public async Task When_GettingAllStandardVersions_Then_ReturnsListOfStandards(IEnumerable <Standard> standards) { _mockStandardRepository.Setup(s => s.GetAllStandards()).ReturnsAsync(standards); var result = await _standardService.GetAllStandardVersions(); Assert.IsInstanceOf <IEnumerable <Standard> >(result); Assert.AreEqual(result.Count(), standards.Count()); }