public void ConvertToResponseModel_Should_Return_Enumerable_Of_Models() { var dictionary = new ModelStateDictionary(); dictionary.AddModelError("field1", "Required field is missing"); var result = dictionary.ConvertToResponseModel().ToList(); result.Should().NotBeNullOrEmpty(); result.Should().HaveCount(1); var error = result.First(); error.Field.Should().Be("field1"); error.ErrorDescription.Should().Be("Required field is missing"); }