given<T> function
Implementation
FutureOr<T> given<T>(String description, FutureOr<T> Function() body) {
final givens = Zone.current[givenKey] as List<String>?;
if (givens == null) throw Exception('Use gwt method');
final state = Zone.current[stateKey] as State;
state.key = givenKey;
givens.add(description);
final result = body();
if (result is Future) {
return Future.sync(() async => await result);
} else {
return result;
}
}