Most internal funcions call __jat__usage() on usage errors, but this does not emit ERROR event. This means that usage errors will pass unnoticed.
jat__cmp one definitely_invalid_op two
the above will show error on console using warn() from pretty.sh, but log will simply not contain the event at all, implying that the test passed.
First possible solutions that come to mind:
Commit 68afefc fixes this issue
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