public void AddFollowerAsync_ReturnsCorrect() { // Arrange _repoWrapper .Setup(x => x.Region.GetFirstAsync(It.IsAny <Expression <Func <Region, bool> > >(), It.IsAny <Func <IQueryable <Region>, IIncludableQueryable <Region, object> > >())) .ReturnsAsync(new Region() { ID = 2 }); _repoWrapper.Setup(x => x.City.GetFirstAsync(It.IsAny <Expression <Func <DataAccess.Entities.City, bool> > >(), It.IsAny <Func <IQueryable <DataAccess.Entities.City>, IIncludableQueryable <DataAccess.Entities.City, object> > >())) .ReturnsAsync(new DataAccess.Entities.City()); _repoWrapper .Setup(x => x.SaveAsync()); // Act var result = _regionService.AddFollowerAsync(It.IsAny <int>(), It.IsAny <int>()); // Assert _repoWrapper.Verify(); Assert.NotNull(result); }