dataSafetyColumns top-level constant
The header Play writes, in the order it writes it.
Checked as an ordered list rather than a set: the columns are read positionally below, so a file with the right names in the wrong order would parse into the wrong fields and pass every later check.
Implementation
const dataSafetyColumns = <String>[
'Question ID (machine readable)',
'Response ID (machine readable)',
'Response value',
'Answer requirement',
'Human-friendly question label',
];