>>>
class Foo {
  Foo({
    required int x,
  })   : assert(x != 0),
        assert(x != -1);
}
<<<
class Foo {
  Foo({
    required int x,
  })  : assert(x != 0),
        assert(x != -1);
}
>>>
class Foo {
  Foo({
    int x,
  })   : assert(x != 0),
        assert(x != -1);
}
<<<
class Foo {
  Foo({
    int x,
  })  : assert(x != 0),
        assert(x != -1);
}
>>>
class Foo {
  Foo([
    int x,
  ])   : assert(x != 0),
        assert(x != -1);
}
<<<
class Foo {
  Foo([
    int x,
  ])  : assert(x != 0),
        assert(x != -1);
}