private async void PhoneERL_TestNewPhoneERL()
        {
            var phoneEdit = await PhoneERL.NewPhoneERL();

            Assert.NotNull(phoneEdit);
            Assert.IsType <PhoneERL>(phoneEdit);
        }
        private async void PhoneERL_TestGetPhoneERL()
        {
            var phoneEdit =
                await PhoneERL.GetPhoneERL();

            Assert.NotNull(phoneEdit);
            Assert.Equal(3, phoneEdit.Count);
        }
        private async void PhoneERL_TestAddPhoneERL()
        {
            var categoryList =
                await PhoneERL.GetPhoneERL();

            var countBeforeAdd = categoryList.Count;

            var phoneToAdd = categoryList.AddNew();

            BuildPhone(phoneToAdd);

            var updatedCategoryList = await categoryList.SaveAsync();

            Assert.NotEqual(countBeforeAdd, updatedCategoryList.Count);
        }
        private async void PhoneERL_TestDeletePhoneERL()
        {
            const int ID_TO_DELETE = 99;
            var       categoryList =
                await PhoneERL.GetPhoneERL();

            var listCount        = categoryList.Count;
            var categoryToDelete = categoryList.First(cl => cl.Id == ID_TO_DELETE);
            // remove is deferred delete
            var isDeleted = categoryList.Remove(categoryToDelete);

            var phoneListAfterDelete = await categoryList.SaveAsync();

            Assert.NotNull(phoneListAfterDelete);
            Assert.IsType <PhoneERL>(phoneListAfterDelete);
            Assert.True(isDeleted);
            Assert.NotEqual(listCount, phoneListAfterDelete.Count);
        }
        private async void PhoneERL_TestUpdatePhoneERL()
        {
            const int    ID_TO_UPDATE = 1;
            const string NOTES_UPDATE = "Updated Notes";

            var categoryList =
                await PhoneERL.GetPhoneERL();

            var phoneToUpdate = categoryList.First(cl => cl.Id == ID_TO_UPDATE);

            phoneToUpdate.Notes = NOTES_UPDATE;

            var updatedList = await categoryList.SaveAsync();

            var updatedPhone = updatedList.First(el => el.Id == ID_TO_UPDATE);

            Assert.NotNull(updatedList);
            Assert.NotNull(updatedPhone);
            Assert.Equal(NOTES_UPDATE, updatedPhone.Notes);
        }