public async Task CreateManyReturnsRooms()
        {
            _mockCollection.Setup(x => x.InsertManyAsync(
                                      It.IsAny <IEnumerable <Group> >(),
                                      It.IsAny <InsertManyOptions>(),
                                      It.IsAny <CancellationToken>()
                                      )).Returns(Task.FromResult(MongoHelper.BuildMockAsyncCursor((ICollection <Group>)_groupList)));
            _mockDatabase.Setup(x => x.GetCollection <Group>(It.IsAny <string>(), It.IsAny <MongoCollectionSettings>())).Returns(_mockCollection.Object);
            var repo   = new GroupRepository(_mockDatabase.Object);
            var result = await repo.CreateManyAsync(_groupList).ConfigureAwait(false);

            Assert.NotNull(result);
            Assert.NotEmpty(result);
        }