cjio crashes when merging empty cityjson (ValueError: math domain error)

cjio crashes when merging multiple files and one is an empty cityJson (according to specification allowed: https://www.cityjson.org/specs/1.1.3/#cityjson-object)

with the following error:

cjio LoD2_33_388_5816_1_BE.json merge "*.json" save merged.json
Parsing LoD2_33_388_5816_1_BE.json
Merging files
Traceback (most recent call last):
  File "/home/user/.local/bin/cjio", line 8, in <module>
    sys.exit(cli())
  File "/home/user/.local/lib/python3.9/site-packages/click/core.py", line 1130, in __call__
    return self.main(*args, **kwargs)
  File "/home/user/.local/lib/python3.9/site-packages/click/core.py", line 1055, in main
    rv = self.invoke(ctx)
  File "/home/user/.local/lib/python3.9/site-packages/click/core.py", line 1689, in invoke
    return _process_result(rv)
  File "/home/user/.local/lib/python3.9/site-packages/click/core.py", line 1626, in _process_result
    value = ctx.invoke(self._result_callback, value, **ctx.params)
  File "/home/user/.local/lib/python3.9/site-packages/click/core.py", line 760, in invoke
    return __callback(*args, **kwargs)
  File "/home/user/.local/lib/python3.9/site-packages/cjio/cjio.py", line 94, in process_pipeline
    cm = processor(cm)
  File "/home/user/.local/lib/python3.9/site-packages/cjio/cjio.py", line 356, in processor
    cm.merge(lsCMs)
  File "/home/user/.local/lib/python3.9/site-packages/cjio/cityjson.py", line 1258, in merge
    if math.ceil(abs(math.log(cm.j["transform"]["scale"][0], 10))) > imp_digits:
ValueError: math domain error

example files here: (see example3 folder) https://cloud.johannes-froelich.de/s/xtwyW4rrNoeZTE5

any quick fix? since the cityJson files are generated in my case here its hard for me to avoid "empty" cityJson files

cheers and thanks!

cityjson / cjio

cjio crashes when merging empty cityjson (ValueError: math domain error) #156