[New Check]: Spike times are increasing

src/nwbinspector/checks/ecephys.py

@@ -79,3 +79,13 @@ def check_spike_times_not_in_unobserved_interval(units_table: Units, nunits: int
                     "observed intervals."
                 )
             )
+
+
+@register_check(importance=Importance.BEST_PRACTICE_VIOLATION, neurodata_type=Units)
+def check_ascending_spike_times(units_table: Units):
+    """Check that the values in the timestamps array are strictly increasing."""
+    if "spike_times" not in units_table:
+        return
+    for spike_times_per_unit in units_table["spike_times"]:
+        if not np.all(spike_times_per_unit[:-1] <= spike_times_per_unit[1:]):
+            return InspectorMessage(message=("This Units table contains spike times that are not ascending."))

tests/unit_tests/test_ecephys.py

@@ -15,6 +15,7 @@
     check_electrical_series_dims,
     check_electrical_series_reference_electrodes_table,
     check_spike_times_not_in_unobserved_interval,
+    check_ascending_spike_times,
 )
 
 
@@ -215,3 +216,31 @@ def test_check_spike_times_not_in_unobserved_interval_multiple_units():
         object_name="TestUnits",
         location="/",
     )
+
+
+def test_check_ascending_spike_times_pass():
+    units_table = Units()
+    units_table.add_unit(spike_times=[0.0, 0.1])
+    units_table.add_unit(spike_times=[1.0, 2.0])
+    assert check_ascending_spike_times(units_table=units_table) is None
+
+
+def test_check_ascending_spike_times_w_missing_spike_times_pass():
+    units_table = Units()
+    units_table.add_unit(spike_times=[0.0, 0.1])
+    units_table.add_unit(spike_times=[])
+    assert check_ascending_spike_times(units_table=units_table) is None
+
+
+def test_check_ascending_spike_times_fail():
+    units_table = Units(name="TestUnits")
+    units_table.add_unit(spike_times=[0.0, 0.1])
+    units_table.add_unit(spike_times=[2.0, 1.0])
+    assert check_ascending_spike_times(units_table=units_table) == InspectorMessage(
+        message=("This Units table contains spike times that are not ascending."),
+        importance=Importance.BEST_PRACTICE_VIOLATION,
+        check_function_name="check_ascending_spike_times",
+        object_type="Units",
+        object_name="TestUnits",
+        location="/",
+    )