:DESC
Check that designs which consist only of whitespace are rejected.

:ARGS
-f 170_forbid_blank_box.cfg -l
:INPUT
:OUTPUT-FILTER
:EXPECTED-ERROR 1
boxes: 170_forbid_blank_box.cfg: line 9: must specify at least one non-empty shape per design
boxes: 170_forbid_blank_box.cfg: line 9: skipping to next design
boxes: 170_forbid_blank_box.cfg: line 29: must specify at least one non-empty shape per design
boxes: 170_forbid_blank_box.cfg: line 29: skipping to next design
boxes: no valid data in config file -- 170_forbid_blank_box.cfg
boxes: no valid designs found
:EOF