drift/moor/test/utils/expand_variables_test.dart

import 'package:moor/moor.dart' show $expandVar;
import 'package:test/test.dart';

void main() {
  test('\$expandVar test', () {
    expect($expandVar(4, 0), '');
    expect($expandVar(2, 3), '?2, ?3, ?4');
  });
}