public async Task StartTracking_Should_return_from_execution_When_geolocation_permission_is_not_validated() { _permissionValidator.ValidateGeolocationPermission().Returns(false); _geolocator.IsListening.Returns(false); await _trackerService.StartTracking(); await _geolocator.DidNotReceive().StartListeningAsync(Arg.Any <TimeSpan>(), Arg.Any <double>()); _geolocator.DidNotReceive().PositionChanged += Arg.Any <EventHandler <PositionEventArgs> >(); }