Merge pull request #3940 from h-mayorquin/fix_shift_times

Fix shift times when `t_start` is None

Author: alejoe91

src/spikeinterface/core/baserecording.py

@@ -547,7 +547,8 @@ def shift_times(self, shift: int | float, segment_index: int | None = None) -> N
             if self.has_time_vector(segment_index=idx):
                 rs.time_vector += shift
             else:
-                rs.t_start += shift
+                new_start_time = 0 + shift if rs.t_start is None else rs.t_start + shift
+                rs.t_start = new_start_time
 
     def sample_index_to_time(self, sample_ind, segment_index=None):
         """

src/spikeinterface/core/tests/test_time_handling.py

@@ -435,3 +435,12 @@ def _get_sorting_with_recording_attached(self, recording_for_durations, recordin
         assert sorting.has_recording()
 
         return sorting
+
+
+def test_shift_times_with_None_as_t_start():
+    """Ensures we can shift times even when t_stat is None which is interpeted as zero"""
+    recording = generate_recording(num_channels=4, durations=[10])
+
+    assert recording._recording_segments[0].t_start is None
+    recording.shift_times(shift=1.0)  # Shift by one seconds should not generate an error
+    assert recording.get_start_time() == 1.0