reverse_property_cascade sometimes returns IndexError instead of NoResultsError

[ARRicarte]

Hi Andrew,

I found that when querying for many different properties, reverse_property_cascade will sometimes give me an IndexError instead of a NoResultsError if the property with no results is followed by other properties. Below I've copy-pasted the error message starting from lines relevant to you.

Thanks,
Angelo

  File "/home/fas/natarajan/arr56/.local/lib/python2.7/site-packages/tangos/core/halo.py", line 331, in reverse_property_cascade
    return self.calculate_for_progenitors(*args, **kwargs)
  File "/home/fas/natarajan/arr56/.local/lib/python2.7/site-packages/tangos/core/halo.py", line 327, in calculate_for_progenitors
    return self.calculate_for_descendants(*plist, **kwargs)
  File "/home/fas/natarajan/arr56/.local/lib/python2.7/site-packages/tangos/core/halo.py", line 316, in calculate_for_descendants
    return property_description.values_sanitized(results, Session.object_session(self))
  File "/home/fas/natarajan/arr56/.local/lib/python2.7/site-packages/tangos/live_calculation/__init__.py", line 160, in values_sanitized
    unsanitized_values = self.values(halos)
  File "/home/fas/natarajan/arr56/.local/lib/python2.7/site-packages/tangos/live_calculation/__init__.py", line 138, in values
    values, _ = self.values_and_description(halos)
  File "/home/fas/natarajan/arr56/.local/lib/python2.7/site-packages/tangos/live_calculation/__init__.py", line 295, in values_and_description
    values, description = c.values_and_description(mask.mask(halos))
  File "/home/fas/natarajan/arr56/.local/lib/python2.7/site-packages/tangos/live_calculation/__init__.py", line 677, in values_and_description
    description_class = properties.providing_class(self._name, sim.output_handler_class, silent_fail=True)
  File "/home/fas/natarajan/arr56/.local/lib/python2.7/site-packages/tangos/util/consistent_collection.py", line 17, in __getattr__
    return self._ensure_consistent(values, item)
  File "/home/fas/natarajan/arr56/.local/lib/python2.7/site-packages/tangos/util/consistent_collection.py", line 26, in _ensure_consistent
    return values[0]
IndexError: list index out of range

[apontzen]

Thanks, I’ll look into it!

[apontzen]

Unfortunately I've not been able to reproduce this issue. Could you give an example e.g. using the tutorial database?

[apontzen]

Actually after a bit more playing, I was able to reproduce the issue and have pushed a fix to #72 (branch issue-46) — could you check whether this solves the issue for you?

[apontzen]

I'm closing this issue on the assumption it is fixed. Please re-open if not.