namespace Example.Tests; public class CustomerValidatorTest { [Fact] public void EmptyCustomerObject_is_cannot_be_validated() { // given var customer = new Customer(); var validator = new CustomerValidator(); // when var result = validator.Validate(customer); // then result.IsValid.ShouldBeFalse(); result.Errors.ShouldNotBeEmpty(); result.Errors.Count.ShouldBe(3); } }