Improve error message for incorrectly named index variable

[cacraigucar]

It would be helpful (if it is easy to do) to include the incorrect name for the index variable.

The current error message is:
Parsing metadata_file, '/home/cacraig/CAMDEN_heldsuarez/src/dynamics/utils/vert_coord.meta'
Parsing file, physics_types, from registry
Traceback (most recent call last):
File "/home/cacraig/CAMDEN_heldsuarez/cime_config/buildnml", line 293, in
_main_func()
File "/home/cacraig/CAMDEN_heldsuarez/cime_config/buildnml", line 289, in _main_func
buildnml(case, caseroot, "cam")
File "/home/cacraig/CAMDEN_heldsuarez/cime_config/buildnml", line 127, in buildnml
config.generate_cam_src(gen_indent)
File "/home/cacraig/CAMDEN_heldsuarez/cime_config/cam_config.py", line 1022, in generate_cam_src
dyn, gen_fort_indent)
File "/home/cacraig/CAMDEN_heldsuarez/cime_config/cam_autogen.py", line 323, in generate_registry
error_on_no_validate=True)
File "/home/cacraig/CAMDEN_heldsuarez/src/data/generate_registry_data.py", line 1544, in gen_registry
src_root, reg_dir, indent, logger)
File "/home/cacraig/CAMDEN_heldsuarez/src/data/generate_registry_data.py", line 1421, in write_registry_files
files.append(File(section, known_types, dycore, config, logger))
File "/home/cacraig/CAMDEN_heldsuarez/src/data/generate_registry_data.py", line 1061, in init
self.add_variable(obj, logger)
File "/home/cacraig/CAMDEN_heldsuarez/src/data/generate_registry_data.py", line 1086, in add_variable
logger)
File "/home/cacraig/CAMDEN_heldsuarez/src/data/generate_registry_data.py", line 529, in init
vdict))
File "/home/cacraig/CAMDEN_heldsuarez/src/data/generate_registry_data.py", line 362, in init
raise CCPPError(emsg.format(self.index_name, parent_name))
File "/home/cacraig/CAMDEN_heldsuarez/src/data/generate_registry_data.py", line 313, in index_name
return self.__index_name
AttributeError: 'ArrayElement' object has no attribute '_VarBase__index_name'
ERROR: /home/cacraig/CAMDEN_heldsuarez/cime_config/buildnml /home/cacraig/CAMDEN_heldsuarez/cime/scripts/test_camden_kessler_try06 FAILED, see above

[gold2718]

As you can see from the traceback, this error is occurring in the registry generator, not in the CCPP Framework. Please open this issue in the CAMDEN repo and close this issue.
Note, this is probably in internal bug -- even if this is due to a user data error, it is triggering an inappropriate response.