Debug and update unit tests.

Author: morriscb

allensdk/brain_observatory/behavior/data_objects/stimuli/presentations.py

@@ -261,8 +261,9 @@ def from_nwb(
                 stimulus_presentations=table
             )
         trials = None
-        if add_trials_dependent_values:
+        if add_trials_dependent_values and nwbfile.trials is not None:
             trials = Trials.from_nwb(nwbfile)
+            
         return Presentations(presentations=table,
                              column_list=column_list,
                              trials=trials)
@@ -420,7 +421,9 @@ def from_stimulus_file(
             )
 
         return Presentations(
-            presentations=stim_pres_df, column_list=column_list
+            presentations=stim_pres_df,
+            column_list=column_list,
+            trials=trials
         )
 
     @classmethod

allensdk/test/brain_observatory/behavior/data_objects/test_stimuli.py

@@ -52,6 +52,8 @@ def data(self):
                     {
                         "start_time": [300.0, 330.0, 360.0],
                         "stop_time": [330.0, 360.0, 360.0],
+                        "catch": [False, True, False],
+                        "change_frame": [-99, 99, -99] 
                     }
                 )