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); }