expectErr method

Object expectErr()

Expects the snapshot to be an Error and returns the error. Throws a StateError if the snapshot is not an Error.

Example:

err<int>(Exception('test')).expectErr(); // Exception('test')
ok(42).expectErr(); // throws StateError

Implementation

Object expectErr() {
  if (!isErr()) {
    throw StateError('Value is not an Error');
  }
  return error!;
}