when<TResult extends Object?> method

  1. @optionalTypeArgs
TResult when<TResult extends Object?>({
  1. required TResult httpStub(
    1. String responseStubValue,
    2. int? statusCodeStubValue,
    3. Map<String, String> headersStubValue
    ),
  2. required TResult genericStub(
    1. void setUp(
      1. dynamic params
      )
    ),
})

A switch-like method, using callbacks.

As opposed to map, this offers destructuring. It is equivalent to doing:

switch (sealedClass) {
  case Subclass(:final field):
    return ...;
  case Subclass2(:final field2):
    return ...;
}

Implementation

@optionalTypeArgs
TResult when<TResult extends Object?>({
  required TResult Function(String responseStubValue,
          int? statusCodeStubValue, Map<String, String> headersStubValue)
      httpStub,
  required TResult Function(void Function(dynamic params) setUp) genericStub,
}) {
  final _that = this;
  switch (_that) {
    case _HttpStub():
      return httpStub(_that.responseStubValue, _that.statusCodeStubValue,
          _that.headersStubValue);
    case _GenericStub():
      return genericStub(_that.setUp);
    case _:
      throw StateError('Unexpected subclass');
  }
}