track<T> method

@override T track<T>(T action())

Implementation

@override
T track<T>(T Function() action) {
  if (isStarted) {
    throw StateError('Can not be tracked twice');
  }
  T result;
  _start();
  try {
    result = action();
  } catch (_) {
    _stop();
    rethrow;
  }
  if (result is Future) {
    return result.whenComplete(_stop) as T;
  } else {
    _stop();
    return result;
  }
}