sigma: unary negation dropped

[christianeu-db]

Summary

_render_sql_node (converters/sigma/src/ossie_sigma/sigma_formula.py) has no exp.Neg case, so a negated SQL expression is untranslatable and sql_to_sigma_formula returns None, though the forward path emits -[X].

Repro (real converter, HEAD ab8fc1a - EXECUTED)

sql_to_sigma_formula('-"X"') -> None
sql_to_sigma_formula('-1')   -> None

Possible fix

if isinstance(node, exp.Neg):
    return f"-({_render_sql_node(node.this, dataset_alias)})"

[christianeu-db]

cc @mattsenicksigma if you want to take a first pass

[mattsenicksigma]

Thanks for flagging @christianeu-db -> will take a pass today/tomorrow!