add check that scripted observations have unique id

rubin_scheduler/scheduler/surveys/scripted_surveys.py

@@ -332,14 +332,24 @@ def set_script(self, obs_wanted, append=True, add_index=True):
             self.script_id_array = np.array(
                 [int(note.split(", ")[-1]) for note in self.obs_wanted["scheduler_note"]]
             )
-            self.id_start = self.script_id_array.max() + 1
+            if np.size(self.script_id_array) > 0:
+                self.id_start = self.script_id_array.max() + 1
 
         if append & (self.obs_wanted is not None):
             self.obs_wanted = np.concatenate([self.obs_wanted, obs_wanted])
             self.obs_wanted.sort(order=["mjd", "filter"])
         else:
             self.obs_wanted = obs_wanted
 
+        # check that we have valid unique keys for observations
+        potential_keys = np.char.add(self.obs_wanted["scheduler_note"], self.obs_wanted["filter"])
+        if np.size(np.unique(potential_keys)) < np.size(self.obs_wanted):
+            msg = (
+                "Scripted observations do not have unique scheduler_note "
+                "+ filter values. Consider setting add_index=True"
+            )
+            raise ValueError(msg)
+
         self.mjd_start = self.obs_wanted["mjd"] - self.obs_wanted["mjd_tol"]
         # Here is the attribute that core scheduler checks to
         # broadcast scheduled observations in the conditions object.

tests/scheduler/test_surveys.py

@@ -209,6 +209,13 @@ def test_scripted_survey(self):
         sched.add_observations_array(completed_observations)
         assert np.sum(survey.obs_wanted["observed"]) == 3
 
+        # Make sure error gets raised if we set a script wrong
+        survey = surveys.ScriptedSurvey([])
+        observations["scheduler_note"] = ["a", "a", "c", "d", "a"]
+        with self.assertRaises(Exception) as context:
+            survey.set_script(observations, add_index=False)
+            self.assertTrue("unique scheduler_note" in str(context))
+
     def test_pointings_survey(self):
         """Test the pointing survey."""
         mo = ModelObservatory()