest.TestCase):
@@ -52,7 +59,7 @@ class TraceCollectionRoundTripTest(unittest.TestCase):
         collection = SweepCollection(
             collection_id=7,
             monotonic_ns=123,
-            traces=[_trace(0, 0, 4), _trace(3, 1, 2)],
+            traces=[_trace(0, 0, 4, capture_ns=(11, 13)), _trace(3, 1, 2, capture_ns=(15, 19))],
             capture_start_ns=10,
             capture_end_ns=20,
         )
@@ -66,6 +73,10 @@ class TraceCollectionRoundTripTest(unittest.TestCase):
             self.assertTrue(np.array_equal(got.frequency_hz, original.frequency_hz))
             self.assertTrue(np.array_equal(got.s11, original.s11))
             self.assertTrue(np.array_equal(got.s21, original.s21))
+            self.assertEqual(
+                (got.capture_start_ns, got.capture_end_ns),
+                (original.capture_start_ns, original.capture_end_ns),
+            )
 
     def test_raw_round_trips(self) -> None:
         self._assert_round_trips(RAW_MAGIC)
@@ -78,6 +89,34 @@ class TraceCollectionRoundTripTest(unittest.TestCase):
         decoded = decode_trace_collection(serialize_trace_collection(collection, RAW_MAGIC), RAW_MAGIC)
         self.assertEqual(decoded.traces, [])
 
+    def test_payload_without_per_trace_window_table_still_decodes(self) -> None:
+        # A producer built before per-trace timing stops after the collection
+        # window; its traces must still decode, with the timestamps left at zero.
+        collection = SweepCollection(
+            collection_id=4,
+            monotonic_ns=5,
+            traces=[_trace(1, 0, 3, capture_ns=(7, 9))],
+            capture_start_ns=6,
+            capture_end_ns=10,
+        )
+        full = serialize_trace_collection(collection, RAW_MAGIC)
+        legacy = full[: -(4 + 16 * len(collection.traces))]
+
+        decoded = decode_trace_collection(legacy, RAW_MAGIC)
+        self.assertEqual((decoded.capture_start_ns, decoded.capture_end_ns), (6, 10))
+        self.assertEqual(len(decoded.traces), 1)
+        self.assertEqual((decoded.traces[0].capture_start_ns, decoded.traces[0].capture_end_ns), (0, 0))
+
+    def test_per_trace_window_count_mismatch_is_rejected(self) -> None:
+        collection = SweepCollection(
+            collection_id=4, monotonic_ns=5, traces=[_trace(1, 0, 3, capture_ns=(7, 9))]
+        )
+        payload = serialize_trace_collection(collection, RAW_MAGIC)
+        # Overwrite the window-table count (u32 before the single 16-byte pair).
+        corrupt = payload[:-20] + struct.pack("<I", 2) + payload[-16:]
+        with self.assertRaises(ValueError):
+            decode_trace_collection(corrupt, RAW_MAGIC)
+
 
 class ResultCollectionRoundTripTest(unittest.TestCase):
     def test_all_payload_kinds_round_trip(self) -> None:

python_app/tests/test_switched_matrix_capture.py

@@ -140,6 +140,36 @@ class SwitchedMatrixComboAcquisitionTest(unittest.TestCase):
             expected_combos,
         )
 
+    def test_each_switch_step_stamps_its_traces_with_its_own_capture_window(self) -> None:
+        # The whole point of per-trace timing: three switch steps are measured one
+        # after another, so their traces must NOT all share the collection window.
+        service, _inner, _input_switch = _switched_service(input_steps=3)
+
+        collection = service.acquire_collection(collection_id=7)
+
+        windows_by_step: dict[int, set[tuple[int, int]]] = {}
+        for trace in collection.traces:
+            step = int(trace.combo.input) // _INNER_INPUTS
+            windows_by_step.setdefault(step, set()).add(
+                (int(trace.capture_start_ns), int(trace.capture_end_ns))
+            )
+
+        self.assertEqual(sorted(windows_by_step), [0, 1, 2])
+        for step, windows in windows_by_step.items():
+            self.assertEqual(len(windows), 1, f"step {step} traces disagree on their window")
+            start_ns, end_ns = next(iter(windows))
+            self.assertGreater(start_ns, 0)
+            self.assertGreaterEqual(end_ns, start_ns)
+            # Each step's window sits inside the collection's.
+            self.assertGreaterEqual(start_ns, collection.capture_start_ns)
+            self.assertLessEqual(end_ns, collection.capture_end_ns)
+
+        # Steps are strictly ordered in time — the whole reason the collection-level
+        # window cannot stand in for a per-combo timestamp.
+        step_starts = [next(iter(windows_by_step[step]))[0] for step in sorted(windows_by_step)]
+        self.assertEqual(step_starts, sorted(step_starts))
+        self.assertGreater(len(set(step_starts)), 1)
+
 
 class ManualComboCaptureUsesTargetedAcquisitionTest(unittest.TestCase):
     """The per-combo capture session must not sweep the full widened matrix."""