restart method Null safety

Running restart(
  1. RunningController newFake,
  2. {void singleStepOnDone(
    1. CalculatorError?
    )?}
)

Implementation

Running restart(RunningController newFake,
    {void Function(CalculatorError?)? singleStepOnDone}) {
  _caller._fake = newFake;
  _caller.restarting(singleStepOnDone);
  resume();
  return _caller;
}