[yt-dev] Issue #589: Field detection catches all exceptions raised by broken fields (yt_analysis/yt)

[Nathan Goldbaum]

New issue 589: Field detection catches all exceptions raised by broken fields
https://bitbucket.org/yt_analysis/yt/issue/589/field-detection-catches-all-exceptions

Nathan Goldbaum:

Right now yt-3.0 field detection catches all exception raised during field discovery.  This happens on line 190 of `geometry_handler.py` in the 3.0a2 release.  We should only catch exceptions that indicate that a field isn't available for the dataset (e.g. `YTFieldNotFound`) and let all other exceptions, indicating that a field is broken somehow, continue to be elevated.

Once this is fixed, a user will immediately know that a newly created field that contains a bug is broken, since an exception will be raised during field detection.