public void GetAllPersonsReturnsOkAndListOfAllPersonsWhenEverythingIsCorrect() { var persons = new List <Person>(); _personRepositoryMock.Setup(m => m.GetAll()) .Returns(persons); var result = _sut.GetAllEntities() as OkObjectResult; Assert.That(result, Is.Not.Null); var value = result.Value as List <PersonReturnModel>; Assert.That(value, Is.Not.Null); _personRepositoryMock.Verify(m => m.GetAll(), Times.Once); }