Every rule returns null when the survey does not carry the field it scores, so an unknown is
reported as unknown by plan() rather than silently passing. A rule that treated a missing value
as a pass would make a partial survey look like a clean bill of health.
The rules, in report order.
Every rule returns null when the survey does not carry the field it scores, so an unknown is reported as unknown by
plan()rather than silently passing. A rule that treated a missing value as a pass would make a partial survey look like a clean bill of health.