public void When_AfterMapping_Then_Is_Set_On_Map() { // Arrange var map = new ClassMap(ProjectionType.Create<VehicleFrom, VehicleTo>(), new Mapper()); var sut = new ClassMapBuilder<VehicleFrom, VehicleTo>(map); var flag = false; var postMapStep = (Action<VehicleFrom, VehicleTo>) ((_, __) => flag = true); // Act sut.AfterMapping(postMapStep); map.AfterMapping(null, null); // Assert Assert.IsTrue(flag); }