pkg/front_end/parser_testcases/patterns/issue_51176.dart

main() {
  var ((a1,),) = ((-1,),);
  var (n: (x: a2)) = (n: (x: 42));
  var (n: (x: a3, b3), (y: c3, d3)) = (n: (x: 42, -1), (y: 1, 0));

  final ((a4,),) = ((-1,),);
  final (n: (x: a5)) = (n: (x: 42));
  final (n: (x: a6, b6), (y: c6, d6)) = (n: (x: 42, -1), (y: 1, 0));

  var ((int a7,),) = ((-1,),);
  var (n: (x: int a8)) = (n: (x: 42));
  var (n: (x: int a9, int b9), (y: int c9, int d9))
      = (n: (x: 42, -1), (y: 1, 0));

  var (n: (int, {int x}) a10, (int z, {int y}) b10)
      = (n: (x: 42, -1), (y: 1, 0));
}