Fuzzy Join Empty Set Crash

[phorne-uncharted]

If the joined dataset has no rows (no overlap between left and right), then the primitive will crash with the following error:

Traceback (most recent call last):
  File "/home/ubuntu/git-projects/d3m/d3m/runtime.py", line 1109, in _do_run_step
    self._run_step(step)
  File "/home/ubuntu/git-projects/d3m/d3m/runtime.py", line 1097, in _run_step
    self._run_primitive(step)
  File "/home/ubuntu/git-projects/d3m/d3m/runtime.py", line 970, in _run_primitive
    multi_call_result = self._call_primitive_method(primitive.fit_multi_produce, fit_multi_produce_arguments)
  File "/home/ubuntu/git-projects/d3m/d3m/runtime.py", line 1073, in _call_primitive_method
    raise error
  File "/home/ubuntu/git-projects/d3m/d3m/runtime.py", line 1069, in _call_primitive_method
    result = method(**arguments)
  File "/home/ubuntu/git-projects/distil-primitives/distil/primitives/fuzzy_join.py", line 385, in fit_multi_produce
    right=right,
  File "/home/ubuntu/git-projects/d3m/d3m/primitive_interfaces/base.py", line 554, in _fit_multi_produce
    produce_results = self._multi_produce(produce_methods=produce_methods, timeout=timeout, iterations=iterations, **kwargs)
  File "/home/ubuntu/git-projects/d3m/d3m/primitive_interfaces/base.py", line 450, in _multi_produce
    results.append(getattr(self, method_name)(timeout=timeout, iterations=iterations, **arguments))
  File "/home/ubuntu/git-projects/distil-primitives/distil/primitives/fuzzy_join.py", line 332, in produce
    if type(joined[column][0]) == np.ndarray:
  File "/home/ubuntu/.env/distil/lib/python3.6/site-packages/pandas/core/series.py", line 871, in __getitem__
    result = self.index.get_value(self, key)
  File "/home/ubuntu/.env/distil/lib/python3.6/site-packages/pandas/core/indexes/base.py", line 4410, in get_value
    return libindex.get_value_at(s, key)
  File "pandas/_libs/index.pyx", line 44, in pandas._libs.index.get_value_at
  File "pandas/_libs/index.pyx", line 45, in pandas._libs.index.get_value_at
  File "pandas/_libs/util.pxd", line 98, in pandas._libs.util.get_value_at
  File "pandas/_libs/util.pxd", line 89, in pandas._libs.util.validate_indexer
IndexError: index out of bounds